7 research outputs found

    Behaviour of FRP confined concrete in square columns

    Get PDF
    A significant amount of research has been conducted on FRP-confined circular columns, but much less is known about rectangular/square columns in which the effectiveness of confinement is much reduced. This paper presents the results of experimental investigations on low strength square concrete columns confined with FRP. Axial compression tests were performed on ten intermediate size columns. The tests results indicate that FRP composites can significantly improve the bearing capacity and ductility of square section reinforced concrete columns with rounded corners. The strength enhancement ratio is greater the lower the concrete strength and also increases with the stiffness of the jacket. The confined concrete behaviour was predicted according to the more accepted theoretical models and compared with experimental results. There are two key parameters which critically influence the fitting of the models: the strain efficiency factor and the effect of confinement in non-circular sections

    In Vitro Susceptibility to Ceftazidime/Avibactam and Comparators in Clinical Isolates of Enterobacterales from Five Latin American Countries

    Get PDF
    Background: High rates of resistance to third-generation cephalosporins and carbapenems in Enterobacterales have been reported in Latin America. Ceftazidime/avibactam (CZA) is the combination of a third-generation cephalosporin and a non-β-lactam β-lactamase inhibitor, which hasshown activity against isolates producing class A, C and D β-lactamases. Herein, we evaluated the activity of CZA and comparators against clinical isolates of Enterobacterales in Latin America. Methods: The activity of CZA and comparators was evaluated against clinical isolates of Enterobacterales from Argentina, Brazil, Chile, Colombia and Mexico that were collected between January 2016 andOctober 2017. One specific phenotypic subset was evaluated. A carbapenem non-susceptible (CNS) phenotype was defined as any isolate displaying a minimum inhibitory concentration (MIC) ≥1 mg/L for ertapenem. Results: CZA was active against 95.8% of all isolates and 77.5% of CNS isolates. Fosfomycin (FOS) and tigecycline (TGC) were the second most active antibiotics with 93.4% ofEnterobacterales being susceptible. Conclusions: The results of this study underline the potential therapeutic role of CZA in Latin AmericaFil: Appel, Tobias Manuel. Universidad El Bosque; ColombiaFil: Mojica, Maria Fernanda. Universidad El Bosque; ColombiaFil: De La Cadena, Elsa. Universidad El Bosque; ColombiaFil: Pallares, Cristian. Universidad El Bosque; ColombiaFil: Radice, Marcela Alejandra. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Castañeda Méndez, Paulo. Hospital Médica Sur; MéxicoFil: Jaime-Villalón, Diego. Hospital San Angel; MéxicoFil: Gales, Ana. Universidade de Sao Paulo; BrasilFil: Munita, Jose. No especifíca;Fil: Villegas, Maria. Universidad El Bosque; Colombi

    Trends of maxillofacial trauma : an update from the prospective register of a multicenter study in emergency services of Chile

    Get PDF
    Determine the behavior of the maxillofacial trauma of adults treated in 3 tertiary care centers in the central zone of Chile. Descriptive, cross-sectional, multicenter study, based on the prospective records of maxillofacial trauma cases attended between May 2016 and April 2017 by dental and maxillofacial clinical teams of Adult Emergency Units of hospitals Dr. Sótero del Río (metropolitan region), Carlos Van Buren and Dr. Gustavo Fricke (region V). Age, sex, date of occurrence, type of trauma according to ICD-10, etiology, legal medical prognosis and associated injuries were recorded, stratifying by sex and age. Chi square and unpaired Wilcoxon tests were used to compare by groups. 2.485 cases and 3.285 injuries were investigated. The male: female ratio was 1.7: 1 with age under 30 predominant, followed by older adults. Variability was observed in the yearly, weekly and daily presentation. The highest frequencies were in January and September, weekends and at night. The main etiologies were violence (42.3%), falls (13.1%) and road traffic crashes (12.9%) with differences by age and sex (p<0.05). 31,9% of the injuries occurred in hard tissue, being fractures in nasal bones predominant (S02.2). The profile of the maxillofacial trauma in Chile seems to be mixed by age, affecting young people and the elderly. The male sex predominates; the main cause, which varies by age group, is violence. Their surveillance is possible from hospital emergency records

