168 research outputs found

    Análisis del impacto ambiental y económico vinculado a la energía fotovoltaica frente al uso de energías convencionales en el regadío

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    La energía fotovoltaica (fv) presenta un gran potencial para la agricultura en zonas con adecuados niveles de radiación. El principal inconveniente derivado de su uso como única fuente de energía radica en su dependencia de las variables climáticas. El desarrollo de sistemas de gestión inteligente del riego con energía fv minimiza este problema, consiguiendo satisfacer las necesidades del cultivo durante toda la campaña. Esto es posible gracias a la sincronización de la potencia fv generada con la demanda de potencia y tiempos de riego de la red. Así, el sistema resulta energéticamente independiente, lo que asegura una prácticamente nula emisión de contaminantes durante el periodo de funcionamiento, así como una evidente reducción en los costes de operación. Sin embargo, para valorar el impacto ambiental y económico vinculado a esta tecnología, es necesario contemplar los procesos de producción e instalación, así como los costes de inversión. Para ello, en este trabajo se ha llevado a cabo un análisis del ciclo de vida de un sistema de riego fv inteligente, comparándose además con las fuentes de energía tradicionalmente empleadas en riego. Se establecieron dos posibles escenarios: con y sin acceso a la red eléctrica, en los que el sistema de riego fv se evaluó frente al uso de un generador diésel y la red eléctrica, respectivamente, considerando una vida útil del proyecto de 30 años. El análisis de impacto ambiental se llevó a cabo siguiendo la metodología CML (Centre for Environmental Science- Leiden University), seleccionando 5 categorías de impacto como las más representativas: potencial de calentamiento global (Global Warming Potential- GWP), potencial de agotamiento de los recursos abióticos (Abiotic Resource Depletion Potential- ARDP), potencial de acidificación (Acidification Potential- AP), potencial de toxicidad humana (Human Toxicity Potential- HTP) y potencial de agotamiento de los recursos fósiles (Fuel Resources Depletion Potential- FRDP). Los resultados mostraron el riego fv como la opción con menor carga ambiental para todas las categorías, excepto para el ARDP, donde la demanda de materiales para la fabricación de los módulos solares y el inversor tuvo una importante repercusión. Por su parte, el sistema de riego fv presentó el mayor coste de inversión, aunque el menor coste total vinculado a toda la vida útil del proyecto, gracias al bajo coste asociado a la etapa de funcionamiento del sistema

    Fibrocytes in health and disease

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    Fibrocytes, a group of bone marrow-derived mesenchymal progenitor cells, were first described in 1994 as fibroblast-like, peripheral blood cells that migrate to regions of tissue injury. These cells are unique in their expression of extracellular matrix proteins concomitantly with markers of hematopoietic and monocyte lineage. The involvement of fibrocytes and the specific role they play in the process of wound repair has been a focus of study since their initial description. Fibrocytes contribute to the healing repertoire via several mechanisms; they produce a combination of cytokines, chemokines, and growth factors to create a milieu favorable for repair to occur; they serve as antigen presenting cells (APCs); they contribute to wound closure; and, they promote angiogenesis. Furthermore, regulatory pathways involving serum amyloid P, leukocyte-specific protein 1, and adenosine A2A receptors have emphasized the significant role that fibrocytes have in wound healing and fibrosis. The therapeutic targeting of fibrocytes holds promise for the augmentation of wound repair and the treatment of different fibrosing disorders

    Penalty-free feasibility boundary convergent multi-objective evolutionary algorithm for the optimization of water distribution systems

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    This paper presents a new penalty-free multi-objective evolutionary approach (PFMOEA) for the optimization of water distribution systems (WDSs). The proposed approach utilizes pressure dependent analysis (PDA) to develop a multi-objective evolutionary search. PDA is able to simulate both normal and pressure deficient networks and provides the means to accurately and rapidly identify the feasible region of the solution space, effectively locating global or near global optimal solutions along its active constraint boundary. The significant advantage of this method over previous methods is that it eliminates the need for ad-hoc penalty functions, additional “boundary search” parameters, or special constraint handling procedures. Conceptually, the approach is downright straightforward and probably the simplest hitherto. The PFMOEA has been applied to several WDS benchmarks and its performance examined. It is demonstrated that the approach is highly robust and efficient in locating optimal solutions. Superior results in terms of the initial network construction cost and number of hydraulic simulations required were obtained. The improvements are demonstrated through comparisons with previously published solutions from the literature

    Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

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    OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

    DAS-28-based EULAR response and HAQ improvement in rheumatoid arthritis patients switching between TNF antagonists

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    <p>Abstract</p> <p>Introduction</p> <p>No definitive data are available regarding the value of switching to an alternative TNF antagonist in rheumatoid arthritis patients who fail to respond to the first one. The aim of this study was to evaluate treatment response in a clinical setting based on HAQ improvement and EULAR response criteria in RA patients who were switched to a second or a third TNF antagonist due to failure with the first one.</p> <p>Methods</p> <p>This was an observational, prospective study of a cohort of 417 RA patients treated with TNF antagonists in three university hospitals in Spain between January 1999 and December 2005. A database was created at the participating centres, with well-defined operational instructions. The main outcome variables were analyzed using parametric or non-parametric tests depending on the level of measurement and distribution of each variable.</p> <p>Results</p> <p>Mean (± SD) DAS-28 on starting the first, second and third TNF antagonist was 5.9 (± 2.0), 5.1 (± 1.5) and 6.1 (± 1.1). At the end of follow-up, it decreased to 3.3 (± 1.6; Δ = -2.6; p > 0.0001), 4.2 (± 1.5; Δ = -1.1; p = 0.0001) and 5.4 (± 1.7; Δ = -0.7; p = 0.06). For the first TNF antagonist, DAS-28-based EULAR response level was good in 42% and moderate in 33% of patients. The second TNF antagonist yielded a good response in 20% and no response in 53% of patients, while the third one yielded a good response in 28% and no response in 72%. Mean baseline HAQ on starting the first, second and third TNF antagonist was 1.61, 1.52 and 1.87, respectively. At the end of follow-up, it decreased to 1.12 (Δ = -0.49; p < 0.0001), 1.31 (Δ = -0.21, p = 0.004) and 1.75 (Δ = -0.12; p = 0.1), respectively. Sixty four percent of patients had a clinically important improvement in HAQ (defined as ≥ -0.22) with the first TNF antagonist and 46% with the second.</p> <p>Conclusion</p> <p>A clinically significant effect size was seen in less than half of RA patients cycling to a second TNF antagonist.</p

