Dynamic characterisation of interlaminar fracture toughness in carbon fibre epoxy composite laminates

In this work, the rate dependence of mode I interlaminar fracture toughness for two different materials systems, IM7/8552 and IM7/M91, both unidirectional UD carbon-fibre epoxy composite laminates have been examined over a wide range of loading rates from 0.5 mm/min up to 2000 mm/s at room temperature. Quasi-static fracture tests were performed using a DCB (double-cantilever beam) method with a screw-driven testing machine, while the dynamic tests were carried out using a WIF (wedge-insert fracture) specimen loaded dynamically in a hydraulic system. For performing the tests at high displacement rates, a special setup was designed and manufactured which allowed the insertion of the wedge within the DCB specimens at different cross-head displacement rates. The experimental technique used a pair of strain gauges attached to the bending surface of one of the arms of the cantilever beams and far from the initial crack tip. The peak values of the recorded strain were used to determine the fracture toughness under dynamic conditions through use of the compliance calibration method. A finite element model was developed to check the consistency of the measurements and validate the data reduction method used. The results exhibited rate insensitive behaviour in the case of the IM7/8552 laminates while IM7/M91 showed the contrary behaviour with maximum peak at 500 mm/s of displacement rate, with a toughness increase of 95% with respect to the quasi-static conditions.The research leading to these results has received funding from the European Union as Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 722096, DYNACOMP project

Prótesis modular de cadera Poropalcar : resultados clínicos en 106 pacientes con 3 años de evolución

Los resultados tras reemplazamiento total de cadera con prótesis de superficie porometal «poropros», para fijación biológica, han sido evaluados en 106 pacientes después de tres años de evolución. La valoración clínica se ha realizado según el sistema de Harris modificado, obteniendo un 91,5% de buenos resultados y un 8,5% de resultados regulares incluyendo todos los enfermos de cualquier edad y patología. El estudio realizado a partir de parámetros clínicos y radiográficos permite apreciar una buena fijación primaria de la prótesis y una excelente estabilidad de la misma, tanto para el componente femoral como cotiloideo.In a series of 106 patients who undewent porocoated total hip arthroplasty, the results were evaluated after three years follow-up. Harris'score was used for clinical assesment, obtaining 91,5% of good results and 8,5% of fair results, including all the cases whichever aetiology and age. Clinical and radiographic studies showed a good primary fixation and excellent stability in both the acetabular and the femoral stem components

¿Cuánto vale el carbono fijado por el castañar de la sierra de Huelva?

MEDIO RURAL Y SOSTENIBILIDAD IV CONGRESO ANDALUZ DE DESARROLLO SOSTENIBLE VIII CONGRESO ANDALUZ DE CIENCIAS AMBIENTALE

La artroscopia de rodilla: experiencia de 474 casos

El objetivo de este trabajo es dar a conocer los resultados de un estudio de 474 artroscopias realizadas en nuestro Servicio de Cirugía Ortopédica y Traumatología desde el mes de enero 1988 hasta agosto 1992. La edad media de los pacientes fue de 32 años, con una mayor incidencia en el sexo masculino (73%). La patología más frecuente correspondió a la meniscopatía interna (48%). Tuvimos una estancia media hospitalaria de 3 días, apreciándose una relación inversa entre ésta y la edad del paciente. La complicación más habitual en el post-operatorio fue el derrame sinovial (3%) siendo necesaria al artrocentesis para su desaparición en el plazo de 1-2 semanas.This work was aimed at presenting the results of 474 diagnostic artroscopies of the knee performed in our Department of orthopaedic surgery from January 1988 to August 1992. The mean age of the patients was 32 years. There was a greater incidence in males (73%). The most frequent pathologic finding was medial meniscopathy (48%). The mean period of hospitalization was 3 days. There was an opposite relationship betwen the hospitalization period and the age of the patient. As complications, synovial effusion was found in 3% of cases, synovial fluid evacuation been necessary

Prótesis total de cadera con doble recubrimiento de porometal e hidroxiapatita: resultados preliminares

El objetivo de este trabajo es evaluar la eficacia de la prótesis con superficie de Poropatita, recubrimiento doble de Poropros e Hidroxiapatita, para su fijación ósea directa en el reemplazo total de cadera. El estudio ha sido llevado a cabo en 80 pacientes con un seguimiento mínimo de 3 años. La valoración clínica se ha realizado según el sistema de Harris modificado, obteniendo un 90% de buenos resultados y un 10% de resultados regulares en la serie estudiada. El análisis, revisado a partir de parámetros clínicos y radiográficos, permite apreciar que el recubrimiento de un metal poroso con hidroxiapatita supone un mecanismo de seguridad en la fijación primaria como secundaria del implante. La estabilidad inmediata del componente femoral y cotiloideo, factor importante en la osteointegración del implante.This study was aimed at evaluating the outcome in terms of primary bone fixation of a total hip prosthesis coated with Poropatita® , o double coating of porous-metal and hidroxyapatite. The study reviews 80 patients operated on with a minimum follow-up of 3 years. A modified Harris score was used for clinical assessment. Good clinical results wer obtained in 9 0% of patients, while 10% achieved a fair outcome. Based on clinical and radiographic parameters, porous-metal and hidroxyapatite double coating provides both excellent primary and secondary bone fixation of the prosthetic components. Primary stability of both femoral stem and cup seens to be an important factor for osteointegration of the implant

