23 research outputs found

    The intermediate polar cataclysmic variable GK Persei 120 years after the nova explosion: a first dynamical mass study

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    We present a dynamical study of the intermediate polar and dwarf nova cataclysmic variable GK Persei (Nova Persei 1901) based on a multisite optical spectroscopy and R-band photometry campaign. The radial velocity curve of the evolved donor star has a semi-amplitude K-2 = 126.4 +/- 0.9 km s(-1) and an orbital period P = 1.996872 +/- 0.000009 d. We refine the projected rotational velocity of the donor star to v(rot) sin i = 52 +/- 2 km s(-1) that, together with K-2, provides a donor star to white dwarf mass ratio q = M-2/M-1 = 0.38 +/- 0.03. We also determine the orbital inclination of the system by modelling the phase-folded ellipsoidal light curve and obtain i = 67 degrees +/- 5 degrees. The resulting dynamical masses are M-1 = 1.03(-0.11)(+0.16) M-circle dot and M-2 = 0.39(-0.06)(+0.07) M-circle dot at 68 per cent confidence level. The white dwarf dynamical mass is compared with estimates obtained by modelling the decline light curve of the 1901 nova event and X-ray spectroscopy. The best matching mass estimates come from the nova light curve models and an X-ray data analysis that uses the ratio between the Alfven radius in quiescence and during dwarf nova outburst

    Hard-state Accretion Disk Winds from Black Holes: The Revealing Case of MAXI J1820+070

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    We report on a detailed optical spectroscopic follow-up of the black hole (BH) transient MAXI J1820+070 (ASASSN-18ey). The observations cover the main part of the X-ray binary outburst, when the source alternated between hard and soft states following the classical pattern widely seen in other systems. We focus the analysis on the He I emission lines at 5876 and 6678 angstrom, as well as on H alpha. We detect clear accretion disk wind features (P-Cyg profiles and broad emission line wings) in the hard state, both during outburst rise and decay. These are not witnessed during the several months long soft state. However, our data suggest that the visibility of the outflow might be significantly affected by the ionization state of the accretion disk. The terminal velocity of the wind is above similar to 1200 km s(-1), which is similar to outflow velocities derived from (hard-state) optical winds and (soft-state) X-ray winds in other systems. The wind signatures, in particular the P-Cyg profiles, are very shallow, and their detection has only been possible thanks to a combination of source brightness and intense monitoring at very high signal-to-noise. This study indicates that cold, optical winds are most likely a common feature of BH accretion, and therefore, that wind-like outflows are a general mechanism of mass and angular momentum removal operating throughout the entire X-ray binary outburst

