262 research outputs found
Efecto de las estelas en los parques eólicos
Para el diseño de parques eólicos es de interés conocer la producción de energía eléctrica de las turbinas eólicas, o aeroturbinas, así como las cargas que pueden sufrir las mismas limitando su vida útil. La producción de energía está ligada a la intensidad del viento incidente, y la vida útil de las aeroturbinas al grado de agitación turbulenta del viento. El grupo de Mecánica de Fluidos Aplicado a la Ingeniería Industrial de la UPM, ha desarrollado programas informáticos para estimar la magnitud del viento y la intensidad de la turbulencia, en función de las características del terreno y de la distribución de las turbinas en el parque eólico, utilizando para ello modelos numéricos que simulan el movimiento turbulento de los fluidos
Efectos topográficos en el recurso eólico.
Para el diseño de parques eólicos es de interés conocer la producción de energía eléctrica de las turbinas eólicas, o aeroturbinas, así como las cargas que pueden sufrir las mismas limitando su vida útil. La producción de energía está ligada a la intensidad del viento incidente, y la vida útil de las aeroturbinas al grado de agitación turbulenta del viento. El grupo de Mecánica de Fluidos Aplicado a la Ingeniería Industrial de la UPM, ha desarrollado programas informáticos para estimar la magnitud del viento y la intensidad de la turbulencia, en función de las características del terreno y de la distribución de las turbinas en el parque eólico, utilizando para ello modelos numéricos que simulan el movimiento turbulento de los fluido
Study of isolated wakes and their superposition in wind farms, using different turbulence models
Different models to simulate wakes in wind farms are reviewed [1], [2]. Special emphasis is put in those elaborated by the authors. First, kinematic models, based on self-similar velocity deficit profiles and global momentum conservation, are briefly revisited. Then, field models of a different degree of complexity, which solve numerically the flow equations with several types of simplifications and turbulence closure models, are analyzed and compared. Models like Ainslie´s that uses a simple algebraic expression for the eddy viscosity, and are still widely used, are compared to other more complete models like UPMWAKE, which uses a k-ε turbulence closure. Ground effect, simulation of atmospheric conditions, atmospheric stability, simulation of turbulence characteristics, wake superposition and computer time consumed, will be used as terms of comparison. Results of an algebraic Reynolds Stress Model will also be presented, and compared with those of the k-ε turbulence closure. Then a comparison will follow of elliptic and parabolic models, and how boundary conditions at the disk are imposed. A discussion on the displacement of the wake origin for parabolic models will be made. The simplicity and computer time consumed to simulate wake superposition in whole large wind farms of the elliptic and parabolic models will be analyzed and compared. Results of a large eddy simulation model will also be presented and compared to those of previously mentioned models [3]. Wake meandering, and its role in wake turbulence generation when using simpler eddy viscosity models will be analyzed, and compared with other mechanisms of turbulence generation. The possibility and convenience of introducing unsteady terms in parabolic field models of wind farms, like UPMPARK, and thus simulate wake meandering will be discussed. Results of UPMPARK with and without meandering will be compared with available experimental data
Self-rated health status and cardiorespiratory fitness in a sample of schoolchildren from Bogotá, Colombia. The FUPRECOL study
To evaluate the relationship between Self-Rated Health (SRH) and cardiorespiratory fitness (CRF) in a sample of children and adolescents enrolled in official schools in Bogotá, Colombia. A cross-sectional study was performed with 7402 children and adolescents between 9 and 17 years of age. Participants were asked to rate their health based on eight validated questions, addressing the participants propensity for headache, stomach-ache, backache, feeling-low, irritability/bad mood, nervousness, sleeping-difficulties, and dizziness. The choices were “rarely or never”, “almost every month”, “almost every week”, and “more than once a week/about every day”. Participants performed the international course-navette shuttle run test to estimate CRF, and cut-off points for age and gender were used to categorize the healthy/unhealthy fitness zone according to the FITNESSGRAM® criteria. Overall, 16.4% of those surveyed reported a perception of irritability/bad mood “more than once a week/about every day”, followed by feeling-low and nervousness (both with 9.9%). Dizziness had the lowest prevalence with a percentage of 6.9%. Unhealthy CRF in boys increased the likelihood of headaches by 1.20 times, stomach aches by 1.31 times, feeling-low by 1.29 times, nervousness by 1.24 times, and dizziness by 1.29 times. In girls, unhealthy CRF increased the likelihood of headaches by 1.19 times, backache by 1.26 times, feeling-low by 1.28 times, irritability/bad mood by 1.17 times, sleeping-difficulties by 1.20 times, and dizziness by 1.27 times. SRH was associated with CRF in both genders. Early identification of children and adolescents with low CRF levels will permit interventions to promote healthy behaviors and prevent future diseases during adulthood. © 2017 by the authors. Licensee MDPI, Basel, Switzerland
A 3’-UTR polymorphism in soluble epoxide hydrolase gene Is associated with acute rejection in renal transplant recipients
Antecedentes y finalidad:
Los ácidos epoxyeicosatrienoic (EETs) son metabolitos del ácido araquidónico que desempeñan una función protectora contra procesos perjudiciales que pueden ocurrir después de re-oxigenación del injerto. Decidimos investigar si la presencia de polimorfismos funcionales en el gen que codifica el epóxido hidrolasa soluble (EPHX2), que metaboliza EETs a menos compuestos activos, pueden jugar un papel importante en el resultado del trasplante renal.
