107 research outputs found

    Harish-Chandra integrals as nilpotent integrals

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    Recently the correlation functions of the so-called Itzykson-Zuber/Harish-Chandra integrals were computed (by one of the authors and collaborators) for all classical groups using an integration formula that relates integrals over compact groups with respect to the Haar measure and Gaussian integrals over a maximal nilpotent Lie subalgebra of their complexification. Since the integration formula a posteriori had the same form for the classical series, a conjecture was formulated that such a formula should hold for arbitrary semisimple Lie groups. We prove this conjecture using an abstract Lie-theoretic approach.Comment: 10 page

    Prostate Diffusion Weighted-Magnetic Resonance Image analysis using Multivariate Curve Resolution methods

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    [EN] Multivariate Curve Resolution (MCR) has been applied on prostate Diffusion Weighted-Magnetic Resonance Images (DW-MRI). Different physiological-based modeling approaches of the diffusion process have been submitted to validation by sequentially incorporating prior knowledge on the MCR constraints. Results validate the biexponential diffusion modeling approach and show the capability of the MCR models to find, characterize and locate the behaviors related to the presence of an early prostate tumor.The authors want to thank prof. Anna de Juan for her comments and help in using the software for this study. This research work was partially supported by the Spanish Ministry of Economy and Competitiveness under the project DPI 2011-28112-004-02.Aguado Sarri贸, E.; Prats-Montalb谩n, JM.; Sanz Requena, R.; Marti Bonmati, L.; Alberich Bayarri, 脕.; Ferrer Riquelme, AJ. (2015). Prostate Diffusion Weighted-Magnetic Resonance Image analysis using Multivariate Curve Resolution methods. Chemometrics and Intelligent Laboratory Systems. 140:43-48. https://doi.org/10.1016/j.chemolab.2014.11.002S434814

    Tomato UDP-glucose sterol glycosyltransferases: A family of developmental and stress regulated genes that encode cytosolic and membrane-associated forms of the enzyme

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    Sterol glycosyltransferases (SGTs) catalyze the glycosylation of the free hydroxyl group at C-3 position of sterols to produce sterol glycosides. Glycosylated sterols and free sterols are primarily located in cell membranes where in combination with other membrane-bound lipids play a key role in modulating their properties and functioning. In contrast to most plant species, those of the genus Solanum contain very high levels of glycosylated sterols, which in the case of tomato may account for more than 85% of the total sterol content. In this study, we report the identification and functional characterization of the four members of the tomato (Solanum lycopersicum cv. Micro-Tom) SGT gene family. Expression of recombinant SlSGT proteins in E. coli cells and N. benthamiana leaves demonstrated the ability of the four enzymes to glycosylate different sterol species including cholesterol, brassicasterol, campesterol, stigmasterol, and 尾-sitosterol, which is consistent with the occurrence in their primary structure of the putative steroid-binding domain found in steroid UDP-glucuronosyltransferases and the UDP-sugar binding domain characteristic for a superfamily of nucleoside diphosphosugar glycosyltransferases. Subcellular localization studies based on fluorescence recovery after photobleaching and cell fractionation analyses revealed that the four tomato SGTs, like the Arabidopsis SGTs UGT80A2 and UGT80B1, localize into the cytosol and the PM, although there are clear differences in their relative distribution between these two cell fractions. The SlSGT genes have specialized but still largely overlapping expression patterns in different organs of tomato plants and throughout the different stages of fruit development and ripening. Moreover, they are differentially regulated in response to biotic and abiotic stress conditions. SlSGT4 expression increases markedly in response to osmotic, salt, and cold stress, as well as upon treatment with abscisic acid and methyl jasmonate

    Nerolidol production in agroinfiltrated tobacco: Impact of protein stability and membrane targeting of strawberry (Fragraria ananassa) NEROLIDOL SYNTHASE1

