241 research outputs found

    A study of the interacting binary V 393 Scorpii

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    We present high resolution J-band spectroscopy of V 393 Sco obtained with the CRIRES at the ESO Paranal Observatory along with a discussion of archival IUE spectra and published broad band magnitudes. The best fit to the spectral energy distribution outside eclipse gives T1T_{1}= 19000 ±\pm 500 KK for the gainer, T2T_{2}= 7250 ±\pm 300 KK for the donor, E(BV)E(B-V)= 0.13 ±\pm 0.02 mag. and a distance of dd= 523 ±\pm 60 pc, although circumstellar material was not considered in the fit. We argue that V 393 Sco is not a member of the open cluster M7. The shape of the He I 1083 nm line shows orbital modulations that can be interpreted in terms of an optically thick pseudo-photosphere mimicking a hot B-type star and relatively large equatorial mass loss through the Lagrangian L3 point during long cycle minimum. IUE spectra show several (usually asymmetric) absorption lines from highly ionized metals and a narrow Lα\alpha emission core on a broad absorption profile. The overall behavior of these lines suggests the existence of a wind at intermediate latitudes. From the analysis of the radial velocities we find M2/M1M_{2}/M_{1}= 0.24 ±\pm 0.02 and a mass function of ff= 4.76 ±\pm 0.24 M\odot. Our observations favor equatorial mass loss rather than high latitude outflows as the cause for the long variability.Comment: 13 pages, 14 figures, 7 tables. Accepted for publication in MNRAS, main journa

    New development: The ethics of accounting information manipulation in the political arena

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    ABSTRACT This article explores ethical issues of accounting information manipulation (AIM) in the political arena. After conceptualizing AIM, including its drivers, techniques, contextualities and impacts, the authors discuss underlying tensions between various types of values that emerge as a trigger for applying AIM. In that respect a distinction is made between values at the societal, organizational and individual level, such as, respectively, sustainability, transparency and honesty, and additionally between private values related to personal gain and public values

    The O-type eclipsing binary SZ Cam revisited

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    We analyse new spectra of the multiple system SZ Cam because previous studies found different values of the primary radial velocity amplitude. The older solutions of light curves also have different ratios of secondary to primary luminosity as inferred from the observed equivalent widths of spectral lines. We therefore reanalyse the light curves of the eclipsing pair. Only the light curve derived by Wesselink has a solution that agrees with the observed equivalent width ratio. The resulting parameters of the binary are discussed. Masses of M1=16.6M_1=16.6 and M2=11.9M_2=11.9 M_{\odot}, and radii R1=9.4R_1=9.4 and R2=5.4R_2=5.4 R_{\odot} are derived. We point out that radial velocities measured with the CCF method can be misleading when the method is applied to multiple systems with complex line blends. New radial velocities are also obtained for the visual component ADS 2984 A (HD 25639).Comment: Astronomy and Astrophysics, accepte

    Implementation lessons learnt when trialling palliative care interventions in the intensive care unit: relationships between determinants, implementation strategies, and models of delivery-a systematic review protocol

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    BACKGROUND: Heterogeneity amongst palliative care interventions in the intensive care unit (ICU) and their outcomes has meant that, even when found to be effective, translation of evidence into practice is hindered. Previous evidence reviews have suggested that the field of ICU-based palliative care would benefit from well-designed, targeted interventions, with explicit knowledge translation research demonstrating valid implementation strategies. Reviewing effectiveness studies alongside process evaluations for these interventions will give insight into the implementation barriers or constraints identified, and the implementation strategies adopted. METHODS: A systematic review to identify and synthesise knowledge on how models of integrating palliative care into the ICU have been implemented and provide critical recommendations for successful future development and implementation of complex interventions in the field. The search will be carried out using MEDLINE, Embase, Cochrane, CINAHL, and PsycINFO. The search strategy will combine terms related to palliative care, intensive care, and implementation. Only full-text articles will be considered and conference abstracts excluded. There will be no date or language restrictions. The Implementation Research Logic Model will be used as a framework for synthesis. Findings will be reported following the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines. DISCUSSION: This review will provide understanding of implementation facilitators, barriers, and strategies, when employing palliative care interventions within the ICU. This will provide valuable recommendations for successful future development of complex interventions using implementation frameworks or theories. This can increase the potential for sustained change in practice, reduce heterogeneity in interventions, and therefore help produce measurable and comparable outcomes. SYSTEMATIC REVIEW REGISTRATION: International Prospective Register of Systematic reviews PROSPERO (CRD42022311052)

    On-line Estimation of the Ventilation Rate of Greenhouses: a System Theoretical Approach

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    Using an unknown input observer, with an output linearising feedback, an on-line estimator for the ventilation flow or rate is developed for natural ventilated greenhouses. The paper shows how to design, implement and tune such an estimator in practice and shows that it performs well. Furthermore the practical value for the grower is discussed

    Analysis of the MOST light curve of the heavily spotted K2IV component of the single-line spectroscopic binary II Pegasi

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    Continuous photometric observations of the visible component of the single-line, K2IV spectroscopic binary II Peg carried out by the MOST satellite during 31 consecutive days in 2008 have been analyzed. On top of spot-induced brightness modulation, eleven flares were detected of three distinct types characterized by different values of rise, decay and duration times. The flares showed a preference for occurrence at rotation phases when the most spotted hemisphere is directed to the observer, confirming previous similar reports. An attempt to detect a grazing primary minimum caused by the secondary component transiting in front of the visible star gave a negative result. The brightness variability caused by spots has been interpreted within a cold spot model. An assumption of differential rotation of the primary component gave a better fit to the light curve than a solid-body rotation model.Comment: Accepteed to MNRA

    A search for p-modes and other variability in the binary system 85 Pegasi using MOST photometry

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    Context: Asteroseismology has great potential for the study of metal-poor stars due to its sensitivity to determine stellar ages. Aims: Our goal was to detect p-mode oscillations in the metal-poor sub-dwarf 85 Peg A and to search for other variability on longer timescales. Methods: We have obtained continuous high-precision photometry of the binary system 85 Pegasi with the MOST space telescope in two seasons (2005 & 2007). Furthermore, we redetermined vsini for 85 Peg A using high resolution spectra obtained through the ESO archive, and used photometric spot modeling to interpret long periodic variations. Results: Our frequency analysis yields no convincing evidence for p-modes significantly above a noise level of 4 ppm. Using simulated p-mode patterns we provide upper RMS amplitude limits for 85 Peg A. The light curve shows evidence for variability with a period of about 11 d and this periodicity is also seen in the follow up run in 2007; however, as different methods to remove instrumental trends in the 2005 run yield vastly different results, the exact shape and periodicity of the 2005 variability remain uncertain. Our re-determined vsini value for 85 Peg A is comparable to previous studies and we provide realistic uncertainties for this parameter. Using these values in combination with simple photometric spot models we are able to reconstruct the observed variations. Conclusions: The null-detection of p-modes in 85 Peg A is consistent with theoretical values for pulsation amplitudes in this star. The detected long-periodic variation must await confirmation by further observations with similar or better precision and long-term stability. If the 11 d periodicity is real, rotational modulation of surface features on one of the components is the most likely explanation.Comment: 11 pages, 9 figures, accepted for publication in A&
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