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The present work reviews recent advances in the preparation of new reversed phase packing materials such as sterically protected, bidentate, hybrid organic-inorganic and monolithic phases and phases containing embedded polar groups. The bonding chemistry involved in the preparation of these phases as well as their advantages over conventional C8 and C18 reversed phases are discussed. Understanding the reasons behind the development of these newer column packings helps analysts select the best stationary phase for a given application.

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In this work we present a theoretical model to investigate the scattering of Xe and Ne by a liquid squalane surface. The liquid surface is modeled as a grid of harmonic oscillators with frequencies adjusted to experimental vibration as frequencies of the liquid squalane and the atom-surface interaction potential is modeled by a Lennard-Jones function. The three dimensional description of the dynamics of the process which occurs at the gas-liquid interface is obtained by the classical trajectory method. The general characteristics of the dynamics of the scattering process are in good agreement with experimental data.

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La jubilación y la vejez implican la necesidad de una reorganización de los roles sociales, personales y familiares, y una adaptación al nuevo estatus social. Es una etapa crítica en la que puede aparecer un deterioro de la autoestima y el incremento del aislamiento social. Por ello, los objetivos de la presente intervención son incrementar la autoestima y disminuir el aislamiento social en el mayor jubilado.

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La calidad de vida en la población universitaria adquiere una especial importancia ya que permite obtener información sobre las condiciones de vida de los universitarios y, sobre todo, de cómo éstos las perciben. Objetivo: Evaluar la calidad de vida de los universitarios que cursan estudios en ciencias de la salud y su relación con diferentes factores tales como: hábitos de vida, parámetros antropométricos y la influencia de las distintas variables sobre su percepción. Material y Método: Estudio transversal de una muestra de 1.753 estudiantes de ciencias de la salud de nueve universidades españolas con diseño muestral aleatorio y estatrificado según curso y facultad al que se le aplicó un cuestionaro ad hoc que recogía todas las variables a estudio. Resultados: La calidad de vida percibida por los participantes fue Me = 75. Los factores explorados de la calidad de vida se co-relacionaron significativamente con la percepción global de calidad de vida de los estudiantes (p<0,001). Se establecieron 3 dimensiones y el impacto de cada una de ellas sobre la percepción de calidad de vida global fue p<0,001. Los varones percibieron mejor calidad de vida que las mujeres y también los estudiantes con menor Índice de Masa Corporal (IMC). Conclusión: Los universitarios son una población clave para realizar actividades de promoción y prevención de la salud por lo que resulta necesario crear mejores infraestucturas y recursos educativos para mejorar la CV y fomentar hábitos y estilos de vida saludable con especial atención en la alimentación y la realización de una adecuada actividad física.

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El presente informe tiene por objeto exponer los resultados correspondientes al segundo año de andadura de la Cátedra UB – Fundación Adecco para la Integración Laboral de Personas con Discapacidad (http://www.ub.edu/catedrainlab/).

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En este artículo se hace referencia a una investigación sobre la constitución de la identidad de docentes en formación y en sus primeros años de trabajo, buscando que emerjan relatos invisibilizados y tratando de aportar otra dimensión de las historias de vida en educación. Una dimensión desde la que hemos pretendido dar cuenta de la complejidad de lo que experiencia el profesorado novel y en formación para generar micro-historias que permitan un relato otro de la historia contemporánea de la educación. En este caso, desde y con el profesorado que comienza en la profesión docente.

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The demand for analytical methods suitable for accurate and reproducible determination of drug enantiomers has increased significantly in the last years. High-performance liquid chromatography (HPLC) using chiral stationary phases and capillary electrophoresis (CE) are the most important techniques used for this purpose. In this paper, the fundamental aspects of chiral separations using both techniques are presented. Some important aspects for the development of enantioselective methods, particularly for the analysis of drugs and metabolites in biological samples, are also discussed.

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Analysis of diazepam (DZP) and its active metabolite nordiazepam (NDZP) in plasma is commonly performed in clinical medicine to ensure proper therapeutic effects while minimizing the incidence of toxicity. This study aimed to optimize analytical parameters and compare two pre-treatment techniques, liquid-liquid (LLE) and solid phase extraction (SPE), as well as liquid chromatographic conditions to analyze simultaneously DZP and NDZP in plasma from 20 patients treated with a daily dose of 10 mg. Both techniques showed to be well in line with the international criteria for analytical validation, which permitted to quantify DZP (66.2 - 1148.6 ng mL-1) and NDZP (138.5 - 808.6 ng mL -1) in all samples. The correlation coefficients between SPE and LLE were respectively 0.9729 for DZP and 0.9643 for NDZP.

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A new solid phase microextraction (SPME) system, known as in-tube SPME, was recently developed using an open tubular fused-silica capilary column, instead of an SPME fiber, as the SPME device. On-line in-tube SPME is usually used in combination with high performance liquid chromatography. Drugs in biological samples are directly extracted and concentrated in the stationary phase of capillary columns by repeated draw/eject cycles of sample solution, and then directly transferred to the liquid chromatographic column. In-tube SPME is suitable for automation. Automated sample handling procedures not only shorten the total analysis time, but also usually provide better accuracy and precision relative to manual techniques. In-tube SPME has been demonstrated to be a very effective and highly sensitive technique to determine drugs in biological samples for various purposes such as therapeutic drug monitoring, clinical toxicology, bioavailability and pharmacokinetics.

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In this paper a water quality index is developed to subsidize management actions in the Atibaia River for upon protection of aquatic organisms. This index is composed of two measurable environmental parameters normaly, ammonia and dissolved oxygen, the latter representing the contribution of organic matter. Concentrations of these two variables were normalized on a scale from 0 to 100 and translated into statements of quality (excellent, good, regular, bad and very bad). The index was applied to three monitoring points in the Atibaia River and compared to other indices used by the State of São Paulo Environmental Agency (CETESB). The results showed that the degradation in this watershed follows the urban population density. The developed index is more restricted than the other ones routinely used to infer water quality.