    Atlas de las praderas marinas de España

    Get PDF
    Knowledge of the distribution and extent of seagrass habitats is currently the basis of management and conservation policies of the coastal zones in most European countries. This basic information is being requested through European directives for the establishment of monitoring programmes and the implementation of specific actions to preserve the marine environment. In addition, this information is crucial for the quantification of the ecological importance usually attributed to seagrass habitats due to, for instance, their involvement in biogeochemical cycles, marine biodiversity and quality of coastal waters or global carbon budgets. The seagrass atlas of Spain represents a huge collective effort performed by 84 authors across 30 Spanish institutions largely involved in the scientific research, management and conservation of seagrass habitats during the last three decades. They have contributed to the availability of the most precise and realistic seagrass maps for each region of the Spanish coast which have been integrated in a GIS to obtain the distribution and area of each seagrass species. Most of this information has independently originated at a regional level by regional governments, universities and public research organisations, which explain the elevated heterogeneity in criteria, scales, methods and objectives of the available information. On this basis, seagrass habitats in Spain occupy a total surface of 1,541,63 km2, 89% of which is concentrated in the Mediterranean regions; the rest is present in sheltered estuarine areas of the Atlantic peninsular regions and in the open coastal waters of the Canary Islands, which represents 50% of the Atlantic meadows. Of this surface, 71.5% corresponds to Posidonia oceanica, 19.5% to Cymodocea nodosa, 3.1% to Zostera noltii (=Nanozostera noltii), 0.3% to Zostera marina and 1.2% to Halophila decipiens. Species distribution maps are presented (including Ruppia spp.), together with maps of the main impacts and pressures that has affected or threatened their conservation status, as well as the management tools established for their protection and conservation. Despite this considerable effort, and the fact that Spain has mapped wide shelf areas, the information available is still incomplete and with weak precision in many regions, which will require an investment of major effort in the near future to complete the whole picture and respond to demands of EU directives

    Modelos de cálculo del hormigón confinado con FRP. Estudio comparativo

    Full text link
    Investigación experimental sobre pilares de hormigón reforzados con FRP. El confinamiento con un encamisado de FRP se ha convertido en un método habitual de refuerzo de pilares de hormigón armado en estructuras existentes como puentes o edificios. Numerosos estudios experimentales han demostrado que se trata de un modo eficaz de incrementar considerablemente la resistencia del hormigón. En los últimos años se están proponiendo también diferentes modelos teóricos y se han publicado en diversos países guías y recomendaciones con diversas ecuaciones para el cálculo. En este trabajo se revisan las formulaciones propuestas en las principales recomendaciones publicadas incidiendo en los dos aspectos que se han identificado como claves en el comportamiento del hormigón confinado con FRP: la deformación última efectiva del FRP y la influencia de la forma de la sección del pilar en la eficacia del confinamient

    MELD 3.0 adequately predicts mortality and renal replacement therapy requirements in patients with alcohol-associated hepatitis

    Get PDF
    Model for End-Stage Liver Disease (MELD) score better predicts mortality in alcohol-associated hepatitis (AH) but could underestimate severity in women and malnourished patients. Using a global cohort, we assessed the ability of the MELD 3.0 score to predict short-term mortality in AH. This was a retrospective cohort study of patients admitted to hospital with AH from 2009 to 2019. The main outcome was all-cause 30-day mortality. We compared the AUC using DeLong's method and also performed a time-dependent AUC with competing risks analysis. A total of 2,124 patients were included from 28 centres from 10 countries on three continents (median age 47.2 ± 11.2 years, 29.9% women, 71.3% with underlying cirrhosis). The median MELD 3.0 score at admission was 25 (20-33), with an estimated survival of 73.7% at 30 days. The MELD 3.0 score had a better performance in predicting 30-day mortality (AUC:0.761, 95%CI:0.732-0.791) compared with MELD sodium (MELD-Na; AUC: 0.744, 95% CI: 0.713-0.775; p = 0.042) and Maddrey's discriminant function (mDF) (AUC: 0.724, 95% CI: 0.691-0.757; p = 0.013). However, MELD 3.0 did not perform better than traditional MELD (AUC: 0.753, 95% CI: 0.723-0.783; p = 0.300) and Age-Bilirubin-International Normalised Ratio-Creatinine (ABIC) (AUC:0.757, 95% CI: 0.727-0.788; p = 0.765). These results were consistent in competing-risk analysis, where MELD 3.0 (AUC: 0.757, 95% CI: 0.724-0.790) predicted better 30-day mortality compared with MELD-Na (AUC: 0.739, 95% CI: 0.708-0.770; p = 0.028) and mDF (AUC:0.717, 95% CI: 0.687-0.748; p = 0.042). The MELD 3.0 score was significantly better in predicting renal replacement therapy requirements during admission compared with the other scores (AUC: 0.844, 95% CI: 0.805-0.883). MELD 3.0 demonstrated better performance compared with MELD-Na and mDF in predicting 30-day and 90-day mortality, and was the best predictor of renal replacement therapy requirements during admission for AH. However, further prospective studies are needed to validate its extensive use in AH. Severe AH has high short-term mortality. The establishment of treatments and liver transplantation depends on mortality prediction. We evaluated the performance of the new MELD 3.0 score to predict short-term mortality in AH in a large global cohort. MELD 3.0 performed better in predicting 30- and 90-day mortality compared with MELD-Na and mDF, but was similar to MELD and ABIC scores. MELD 3.0 was the best predictor of renal replacement therapy requirements. Thus, further prospective studies are needed to support the wide use of MELD 3.0 in AH

    Naufrágio, cativeiro, e relações ibéricas: a História trágico-marítima num contexto comparativo

    No full text
    corecore