127 research outputs found

    Network-constrained models of liberalized electricity markets: the devil is in the details

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    Numerical models for electricity markets are frequently used to inform and support decisions. How robust are the results? Three research groups used the same, realistic data set for generators, demand and transmission network as input for their numerical models. The results coincide when predicting competitive market results. In the strategic case in which large generators can exercise market power, the predicted prices differed significantly. The results are highly sensitive to assumptions about market design, timing of the market and assumptions about constraints on the rationality of generators. Given the same assumptions the results coincide. We provide a checklist for users to understand the implications of different modelling assumptions.Market power, Electricity, Networks, Numeric models, Model comparison

    Influência do estado emocional no desempenho: Estudo experimental

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    Objetivo: El presente estudio pretende conocer la influencia que ejerce el estado emocional y la manipulación afectiva en el rendimiento deportivo, de forma experimental. Método: 126 deportistas universitarios (Medad = 22.79; DT = 4.46), 54 mujeres (42.86%) y 7.78 años de experiencia deportiva (DT = 3.20), participaron en este estudio que midió el optimismo (LOT-R) y el estado emocional (POMS-VIC) antes y después de realizar un test experimental mediante dinamómetro manual digital TKK-5401. Resultados: Al considerar los diferentes grupos (género, experiencia, nivel, optimismo y grupo experimental), destaca la no aparición de diferencias significativas (pre-post). Conclusiones: Los resultados demuestran que tanto estado emocional como las manipulaciones afectivas modifican el rendimiento. En concreto, las manipulaciones afectivas, ligeramente negativas, aumentan significativamente el rendimiento obtenido en la tareaObjective: The aim of this study is to experimentally determine the influence of the emotional state and the emotional manipulation in sports performance. Method: 126 college athletes (Mage = 22.79; DT = 4.46), 54 women (42.86%) y 7.78 year of sports experience (DT = 3.20), participated in this study, which measured optimism (LOT-R) and emotional state (POMS-VIC) before and after performing an experimental test using digital manual dynamometer TKK- 5401. Results: Considering the different groups (gender, experience, level, optimism and experimental group), it emphasizes the non-appearance of significant differences (pre-post). Conclusions: Results have shown both the emotional state and the effective manipulations modify the performance slightly negative emotional manipulations significantly increase the yield obtained in the taskObjetivo: O presente estudo tem como objetivo conhecer a influência exercida pelo estado emocional e manipulação afetiva no desempenho esportivo, de forma experimental. Método: 126 atletas universitários (idade = 22.79, DP = 4.46), 54 mulheres (42.86%) e 7.78 anos de experiência esportiva (DP = 3.20), participaram deste estudo que mediu otimismo (LOT-R) e estado emocional (POMS-VIC) antes e depois de realizar um teste experimental usando um dinamômetro digital manual TKK-5401. Resultados: Ao considerar os diferentes grupos (gênero, experiência, nível, otimismo e grupo experimental), destaca-se o não aparecimento de diferenças significativas (pré-pós). Conclusões: Os resultados mostram que tanto o estado emocional quanto as manipulações afetivas modificam o desempenho. Em particular, as manipulações afetivas, levemente negativas, aumentam significativamente o desempenho obtido na taref

    Concentración sanguínea de aluminio en pacientes adultos: efecto de la nutrición parenteral tricameral frente a la nutrición parenteral elaborada en el hospital

