2,284 research outputs found

    A new concept for the combination of optical interferometers and high-resolution spectrographs

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    The combination of high spatial and spectral resolution in optical astronomy enables new observational approaches to many open problems in stellar and circumstellar astrophysics. However, constructing a high-resolution spectrograph for an interferometer is a costly and time-intensive undertaking. Our aim is to show that, by coupling existing high-resolution spectrographs to existing interferometers, one could observe in the domain of high spectral and spatial resolution, and avoid the construction of a new complex and expensive instrument. We investigate in this article the different challenges which arise from combining an interferometer with a high-resolution spectrograph. The requirements for the different sub-systems are determined, with special attention given to the problems of fringe tracking and dispersion. A concept study for the combination of the VLTI (Very Large Telescope Interferometer) with UVES (UV-Visual Echelle Spectrograph) is carried out, and several other specific instrument pairings are discussed. We show that the proposed combination of an interferometer with a high-resolution spectrograph is indeed feasible with current technology, for a fraction of the cost of building a whole new spectrograph. The impact on the existing instruments and their ongoing programs would be minimal.Comment: 27 pages, 9 figures, Experimental Astronomy; v2: accepted versio

    Safe administration of etoposide phosphate after hypersensitivity reaction to intravenous etoposide

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    Etoposide is commonly used in a variety of malignancies. A well known but rare toxicity are hypersensitivity reactions, usually manifested by chest discomfort, dyspnoea, bronchospasm and hypotension. We report the details of a patient who developed hypersensitivity reactions to intravenous etoposide, but subsequently tolerated the administration of intravenous etoposide phosphate with no sequalae

    A population-based surveillance study on severe acute maternal morbidity (near-miss) and adverse perinatal outcomes in Campinas, Brazil: The Vigimoma Project

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    BACKGROUND: Auditing of sentinel health events based on best-practice protocols has been recommended. This study describes a population-based investigation on adverse perinatal events including severe acute maternal morbidity (near-miss), maternal and perinatal mortality, as a health intervention to help improve the surveillance system. METHODS: From October to December 2005, all cases of maternal death (MD), near-miss (NM), fetal deaths (FD), and early neonatal deaths (END), occurring in Campinas, Brazil, were audited by maternal mortality committees. RESULTS: A total of 4,491 liveborn infants (LB) and 159 adverse perinatal events (35.4/1000 LB) were revised, consisting of 4 MD (89/100.000 LB) and 95 NM (21.1/1000 LB), 23.7 NM for each MD. In addition, 32 FD (7.1/1000 LB) and 28 END (6.2/1000 LB) occurred. The maternal death/near miss rate was 23.7:1. Some delay in care was recognized for 34%, and hypertensive complications comprised 57.8% of the NM events, followed by postpartum hemorrhage. CONCLUSION: Auditing near miss cases expanded the understanding of the spectrum from maternal morbidity to mortality and the importance of promoting adhesion to clinical protocols among maternal mortality committee members. Hypertensive disorders and postpartum hemorrhage were identified as priority topics for health providers training, and organization of care

    Asteroseismology and Interferometry

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    Asteroseismology provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Recent developments, including the first systematic studies of solar-like pulsators, have boosted the impact of this field of research within Astrophysics and have led to a significant increase in the size of the research community. In the present paper we start by reviewing the basic observational and theoretical properties of classical and solar-like pulsators and present results from some of the most recent and outstanding studies of these stars. We centre our review on those classes of pulsators for which interferometric studies are expected to provide a significant input. We discuss current limitations to asteroseismic studies, including difficulties in mode identification and in the accurate determination of global parameters of pulsating stars, and, after a brief review of those aspects of interferometry that are most relevant in this context, anticipate how interferometric observations may contribute to overcome these limitations. Moreover, we present results of recent pilot studies of pulsating stars involving both asteroseismic and interferometric constraints and look into the future, summarizing ongoing efforts concerning the development of future instruments and satellite missions which are expected to have an impact in this field of research.Comment: Version as published in The Astronomy and Astrophysics Review, Volume 14, Issue 3-4, pp. 217-36

    Patients' Costs and Cost-Effectiveness of Tuberculosis Treatment in DOTS and Non-DOTS Facilities in Rio de Janeiro, Brazil

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    Costs of tuberculosis diagnosis and treatment may represent a significant burden for the poor and for the health system in resource-poor countries.The aim of this study was to analyze patients' costs of tuberculosis care and to estimate the incremental cost-effectiveness ratio (ICER) of the directly observed treatment (DOT) strategy per completed treatment in Rio de Janeiro, Brazil.We interviewed 218 adult patients with bacteriologically confirmed pulmonary tuberculosis. Information on direct (out-of-pocket expenses) and indirect (hours lost) costs, loss in income and costs with extra help were gathered through a questionnaire. Healthcare system additional costs due to supervision of pill-intake were calculated considering staff salaries. Effectiveness was measured by treatment completion rate. The ICER of DOT compared to self-administered therapy (SAT) was calculated.DOT increased costs during the treatment phase, while SAT increased costs in the pre-diagnostic phase, for both the patient and the health system. Treatment completion rates were 71% in SAT facilities and 79% in DOT facilities. Costs per completed treatment were US194forpatientsandU 194 for patients and U 189 for the health system in SAT facilities, compared to US336andUS 336 and US 726 in DOT facilities. The ICER was US$ 6,616 per completed DOT treatment compared to SAT.Costs incurred by TB patients are high in Rio de Janeiro, especially for those under DOT. The DOT strategy doubles patients' costs and increases by fourfold the health system costs per completed treatment. The additional costs for DOT may be one of the contributing factors to the completion rates below the targeted 85% recommended by WHO
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