2,961 research outputs found
The daily price and income elasticity of natural gas demand in Europe
Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Data from 15 European countries is analysed to provide novel estimates of daily own-price, cross-price and income elasticities of natural-gas-demand from 2016 to 2020. The results show that: first, there is a strong-seasonal component in the October–February period during which residential-demand has a higher share on total demand, and gas price is not a determinant factor for most of the countries. This seasonal profile makes price-based tools more effective modifying end-consumer behaviours from March to August when estimated own-price elasticities present larger values in absolute terms. Second, there are estimated positive own-price elasticities from October to February in Bulgaria, Luxemburg, Poland, the UK, and Portugal. The first four countries present natural gas prices below the EU-28 average during the analysed period and it is argued that positive elasticities may reflect a disconnection between the price traded on the organized markets and the real price perceived by end-customers. For Portugal, who is currently carrying out a very aggressive policy to become coal-free by the end of 2021, natural gas and coal are mainly consumed in power sector to provide flexibility and back up renewable generation. The limited alternatives to provide these services may explain why coal and natural gas are found to be complementary. Finally, it is found that lockdowns due to covid-19 highly impacted on natural gas demand, confirming for the first time in the literature a “double heating effect”. Our results help to find when price-based tools by policymakers will influence more effectively natural-gas-demand following economic and environmental goals.Ministerio de Ciencia e Innovación ; PGC2018-101327-B-100Xunta de Galicia ; ED431C 2020/2
Interannual analysis of the biological parameters of Trachurus mediterraneus (Steindachner 1868) in the Spanish Mediterranean Sea
Recreational water skiing in people with paraplegia: A study of three cases
Objetivos: se analizaron la condición cardiorrespiratoria y la intensidad de esfuerzo durante la práctica recreativa del esquí náutico de slalom. Metodología: participaron tres esquiadores náuticos con paraplejia moderadamente activos. Realizaron un test incremental en un ergómetro de brazos para determinar su VO2pico y los umbrales ventilatorios y completaron 3 sesiones de práctica de esquí náutico, separadas por 48h, registrándose la FC cada 5 s. Resultados: obtuvieron un VO2pico de 22,3 ± 0,6 mL·kg-1·min-1 y los umbrales ventilatorios se analizaron al ~80 y ~50% del VO2pico. La FC media en las sesiones de esquí náutico fue de 111 ppm, lo que representó una intensidad de ~45% de la FC de reserva (FCR), permaneciendo por encima del 40% de la FCR ~12 min. Conclusión: la intensidad moderada de la práctica recreativa de esquí náutico de slalom podría servir para mantener o mejorar la condición cardiorrespiratoria en estas tres personas con paraplejiaObjectives: the cardiorespiratory fitness and the intensity of effort were analyzed during the recreational practice of slalom water skiing. Methodology: three moderately active water skiers with paraplegia participated. They performed an incremental test on an arm ergometer to determine their VO2peak and ventilatory thresholds and completed 3 sessions of water skiing, separated by 48h, where the HR was recorded every 5 s. Results: they obtained a VO2peak of 22.3 ± 0.6 mL·kg-1·min-1 and the ventilatory thresholds were analyzed at ~80 and ~50% of the VO2peak. The average heart rate in the water ski sessions was 111 bpm, which represented an intensity of ~45% of the heart rate reserve (HRR), remaining above 40% of the HRR ~12 min. Conclusion: the moderate intensity of recreational slalom skiing could serve to maintain or improve the cardiorespiratory fitness in these three people with paraplegi
Bub1 as a recruitment platform for Spindle Assembly Checkpoint components
Motivation: The Spindle Assembly Checkpoint (SAC) is a safeguard mechanism conserved in all the eukaryotes that ensures the correct chromosome segregation in mitosis by preventing the premature mitotic exit in condition of unattached kinetochores. SAC defects lead to chromosome mis-segregation provoking aneuploidies that has been widely associated with cancer. Kinase Bub1 is a key player in SAC function because it maintains a proper centromeric cohesion and serves as a platform for other SAC components such as Mad1, Mad2 and Mad3. In this study, we are characterizing a bub1 mutant allele which exhibits an impaired SAC function. The phenotype shown by this mutant has not been previously described. This mutant can provide new insights about the Bub1-dependent recruitment of SAC components to the kinetochores and the mechanism of mitosis arrest.Methods: We made use of live imaging techniques to study SAC function by using GFP-tagged alleles of the main SAC components (like Mad1, Mad2 and Mad3), comparing the wild type background versus the bub1 mutant allele. Furthermore, we have used a cold sensitive tubulin mutant that allows us to test SAC activity; in response