172 research outputs found

    Una contribución al registrado articulado: aplicación a la determinación de la maduración ósea mediante análisis de imágenes radiográficas

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    Este trabajo se plantea de un modo inédito de registrado elástico de imágenes médicas llamado “registrado articulado”. Está basado en un modelo anatómico formado por puntos de control anatómicos conectados entre sí en el que cada hueso es registrado de forma afín y los tejidos blandos son registrados de forma elástica, manteniendo las estructuras óseas largas rectas mientras que la transformación a lo largo de toda la imagen es continua y suave. Se aplica el método articulado en el registrado de radiografías de la mano superando a otros métodos alternativos. Además hemos generalizado al marco de registrado poliafín Log-Euclídeo de forma que permita estructuras articuladas. Se propone también una metodología inédita basada en registrado de imagen para determinar de forma automática la edad ósea siguiendo el método TW3. Este método realiza el registrado de la radiografía de la mano como un paso previo. Proponemos dos clasificadores diferentes y comparamos sus resultados con los diagnósticos realizados por dos especialistas pediátricos; la metodología seguida nos lleva a la conclusión de que nuestro método automático obtiene resultados comparables a los diagnósticos inter-observador.Departamento de Teoría de la Señal y Comunicaciones e Ingenieria Telemátic

    Simulation of a biorefinery process as learning tool in chemical engineering degree

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    Currently, the search for alternative biomass to be used as renewable sources for energy production is one of the most important challenges to achieve a sustainable growth based on a bioeconomy strategy (Mendes et al., 2009). In this context, lignocellulosic waste are a renewable, clean, inexpensive and with high availability for the manufacture of biofuels. In this sense, the main objective of this study was the simulation and design of engineering processes that allows the valorization of lignocellulosic waste and the obtaining of biofuels as alternative to fossil fuels. This goal implies the practical application of the theoretical knowledge acquired by the student during the chemical engineering degree. Specifically, the students designed and simulated a biorefinery process that consisted of a Kraft pulping process as starting point of two main lines of production: (1) Process I: production of bioethanol and (2) Process II: direct and indirect production of dimethylether (DME), both from lignocellulosic biomass (Fig.1). Two commercial simulation packages, ASPEN HYSYS® and UNISIM were used to simulate the production of dimethylether and bioethanol, respectively. The first step was determining a strategic situation for the installation of the biorefinery. The central area of Andalusia (between the municipalities of Lucena and Antequera) was considered the most adequate area to develop the installation of the biorefinery plant after evaluating the biomass available inside of 100 kms of distance around this place. Specifically, different biomass mixtures were considered in order to ensure the viability of a constant inlet flow of biomass in the biorefinery. In function of this inlet flow of biomass, the installations were designed and dimensioned in each stage of the process. The student carried out a wide revision of state of the art to decide the most adequate processes among different alternatives to obtain dimethylether and bioethanol. The different stages selected as the most adequate in each line of the process can be observed in Fig.1. Moreover, the students evaluated the different alternatives for the valorisation and optimization of the by-products generated in each stage of the process in order to minimize the consuming of chemical compounds and energy requirements. Therefore, the students learnt to develop a real engineering process more sustainable and friendly with the environment. To sum up, the used of programs to simulate the transformation of lignocellulosic biomass in biofuels, such as, bioethanol or dimethylether, which is a process with several social, environmental and economic advantages, was an interesting learning tool for students of chemical engineering degree. Keywords Bioethanol, design, dimethylether, Kraft pulping process, simulations. References Mendes, C.V.T., Carvalho, M.G.V.S., Baptista, C.M.S.G., Rocha, J.M.S., Soares, B.I.G., Sousa, G.D.A., 2009. Valorisation of hardwood hemicelluloses in the kraft pulping process by using an integrated biorefinery concept. Food Bioproduct Process 87:197–207.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech MINECO: Proyecto CTQ2015-68654-

    Bentonite powder XRD quantitative analysis using Rietveld refinement: Revisiting and updating bulk semiquantitative mineralogical compositions

