576 research outputs found

    Astrophysical Probes of Fundamental Physics

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    I review the theoretical motivation for varying fundamental couplings and discuss how these measurements can be used to constrain a number of fundamental physics scenarios that would otherwise be inacessible to experiment. As a case study I will focus on the relation between varying couplings and dark energy, and explain how varying coupling measurements can be used to probe the nature of dark energy, with important advantages over the standard methods. Assuming that the current observational evidence for varying α\alpha and μ\mu is correct, a several-sigma detection of dynamical dark energy is feasible within a few years, using currently operational ground-based facilities. With forthcoming instruments like CODEX, a high-accuracy reconstruction of the equation of state may be possible all the way up to redshift z4z\sim4.Comment: Invited Review talk at the ESO Precision Spectroscopy in Astrophysics conference, to appear in the proceeding

    Potential Impact of Climate Change on Suspended Sediment Yield in NW Spain: A Case Study on the Corbeira Catchment

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    [Abstract] Soil losses and the subsequent sediment delivery constitute significant environmental threats. Climate change is likely to have an impact on the availability of water and therefore on sediment yield in catchments. In this context, quantifying the sediment response to an increased atmospheric CO2 concentration and climate change is of utmost importance to the proper management of rural catchments. However, quantitative assessment of climate change impact remains a complex task. In this study, the potential medium (2031–2060) and long-term (2069–2098) impacts of projected changes of temperature, rainfall and CO2 concentration on sediment yield in a small rural catchment located in NW Spain were evaluated using the Soil and Water Assessment Tool (SWAT) model. Climate change scenarios were created using future climate data projected by regional climate models from the ENSEMBLES project and two CO2 concentration scenarios (550 and 660 ppm). The results showed that climate change would have a noticeable impact on suspended sediment if the forecast temperature, rainfall and CO2 concentration changes included in this study were met. Overall, suspended sediment is expected to decrease (2031–2060: −11%, 2069–2098: −8%) compared to the baseline period (1981–2010), mainly due to decreased streamflow. However, an increase in sediment transport in winter is predicted, possibly associated with increased erosion in cultivated areas (11%–17%), suggesting that, at this time of the year, the effect of soil detachment prevails over sediment transport capacity. Consequently, management practices aimed at reducing soil erosion in cultivated areas should be carried out, because these are the main source of sediment in the study area.Galicia. Consellería de Economía e Industria; 10MDS103031Ministerio de Economía y Competitividad; CGL2014-56907-

    Influencia del pick and roll en el juego de ataque en baloncesto de alto nivel

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    El objetivo de este estudio fue caracterizar las acciones del pickand roll y su influencia en el juego en baloncesto de alto nivel. Se analizóla eficacia táctica y de marcador en función de distintos factores queinciden en las situaciones de juego mediante un diseño observacional nomotético,puntual y multidimensional en 18 equipos de la liga ACB debaloncesto. Un instrumento observacional ad hoc (VTP&R) fue validadopor un panel de 20 expertos de alto nivel y se comprobó la fiabilidad en laobservación por parte de los investigadores. El análisis de datos se realizómediante el análisis secuencial de retardos, el análisis de coordenadaspolares y los estadísticos descriptivos cuantitativos. Del total de accionesanalizadas (n=3895), el 25,3% se corresponden a pick and roll (n=984). Soloel 36,3% de las acciones de pick and roll se han mostrado eficaces en elmarcador, mientras que el 85,7% lo son tácticamente. La interpretaciónde los resultados muestra el interés en complementar el análisis del juegoen baloncesto a través de los mixed methods. La posibilidad de determinarqué acciones se realizan en cada momento del partido y de qué manera seejecutan, así como establecer patrones de respuesta táctica en función delos distintos factores que intervienen en el juego, justifica la utilidad de losresultados aquí obtenidos y se concluye el interés en incorporar las distintastécnicas analíticas de la metodología observacional a los procesos de análisisdel baloncesto

    III Ciclo de Conferências do Conselho Técnico-Científico : temas atuais em investigação

