994 resultados para ESI MS


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L'execució d'aquest projecte ha volgut reflectir quines són les capacitats professionals més valorades actualment, poder entendre quines són les condicions actuals i reflexionar sobre quina és la cobertura que els plans educatius actuals -en l'àmbit de l'enginyeria informàtica- brinden a aquesta evolució, contribuint amb aquest estudi a l'objectiu general de l'àrea de competències professionals d'apropar el món acadèmic al laboral.

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La actividad profesional es fundamental en la vida de cualquier persona y en el caso de las que padecen una discapacidad tiene una gran importancia para contribuir a configurar su identidad adulta. En este sentido, la finalidad del artículo es valorar la importancia del trabajo en los procesos de participación social y de calidad de vida de las personas con discapacidad. Por ello, en el artículo se pone de manifiesto la relación que se establece entre la dimensión laboral y la integración social de los individuos con discapacidad mediante el análisis de investigaciones desarrolladas en nuestro contexto, entre las que figuran diversos estudios realizados por nuestro grupo de investigación durante los últimos años. Con la voluntad de conocer con más detalle esta cuestión, se presenta una investigación reciente realizada por nuestro equipo. En ella desarrollamos un estudio de casos centrado en personas con discapacidad psíquica que han participado en experiencias de integración laboral en el mercado ordinario, con el objetivo de obtener información sobre la incidencia de la inserción laboral en diferentes dimensiones de la vida de los trabajadores con discapacidad. Los resultados nos permiten valorar que la experiencia genera cambios positivos, sobre todo a nivel personal (expectativas personales, potenciación del proyecto de vida, mejora de competencias…). Sin embargo, a pesar de que se aprecian mejoras en la dimensión social, el estudio plantea la necesidad de emprender acciones alternativas para potenciar la participación comunitaria de las personas implicadas en la investigación. El artículo concluye con algunas propuestas orientadas a mejorar los procesos de inserción social del colectivo

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A headspace solid-phase microextraction procedure (HS-SPME) was developed for the profiling of traces present in 3,4-methylenedioxymethylampethamine (MDMA). Traces were first extracted using HS-SPME and then analyzed by gas chromatography-mass spectroscopy (GC-MS). The HS-SPME conditions were optimized using varying conditions. Optimal results were obtained when 40 mg of crushed MDMA sample was heated at 80 °C for 15 min, followed by extraction at 80 °C for 15 min with a polydimethylsiloxane/divinylbenzene coated fibre. A total of 31 compounds were identified as traces related to MDMA synthesis, namely precursors, intermediates or by-products. In addition some fatty acids used as tabletting materials and caffeine used as adulterant, were also detected. The use of a restricted set of 10 target compounds was also proposed for developing a screening tool for clustering samples having close profile. 114 seizures were analyzed using an SPME auto-sampler (MultiPurpose Samples MPS2), purchased from Gerstel GMBH & Co. (Germany), and coupled to GC-MS. The data was handled using various pre-treatment methods, followed by the study of similarities between sample pairs based on the Pearson correlation. The results show that HS-SPME, coupled with the suitable statistical method is a powerful tool for distinguishing specimens coming from the same seizure and specimens coming from different seizures. This information can be used by law enforcement personnel to visualize the ecstasy distribution network as well as the clandestine tablet manufacturing.

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The aim of this work is to present a new concept, called on-line desorption of dried blood spots (on-line DBS), allowing the direct analysis of a dried blood spot coupled to liquid chromatography mass spectrometry device (LC/MS). The system is based on an inox cell which can receive a blood sample (10 microL) previously spotted on a filter paper. The cell is then integrated into LC/MS system where the analytes are desorbed out of the paper towards a column switching system ensuring the purification and separation of the compounds before their detection on a single quadrupole MS coupled to atmospheric pressure chemical ionisation (APCI) source. The described procedure implies that no pretreatment is necessary in spite the analysis is based on whole blood sample. To ensure the applicability of the concept, saquinavir, imipramine, and verapamil were chosen. Despite the use of a small sampling volume and a single quadrupole detector, on-line DBS allowed the analyses of these three compounds over their therapeutic concentrations from 50 to 500 ng/mL for imipramine and verapamil and from 100 to 1000 ng/mL for saquinavir. Moreover, the method showed good repeatability with relative standard deviation (RSD) lower than 15% based on two levels of concentration (low and high). Function responses were found to be linear over the therapeutic concentration for each compound and were used to determine the concentrations of real patient samples for saquinavir. Comparison of the founded values with those of a validated method used routinely in a reference laboratory showed a good correlation between the two methods. Moreover, good selectivity was observed ensuring that no endogenous or chemical components interfered with the quantitation of the analytes. This work demonstrates the feasibility and applicability of the on-line DBS procedure for bioanalysis.