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    Bentonite is a claystone formed by a complex mineralogical mixture, composed of mont-morillonite, illite, and accessory minerals like quartz, cristobalite, feldspars, carbonates, and minor amounts of iron oxy-hydroxides. Bentonite presents complexity at various scales: (1): a single mineral may present different chemical composition within the same quarry (e.g., feldspars solid solu-tions); (2): montmorillonite presents variability in the cation-exchange distribution while illite may be presented as mixed-layer with smectite sheets; and (3): hardness and crystal size are larger in accessory minerals than in clay minerals, preventing uniform grinding of bentonite. The FEBEX bentonite used is originally from Almería (Spain), and it is a predominantly calcium, magnesium, and sodium bentonite. This Spanish FEBEX bentonite has been hydrothermally altered at laboratory scale for 7–14 years. A thermal gradient was generated by heating a disk of pressed iron powder, simulating the metal waste canister, in contact with the compacted bentonite sample. Hydration was forced from the opposite direction. XRD recorded patterns were very similar. In order to min-imize the bias of XRD semi-quantitative determination methods, Rietveld refinement was per-formed using BGMN software and different structural models. Confidence in the quantification of the main phases allows us to convincingly detect other subtle changes such as the presence of calcite in the hydration front, right at the interface between the saturated and unsaturated bentonite, or the presence of goethite, and not hematite, in the saturated bentonite, near the source of hydration. Smectite component was 72 ± 3% and the refinement was consistent with the presence of ~10% illite, comparable with previous characterization

    Maternal Dietary Patterns during Pregnancy and Their Association with Gestational Weight Gain and Nutrient Adequacy.

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    Several epidemiologic studies have shown an association between Gestational Weight Gain (GWG) and offspring complications. The GWG is directly linked to maternal dietary intake and women's nutritional status during pregnancy. The aim of this study was (1) to assess, in a sample of Spanish pregnant women, the association between maternal dietary patterns and GWG and (2) to assess maternal dietary patterns and nutrient adequate intake according to GWG. A retrospective study was conducted in a sample of 503 adult pregnant women in five hospitals in Eastern Andalusia (Spain). Data on demographic characteristics, anthropometric values, and dietary intake were collected from clinical records by trained midwives. Usual food intake was gathered through a validated Food Frequency Questionnaire (FFQ), and dietary patterns were obtained by principal component analysis. Nutrient adequacy was defined according to European dietary intake recommendations for pregnant women. Regression models adjusted by confounding factors were constructed to study the association between maternal dietary pattern and GWG, and maternal dietary patterns and nutritional adequacy. A negative association was found between GWG and the Mediterranean dietary pattern (crude β = -0.06, 95% CI: -0.11, -0.04). Independent of maternal dietary pattern, nutrient adequacy of dietary fiber, vitamin B9, D, E, and iodine was related to a Mediterranean dietary pattern (p < 0.05). A Mediterranean dietary pattern is related to lower GWG and better nutrient adequacy. The promotion of healthy dietary behavior consistent with the general advice promoted by the Mediterranean Diet (based on legumes, vegetables, nuts, olive oil, and whole cereals) will offer healthful, sustainable, and practical strategies to control GWG and ensure adequate nutrient intake during pregnancy

    Polysialylated neuropilin-2 enhances human dendritic cell migration through the basic C-terminal region of CCL21.

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    Free Access at: http://glycob.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=20488940Dendritic cell (DC) migration to secondary lymphoid organs is a critical step to properly exert its role in immunity; and predominantly depends on the interaction of the chemokine receptor CCR7 with its ligands CCL21 and CCL19. Polysialic acid (PSA) has been recently reported to control CCL21-directed migration of mature DCs. Here; we first demonstrate that PSA present on human mature monocyte-derived dendritic cells did not enhance chemotactic responses to CCL19. We have also explored the molecular mechanisms underlying the selective enhancing effect of PSA on CCL21-driven chemotaxis of DCs. In this regard; we found out that prevention of DC polysialylation decreased CCL21 activation of JNK and Akt signaling pathways; both associated with CCR7-mediated chemotaxis. We also report that the enhanced PSA-mediated effect on DC migration towards CCL21 relied on the highly basic C-terminal region of this chemokine; and depended on the PSA acceptor molecule neuropilin-2 (NRP2) and on the polysialyltransferase ST8SiaIV. Altogether; our data indicate that the CCR7/CCL21/NRP2/ST8SiaIV functional axis constitutes an important guidance clue for DC targeting to lymphoid organs.This work was supported by research grant from Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo (FISPI0708879 to MAV).Peer reviewe

