Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Ações públicas para o controle do câncer de mama no Brasil: revisão integrativa

RESUMO Objetivo: analisar a produção científica sobre "câncer de mama" no período de 2002 a 2013 e identificar quais são as políticas públicas de rastreamento e diagnóstico precoce para o câncer de mama. Método: trata-se de uma revisão integrativa da literatura realizada nas bases de dados MEDLINE, LILACS, SciELO e Google Acadêmico. Utilizou-se como critérios de inclusão: ano e período de publicação; disponibilidade do artigo na íntegra; publicação no Brasil; e o cruzamento entre os descritores Câncer de Mama, Atenção Primária à Saúde, Programas de Rastreamento e Detecção Precoce de Câncer. Resultados: após análise, obtiveram-se quatro (4) categorias temáticas: autoexame das mamas, exame clínico das mamas, mamografia e fatores que dificultam a adesão ao rastreamento. Conclusão: há déficits de conhecimento dos profissionais de saúde sobre a área, indicando a necessidade de realização de outros estudos sobre a temática abordada e maior investimento na educação continuada dos profissionais