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    A obra é constituída pelos resumos das comunicações apresentadas pelos docentes da Escola Superior Agrária do Instituto Politécnico de Castelo Branco e são referentes aos projetos de investigação nos quais estão envolvidos.O Conselho Técnico-Científico da Escola Superior Agrária (ESA), eleito para o biénio 2014-2016, tomou posse no dia 27 de março de 2014. Uma das iniciativas previstas no seu Plano de Atividades consistia no desenvolvimento de ações de divulgação de atividades técnico-científicas, com intervenção da ESA. Neste âmbito promoveu-se o III Ciclo de Conferências do Conselho Técnico-Científico, através do qual se procurou fomentar a difusão do conhecimento e valorizar os resultados de trabalhos de investigação e de experimentação, através da divulgação do seu contributo para o desenvolvimento tecnológico e da inovação de empresas e produtos. Com a presente publicação pretende dar-se a conhecer a um auditório mais vasto a informação apresentada e debatida publicamente, assim como promover uma maior colaboração entre entidades e instituições em ações suscetíveis de contribuir para o aumento da competitividade e do espírito empreendedor de empresas associadas ao setor agrícola e agroindustrial

    Models of quintessence coupled to the electromagnetic field and the cosmological evolution of alpha

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    We study the change of the effective fine structure constant in the cosmological models of a scalar field with a non-vanishing coupling to the electromagnetic field. Combining cosmological data and terrestrial observations we place empirical constraints on the size of the possible coupling and explore a large class of models that exhibit tracking behavior. The change of the fine structure constant implied by the quasar absorption spectra together with the requirement of tracking behavior impose a lower bound of the size of this coupling. Furthermore, the transition to the quintessence regime implies a narrow window for this coupling around 10510^{-5} in units of the inverse Planck mass. We also propose a non-minimal coupling between electromagnetism and quintessence which has the effect of leading only to changes of alpha determined from atomic physics phenomena, but leaving no observable consequences through nuclear physics effects. In doing so we are able to reconcile the claimed cosmological evidence for a changing fine structure constant with the tight constraints emerging from the Oklo natural nuclear reactor.Comment: 13 pages, 10 figures, RevTex, new references adde

    Photocatalytic ozonation of urban wastewater and surface water using immobilized TiO2 with LEDs: Micropollutants, antibiotic resistance genes and estrogenic activity

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    Photocatalytic ozonation was employed for the first time in continuous mode with TiO2-coated glass Raschig rings and light emitting diodes (LEDs) to treat urban wastewater as well as surface water collected from the supply area of a drinking water treatment plant (DWTP). Different levels of contamination and types of contaminants were considered in this work, including chemical priority substances (PSs) and contaminants of emerging concern (CECs), as well as potential human opportunistic antibiotic resistant bacteria and their genes (ARB&ARG). Photocatalytic ozonation was more effective than single ozonation (or even than TiO2 catalytic ozonation) in the degradation of typical reaction by-products (such as oxalic acid), and more effective than photocatalysis to remove the parent micropollutants determined in urban wastewater. In fact, only fluoxetine, clarithromycin, erythromycin and 17-alpha-ethinylestradiol (EE2) were detected after photocatalytic ozonation, by using solid-phase extraction (SPE) pre-concentration and LC-MS/MS analysis. In surface water, this treatment allowed the removal of all determined micropollutants to levels below the limit of detection (0.01-0.20 ng L(-1)). The efficiency of this process was then assessed based on the capacity to remove different groups of cultivable microorganisms and housekeeping (16S rRNA) and antibiotic resistance or related genes (intI1, blaTEM, qnrS, sul1). Photocatalytic ozonation was observed to efficiently remove microorganisms and ARGs. Although after storage total heterotrophic and ARB (to ciprofloxacin, gentamicin, meropenem), fungi, and the genes 16S rRNA and intI1, increased to values close to the pre-treatment levels, the ARGs (blaTEM, qnrS and sul1) were reduced to levels below/close to the quantification limit even after 3-days storage of treated surface water or wastewater. Yeast estrogen screen (YES), thiazolyl blue tetrazolium reduction (MTT) and lactate dehydrogenase (LDH) assays were also performed before and after photocatalytic ozonation to evaluate the potential estrogenic activity, the cellular metabolic activity and the cell viability. Compounds with estrogenic effects and significant differences concerning cell viability were not observed in any case. A slight cytotoxicity was only detected for Caco-2 and hCMEC/D3 cell lines after treatment of the urban wastewater, but not for L929 fibroblasts.info:eu-repo/semantics/acceptedVersio