    Convolution-based free-form deformation for multimodal groupwise registration

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    Producción CientíficaRecently, an efficient implementation of convolution-based free form deformations (FFD) has been proposed for both groupwise 3D monomodal and 2D pairwise multimodal registrations. However, there is still an unmet need in the field for groupwise -D multimodal registration with L > 2. In this correspondence, we address this need and present a solution for achieving accurate registration using two popular metrics: Renyi entropy and PCA2.Ministerio de Economía, Industria y Competitividad (TEC2017-82408-R and PID2020-115339RB-I00)ESAOTE Ltd. (18IQBM

    Efficient convolution-based pairwise elastic image registration on three multimodal similarity metrics

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    Producción CientíficaThis paper proposes a complete convolutional formulation for 2D multimodal pairwise image registration problems based on free-form deformations. We have reformulated in terms of discrete 1D convolutions the evaluation of spatial transformations, the regularization term, and their gradients for three different multimodal registration metrics, namely, normalized cross correlation, mutual information, and normalized mutual information. A sufficient condition on the metric gradient is provided for further extension to other metrics. The proposed approach has been tested, as a proof of concept, on contrast-enhanced first-pass perfusion cardiac magnetic resonance images. Execution times have been compared with the corresponding execution times of the classical tensor product formulation, both on CPU and GPU. The speed-up achieved by using convolutions instead of tensor products depends on the image size and the number of control points considered, the larger those magnitudes, the greater the execution time reduction. Furthermore, the speed-up will be more significant when gradient operations constitute the major bottleneck in the optimization process.Ministerio de Economía, Industria y Competitividad (grants TEC2017-82408-R and PID2020-115339RB-I00)ESAOTE Ltd (grant 18IQBM

    Therapeutic Potential of EWSR1-FLI1 Inactivation by CRISPR/Cas9 in Ewing Sarcoma.

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    Ewing sarcoma is an aggressive bone cancer affecting children and young adults. The main molecular hallmark of Ewing sarcoma are chromosomal translocations that produce chimeric oncogenic transcription factors, the most frequent of which is the aberrant transcription factor EWSR1-FLI1. Because this is the principal oncogenic driver of Ewing sarcoma, its inactivation should be the best therapeutic strategy to block tumor growth. In this study, we genetically inactivated EWSR1-FLI1 using CRISPR-Cas9 technology in order to cause permanent gene inactivation. We found that gene editing at the exon 9 of FLI1 was able to block cell proliferation drastically and induce senescence massively in the well-studied Ewing sarcoma cell line A673. In comparison with an extensively used cellular model of EWSR1-FLI1 knockdown (A673/TR/shEF), genetic inactivation was more effective, particularly in its capability to block cell proliferation. In summary, genetic inactivation of EWSR1-FLI1 in A673 Ewing sarcoma cells blocks cell proliferation and induces a senescence phenotype that could be exploited therapeutically. Although efficient and specific in vivo CRISPR-Cas9 editing still presents many challenges today, our data suggest that complete inactivation of EWSR1-FLI1 at the cell level should be considered a therapeutic approach to develop in the future.This research was funded by the Instituto de Salud Carlos III, grant numbers PI20CIII/00020, DTS18CIII/00005, PI16CIII/00026; Asociación Pablo Ugarte, grant numbers TRPV205/18, TPI-M 1149/13; Asociación Candela Riera, Asociación Todos Somos Iván & Fundación Sonrisa de Alex, grant numbers TVP333-19, TVP-1324/15; ASION, grant number TVP141/17, and by the Spanish Center for Biomedical Network Research on Rare Diseases (CIBERER, ER19P5AC728/2021, grant to M.M.), and by the Regional Government of Madrid (CAM, B2017/BMD3721, grant to M.A.M.-P.). R.M.M-F.d.M. was supported by a grant from the Spanish Center for Biomedical Network Research on Rare Diseases (CIBERER).S
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