Eina interactiva per a l'autoaprenentatge del formigó estructural

L’objectiu principal de l’assignatura Estructures de Formigó, que s’imparteix a quart curs d’enginyeria de camins, canals i ports és que l’estudiant sigui capaç de dissenyar les estructures de formigó, amb el seu ampli ventall de condicions funcionals i ambientals, de forma competent. Per aquesta raó cal que l’estudiant pugui veure l’aplicació dels coneixements de Formigó Estructural en els diferents àmbits on es troben estructures d’aquest material, a través d’exercicis que permetin aplicar els conceptes generals, podríem dir més teòrics, a múltiples casos concrets i, si és possible, extrets de la pràctica professional. Amb la intenció de donar a l’estudiant eines que li permetin aprendre l’aplicació real dels coneixements a múltiples casos, s’ha desenvolupant una eina d’autoaprenentatge interactiva del formigó estructural, utilitzant les tecnologies de la informació, que ajuda a l'alumne a dissenyar les estructures de formigó, amb el seu ampli ventall de condicions funcionals i ambientals, de forma competent. Això es desenvolupa a través d’una col·lecció de 160 exercicis autoavaluables de 5 a 30 minuts de durada que permeten aplicar els conceptes generals (teoria) a múltiples casos concrets. L’existència de l’eina permet al professor abordar les classes pràctiques centrant-se més en els aspectes globals. L’acollida de l’eina d’autoaprenentatge per part dels estudiants ha estat molt favorable, com demostren els resultats de les enquestes fetes als estudiants

Pulmonary metastasectomy in colorectal cancer: a prospective study of demography and clinical characteristics of 543 patients in the Spanish colorectal metastasectomy registry (GECMP-CCR)

ObjectivesTo capture an accurate contemporary description of the practice of pulmonary metastasectomy for colorectal carcinoma in one national healthcare system.DesignA national registry set up in Spain by Grupo Español de Cirugía Metástasis Pulmonares de Carcinoma Colo-Rectal (GECMP-CCR).Setting32 Spanish thoracic units.ParticipantsAll patients with one or more histologically proven lung metastasis removed by surgery between March 2008 and February 2010.InterventionsPulmonary metastasectomy for one or more pulmonary nodules proven to be metastatic colorectal carcinoma.Primary and secondary outcome measuresThe age and sex of the patients having this surgery were recorded with the number of metastases removed, the interval between the primary colorectal cancer operation and the pulmonary metastasectomy, and the carcinoembryonic antigen level. Also recorded were the practices with respect to mediastinal lymphadenopathy and coexisting liver metastases.ResultsData were available on 543 patients from 32 units (6–43/unit). They were aged 32–88 (mean 65) years, and 65% were men. In 55% of patients, there was a solitary metastasis. The median interval between the primary cancer resection and metastasectomy was 28 months and the serum carcinoembryonic antigen was low/normal in the majority. Liver metastatic disease was present in 29% of patients at some point prior to pulmonary metastasectomy. Mediastinal lymphadenectomy varied from 9% to 100% of patients.ConclusionsThe data represent a prospective comprehensive national data collection on pulmonary metastasectomy. The practice is more conservative than the impression gained when members of the European Society of Thoracic Surgeons were surveyed in 2006/2007 but is more inclusive than would be recommended on the basis of recent outcome analyses. Further analyses on the morbidity associated with this surgery and the correlation between imaging studies and pathological findings are being published separately by GECMP-CCR

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Evidence for Quantization of Mechanical Rotation of Magnetic Nanoparticles

We report evidence of the quantization of the rotational motion of solid particles containing thousands of atoms. A system of CoFe 2 O 4 nanoparticles confined inside polymeric cavities has been studied. The particles have been characterized by the x-ray diffraction, transmission electron microscopy, plasma mass spectroscopy, ferromagnetic resonance (FMR), and magnetization measurements. Magnetic and FMR data confirm the presence of particles that are free to rotate inside the cavities. Equidistant, temperature-independent jumps in the dependence of the microwave absorption on the magnetic field have been detected. This observation is in accordance with the expectation that orbital motion splits the low-field absorption line into multiple lines

Identification of \u3ci\u3eFrancisella tularensis\u3c/i\u3e subsp. \u3ci\u3etularensis \u3c/i\u3eA1 and A2 Infections by Real-Time Polymerase Chain Reaction

Francisella tularensis subsp. tularensis (type A) is subdivided into clades A1 and A2. Human tularemia infections caused by A1 and A2 differ with respect to clinical outcome; A1 infections are associated with a higher case fatality rate. In this study, we develop and evaluate TaqMan polymerase chain reaction (PCR) assays for identification of A1 and A2. Both assays were shown to be specific to either A1 or A2, with sensitivities of 10 genomic equivalents. Real-time PCR results for identification of A1 and A2 were in complete agreement with results obtained by pulsed field gel electrophoresis analysis or conventional PCR when specimens from sporadic tularemia cases and a tularemia outbreak involving both A1 and A2 were tested. In addition, outbreak samples not previously typed to the clade level could be classified as A1 or A2. The assays described here provide new diagnostic tools with a level of sensitivity not previously available for identification of A1 and A2 infections

Identification of \u3ci\u3eFrancisella tularensis\u3c/i\u3e subsp. \u3ci\u3etularensis \u3c/i\u3eA1 and A2 Infections by Real-Time Polymerase Chain Reaction