    Predictive integration of gene functional similarity and co-expression defines treatment response of endothelial progenitor cells

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    <p>Abstract</p> <p>Background</p> <p>Endothelial progenitor cells (EPCs) have been implicated in different processes crucial to vasculature repair, which may offer the basis for new therapeutic strategies in cardiovascular disease. Despite advances facilitated by functional genomics, there is a lack of systems-level understanding of treatment response mechanisms of EPCs. In this research we aimed to characterize the EPCs response to adenosine (Ado), a cardioprotective factor, based on the systems-level integration of gene expression data and prior functional knowledge. Specifically, we set out to identify novel biosignatures of Ado-treatment response in EPCs.</p> <p>Results</p> <p>The predictive integration of gene expression data and standardized functional similarity information enabled us to identify new treatment response biosignatures. Gene expression data originated from Ado-treated and -untreated EPCs samples, and functional similarity was estimated with Gene Ontology (GO)-based similarity information. These information sources enabled us to implement and evaluate an integrated prediction approach based on the concept of <it>k</it>-nearest neighbours learning (<it>k</it>NN). The method can be executed by expert- and data-driven input queries to guide the search for biologically meaningful biosignatures. The resulting <it>integrated kNN </it>system identified new candidate EPC biosignatures that can offer high classification performance (areas under the operating characteristic curve > 0.8). We also showed that the proposed models can outperform those discovered by standard gene expression analysis. Furthermore, we report an initial independent <it>in vitro </it>experimental follow-up, which provides additional evidence of the potential validity of the top biosignature.</p> <p>Conclusion</p> <p>Response to Ado treatment in EPCs can be accurately characterized with a new method based on the combination of gene co-expression data and GO-based similarity information. It also exploits the incorporation of human expert-driven queries as a strategy to guide the automated search for candidate biosignatures. The proposed biosignature improves the systems-level characterization of EPCs. The new integrative predictive modeling approach can also be applied to other phenotype characterization or biomarker discovery problems.</p

    Physicochemical and biological characterization of 1E10 Anti-Idiotype vaccine

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    <p>Abstract</p> <p>Background</p> <p>1E10 monoclonal antibody is a murine anti-idiotypic antibody that mimics N-glycolyl-GM3 gangliosides. This antibody has been tested as an anti-idiotypic cancer vaccine, adjuvated in Al(OH)<sub>3</sub>, in several clinical trials for melanoma, breast, and lung cancer. During early clinical development this mAb was obtained <it>in vivo </it>from mice ascites fluid. Currently, the production process of 1E10 is being transferred from the <it>in vivo </it>to a bioreactor-based method.</p> <p>Results</p> <p>Here, we present a comprehensive molecular and immunological characterization of 1E10 produced by the two different production processes in order to determine the impact of the manufacturing process in vaccine performance. We observed differences in glycosylation pattern, charge heterogeneity and structural stability between <it>in vivo</it>-produced 1E10 and bioreactor-obtained 1E10. Interestingly, these modifications had no significant impact on the immune responses elicited in two different animal models.</p> <p>Conclusions</p> <p>Changes in 1E10 primary structure like glycosylation; asparagine deamidation and oxidation affected 1E10 structural stability but did not affect the immune response elicited in mice and chickens when compared to 1E10 produced in mice.</p

    Non-adenine based purines accelerate wound healing

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    Wound healing is a complex sequence of cellular and molecular processes that involves multiple cell types and biochemical mediators. Several growth factors have been identified that regulate tissue repair, including the neurotrophin nerve growth factor (NGF). As non-adenine based purines (NABPs) are known to promote cell proliferation and the release of growth factors, we investigated whether NABPs had an effect on wound healing. Full-thickness, excisional wound healing in healthy BALB/c mice was significantly accelerated by daily topical application of NABPs such as guanosine (50% closure by days 2.5′.8). Co-treatment of wounds with guanosine plus anti-NGF reversed the guanosine-promoted acceleration of wound healing, indicating that this effect of guanosine is mediated, at least in part, by NGF. Selective inhibitors of the NGF-inducible serine/threonine protein kinase (protein kinase N), such as 6-methylmercaptopurine riboside abolished the acceleration of wound healing caused by guanosine, confirming that activation of this enzyme is required for this effect of guanosine. Treatment of genetically diabetic BKS.Cg-m+/+lepr db mice, which display impaired wound healing, with guanosine led to accelerated healing of skin wounds (25% closure by days 2.8′.0). These results provide further confirmation that the NABP-mediated acceleration of cutaneous wound healing is mediated via an NGF-dependent mechanism. Thus, NABPs may offer an alternative and viable approach for the treatment of wounds in a clinical setting
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