Search results for "AREs"
showing 10 items of 1717 documents
Simultaneous spectrophotometric determination of calcium and magnesium in mineral waters by means of multivariate partial least-squares regression.
1997
A method for simultaneous spectrophotometric determination of calcium and magnesium in mineral waters using multivariate calibration methods is proposed. The method is based on the development of the reaction between the analytes and Methylthymol Blue at pH 11. Two operational modes were used: static (spectral information) and flow injection (FI) (spectral and kinetic information). The selection of variables was studied. A series of synthetic solutions containing different concentrations of calcium and magnesium were used to check the prediction ability of the partial least-squares models. The method was applied to the analysis of mineral waters and the results were compared with those obta…
Optimisation of chromatographic resolution using objective functions including both time and spectral information.
2014
The optimisation of the resolution in high-performance liquid chromatography is traditionally performed attending only to the time information. However, even in the optimal conditions, some peak pairs may remain unresolved. Such incomplete resolution can be still accomplished by deconvolution, which can be carried out with more guarantees of success by including spectral information. In this work, two-way chromatographic objective functions (COFs) that incorporate both time and spectral information were tested, based on the peak purity (analyte peak fraction free of overlapping) and the multivariate selectivity (figure of merit derived from the net analyte signal) concepts. These COFs are s…
Science based calibration for the extraction of 'analyte-specific' HPLC-DAD chromatograms in environmental analysis
2010
Multivariate science based calibration (SBC) has been applied to the resolution of overlapped peaks in liquid chromatography with diode array detection (LC-DAD). Complex river water samples spiked with 11 pharmaceutical substances resulted in poorly resolved chromatograms containing additional peaks from interfering matrix compounds and a change in the background absorbance due to the mobile phase gradient. Applying the present multivariate approach it was possible to resolve all 11 analytes from overlapping peaks, obtaining linear calibration lines (R2 > 0.96). Recovery percentages on spiked samples ranged between 74.6 and 113.5%, which are quite satisfactory taking into account the low co…
Multivariate optimization approach for chiral resolution of drugs using human serum albumin in affinity electrokinetic chromatography-partial filling…
2005
The enantiomeric resolution of chiral compounds using HSA by means of affinity EKC (AEKC)-partial filling technique is the result of a delicate balance between different experimental variables such as protein concentration, running pH (background electrophoretic buffer, protein and compound solutions) and protein solution plug length. In this paper multivariate optimization approaches for chiral separation of four basic drugs (alprenolol, oxprenolol, promethazine and propranolol) using HSA as chiral selector in AEKC-partial filling technique are studied. The experimental conditions to achieve maximum resolution are optimized using the Box-Behnken experimental design. Partial least squares a…
Determination of biochemical parameters in human serum by near-infrared spectroscopy
2014
NIR offers multiple advantages for serum analysis, permitting a fast and direct determination of several parameters simultaneously, with low sample handling and without the need for reagents during the measurement step. The aim of this paper was to provide an evaluation of this technique in a real world scale, for the simultaneous determination of several parameters and based on a considerable number of samples. Direct near infrared (NIR) absorbance measurements were used to determine the concentration of clinical parameters in human serum that are required in routine biochemical tests. Total protein, albumin, total cholesterol, high-density lipoprotein (HDL cholesterol), low-density lipopr…
L'anarquisme i el camperolat valencià: la readaptació d'una ideologia d'élites per la cultura popular
1992
EL PRESENTE ARTICULO TRATA DE EXPLICAR LA READAPTACION QUE CIERTOS INDIVIDUOS DEL MUNDO RURAL VALENCIANO HICIERON A PRINCIPIOS DE NUESTRO SIGLO DE ESA CONTRADICTORIA IDEOLOGIA A LA QUE LLAMAMOS ANARQUISMO. EL ANARQUISMO RURAL VALENCIANO FUE EL RESULTADO DE UN PROCESO DE ACULTURACION DONDE SE FUNDIERON DOS REALIDADES MENTALES DISTINTAS: UNA IDEOLOGIA HEREDERA DE FILOSOFIAS DIECIOCHESCAS Y DECIMONONICAS ELABORADA POR INTELECTUALES URBANOS Y UNA MILENARIA CULTURA RURAL MEDITERRANEA. ESTE "ANARQUISMO POPULAR" TUVO SU ECLOSION MAS NOTABLE Y LLAMATIVA EN 1936: UNA MEZCLA DE SUEÑOS DE FRATERNIDAD Y DE PUREZA MORAL, RITUALES DE SANGRE Y FUEGO DE PASMOSA ANTIGÜEDAD Y CONCRECIONES ECONOMICAS MAS O ME…
Anticipated Grief in Relatives of People with Alzheimer's Disease: Discourse Analysis
2021
Resumen La enfermedad de Alzheimer (EA) es la demencia más frecuente, considerada un proceso crónico e incurable. Los cuidadores de personas con EA pueden experimentar duelo anticipado. El objetivo fue observar el desarrollo de duelo anticipado en familiares de personas con EA. Participaron 10 cuidadores familiares de personas con EA en estado moderado o avanzado (70 % mujeres), de entre 18 y 80 años. Respondieron una entrevista semiestructurada (sentimientos, reconocimiento de la muerte, reorganización familiar, esperanza, facilitación o resistencia a la muerte y aproximación o distanciamiento del familiar). Se empleó la técnica del análisis cualitativo del contenido empleando la triangula…
La Fiesta de las Fallas : una liturgia civil del valencianismo temperamental
1992
La fiesta de las Fallas
Videotutoriales para la enseñanza de los Sistemas de Información Geográfica aplicados a la arqueología
2019
La experiencia que presentamos aquí se llevó a cabo durante el curso 2018-2019 en las clases prácticas de la asignatura Metodología Arqueológica (tercer curso del grado de Historia). El objetivo de aprendizaje principal de las clases prácticas de esta asignatura se focaliza en que el alumnado se familiarice con las herramientas básicas de los Sistemas de Información Geográfica (SIG) que le permitan resolver problemas de naturaleza arqueológica. Para ello, durante el curso, decidimos aplicar nuevos recursos (vídeo tutoriales) y nuevas metodologías (Flipped Teaching), con el interés de mejorar los resultados de aprendizaje del alumnado. La metodología implica la inversión de la taxonomía de B…
Sobre cerámicas Helenísticas en Iberia / Hispania. Significado y funcionalidad
2012
In this work we are going to take a chronological and typological tour by studying the iconography that appears in the Hellenistic wares imported from the Central and Oriental Mediterranean between 3rd and 2nd centuries BC in Hispania Citerior, in particular from Cartagena. We are going to analyze its functionality in the places of origin, and with the help of the Hispanic contexts we will conclude whether its presence here is a consequence of a certain commercial dynamic, or if it answers to a decorative preference, of taste or trend; even if the images are significant related to ritual or convivial uses, public or private, by the local inhabitant who acquires and uses them.