Francisella tularensis subsp. tularensis (type A) is subdivided into clades A1 and A2. Human tularemia infections caused by A1 and A2 differ with respect to clinical outcome; A1 infections are associated with a higher case fatality rate. In this study, we develop and evaluate TaqMan polymerase chain reaction (PCR) assays for identification of A1 and A2. Both assays were shown to be specific to either A1 or A2, with sensitivities of 10 genomic equivalents. Real-time PCR results for identification of A1 and A2 were in complete agreement with results obtained by pulsed field gel electrophoresis analysis or conventional PCR when specimens from sporadic tularemia cases and a tularemia outbreak involving both A1 and A2 were tested. In addition, outbreak samples not previously typed to the clade level could be classified as A1 or A2. The assays described here provide new diagnostic tools with a level of sensitivity not previously available for identification of A1 and A2 infections

Moody's Correlated Binomial Default Distributions for Inhomogeneous Portfolios

This paper generalizes Moody's correlated binomial default distribution for homogeneous (exchangeable) credit portfolio, which is introduced by Witt, to the case of inhomogeneous portfolios. As inhomogeneous portfolios, we consider two cases. In the first case, we treat a portfolio whose assets have uniform default correlation and non-uniform default probabilities. We obtain the default probability distribution and study the effect of the inhomogeneity on it. The second case corresponds to a portfolio with inhomogeneous default correlation. Assets are categorized in several different sectors and the inter-sector and intra-sector correlations are not the same. We construct the joint default probabilities and obtain the default probability distribution. We show that as the number of assets in each sector decreases, inter-sector correlation becomes more important than intra-sector correlation. We study the maximum values of the inter-sector default correlation. Our generalization method can be applied to any correlated binomial default distribution model which has explicit relations to the conditional default probabilities or conditional default correlations, e.g. Credit Risk${}^{+}$, implied default distributions. We also compare some popular CDO pricing models from the viewpoint of the range of the implied tranche correlation.Comment: 29 pages, 17 figures and 1 tabl

Curs de problemes per a l'autoaprenentatge del formigó estructural

Es presenta un curs de problemes desenvolupat sobre Atenea, que ajuda a l'alumne a dissenyar les estructures de formigó, amb el seu ampli ventall de condicions funcionals i ambientals, de forma competent. Això es desenvolupa a través d’una col·lecció de 160 exercicis autoavaluables de 5 a 30 minuts de durada que permeten aplicar els conceptes generals (teoria) a múltiples casos concrets. L’existència de l’eina permet al professor abordar les classes pràctiques centrant-se més en els aspectes globals. D’acord amb les enquestes, l’acollida de l’eina d’autoaprenentatge per part dels estudiants ha estat molt favorable.Peer Reviewe

Correlation between preoperative CT scan and lung metastases according to surgical approach in patients with colorectal cancer

Introduction: The number of lung metastases (M1) of colorectal carcinoma (CRC) in relation to the findings of computed tomography (CT) is the object of study. Methods: Prospective and multicenter study of the Spanish Group for Surgery of CRC lung metastases (GECMP-CCR). The role of CT in the detection of pulmonary M1 is evaluated in 522 patients who underwent a pulmonary metastasectomy for CRC. We define M1/CT as the ratio between metastatic nodules and those found on preoperative CT. Disease-specific survival (DSS), disease-free survival (DFS), and surgical approach were analyzed using the Kaplan–Meier method. Results: 93 patients were performed by video-assisted surgery (VATS) and 429 by thoracotomy. In 90%, the M1/CT ratio was =1, with no differences between VATS and thoracotomy (94.1% vs 89.7%, p = 0.874). In the remaining 10% there were more M1s than those predicted by CT (M1/CT > 1), with no differences between approaches (8.6% vs 10%, p = 0.874). 51 patients with M1/CT > 1, showed a lower median DSS (35.4 months vs 55.8; p = 0.002) and DFS (14.2 months vs 29.3; p = 0.025) compared to 470 with M1/CT = 1. No differences were observed in DSS and DFS according to VATS or thoracotomy. Conclusions: Our study shows equivalent oncological results in the resection of M1 of CRC using VATS or thoracotomy approach. The group of patients with an M1/CT ratio >1 have a worse DSS and DFS, which may mean a more advanced disease than predicted preoperatively. Introducción El número de metástasis pulmonares (M1) de carcinoma colorrectal (CCR) en relación con los hallazgos de la tomografía computarizada (TC), es objeto de estudio. Métodos Estudio prospectivo y multicéntrico del Grupo Español de Cirugía de las metástasis pulmonares del CCR (GCMP-CCR). Se evalúa el papel de la TC en la detección de M1 pulmonares en 522 pacientes intervenidos de una metastasectomía pulmonar por CCR. Definimos como M1/CT al cociente entre los nódulos metastásicos y los hallados en la TC preoperatoria. Se analizó la supervivencia específica de enfermedad (SEE), la supervivencia libre de enfermedad (SLE) y el abordaje quirúrgico mediante el método de Kaplan-Meier. Resultados En 93 pacientes se utilizó la cirugía videoasistida (VATS) y 429 toracotomías. En un 90% el cociente M1/TC fue =1, sin diferencias entre VATS y toracotomía (94,1 vs. 89,7%; p = 0,874). En el 10% restante existían más M1 que las predichas por la TC (M1/CT > 1), sin diferencias entre abordajes (8,6 vs. 10%; p = 0,874). Cincuenta y un pacientes con M1/CT > 1, mostraron una menor mediana de SEE (35,4 vs. 55,8 meses; p = 0,002) y SLE (14,2 vs. 29,3 meses; p = 0,025) en comparación con 470 con M1/CT = 1. No se observaron diferencias en la SEE y la SLE según VATS o toracotomía. Conclusiones Nuestro estudio muestra unos resultados oncológicos equivalentes en la resección de M1 de CCR mediante abordaje VATS o toracotomía. El grupo de pacientes con un cociente M1/CT > 1 presentan una peor SEE y SLE, pudiendo significar una enfermedad más avanzada de la predicha preoperatoriamente