Deformed defects for scalar fields with polynomial interactions

In this paper we use the deformation procedure introduced in former work on deformed defects to investigate several new models for real scalar field. We introduce an interesting deformation function, from which we obtain two distinct families of models, labeled by the parameters that identify the deformation function. We investigate these models, which identify a broad class of polynomial interactions. We find exact solutions describing global defects, and we study the corresponding stability very carefully.Comment: 8 pages, 5 eps figures, to appear in PR

Serum levels of caspase-cleaved cytokeratin-18 and mortality are associated in severe septic patients: Pilot study

Objective: Apoptosis is increased in sepsis. Cytokeratin 18 (CK-18), a protein of the intermediate filament group present in most epithelial and parenchymal cells, is cleaved by the action of caspases and released into the blood as caspase-cleaved CK (CCCK)-18 during apoptosis. Circulating levels of CCCK-18 have scarcely been explored in septic patients. In one study with 101 severe septic patients, the authors reported higher serum CCCK-18 levels in non-survivors than in survivors; however, the sample size was too small to demonstrate an association between serum CCCK-18 levels and early mortality and whether they could be used as a biomarker to predict outcomes in septic patients. Thus, these were the objectives of this study with a large series of patients. Methods: We performed a prospective, multicenter, observational study in six Spanish Intensive Care Units with 224 severe septic patients. Blood samples were collected at the time that severe sepsis was diagnosed to determine serum levels of CCCK-18, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-10. The end point was 30-day mortality. Results: Non-surviving patients (n = 80) showed higher serum CCCK-18 levels (P391 u/L were associated with 30-day survival (Odds ratio = 2.687; 95% confidence interval = 1.449-4.983; P = 0.002), controlling for SOFA score, serum lactic acid levels and age. Kaplan-Meier survival analysis showed that the risk of death in septic patients with serum CCCK-18 levels >391 u/L was higher than in patients with lower values (Hazard Ratio = 3.1; 95% CI = 1.96-4.84; P<0.001). Serum CCCK-18 levels were positively associated with serum levels of IL-6 and lactic acid, and with SOFA and APACHE scores. Conclusions: The major novel finding of our study, the largest cohort of septic patients providing data on circulating CCCK-18 levels, was that serum CCCK-18 levels are associated with mortality in severe septic patients

La prótesis de cadera con recubrimiento de vidrio Primeros resultados con 2 años de evolución

El presente trabajo analiza los primeros resultados clínicos y radiográficos de un estudio con la prótesis de cadera no cementada con recubrimiento «de vidrio» a nivel metafísario (prótesis CRM). La casuística comprende 80 artroplastias totales implantadas desde 1991 a 1994 con un seguimiento mínimo de 2 años. La evolución clínica, valorada según el sistema de Harris modificado, ha sido satisfactoria en el 90% de los enfermos. La observación radiográfica ha mostrado buena fijación y orientación de los componentes femorales en 72 casos. La conclusión de este análisis preliminar permite apreciar que el recubrimiento protésico con cerámica de vidrio supone un mecanismo de seguridad en la fijación primaria y secundaria de la prótesis de cadera.This work analizes the first clinical and radiological results of a cementless hip prosthesis with glass coating at metaphyseal level (CRM prosthesis). A total of 80 arthroplasties implanted since may 1991 to 1994 were studied with a two year follow-up. The clinical assesment was done by the modified Harris score, being satisfactory in 90% of the patients. The radiological study demonstrated good fixation and orientation of the prosthetic compounds in 72 cases. The prosthetic model studied provides a security mechanism both for primary and secondary fixation of the femoral stem and acetabular cup

Molecular diversity within clones of cv. Tannat (Vitis vinifera)

DNAs from 9 clones of cv. Tannat (Vitis vinifera) were analyzed at 89 microsatellite loci. Only one, VMCNg 1d12, showed a differential pattern that separated the clones in two groups. The statistical analysis of concentrations for aroma compounds from microvinifications also resulted in the same two groupings of clones. Many analyzed microsatellite loci amplified only one allele, implying that Tannat is a highly homozygous variety. For a given set of 15 microsatellites the level of homozygosity was 53 % for Tannat, in contrast to 6 % for Pinot, 20 % for both Cabernet Franc and Chardonnay and 33 % for Cabernet Sauvignon. We provide molecular data for Tannat, originating from southwestern France and nowadays becoming the emblematic cultivar of Uruguayan fine red wines. We also report a correlation between aroma-related compounds and molecular markers within clones of a cultivar.