3,771 research outputs found

    A search for new hot subdwarf stars by means of Virtual Observatory tools

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    Hot subdwarf stars are faint, blue objects, and are the main contributors to the far-UV excess observed in elliptical galaxies. They offer an excellent laboratory to study close and wide binary systems, and to scrutinize their interiors through asteroseismology, as some of them undergo stellar oscillations. However, their origins are still uncertain, and increasing the number of detections is crucial to undertake statistical studies. In this work, we aim at defining a strategy to find new, uncatalogued hot subdwarfs. Making use of Virtual Observatory tools we thoroughly search stellar catalogues to retrieve multi-colour photometry and astrometric information of a known sample of blue objects, including hot subdwarfs, white dwarfs, cataclysmic variables and main sequence OB stars. We define a procedure to discriminate among these spectral classes, particularly designed to obtain a hot subdwarf sample with a low contamination factor. In order to check the validity of the method, this procedure is then applied to two test sky regions: the Kepler FoV and to a test region of around (RA:225, DEC:5) deg. As a result, we obtained 38 hot subdwarf candidates, 23 of which had already a spectral classification. We have acquired spectroscopy for three other targets, and four additional ones have an available SDSS spectrum, which we used to determine their spectral type. A temperature estimate is provided for the candidates based on their spectral energy distribution, considering two-atmospheres fit for objects with clear infrared excess. Eventually, out of 30 candidates with spectral classification, 26 objects were confirmed to be hot subdwarfs, yielding a contamination factor of only 13%. The high rate of success demonstrates the validity of the proposed strategy to find new uncatalogued hot subdwarfs. An application of this method to the entire sky will be presented in a forthcoming work.Comment: 13 pages, 7 figure

    Intestinal colonization due to Escherichia coli ST131: Risk factors and prevalence

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    Background Escherichia coli sequence type 131 (ST131) is a successful clonal group that has dramatically spread during the last decades and is considered an important driver for the rapid increase of quinolone resistance in E. coli. Methods Risk factors for rectal colonization by ST131 Escherichia coli (irrespective of ESBL production) were investigated in 64 household members (18 were colonized) and 54 hospital contacts (HC; 10 colonized) of 34 and 30 index patients with community and nosocomial infection due to these organisms, respectively, using multilevel analysis with a p limit of < 0.1. Result Colonization among household members was associated with the use of proton-pump inhibitors (PPI) by the household member (OR = 3.08; 95% CI: 0.88–10.8) and higher age of index patients (OR = 1.05; 95% CI; 1.01–1.10), and among HC, with being bed-ridden (OR = 21.1; 95% CI: 3.61–160.0) and having a urinary catheter (OR = 8.4; 95% CI: 0.87–76.9). Conclusion Use of PPI and variables associated with higher need of person-to-person contact are associated with increased risk of rectal colonization by ST131. These results should be considered for infection control purposes.Plan Nacional de I + D + i 2013-2016Ministerio de Economía y Competitividad (España)European Development Regional Fund REIPI RD12/0015/0010 REIPI RD16/0016/0001Instituto de Salud Carlos III 070190 AC16/000076-MODERN AC16/AC16/00072-ST131TSJunta de Andalucía CTS5259 CTS21

    Parabolic curves for diffeomorphisms in C2

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    We give a simple proof of the existence of parabolic curves for diffeomorphisms in (C 2 , 0) tangent to the identity with isolated fixed point

    Donepezil alone and combined with intensive language-action therapy on depression and apathy in chronic post-stroke aphasia: A feasibility study

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    This study explored the feasibility and effectiveness of a short-term (10-week) intervention trial using Donepezil administered alone and combined with intensive language action therapy (ILAT) for the treatment of apathy and depression in ten people with chronic post-stroke aphasia. Outcome measures were the Western Aphasia Battery and the Stroke Aphasia Depression Questionnaire-21. Structural magnetic resonance imaging and 18fluorodeoxyglucose positron emission tomography were acquired at baseline and after two endpoints (Donepezil alone and Donepezil-ILAT). The intervention was found to be feasible to implement. Large treatment effects were found. Donepezil alone and combined with ILAT reduced aphasia severity, while apathy and depression only improved with Donepezil-ILAT. Structural and functional neuroimaging data did not show conclusive results but provide hints for future research. Given these overall positive findings on feasibility, language and behavioral benefits, further studies in larger sample sizes and including a placebo-control group are indicated.This work was supported as an independent research grant funded by Pfizer and Eisai. The funders were not involved in the study design, collection, analysis, or interpretation of the data. The work was also supported in part by the Ministerio de Economía, Industria y Competitividad, Instituto de Salud Carlos III, Spain (under Grant: PI16/01514; MLB and GD), and the Junta de Andalucía, Spain (under Grant: P20_00501; GD). MLB has been supported by funds from the European Social Fund (FEDER). LE and FJL-G have been funded by a PhD scholarship from the Spanish Ministry of Education, Culture, and Sport under the FPU program (FPU17/04136; FJL-G: FPU17/04470). DL-B was supported by I + D + i Project Andalusia and European Union Funds (FEDER) (UMA18-FEDERJA-221) and by Ramón y Cajal Program (RYC2020-029495-I) from the Spanish Ministry of Science and Innovation. MT-P has been funded by a postdoctoral fellowship under the program Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI 2020) (DOC_00421). FP and BM were supported by the Deutsche Forschungsgemeinschaft [Pu 97/15-1 and 15-2 to FP, Mo 697/5-2 to BM]. FP was also supported by the European Research Council [ERC-2019-ADG 883811] // Funding for open access charge: Universidad de Málaga / CBUA
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