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U-Pb dating of zircons by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) is a widely used analytical technique in Earth Sciences. For U-Pb ages below 1 billion years (1 Ga), Pb-206/U-238 dates are usually used, showing the least bias by external parameters such as the presence of initial lead and its isotopic composition in the analysed mineral. Precision and accuracy of the Pb/U ratio are thus of highest importance in LA-ICPMS geochronology. We consider the evaluation of the statistical distribution of the sweep intensities based on goodness-of-fit tests in order to find a model probability distribution fitting the data to apply an appropriate formulation for the standard deviation. We then discuss three main methods to calculate the Pb/U intensity ratio and its uncertainty in the LA-ICPMS: (1) ratio-of-the-mean intensities method, (2) mean-of-the-intensity-ratios method and (3) intercept method. These methods apply different functions to the same raw intensity vs. time data to calculate the mean Pb/U intensity ratio. Thus, the calculated intensity ratio and its uncertainty depend on the method applied. We demonstrate that the accuracy and, conditionally, the precision of the ratio-of-the-mean intensities method are invariant to the intensity fluctuations and averaging related to the dwell time selection and off-line data transformation (averaging of several sweeps); we present a statistical approach how to calculate the uncertainty of this method for transient signals. We also show that the accuracy of methods (2) and (3) is influenced by the intensity fluctuations and averaging, and the extent of this influence can amount to tens of percentage points; we show that the uncertainty of these methods also depends on how the signal is averaged. Each of the above methods imposes requirements to the instrumentation. The ratio-of-the-mean intensities method is sufficiently accurate provided the laser induced fractionation between the beginning and the end of the signal is kept low and linear. We show, based on a comprehensive series of analyses with different ablation pit sizes, energy densities and repetition rates for a 193 nm ns-ablation system that such a fractionation behaviour requires using a low ablation speed (low energy density and low repetition rate). Overall, we conclude that the ratio-of-the-mean intensities method combined with low sampling rates is the most mathematically accurate among the existing data treatment methods for U-Pb zircon dating by sensitive sector field ICPMS.

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EBV has been consistently associated with MS, but its signature in the CNS has rarely been examined. In this study, we assessed EBV-specific humoral and cellular immune responses in the cerebrospinal fluid (CSF) of patients with early MS, other inflammatory neurological diseases (OIND) and non-inflammatory neurological diseases (NIND). The neurotropic herpesvirus CMV served as a control. Virus-specific humoral immune responses were assessed in 123 consecutive patients and the intrathecal recruitment of virus-specific antibodies was expressed as antibody indexes. Cellular immune responses tested in the blood of 55/123 patients were positive in 46/55. The CD8(+) CTL responses of these 46 patients were assessed in the blood and CSF using a CFSE-based CTL assay. We found that viral capsid antigen and EBV-encoded nuclear antigen-1, but not CMV IgG antibody indexes, were increased in early MS as compared with OIND and NIND patients. There was also intrathecal enrichment in EBV-, but not CMV-specific, CD8(+) CTL in early MS patients. By contrast, OIND and NIND patients did not recruit EBV- nor CMV-specific CD8(+) CTL in the CSF. Our data, showing a high EBV-, but not CMV-specific intrathecal immune response, strengthen the association between EBV and MS, in particular at the onset of the disease.

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The relationship between protein profiles of Gluteus medius (GM) muscles of raw hams obtained from 4 pure breed pigs (Duroc, Large White, Landrace, and Piétrain) with the final quality of the Semimembranosus and Biceps femoris muscles of dry-cured hams was investigated. As expected, Duroc hams showed higher levels of marbling and intramuscular fat content than the other breeds. Piétrain hams were the leanest and most conformed, and presented the lowest salt content in dry-cured hams. Even if differences in the quality traits (colour, water activity, texture, composition, intramuscular fat, and marbling) of dry-cured hams were observed among the studied breeds, only small differences in the sensory attributes were detected. Surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (SELDI-TOF-MS) was used to obtain the soluble protein profiles of GM muscles. Some associations between protein peaks obtained with SELDI-TOF-MS and quality traits, mainly colour (b*) and texture (F0, Y2, Y90) were observed. Candidate protein markers for the quality of processed dry-cured hams were identified

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L’objectiu d’aquest estudi és determinar la zona més efectiva per guanyar el punt mitjançant l’atac de dreta en el tennis de taula. S’utilitza una adaptació del sistema d’anàlisi dels tres nivells d’habilitat, proposat pels acadèmics xinesos Wu i Li (1990) per tal de classificar els punts de la forma que ens permetin analitzar les zones de finalització i les formes com s’obtenen els punts. L’estudi analitza cinc partits dels sis millors jugadors del rànquing mundial de la ITTF. El resultat de l’estudi és que la zona de finalització més eficaç per obtenir el punt mitjançant l’atac de dreta és la zona 1 de la taula del rival.

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Segons Castelo (1999, 2009) i Ardá i Casal (2003) la fase ofensiva del futbol es divideix en la fase de progressió, en la qual es busca progressar a porteria, i en la fase de manteniment o emergència, en la qual s’assegura la possessió de la pilota. L’objectiu és analitzar si quan el davanter centre rep la pilota d’esquena a porteria, es manté amb més eficàcia la possessió jugant en progressió o en emergència durant els 5” posteriors a la recepció de la pilota per part del davanter. L’estudi és Descriptiu d’Observació Directa, en aquest s’observen i s’analitzen, a través de vídeos, 10 partits de la fase de grups de la fase final de la Eurocopa 2012, en concret els partits són dels grups A i B. Els resultats confirmen la hipòtesi inicial, ja que es manté amb més eficàcia la pilota quan aquesta es juga en emergència (71%) que no pas en progressió (54%).

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La situación actual del mercado y del sector de las nuevas tecnologías genera la necesidad de que las marcas y las empresas, se comuniquen como entes sociales y a través de medios como las aplicaciones móviles. El presente artículo presenta el análisis de 24 marcas que cuentan con aplicaciones móviles (apps). Se ha tomado en cuenta para ello, la valoración que los usuarios dan a las aplicaciones. Específicamente el estudio se centra en herramientas destinadas al dispositivo iPhone. Las apps, representan a las marcas la posibilidad de contar con un soporte más para comunicarse con sus públicos.

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Les vacances, el descans mensual, ens influeixen des del punt de vista psicològic i fisiològic, en vista de dos treballs científics recents que analitzen minuciosament els seus efectes.