Evaluación de la eficacia de una reparación para hormigón contaminado con cloruros

This report describes several tests that are being carried out on a viaduct near Madrid City, whose reinforcements have been seriously damaged by corrosion. These tests consist in measuring corrosion potentials and in a time soon to come, they will include the measurement of corrosion rates by means of the apparent Polarization Resistance. A methodology of laboratory tests to evaluate the protective capacity of the repairing system used towards the reinforcements is also included. Tests results have reported that the repairing materials employed do not fit the repassivating and protective function they should satisfy. Finally, it is also recalled to attention the real need in developing suitable test specifications able to provide a characterization of these repairing materials when they are going to be employed in structures damaged by corrosion in reinforcements.En el presente trabajo se describen los ensayos que se están efectuando en un viaducto de las cercanías de Madrid y que tía sufrido importantes daños por corrosión de armaduras. Estos Ensayos consisten en la medida de los potenciales de corrosión y en un próximo futuro, de la velocidad de corrosión (método de la Resistencia de Polarización Aparente). También se presenta la metodología de los ensayos de laboratorio efectuados para caracterizar la capacidad protectora hacia las armaduras del sistema de reparación utilizado en el viaducto. Los resultado de estos ensayos han mostrado que los materiales de reparación no resultan idóneos para la función repasivante y protectora que deberán desempeñar. Se destaca, finalmente, la necesidad de desarrollar una normativa de ensayos adecuada que permita caracterizar a estos materiales de reparación cuando van a ser usados en obras dañadas por corrosión de armaduras

Functional characterization of the complement receptor type 1 and its circulating ligands in patients with schizophrenia

<p>Abstract</p> <p>Background</p> <p>Whereas the complement system alterations contribute to schizophrenia, complement receptors and regulators are little studied. We investigated complement receptor type 1 (CR1) expression on blood cells, the levels of circulating immune complexes (CIC) containing ligands of CR1, C1q complement protein and fragments of C3 complement protein (C1q-CIC, C3d-CIC), and CR1 C5507G functional polymorphism in schizophrenia patients and controls.</p> <p>Results</p> <p>We found an increased C1q-CIC level and CR1 expression on blood cells, elevated number of CR1 positive erythrocytes and reduced number of CR1 positive lymphocytes and monocytes in patients compared to controls. No difference in the levels of C3d-CIC between groups was observed. Higher CR1 expression on erythrocytes in CC genotype versus CG+GG for both groups was detected, whereas no difference was observed for other cell populations. Our results indicated that schizophrenia is associated with the increased CR1 expression and C1q-CIC level.</p> <p>Conclusions</p> <p>Our study for the first time indicated that schizophrenia is associated with the increased CR1 expression and C1q-CIC level. Further studies in other ethnic groups are needed to replicate these findings.</p

Cross-national variations in reported discrimination among people treated for major depression worldwide: The ASPEN/INDIGO international study

Background: No study has so far explored differences in discrimination reported by people with major depressive disorder (MDD) across countries and cultures. Aims: To (a) compare reported discrimination across different countries, and (b) explore the relative weight of individual and contextual factors in explaining levels of reported discrimination in people with MDD. Method: Cross-sectional multisite international survey (34 countries worldwide) of 1082 people with MDD. Experienced and anticipated discrimination were assessed by the Discrimination and Stigma Scale (DISC). Countries were classified according to their rating on the Human Development Index (HDI). Multilevel negative binomial and Poisson models were used. Results: People living in 'very high HDI' countries reported higher discrimination than those in 'medium/low HDI' countries. Variation in reported discrimination across countries was only partially explained by individual-level variables. The contribution of country-level variables was significant for anticipated discrimination only. Conclusions: Contextual factors play an important role in anticipated discrimination. Country-specific interventions should be implemented to prevent discrimination towards people with MDD

La recherche scientifique face à la pêche artisanale = Research and small-scale fisheries

A fisheries development administrator and a researcher carried out a survey in eleven African countries to gain a better understanding of current physical and human problems in African fisheries, in order to assess foreign aid from recipient's perspective and to suggest future action. The objective is for the Canadian International Development Agency (CIDA) to become more aware of the importance of African small-scale fisheries. The survey was conducted using questionnaires at the "second level" : it was answered not by the small-scale fishermen themselves but by people who are directly involved with them and know them best, i.e. the administrators, technicians, researchers and sociologists. The results of the study show that the most pressing problems are not so much technical as organisational, economic, and even political, and call for serious interdisciplinary research efforts. (Résumé d'auteur

Determinación de cloro en hormigones por fluorescencia de Rayos X

Not availableLos hormigones pueden contener en su masa cloro procedente de adiciones, como cloruro sódico, para evitar el hielo formado en la construcción de pistas; cloruro magnésico, procedente de un mal lavado de las arenas de playa usadas como áridos en la fabricación del hormigón; o también el cloruro calcico, añadido para acelerar el proceso de fraguado. Este último toma parte activa en la formación de fases constitutivas como es el cloroaluminato. Uno de los constituyentes del clinker es el aluminato tricálcico, que reacciona rápidamente con el agua, dando el llamado fraguado rápido; para evitarlo, al molturar el clinker, se le añade yeso para convertirlo en cemento