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    The sesquiterpene alcohol nerolidol, synthesized from farnesyl diphosphate (FDP), mediates plant-insect inter- actions across multiple trophic levels with major implications for pest management in agriculture. We compared nerolidol engineering strategies in tobacco using agroinfiltration to transiently express strawberry (Fragraria ananassa) linalool/nerolidol synthase (FaNES1) either at the endoplasmic reticulum (ER) or in the cytosol as a soluble protein. Using solid phase microextraction and gas chromatography-mass spectrometry (SPME-GCMS), we have determined that FaNES1 directed to the ER via fusion to the transmembrane domain of squalene synthase or hydroxymethylglutaryl - CoA reductase displayed significant improvements in terms of transcript levels, protein accumulation, and volatile production when compared to its cytosolic form. However, the highest levels of nerolidol production were observed when FaNES1 was fused to GFP and expressed in the cytosol. This SPME-GCMS method afforded a limit of detection and quantification of 1.54 and 5.13 pg, respectively. Nerolidol production levels, which ranged from 0.5 to 3.0 渭g/g F.W., correlated more strongly to the accumulation of recombinant protein than transcript level, the former being highest in FaNES-GFP transfected plants. These results indicate that while the ER may represent an enriched source of FDP that can be exploited in metabolic engineering, protein accumulation is a better predictor of sesquiterpene production

    A matrix model for the topological string II: The spectral curve and mirror geometry

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    In a previous paper, we presented a matrix model reproducing the topological string partition function on an arbitrary given toric Calabi-Yau manifold. Here, we study the spectral curve of our matrix model and thus derive, upon imposing certain minimality assumptions on the spectral curve, the large volume limit of the BKMP "remodeling the B-model" conjecture, the claim that Gromov-Witten invariants of any toric Calabi-Yau 3-fold coincide with the spectral invariants of its mirror curve.Comment: 1+37 page

    Valoraci贸n de una Encuesta sobre Servicios de Atenci贸n Farmac茅utica a Farmac茅uticos de Alicante

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    INTRODUCCI脫N: Hay descritas barreras y facilitadores para implantar la AF. Algunos facilitadores podr铆an ser proporcionados desde los colegios profesionales. OBJETIVO: Conocer el inter茅s de los farmac茅uticos comunitarios alicantinos por los servicios de AF, y sus preferencias para implantar/mejorar 茅stos. M脡TODO: Estudio transversal realizado marzo-mayo de 2012, mediante un cuestionario an贸nimo a todos los colegiados ejercientes en OF, consensuado por la comisi贸n de AF del COFA, disponible en la web colegial 70 d铆as. Con preguntas referentes聽a su implantaci贸n, protocolizaci贸n, registros, evaluaci贸n y ayudas sugeridas para su implantaci贸n/mejora. 聽 RESULTADOS: Respondieron 19,9% de los colegiados ejercientes en FC, afirmando la mayor铆a querer mejorar su trabajo. Siguen protocolos para IF el 58%, automedicaci贸n un 60% y 33% para dispensaci贸n con receta. Realizan SFT un 23% y SPD 15%. La mayor铆a no registra las actuaciones, siendo 77% en IF, 70% en automedicaci贸n, 78% dispensaci贸n con receta,聽excepto SFT con 25%. Como formato de registro, se prefiere papel, excepto en SFT que son aplicaciones inform谩ticas. La mayor铆a eval煤a el resultado en ocasiones, solo un 8% lo hace siempre. En SFT lo eval煤an siempre un 29%. Se prefiere un servicio de informaci贸n frente a dudas, seguido de uno de apoyo a la implantaci贸n. CONCLUSIONES: Existe inter茅s entre los farmac茅uticos alicantinos por la AF. Ser铆a deseable un mayor grado de implantaci贸n de estos servicios, existiendo gran recorrido de mejora en la protocolizaci贸n, el registro y la evaluaci贸n de los resultados. Como聽herramientas para ello, destaca la solicitud al colegio de un servicio de informaci贸n frente a dudas

    Valoraci贸n de una Encuesta sobre Servicios de Atenci贸n Farmac茅utica a Farmac茅uticos de Alicante

