99 research outputs found

    Systematic calibration of N2O emissions from a full-scale WWTP including a tracer test and a global sensitivity approach

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    Altres ajuts: Acord transformatiu CRUE-CSICBorja Solís is grateful for the PIF PhD grant funded by Universitat Autònoma de Barcelona.Nitrous oxide (NO) is a greenhouse gas (GHG) emitted during biological nitrogen removal from wastewater treatment plants (WWTPs). Some modelling tools have been proposed to predict NO emissions during the design and operation of WWTPs. In this study, the novel ASM2d-NO model, which accounts for the production of NO in nutrient removal WWTPs, was used to study the associated emissions from a full-scale WWTP with two independent lines. Firstly, the hydraulics of the WWTP was characterized by a residence time distribution test, showing the flow was equally divided into the two treatment lines (49.3 vs. 50.7%), that each reactor worked as an ideal continuous stirred tank reactor and the secondary settler model flux was similar to a plug-flow reactor. The ASM2d-NO model was then calibrated using experimental data obtained under dynamic conditions. A global sensitivity analysis was used to select, among 59 model parameters, five candidates that resulted to be related to nitrifying organisms. Different parameter subsets up to four parameters were evaluated, being the subset [µ, q, K, K] the best, achieving 53.3% reduction of the calibration cost function. The model fit obtained provided a reasonably description of nutrients and NO emission trends, considering the inherent operational variability suffered in full-scale WWTPs. Finally, a simulation-based study showed that, for the given WWTP and operational conditions, an unbalanced distribution of flow-rate between the two treatment lines did not result in a significant increase on NO emissions. The results obtained show that this model can be a suitable tool for predicting NO emissions in full-scale WWTPs, and can therefore be used to find operational conditions that help to minimise these emissions

    Direct and indirect effects of climate on demography and early growth of Pinus sylvestris at the rear edge: changing roles of biotic and abiotic factors

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    Global change triggers shifts in forest composition, with warming and aridification being particularly threatening for the populations located at the rear edge of the species distributions. This is the case of Scots pine (Pinus sylvestris) in the Mediterranean Basin where uncertainties in relation to its dynamics under these changing scenarios are still high. We analysed the relative effect of climate on the recruitment patterns of Scots pine and its interactions with local biotic and abiotic variables at different spatial scales. Number of seedlings and saplings was surveyed, and their annual shoot growth measured in 96 plots located across altitudinal gradients in three different regions in the Iberian Peninsula. We found a significant influence of climate on demography and performance of recruits, with a non-linear effect of temperature on the presence of juveniles, and a positive effect of precipitation on their survival. Abundance of juveniles of P. sylvestris that underwent their first summer drought was skewed towards higher altitudes than the altitudinal mean range of the conspecific adults and the optimum elevation for seedlings¿ emergence. At local level, light availability did not influence juveniles¿ density, but it enhanced their growth. Biotic interactions were found between juveniles and the herb cover (competition) and between the number of newly emerged seedlings and shrubs (facilitation). Results also highlighted the indirect effect that climate exerts over the local factors, modulating the interactions with the pre-existing vegetation that were more evident at more stressful sites. This multiscale approach improves our understanding of the dynamics of these marginal populations and some management criteria can be inferred to boost their conservation under the current global warming.Funding was provided by the Spanish Ministry for Innovation and Science with the grant Consolider-Montes (CSD2008_00040), and the European Union with the projects BACCARA (CE: FP7-226299, 7FP) and FunDivEUROPE (CE: FP7-ENV-2010. 265171).Peer Reviewe

    Added value of intraoperative real-time imaging in searches for difficult-to-locate sentinel nodes.

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    Localization of sentinel lymph nodes can be challenging if they are in difficult anatomic locations or near high radiotracer activity The purpose of this study was to assess the value of intraoperative real-time imaging using a portable gamma-camera in conjunction with a conventional gamma-counting probe when it is difficult to localize the sentinel node

    Demografía y crecimiento primario durante la regeneración de tres especies de pino a lo largo de gradientes climáticos

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    13 páginas, 4 figuras y 3 tablasLa regeneración es un proceso crítico en la dinámica de los bosques, que presenta una marcada heterogeneidad temporal y espacial. En este trabajo se pretende avanzar en el conocimiento de las variables bióticas y abióticas que determinan a escala local la presencia, abundancia y crecimiento primario de plántulas de tres especies de pino: Pinus sylvestris, P. nigra y P. uncinata, y determinar el efecto relativo del clima. Para ello se muestrearon 216 parcelas distribuidas a lo largo de gradientes climáticos en siete localidades montañosas. Se censaron las plántulas recién emergidas y el resto de juveniles, y se midieron los crecimientos anuales. Los resultados mostraron diferencias significativas entre especies con efectos directos e indirectos del clima sobre la demografía y el estado de los juveniles. En las tres especies se apreció que la supervivencia de los juveniles aparecía desplazada hacia altitudes mayores respecto donde se producía el óptimo de la emergencia. Las relaciones locales de competencia y facilitación ejercieron efectos importantes sobre la regeneración de las tres especies, siendo éstos modulados por el clima.Ministerio Español de Innovación y Ciencia Consolider-Montes (CSD2008_00040), Los autores agradecen a toda la gente que hizo posible el trabajo de campo: R. Freire, B. Santamaría, J. Martínez, D. López, R. Ruíz-Puche, E. Molina, L. Ivorra, S. Martín, B. Ros y C. Boubekeur. También el apoyo estadístico de R. Manson.Proyecto europeo BACCARA (CE: FP7-226299, 7FP)Peer reviewe