Métodos
En un grupo de 259 receptores caucásicos de trasplante renal y 183 donantes fallecidos, se determinó la presencia de tres EPHX2 común, a saber, los SNPs rs41507953 (K55R), rs751141 (R287Q) y rs1042032 A/G. Las asociaciones con los parámetros de la función del injerto y la incidencia de rechazo agudo fueron investigados retrospectivamente durante el primer año después del injerto mediante regresión logística, ajustándose a las variables clínicas y demográficas.
Resultados
Los portadores del genotipo rs1042032 GG muestran significativamente menor tasa de filtración glomerular estimada (eGFR) (38.15 ± 15.57 vs. 45.99 ± 16.05; p = 0,04) y mayores valores de creatinina sérica (1,57 ± 0,58 vs. 1,30 ± 0,47 g/dL; p=0.02) un año después del injerto, en comparación con los pacientes portadores del alelo A wildtype. El mismo genotipo GG también se asoció a un mayor riesgo de rechazo agudo. Curiosamente, esta asociación fue observada por el genotipo de ambos destinatarios [o =6.34 (1.35-29.90); p = 0,015] y donantes [OR = 5.53 (1.10 - 27.80); p=0,042]. Un modelo estadístico incluyendo ambos genotipos junto con otras variables demográficas y clínicas significativas se tradujo en un aumento de la importancia de la asociación con los receptores del genotipo [OR=8,28 (1.21-74.27); p=0,031].
Conclusiones
Nuestros resultados indican que la variabilidad genética en el gen metabolizante de EETs, EPHX2, pueden tener un impacto significativo en los resultados del trasplante renal de donante fallecido.Background and Purpose:
Epoxyeicosatrienoic acids (EETs) are arachidonic acid metabolites that play a protective
role against damaging processes that may occur after re-oxygenation of the graft. We
aimed to investigate whether the presence of functional polymorphisms in the gene encoding soluble epoxy hydrolase (EPHX2), which metabolizes EETs to less active compounds, may play a role in the outcome of renal transplantation.
Methods
In a group of 259 Caucasian renal transplant recipients and 183 deceased donors, we determined the presence of three common EPHX2 SNPs, namely rs41507953 (K55R), rs751141 (R287Q) and rs1042032 A/G. Associations with parameters of graft function and the incidence of acute rejection were retrospectively investigated throughout the first year after grafting by logistic regression adjusting for clinical and demographic variables.
Results
Carriers of the rs1042032 GG genotype displayed significantly lower estimated glomerular filtration rate (eGFR) (38.15 ± 15.57 vs. 45.99 ± 16.05; p = 0.04) and higher serum creatinine values (1.57 ± 0.58 vs. 1.30 ± 0.47 g/dL; p=0.02) one year after grafting, compared to patients carrying the wildtype A-allele. The same GG genotype was also associated to increased risk of acute rejection. Interestingly, this association was observed for the genotype of both recipients [OR =6.34 (1.35-29.90); p = 0.015] and donors [OR = 5.53 (1.10- 27.80); p=0.042]. A statistical model including both genotypes along with other meaningful demographic and clinical variables resulted in an increased significance for the association with the recipients’ genotype [OR=8.28 (1.21-74.27); p=0.031].