to microtubules damage induced by this mutant, cells activate the SAC and arrest in metaphase. We have also tested Bub1 protein levels in a wild-type and in the Bub1-mutant by Western Blot. Finally, we are performing a two-hybrid screening using a S. pombe library-strain to detect differences in the interactome of the Bub1-mutant compared with the wild-type. Results: We have demonstrated that in the Bub1-mutant background, Mad1 correctly localizes at the kinetochores meanwhile Mad2 does not. Bub1 protein levels turned out to be quite similar in both strain. Additionally, we have observed that the SAC defects notice in the Bub1-mutant in the cold sensitive background partially phenocopies the one seen in the Bub1-deleted cells.Conclusions: Our Bub1-mutant is unable to maintain a proper metaphase block in the cold-sensitive tubulin background and exhibit a SAC failure. We are working in a model where Bub1 could be regulating SAC activity by promoting Mad2 recruitment to kinetochores
Correlation between Spectroscopic and Mechanical Properties of Gold Nanocrystals under Pressure
The effects of nonhydrostatic pressure on the morphology and stability of gold nanorods (AuNRs) and nanospheres (AuNSs) in 4:1 methanol-ethanol mixtures were studied by optical absorption spectroscopy and transmission electron microscopy at pressures of up to 23 and 30 GPa, respectively. Solvent solidification and associated nonhydrostatic stresses were found to have a negligible effect on the shape and size of AuNSs. On the contrary, while AuNRs maintained their initial morphology in the hydrostatic range, the uniaxial stress component induced under nonhydrostatic conditions had a shearing effect on the AuNRs, breaking them into smaller particles. Interestingly, colloidal stability was maintained in all cases, and the particles showed no sign of aggregation, despite the severe nonhydrostatic conditions to which both AuNR and AuNS colloids were subjected.Financial support from Projects PGC2018-101464−B-I00 (Ministerio de Ciencia, Innovación y Universidades) and MALTA-Consolider Team (RED2018-102612-T) is acknowledged. We acknowledge J. A. Barreda-Argüeso and J. RuizFuertes for support with high-pressure measurements. P.M. thanks the ARC for grant CE170100026. L.M.L.-M. acknowledges grant PID2020-117779R and the Maria de Maeztu Units of Excellence Program (grant MDM-2017-0720) from the Spanish Ministerio de Ciencia e Innovación
Switching Costs in the European Postal Service. Are There Any Solutions?
[Abstract] This article examines the costs of switching that may exist in the European postal sector, where it is carried out an ambitious process of opening to competition since 1997. Inadequate regulation of the access to some elements of postal infrastructure or services within the scope of the universal postal service exists. This article proposes adaptations to ensure transparent and non-discriminatory access conditions to elements of postal infrastructure in line with the sectorial directives aimed at strengthening competition in the long term in the postal market. The proposed adaptations focus on services such as postcode systems, address databases, post office boxes, delivery boxes, re-direction and return to sender services. All of them can help reduce the switching cost and thus strengthen competition
Towards a fuzzy-based multi-classifier selection module for activity recognition applications
Performing activity recognition using the information provided by the different sensors embedded in a smartphone face limitations due to the capabilities of those devices when the computations are carried out in the terminal. In this work a fuzzy inference module is implemented in order to decide which classifier is the most appropriate to be used at a specific moment regarding the application requirements and the device context characterized by its battery level, available memory and CPU load. The set of classifiers that is considered is composed of Decision Tables and Trees that have been trained using different number of sensors and features. In addition, some classifiers perform activity recognition regardless of the on-body device position and others rely on the previous recognition of that position to use a classifier that is trained with measurements gathered with the mobile placed on that specific position. The modules implemented show that an evaluation of the classifiers allows sorting them so the fuzzy inference module can choose periodically the one that best suits the device context and application requirements
Synthesis and Electrocatalytic Properties of H2SO4-Induced (100) Pt Nanoparticles Prepared in Water-in-Oil Microemulsion