    Seroprevalence of anti-SARS-CoV-2 antibodies in household domestic ferrets (Mustela putorius furo) in Spain, 2019–2023

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    SARS-CoV-2 is the causal agent of Coronavirus Disease 2019 (COVID-19) in humans that emerged in late 2019. This virus is able to infect humans and different animal species. Among pets, cats and ferrets are more susceptible to be infected by the SARS-CoV-2. Epidemiological studies are an important tool to provide information under natural conditions of exposure to SARS-CoV-2 virus. In comparison to cats, limited epidemiological studies have been performed in domestic ferrets (Mustela putorius furo) reporting the presence of antibodies in this species. This study analysed the presence of anti-SARS-CoV-2 antibodies in 432 cliend-owned ferrets from different geographical areas of Spain during the different waves of COVID-19 outbreaks from December 2019 to May 2023 (42 months). For this purpose, anti-SARS-CoV-2 antibodies were detected by an enzyme-linked immunosorbent method (ELISA) using the receptor binding domain (RBD) of Spike antigen and confirmed by serum virus neutralization assay. Eighteen of the 432 ferrets included were seroreactive by the in-house ELISA (4.17%, 95% Confidence Interval (CI): 2.65–6.49). In this sense, the wave of COVID-19 with the higher number of seropositive ferrets occurred during the seventh wave when the different Omicron subvariants were the dominant virus variants. Our results suggest that the risk of SARS-CoV-2 transmission in domestic ferrets in natural conditions is low. Further research is need to evaluate the potential risk of transmission of SARS-CoV-2 from human to pets

    Eina per a la captació de talent al grau d'enginyeria química (#TEQxC2): el cas de la UPC Manresa

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    L'ocupabilitat és un dels atractius que aporten valor als estudis de grau de les enginyeries. En aquest sentit la UPC de Manresa dinamitza la captació d'estudiants en el grau d'enginyeria química a partir del programa talent en l'enginyeria química per a la Catalunya central, en el qual s'ofereix com a ingredient singular l'experiència d'enginyers que treballen en la indústria com a vincle per captar l'interès dels estudiants de batxillerat a partir de la selecció dels professors de batxillerat. Employability is one of the attractions that add value to undergraduate engineering degree studies. In this sense, the UPC of Manresa dynamizes the recruitment of students in the degree of chemical engineering from the talent program in chemical engineering for Central Catalonia, (TECxC2) which offers as an outstanding ingredient the experience of engineers who work in industry as a link to attract the interest of high school students from the selection made by their own teachers.Peer ReviewedPostprint (published version

    Despertar la curiosidad por la química desde la Universidad

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    En este trabajo se presentará la experiencia realizada a partir de la visita a la exposición “¿Dónde está la química?”, por parte de estudiantes de secundaria, ciclos formativos y bachillerato. Esta exposición se ha programado desde la Escola Universitària Politècnica de Manresa de la Universitat Politècnica de Catalunya, con el objetivo de acercar a los estudiantes de este nivel al conocimiento y, más que nada, a la curiosidad por el mundo de la química. Se expondrá en primer lugar el material que se presenta en la exposición, así como los resultados obtenidos en una encuesta realizada a los asistentes una vez concluida la visita, y en segundo lugar se presentarán las conclusiones obtenidas de la valoración indicada.Peer ReviewedPostprint (published version

    Effect of time to sentinel-node biopsy on the prognosis of cutaneous melanoma

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    Introduction: In patients with primary cutaneous melanoma, there is generally a delay between excisional biopsy of the primary tumour and sentinel-node biopsy. The objective of this study is to analyse the prognostic implications of this delay. Patients and method: This was an observational, retrospective, cohort study in four tertiary referral hospitals. A total of 1963 patients were included. The factor of interest was the interval between the date of the excisional biopsy of the primary melanoma and the date of the sentinel-node biopsy (delay time) in the prognosis. The primary outcome was melanoma-specific survival and disease-free survival. Results: A delay time of 40 days or less (hazard ratio (HR), 1.7; confidence interval (CI), 1.2-2.5) increased Breslow thickness (Breslow ⩾2 mm, HR, >3.7; CI, 1.4-10.7), ulceration (HR, 1.6; CI, 1.1-2.3), sentinel-node metastasis (HR, 2.9; CI, 1.9-4.2), and primary melanoma localised in the head or neck were independently associated with worse melanoma-specific survival (all P < 0.03). The stratified analysis showed that the effect of delay time was at the expense of the patients with a negative sentinel-node biopsy and without regression. Conclusion: Early sentinel-node biopsy is associated with worse survival in patients with cutaneous melanoma
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