Conclusions
Our results suggest that genetic variability in the EETs-metabolizing gene, EPHX2, may
have a significant impact on the outcome of deceased-donor renal transplantation.• Asociación para el Estudio y la Prevención de las Enfermedades Renales (ASEPER), Badajoz
• Junta de Extremadura, Consejería de Economía, Comercio e Innovación: Proyecto GR10022
• Red de Investigación Renal - REDINREN (Instituto de Salud Carlos III – Fondo Europeo de Desarrollo Regional – FEDER) : Ayudas a Eliecer Coto García, Carmen Díaz Corte y Carlos López LarreapeerReviewe
Improvement and sustainable management of river corridors in the Iberian Atlantic Region
Resumen de la contribución presentada en el congreso.SER Europe Conference, Restoration in the Era of Climate Change (11th, 2018, Reykjavick)Se incluyen 2 archivos: resumen de la ponencia y póster de la misma.VERBATIM: In the Iberian Atlantic Region, there are several landscape change processes (changes in the land use, presence of invasive species, activities regarding public use, intensification of agricultural and livestock farming, climate change) and phytosanitary problems (alder diseases caused by Phytophthora ssp.) that, currently, are threat factors of river corridor habitats. These factors are deteriorating and fragmenting them, and having a relevant impact on their functionality. The LIFE Fluvial project aims to mitigate these consequences, to improve the conservation status and to develop sustainable management measures of river and fluvio-estuarine corridors. Selected areas in the project are Natura 2000 sites belonging to several river basins located in the northwest of the Iberian Peninsula (Spain and Portugal). To this aim, LIFE Fluvial has designed the following actions: A detailed analysis of the current status and implementation of a trans-national model for the sustainable management of river corridors to reduce the negative impact caused by the threats and to avoid their spread towards other UE territories. Design and implementation of restoration projects to improve conservation status of the natural habitats of interest, connectivity and to reduce fragmentation. Control of invasive flora species that pose a threat to the conservation of river corridors, and improvement of their phytosanitary state by removing trees infected by Phytophthora Dissemination of the environmental relevance of river corridors and social awareness in terms of socioeconomic benefits and ecosystem services provided. Improvement of training/education and technical empowerment of the stakeholders involved in the management and conservation of river corridors. The project lasts four years (2017-2021) and includes a system to monitor the impact of the actions on habitats and ecosystem services provided by river corridors
Resistance to Bleomycin-Induced Lung Fibrosis in MMP-8 Deficient Mice Is Mediated by Interleukin-10
BACKGROUND: Matrix metalloproteinases (MMPs) may have pro and antifibrotic roles within the lungs, due to its ability to modulate collagen turnover and immune mediators. MMP-8 is a collagenase that also cleaves a number of cytokines and chemokines. METHODOLOGY AND PRINCIPAL FINDINGS: To evaluate its relevance in lung fibrosis, wildtype and Mmp8(-/-) mice were treated with either intratracheal bleomycin or saline, and lungs were harvested at different time points. Fibrosis, collagen, collagenases, gelatinases, TGFβ and IL-10 were measured in lung tissue. Mmp8(-/-) mice developed less fibrosis than their wildtype counterparts. This was related to an increase in lung inflammatory cells, MMP-9 and IL-10 levels in these mutant animals. In vitro experiments showed that MMP-8 cleaves murine and human IL-10, and tissue from knockout animals showed decreased IL-10 processing. Additionally, lung fibroblasts from these mice were cultured in the presence of bleomycin and collagen, IL-10 and STAT3 activation (downstream signal in response to IL-10) measured by western blotting. In cell cultures, bleomycin increased collagen synthesis only in wildtype mice. Fibroblasts from knockout mice did not show increased collagen synthesis, but increased levels of unprocessed IL-10 and STAT3 phosphorylation. Blockade of IL-10 reverted this phenotype, increasing collagen in cultures. CONCLUSIONS: According to these results, we conclude that the absence of MMP-8 has an antifibrotic effect by increasing IL-10 and propose that this metalloprotease could be a relevant modulator of IL-10 metabolism in vivo
COVID-19 Associated Pulmonary Aspergillosis (CAPA): Hospital or Home Environment as a Source of Life-Threatening Aspergillus fumigatus Infection?
Most cases of invasive aspergillosis are caused by Aspergillus fumigatus, whose conidia are ubiquitous in the environment. Additionally, in indoor environments, such as houses or hospitals, conidia are frequently detected too. Hospital-acquired aspergillosis is usually associated with airborne fungal contamination of the hospital air, especially after building construction events. A. fumigatus strain typing can fulfill many needs both in clinical settings and otherwise. The high incidence of aspergillosis in COVID patients from our hospital, made us wonder if they were hospital-acquired aspergillosis. The purpose of this study was to evaluate whether the hospital environment was the source of aspergillosis infection in CAPA patients, admitted to the Hospital Universitario Central de Asturias, during the first and second wave of the COVID-19 pandemic, or whether it was community-acquired aspergillosis before admission. During 2020, sixty-nine A. fumigatus strains were collected for this study: 59 were clinical isolates from 28 COVID-19 patients, and 10 strains were environmentally isolated from seven hospital rooms and intensive care units. A diagnosis of pulmonary aspergillosis was based on the ECCM/ISHAM criteria. Strains were genotyped by PCR amplification and sequencing of a panel of four hypervariable tandem repeats within exons of surface protein coding genes (TRESPERG). A total of seven genotypes among the 10 environmental strains and 28 genotypes among the 59 clinical strains were identified. Genotyping revealed that only one environmental A. fumigatus from UCI 5 (box 54) isolated in October (30 October 2020) and one A. fumigatus isolated from a COVID-19 patient admitted in Pneumology (Room 532-B) in November (24 November 2020) had the same genotype, but there was a significant difference in time and location. There was also no relationship in time and location between similar A. fumigatus genotypes of patients. The global A. fumigatus, environmental and clinical isolates, showed a wide diversity of genotypes. To our knowledge, this is the first study monitoring and genotyping A. fumigatus isolates obtained from hospital air and COVID-19 patients, admitted with aspergillosis, during one year. Our work shows that patients do not acquire A. fumigatus in the hospital. This proves that COVID-associated aspergillosis in our hospital is not a nosocomial infection, but supports the hypothesis of "community aspergillosis" acquisition outside the hospital, having the home environment (pandemic period at home) as the main suspected focus of infection.S
MOOC Español Salamanca A2
Memoria ID-0007. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015
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