    Prácticas del enfermero en el contexto de la atención básica: scoping review

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    Objective: to identify and categorize the practices performed by nurses working in Primary Health Care and Family Health Strategy Units in light of responsibilities established by the profession’s legal and programmatic frameworks and by the Brazilian Unified Health System. Method: a scoping review was conducted in the following databases: LILACS, IBECS, BDENF, CINAHL and MEDLINE, and the Cochrane and SciELO libraries. Original research papers written by nurses addressing nursing practices in the primary health care context were included. Results: the review comprised 30 studies published between 2005 and 2014. Three categories emerged from the analysis: practices in the service; practices in the community; and management and education practices. Conclusion: the challenges faced by nurses are complex, as care should be centered on the population’s health needs, which requires actions at other levels of clinical and health responsibility. Brazilian nursing has achieved important advancements since the implementation of policies intended to reorganize work. There is, however, a need to shift work processes from being focused on individual procedures to being focused on patients so that an enlarged clinic is the ethical-political imperative guiding the organization of services and professional intervention.Objetivo: identificar e categorizar as práticas exercidas pelos enfermeiros junto às Unidades Básicas e às Equipes de Saúde da Família, à luz das atribuições previstas pelos marcos legais e programáticos da profissão e do Sistema Único de Saúde. Método: realizou-se uma revisão da literatura com o método scoping review, nas bases LILACS, IBECS, BDENF, CINAHL e MEDLINE, e nas bibliotecas Cochrane e SciELO. Incluíram-se artigos de pesquisa original, produzidos com enfermeiros, sobre as práticas de enfermagem no contexto dos cuidados de saúde primários. Resultados: a revisão abrangeu trinta estudos publicados entre 2005 e 2014. Da análise, resultaram três categorias: práticas no serviço, práticas na comunidade e práticas de gestão e formação. Conclusão: os desafios dos enfermeiros são complexos, posto que o cuidado deve estar centrado nas necessidades de saúde da população, o que remete à ação para outros níveis de responsabilidade clínica e sanitária. A enfermagem brasileira mostra importantes avanços desde a implantação das políticas de reorganização do trabalho. Necessita, entretanto, avançar no que se refere ao deslocamento dos processos de trabalho, focados em procedimentos individuais, para um processo mais voltado aos usuários, onde a clínica ampliada seja o imperativo ético-político da organização dos serviços e da intervenção profissional.Objetivo: identificar y categorizar las prácticas ejercidas por los enfermeros en las Unidades Básicas y los Equipos de Salud de la Familia, desde el punto de vista de las atribuciones previstas por los marcos legales y programáticos de la profesión y del Sistema Único de la Salud. Método: se realizó una revisión de la literatura con el método scoping review, en las bases LILACS, IBECS, BDENF, CINAHL y MEDLINE, y en las bibliotecas Cochrane y SciELO. Se incluyeron artículos de investigación original, producidos con enfermeros, sobre las prácticas de enfermería en el contexto de los cuidados de salud primarios. Resultados: la revisión abarcó treinta estudios publicados entre 2005 y 2014. Del análisis, resultaron tres categorías: prácticas en el servicio; prácticas en la comunidad; y, prácticas de administración y formación. Conclusión: los desafíos de los enfermeros son complejos, ya que el cuidado debe estar centrado en las necesidades de salud de la población, lo que conduce a la acción para otros niveles de responsabilidad clínica y sanitaria. La enfermería brasileña muestra importantes avances a partir de la implantación de las políticas de reorganización del trabajo. Necesita, entre tanto, avanzar en lo que se refiere al desplazamiento de los procesos de trabajo, enfocados en procedimientos individuales, para un proceso más dirigido a los usuarios, en donde la clínica ampliada sea el imperativo ético político de la organización de los servicios y de la intervención profesional.info:eu-repo/semantics/publishedVersio

    Randomized clinical trials of dental bleaching – Compliance with the CONSORT Statement: a systematic review

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    Hard-state accretion disk winds from black holes: the revealing case of MAXI J1820+070

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    We report on a detailed optical spectroscopic follow-up of the black hole (BH) transient MAXI J1820+070 (ASASSN-18ey). The observations cover the main part of the X-ray binary outburst, when the source alternated between hard and soft states following the classical pattern widely seen in other systems. We focus the analysis on the He i emission lines at 5876 and 6678 as well as on Hα. We detect clear accretion disk wind features (P-Cyg profiles and broad emission line wings) in the hard state, both during outburst rise and decay. These are not witnessed during the several months long soft state. However, our data suggest that the visibility of the outflow might be significantly affected by the ionization state of the accretion disk. The terminal velocity of the wind is above ∼1200 km s , which is similar to outflow velocities derived from (hard-state) optical winds and (soft-state) X-ray winds in other systems. The wind signatures, in particular the P-Cyg profiles, are very shallow, and their detection has only been possible thanks to a combination of source brightness and intense monitoring at very high signal-to-noise. This study indicates that cold, optical winds are most likely a common feature of BH accretion, and therefore, that wind-like outflows are a general mechanism of mass and angular momentum removal operating throughout the entire X-ray binary outburst. -
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