    Get PDF
    INTRODUCCI脫N: Hay descritas barreras y facilitadores para implantar la AF. Algunos facilitadores podr铆an ser proporcionados desde los colegios profesionales. OBJETIVO: Conocer el inter茅s de los farmac茅uticos comunitarios alicantinos por los servicios de AF, y sus preferencias para implantar/mejorar 茅stos. M脡TODO: Estudio transversal realizado marzo-mayo de 2012, mediante un cuestionario an贸nimo a todos los colegiados ejercientes en OF, consensuado por la comisi贸n de AF del COFA, disponible en la web colegial 70 d铆as. Con preguntas referentes聽a su implantaci贸n, protocolizaci贸n, registros, evaluaci贸n y ayudas sugeridas para su implantaci贸n/mejora. 聽 RESULTADOS: Respondieron 19,9% de los colegiados ejercientes en FC, afirmando la mayor铆a querer mejorar su trabajo. Siguen protocolos para IF el 58%, automedicaci贸n un 60% y 33% para dispensaci贸n con receta. Realizan SFT un 23% y SPD 15%. La mayor铆a no registra las actuaciones, siendo 77% en IF, 70% en automedicaci贸n, 78% dispensaci贸n con receta,聽excepto SFT con 25%. Como formato de registro, se prefiere papel, excepto en SFT que son aplicaciones inform谩ticas. La mayor铆a eval煤a el resultado en ocasiones, solo un 8% lo hace siempre. En SFT lo eval煤an siempre un 29%. Se prefiere un servicio de informaci贸n frente a dudas, seguido de uno de apoyo a la implantaci贸n. CONCLUSIONES: Existe inter茅s entre los farmac茅uticos alicantinos por la AF. Ser铆a deseable un mayor grado de implantaci贸n de estos servicios, existiendo gran recorrido de mejora en la protocolizaci贸n, el registro y la evaluaci贸n de los resultados. Como聽herramientas para ello, destaca la solicitud al colegio de un servicio de informaci贸n frente a dudas

    MCR-ALS on metabolic networks: Obtaining more meaningful pathways

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    [EN] With the aim of understanding the flux distributions across a metabolic network, i.e. within living cells, Principal Component Analysis (PCA) has been proposed to obtain a set of orthogonal components (pathways) capturing most of the variance in the flux data. The problems with this method are (i) that no additional information can be included in the model, and (ii) that orthogonality imposes a hard constraint, not always reasonably. To overcome these drawbacks, here we propose to use a more flexible approach such as Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) to obtain this set of biological pathways through the network. By using this method, different constraints can be included in the model, and the same source of variability can be present in different pathways, which is reasonable from a biological standpoint. This work follows a methodology developed for Pichia pastoris cultures grown on different carbon sources, lately presented in Gonz谩lez-Mart铆nez et al. (2014). In this paper a different grey modelling approach, which aims to incorporate a priori knowledge through constraints on the modelling algorithms, is applied to the same case of study. The results of both models are compared to show their strengths and weaknesses.Research in this study was partially supported by the Spanish Ministry of Science and Innovation and FEDER funds from the European Union through grants DPI2011-28112-C04-01 and DPI2011-28112-C04-02. The authors are also grateful to Biopolis SL for supporting this research.Folch-Fortuny, A.; Tortajada Serra, M.; Prats-Montalb谩n, JM.; Llaneras Estrada, F.; Pic贸 Marco, JA.; Ferrer Riquelme, AJ. (2015). MCR-ALS on metabolic networks: Obtaining more meaningful pathways. Chemometrics and Intelligent Laboratory Systems. 142:293-303. https://doi.org/10.1016/j.chemolab.2014.10.004S29330314

    Effect of the haematocrit layer geometry on Plasmodium falciparum static thin-layer in vitro cultures

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    <p>Abstract</p> <p>Background</p> <p><it>In vitro </it>cultivation of <it>Plasmodium falciparum </it>is usually carried out through the continuous preservation of infected erythrocytes deposited in static thin layers of settled haematocrit. This technique, called the candle-jar method, was first achieved by Trager and Jensen in 1976 and has undergone slight modifications since then. However, no systematic studies concerning the geometry of the haematocrit layer have been carried out. In this work, a thorough investigation of the effects of the geometric culturing conditions on the parasite's development is presented.</p> <p>Methods</p> <p>Several experimental trials exploring different settings have been carried out, covering haematocrit layer depths that ranged from 6 mm to 3 mm and separation between the walls of the culturing device that ranged from 7.5 mm to 9 mm. The obtained results have been analysed and compared to different system-level models and to an Individual-Based Model.</p> <p>Conclusion</p> <p>In line with the results, a mechanism governing the propagation of the infection which limits it to the vicinity of the interface between the haematocrit layer and the culture medium is deduced, and the most appropriate configurations are proposed for further experimental assays.</p
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