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    Nutrició parenteral; Alumini; ToxicitatParenteral nutrition; Aluminum; ToxicityNutrición parenteral; Aluminio; ToxicidadBackground: the administration of aluminum-contaminated parenteral nutrition (PN) leads to an accumulation of aluminum. The aim of this study was to assess blood aluminum concentrations (BACs) of inpatients receiving multichamber-bag (MCB) PN compared to those receiving compounded PN. Methods: available BACs were retrospectively gathered from patient charts of adult inpatients receiving PN from 2015 to 2020, and compared depending on the type of PN administered. Long-term PN patients, defined as ≥ 20 days of PN, receiving at least > 10 days of compounded PN, were compared to long-term patients receiving only MCB. Results: a total of 160 BACs were available from 110 patients. No differences were found according to type of PN (mean BAC: 3.11 ± 2.75 for MCB versus 3.58 ± 2.08 µg/L for compounded PN). Baseline total bilirubin, surgery and days with PN were related to higher BACs (coefficient: 0.30 [95 % CI, 0.18-0.42], 1.29 [95 % CI, 0.52-2.07], and 0.06 [95 % CI: 0.01-0.11], respectively). Regarding long-term PN, patients receiving only MCB (n = 21) showed lower BACs compared to the compounded PN (n = 17) [2.99 ± 1.55 versus 4.35 ± 2.17 µg/L, respectively; p < 0.05]. Conclusions: although there were no differences in BAC according to type of PN administered, in long-term PN, MCB PN was associated with lower BACs as compared to compounded PN.Antecedentes: la administración de nutrición parenteral (NP) contaminada con aluminio conduce a su acumulación. El objetivo de este estudio fue evaluar las concentraciones de aluminio en sangre (CAS) en pacientes hospitalizados que recibieron NP elaboradas en el hospital o bolsas tricamerales. Métodos: se recogieron retrospectivamente las CAS disponibles de los pacientes hospitalizados con NP durante el período entre 2015 y 2020, comparándose los valores en función del tipo de NP administrada. Se comparan igualmente los valores de pacientes de larga duración, definida como ≥ 20 días de NP, que recibieron al menos > 10 días de NP elaborada frente aquellos de larga duración que recibieron solo NP tricameral. Resultados: se incluyeron un total de 160 CAS de 110 pacientes. No se encontraron diferencias con respecto al tipo de NP (CAS media: 3,11 ± 2,75 para la tricameral frente a 3,58 ± 2,08 µg/L para la elaborada). La bilirrubina total basal, la cirugía y los días con NP se relacionaron con un mayor valor de CAS (coeficiente: 0,30 [IC 95 %: 0,18-0,42], 1,29 [IC 95 %: 0,52-2,07] y 0,06 [IC 95 %: 0,01-0,11], respectivamente). En la NP a largo plazo, los pacientes que recibieron solo NP tricameral (n = 21) mostraron una CAS menor en comparación con el grupo que recibió al menos 10 NP elaboradas (n = 17) [2,99 ± 1,55 versus 4,35 ± 2,17 µg/L, respectivamente; p < 0,05]. Conclusiones: aunque no hubo diferencias de CAS con respecto al tipo de NP administrada, en la NP a largo plazo, la administración de NP tricameral se asoció con CAS menores en comparación con la NP elaborada

    Using Food Webs and Metabolic Theory to Monitor, Model, and Manage Atlantic Salmon-A Keystone Species Under Threat

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    Populations of Atlantic salmon are crashing across most of its natural range: understanding the underlying causes and predicting these collapses in time to intervene effectively are urgent ecological and socioeconomic priorities. Current management techniques rely on phenomenological analyses of demographic population time-series and thus lack a mechanistic understanding of how and why populations may be declining. New multidisciplinary approaches are thus needed to capitalize on the long-term, large-scale population data that are currently scattered across various repositories in multiple countries, as well as marshaling additional data to understand the constraints on the life cycle and how salmon operate within the wider food web. Here, we explore how we might combine data and theory to develop the mechanistic models that we need to predict and manage responses to future change. Although we focus on Atlantic salmon-given the huge data resources that already exist for this species-the general principles developed here could be applied and extended to many other species and ecosystems

    1-Ethyl-2,3-dimethylimidazolium paramagnetic ionic liquids with 3D magnetic ordering in its solid state: synthesis, structure and magneto-structural correlations

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    Financial support from the Spanish Ministerio de Ciencia e Innovaci´on (Projects MAT2011-27573-C04) and Becas Iberoamericas J´ovenes Profesores Investigadores, 2015, Santander Universidades is acknowledged. The authors gratefully acknowledge the MALTA Consolider Ingenio 2010 (Ref. CSD2007-00045). IH acknowledges funding from the EU FP7 (Marie Curie-CIG 303535)

    Nanoflowers Versus Magnetosomes Comparison Between Two Promising Candidates for Magnetic Hyperthermia Therapy