    Development of electrospun photocatalytic TiO2-polyamide-12 nanocomposites

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    Titanium dioxide (TiO2) in different forms such as films, fibers or particles are being extensively studied for removal of contaminants from aquatic environments due to its outstanding photocatalytic activity. This work reports the development of TiO2-polyamide 12 electrospun fiber mats. A systematic study on the influence of electrospun processing parameters on polymer fiber morphology was performed. It was observed that the average fiber diameter is mainly influenced by polymer concentration and average fiber diameters between 404 ± 82 nm and 1442 ± 360 nm were obtained. Polyamide-12 (PA-12) was used as a polymer matrix and electrospun with 0, 10 and 20 wt% of TiO2. It was observed that the filler does not change the average fiber diameter, being similar to that observed for neat PA-12 fibers processed under the same experimental conditions. The TiO2 were particles dispensed not only in the bulk of the polymeric matrix but also on the surface of the fibers, especially for the samples with higher filler contents. Neat and nanocomposite electrospun samples show a hydrophobic behavior and a degree of crystallinity of ~25%. The photocatalytic performance of the processed samples was measured by following the degradation capability of a chosen dye, methylene blue (MB). Results show that the nanocomposite samples have a remarkable photocatalytic activity, especially the one with a higher load of TiO2 particles (20 wt%), with all MB being removed from the solution after 100 min.This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/ UI607/2014, and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnol ogico e Brazil). The authors also thank funding from “Matepro eOptimizing Materials and Processes”, ref. NORTE- 07-0124-FEDER-000037”, co-funded by the “Programa Operacional Regional do Norte” (ON.2 e O Novo Norte), under the “Quadro de Refer^encia Estrat egico Nacional” (QREN), through the “Fundo Europeu de Desenvolvimento Regional” (FEDER). PM thanks the FCT for the, SFRH/BD/98616/2013 grant. VS and SLM also thank support from the COST Action MP1206 “Electrospun Nano-fibers for bio inspired composite materials and innovative industrial applications”. VS thanks the EIS Faculty at UOW for the starting grant

    Future Opportunities for IoT to Support People with Parkinson’s

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    Recent years have seen an explosion of internet of things (IoT) technologies being released to the market. There has also been an emerging interest in the potentials of IoT devices to support people with chronic health conditions. In this paper, we describe the results of engagements to scope the future potentials of IoT for supporting people with Parkinson’s. We ran a 2-day multi-disciplinary event with professionals with expertise in Parkinson’s and IoT, to explore the opportunities, challenges and benefits. We then ran 4 workshops, engaging 13 people with Parkinson’s and caregivers, to scope out the needs, values and desires that the community has for utilizing IoT to monitor their symptoms. This work contributes a set of considerations for future IoT solutions that might support people with Parkinson’s in better understanding their condition, through the provision of objective measurements that correspond to their, currently unmeasured, subjective experiences

    Cosmology and fundamental physics with the ELT-ANDES spectrograph

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    State-of-the-art 19th century spectroscopy led to the discovery of quantum mechanics, and 20th century spectroscopy led to the confirmation of quantum electrodynamics. State-of-the-art 21st century astrophysical spectrographs, especially ANDES at ESO’s ELT, have another opportunity to play a key role in the search for, and characterization of, the new physics which is known to be out there, waiting to be discovered. We rely on detailed simulations and forecast techniques to discuss four important examples of this point: big bang nucleosynthesis, the evolution of the cosmic microwave background temperature, tests of the universality of physical laws, and a real-time model-independent mapping of the expansion history of the universe (also known as the redshift drift). The last two are among the flagship science drivers for the ELT. We also highlight what is required for the ESO community to be able to play a meaningful role in 2030s fundamental cosmology and show that, even if ANDES only provides null results, such ‘minimum guaranteed science’ will be in the form of constraints on key cosmological paradigms: these are independent from, and can be competitive with, those obtained from traditional cosmological probes
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