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En este trabajo se han caracterizado la microestructura y las propiedades mecánicas alrededor de la intercara de un material multicapa de aluminio basado en las aleaciones Al 7075 y Al 2024. Las técnicas empleadas, principalmente, han sido EBSD y ensayos de cizalla para determinar propiedades mecánicas de las intercaras, en función del tiempo de solubilización durante el tratamiento térmico T6. Dicho tratamiento modifica la microestructura de las aleaciones constituyentes adyacentes a la intercara y, por tanto, las propiedades mecánicas de esta. La combinación de la ruta de procesado adecuada mediante laminación en caliente, junto con un tratamiento térmico optimizado conduce a intercaras resistentes, propensas a delaminar y, por ello, a materiales con propiedades mecánicas excelentes.

Se procesaron mediante unión por laminación, dos materiales compuestos laminados de 10 capas: cinco capas de un acero de ultraalto contenido en carbono con 1,35 % C, alternadas con otras cinco de un acero al cromo y molibdeno. La laminación en caliente consolida la unión entre las capas y afina la microestructura, reduciendo el tamaño de grano y eliminando las zonas de perlita presentes inicialmente. Se realizaron ensayos de impacto Charpy para evaluar su resistencia al impacto. El material compuesto laminado mejoró sustancialmente la tenacidad del acero de ultraalto carbono, además de duplicar la resiliencia del acero al cromo y molibdeno en la orientación "en serie". Estos resultados ponen de manifiesto la importancia de las intercaras en las propiedades mecánicas de los materiales compuestos.

Se ha procesado un material compuesto laminado de base hierro, de 7 capas alternas de dos aceros diferentes (cuatro capas de acero de ultra-alto contenido en carbono, AUAC, y tres de acero suave, AS), mediante unión por laminación y se ha estudiado su microestructura y propiedades de impacto. Se eligieron los parámetros adecuados de temperatura y de reducción de espesor para obtener una microestructura más fina que la de los aceros constituyentes originales, lo que induce una mejora en las propiedades mecánicas. Los valores de energía absorbida en el ensayo Charpy, tanto en la dirección "en paralelo" como "en serie", han mejorado sustancialmente el valor asociado al AU AC monolítico. Además, el valor obtenido en la dirección "en serie" es superior al del AS. Se observa que la delaminación, que depende de la unión de las intercaras, juega un papel importante en la deflexión de las fisuras, absorbiendo energía e imponiendo sucesivas nucleaciones de grietas en las siguientes capas.

Schizophrenia is a chronic mental disorder that affects young patients in which antipsychotic treatment is essential for sympto- matic control and preventing progression. The high rate of relapse in these patients (10%) is mainly due to the abandonment of the medication. It is necessary to find tools to increase adherence. The long acting injectable antipsychotics (depot antipsychotics) represent a useful alternative in the recent years, since there is great evidence that they improve therapeutic compliance., Objective: To evaluate the effectiveness and adherence to pharmacological treatment with depot antipsychotics in patients with psychotic disorders., Methodology: A retrospective longitudinal observational study was performed on a population of 89 subjects from Hospital Universitario Fundación Alcorcón (HUFA) with psychotic disorders, who received depot antipsychotics since September 2015 until June 2017. The incidences of new symptomatic episodes (assessed as visits to Emergency Department, general hospital admissions and psychiatric admissions) were compared at 6, 12, 24 months before and 6, 12, 14 months after the start of the depot treatment., Results: There is a significant reduction in the relative risk of general and psychiatric admissions with all depot antipsychotics. Paliperidone Palmitate is superior to the others, being the only one that reduces the number of visits to general Emergencies. Aripiprazole only decreased the relative risk of psychiatric admissions. The depot antipsychotics used had a high adherence (73%). Among the causes of non-adherence to treatment (23%), the most important is non-compliance with the prescribed regimen., Conclusion: Depot antipsychotics are an effective alternative to improve therapeutic adherence in patients with psychotic disorders, which means a lower incidence of symptoms and lower hospital requirements.