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    Magnetic Fluid Hyperthermia mediated by iron oxide nanoparticles is one of the most promising therapies for cancer treatment. Among the different candidates, magnetite and maghemite nanoparticles have revealed to be some of the most promising candidates due to both their performance and their biocompatibility. Nonetheless, up to date, the literature comparing the heating efficiency of magnetite and maghemite nanoparticles of similar size is scarce. To fill this gap, here we provide a comparison between commercial Synomag Nanoflowers pure maghemite and bacterial magnetosomes pure magnetite synthesized by the magnetotactic bacterium Magnetospirillum gryphiswaldense of amp; 10216;D amp; 10217; amp; 8776; 40 45 nm. Both types of nanoparticles exhibit a high degree of crystallinity and an excellent degree of chemical purity and stability. The structural and magnetic properties in both nanoparticle ensembles have been studied by means of X Ray Diffraction, Transmission Electron Microscopy, X Ray Absorption Spectroscopy, and SQUID magnetometry. The heating efficiency has been analyzed in both systems using AC magnetometry at several field amplitudes 0 88 mT and frequencies 130, 300, and 530 kH

    A practical perspective on the potential of rechargeable Mg batteries

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    Emerging energy storage systems based on abundant and cost-effective materials are key to overcome the global energy and climate crisis of the 21st century. Rechargeable Magnesium Batteries (RMB), based on Earth-abundant magnesium, can provide a cheap and environmentally responsible alternative to the benchmark Li-ion technology, especially for large energy storage applications. Currently, RMB technology is the subject of intense research efforts at laboratory scale. However, these emerging approaches must be placed in a real-world perspective to ensure that they satisfy key technological requirements. In an attempt to bridge the gap between laboratory advancements and industrial development demands, herein, we report the first non-aqueous multilayer RMB pouch cell prototypes and propose a roadmap for a new advanced RMB chemistry. Through this work, we aim to show the great unrealized potential of RMBs.This work was funded by European Union's Horizon 2020 research and innovation program under the FET Proactive call with grant agreement no 824066 via the “E-MAGIC” project

    Mapping the temporary and perennial character of whole river networks

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    Knowledge of the spatial distribution of temporary and perennial river channels in a whole catchment is important for effective integrated basin management and river biodiversity conservation. However, this information is usually not available or is incomplete. In this study, we present a statistically based methodology to classify river segments from a whole river network (Deva-Cares catchment, Northern Spain) as temporary or perennial. This method is based on an a priori classification of a subset of river segments as temporary or perennial, using field surveys and aerial images, and then running Random Forest models to predict classification membership for the rest of the river network. The independent variables and the river network were derived following a computer-based geospatial simulation of riverine landscapes. The model results show high values of overall accuracy, sensitivity, and specificity for the evaluation of the fitted model to the training and testing data set (?0.9). The most important independent variables were catchment area, area occupied by broadleaf forest, minimum monthly precipitation in August, and average catchment elevation. The final map shows 7525 temporary river segments (1012.5 km) and 3731 perennial river segments (662.5 km). A subsequent validation of the mapping results using River Habitat Survey data and expert knowledge supported the validity of the proposed maps. We conclude that the proposed methodology is a valid method for mapping the limits of flow permanence that could substantially increase our understanding of the spatial links between terrestrial and aquatic interfaces, improving the research, management, and conservation of river biodiversity and functioning.We would like to thank the Journal Editor and the three referees for their comments and suggestions, which have greatly improved the manuscript. This study was partly funded by the Spanish Ministry of Economy and Competitiveness as part of the RIVERLANDS (Ref: BIA-2012–33572) and HYDRA (Ref: BIA-2015–71197) projects. Alexia María González-Ferreras is supported by a predoctoral research grant (Ref: BES-2013–065770) from the Spanish Ministry of Economy and Competitiveness, and José Barquín was supported by a Ramon y Cajal grant (Ref: RYC-2011–08313) from the Spanish Ministry of Economy and Competitiveness. We would like to thank the Government of Cantabria, the Principado de Asturias and the forest guards of the study areas for providing useful information. We would also like to acknowledge the Interautonomic Consortium of the Picos de Europa National Park and the Biodiversity Foundation from the Ministry of Agriculture, Food and Environment, for their advice and project support. Finally, we would also like to thank all the people involved in the field data collection, and those who read an early draft of the manuscript and suggested several improvements. The data and the data sources used in this study are cited and explained in the text. Readers can obtain further information about the data supporting the analysis and conclusions by contacting the corresponding author
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