The increasing number of applications for shape-controlled metal nanoparticles (NPs) has led to the need for easy, cheap, and scalable methodologies. We report the synthesis of (100) preferentially oriented Pt NPs, with a particle size of 9 nm, by using a water-in-oil microemulsion method. The specific surface structure of the NPs is induced by the presence of H2SO4 in the water phase of the microemulsion. Interestingly, the results reported herein show how increasing amounts of H2SO4 lead to the formation of Pt NPs containing a larger amount of (100) sites on their surface. This preferential surface orientation is confirmed electrochemically by using the so-called hydrogen adsorption/desorption process. In addition, transmission electron microscopy measurements confirm the presence of cubic-like Pt NPs. Finally, the electrocatalytic properties of the Pt NPs are evaluated towards ammonia and CO electro-oxidations, which are (100) structure-sensitive reactions.This work has been financially supported by the MCINN-FEDER (Spain) (project CTQ 2010-16271), Generalitat Valenciana (project PROMETEO/2009/045) and in part by NASA-URC Grant No. NNX10AQ17A and NSF-NSEC Center for Hierarchical Manufactur-ing Grant No. CHM-CMMI-0531171. R. M-R is grateful to the Becas Iberoamérica, Santander Universidades-España 2012 and PR-LSAMP Bridge to Doctorate Fellowship programs
Ventilatory threshold prediction by spectral analysis of heart rate variability in incremental maximal tests
Ventilatory thresholds (VT1 and VT2) are useful in
many fields of medicine and sports. Nevertheless, their
measurement is cumbersome and needs trained
personnel. This work proposes an alternative method to
predict VT1, VT2 and maximum loads in incremental
maximal tests based on heart rate variability (HRV)
analysis. Twelve competitive male cyclists executed an
incremental exhaustive test. During the test, RR time
series and gas concentrations were recorded. After
artifact correction the power spectrum was estimated in a
sliding window, and central frequency (CF) and
bandwidth that contains half the total power (BW) were
computed. An automatic algorithm recognized the loads
where CF and BW undergo a significant change. These
loads were used as inputs in linear regression models to
predict VT1, VT2 and maximum loads. The errors of the
predictions are similar to the load resolution.Postprint (published version
Papel de los equipos de atención primaria en la hospitalización infantil de los niños menores de 2 años
ObjetivoDeterminar si la conformación de los equipos de atención primaria con la realización del programa de salud del niño sano da lugar a una disminución del riesgo de hospitalización en los niños menores de 2 años, respecto al sistema sanitario tradicional de consultorio o ambulatorio.DiseñoEstudio epidemiológico de casos-referencia.Casos40% de los niños hospitalizados menores de 24 meses en plantas de hospitalización pediátricas o neonatal del Hospital Universitario Marqués de Valdecilla.Referencia15% de los recién nacidos vivos en dicho hospital. Recogida de información mediante entrevista personal y consulta de la tarjeta sanitaria.Período de estudioabril de 1995 a mayo de 1996.ResultadosLos niños menores de 2 años controlados habitualmente por un médico perteneciente a un equipo de atención primaria presentan una disminución del riesgo de hospitalización para todos los diagnósticos clínicos de 0,57 (IC del 95%, 0,35–0,93), tras haber ajustado por diferentes factores de confusión como educación materna, clase social, etnia, edad materna, consumo de tabaco materno, lactancia natural al nacimiento, ingreso al nacimiento. Se observó una disminución del riesgo de hospitalización por fiebre sin localización aparente en aquellos niños controlados habitualmente por un médico de equipo (RR ajustado, 0,41; IC del 95%, 0,19–0,90).ConclusiónLas ventajas de la reforma en la asistencia sanitaria en el ámbito pediátrico, con la conformación de los equipos de atención primaria y la realización de las actividades que ello conlleva, se traduce en una disminución del riesgo de hospitalización para aquellos niños menores de 2 años cuyo control habitual es realizado por un pediatra perteneciente a un equipo de atención primaria.ObjectiveTo determine whether the structure of primary care teams on carrying out the healthy child health programme leads to a drop in the risk of admission to hospital of children under two, in comparison with the traditional clinic or out-clinic health system.DesignCase-reference epidemiological study.Cases40% of the children under 24 months admitted to paediatric or neonate floors of the Marqués de Valdecilla University Hospital.Reference15% of the recently born children alive in this hospital. Information was gathered through face-to-face interview and by examining health cards. The study ran from April 1995 to May 1996.ResultsChildren under two monitored habitually by a doctor belonging to a primary care team showed a drop in risk of hospital admission for all clinical diagnoses of 0.57 (95% CI, 0.35–0.93), after adjustment due to various confusion factors such as maternal education, social class, ethnic background, mother's age, mother's tobacco consumption, natural breast-feeding at birth, admission at birth. There was a drop of risk of hospital admission for high temperature without apparent cause in those children monitored habitually by a team doctor (adjusted RR = 0.41; 95% CI, 0.19–0.90).ConclusionsThe advantages of the paediatric health care reform with the structuring of the primary care teams and the accompanying activities performed lead to a drop in the risk of hospital admission of those children under two years old who are habitually monitored by a doctor belonging to a primary care team
- …