Introduction: Adult attention deficit hyperactivity disorder (ADHD) has a prevalence between 2.5% and 4% of the general adult population. Over the past few decades, self-report measures have been developed for the current evaluation of adult ADHD. The ADHD-RS is a 18-items scale self-report version for assessing symptoms for ADHD DSM-IV. A validation of Spanish version of the ADHD-RS was performed., Material and Method: The sample consisted of 304 adult with ADHD and 94 controls. A case control study was carried out (adult ADHD vs. non ADHD). The diagnosis of ADHD was evaluated with the Structured Clinical Interview for DSM-IV (SCID-I) and the Conners Adult ADHD Diagnostic Interview for DSM-IV (CAADID-II). To determinate the internal validity of the two dimensions structure of ADHD-RS an exploratory factor analysis was performed. The α-coefficients were taken as a measure of the internal consistency of the dimensions considered. A logistic regression study was carried out to evaluate the model in terms of sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV)., Results: Average age was 33.29 (SD=10.50) and 66% of subjects were men (there were no significant differences between the two groups). Factor analysis was done with a principal component analysis followed by a normalized varimax rotation. The Kaiser-Meyer-Olkin measure of sampling adequacy tests was .868 (remarkable) and the Bartlett's test of sphericity was 2 (153)=1,835.76, P<.0005, indicating the appropriateness of the factor analysis. This two-factor model accounted for 37.81% of the explained variance. The α-coefficient of the two factors was .84 and .82. The original strategy proposed 24 point for cut-off: sensitivity (81.9%), specificity (74.7%), PPV (50.0%), NPV (93.0%), kappa coefficient .78 and area under the curve (AUC) .89. The new score strategy proposed by our group suggests different cut-off for different clinical presentations. The 24 point is the best cut-off for ADHD combined presentation: sensitivity (81.9%), specificity (87.3%), PPV (78.6%), NPV (89.4%), kappa coefficient .88 and AUC .94, and 21 point is the best cut-off for ADHD predominantly inattentive presentation: sensitivity (70.2%), specificity (76.1%), PPV (71.7%), NPV (74.8%), kappa coefficient .88 and AUC .94., Conclusions: In this study, the Spanish version of the ADHD-RS is a valid scale to discriminate between ADHD adults and controls. The new proposed score strategy suggests the relevance of clinical presentations in the different cut-offs selected., (Copyright © 2017 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: The hepatic oxidative metabolism is essential for the biotransformation of a large number substances, among which are found many drugs which are commonly used in clinical practice. The nutritional status of individuals has been shown to be of influence on this function. Aging produces a deterioration of the hepatic oxidative metabolism, without the cause for this situation having been clarified. Also, aging modifies the body composition of the individuals. The objective of this study is to evaluate whether the modifications which arise in the nutritive status due to age, can alter the hepatic oxidative capacity., Material and Methods: 165 elderly people of both sexes were studied, with an average age of 82 years, and 24 young people, with an average age of 29 years. All participants were subjected to a clinical questionnaire, along with an evaluation of anthropometric, biochemical, and immunological nutritive parameters. The study of the oxidative metabolism was conducted by evaluating the kinetics of antipyrine., Results: The elderly people showed a decrease in the antipyrine clearance rate (Ap Cl) (P < 0.001), and a lengthening of their life-span (P < 0.05) with respect to the younger people. There was a significant correlation in the elderly people, between the Ap Cl and age, weight, size, the distribution volume, and the muscular area of the arm. A multiple regression analysis showed a predictive value which was independent for age, the AST, the lymphocytes, and size., Conclusion: Elderly people have a marked depression of the hepatic oxidative metabolism. The factors which participate in their nutritional situation, are of influence on this function. It is necessary to keep all the above in mind when it comes to prescribing drugs which require this type of biotransformation, in order to avoid adverse effects or drug interactions.