bluuebunny/crossref_metadata_2025_split huggingface dataset:
VP54 Digital Tools For More Efficient Conduct Of RCTs: Trials Unit Survey
Authors: Nuttall Jacqui , Lane Athene , Blatch-Jones Amanda , Griffiths Gareth , Wyatt Jeremy 
Published: December 2019

IntroductionRecruitment of participants to, and their retention in, Randomized Controlled Trials (RCTs) is a key determinant of research efficiency, but is challenging. Digital tools and media are increasingly used to reduce costs, waste and delays in the conduct and delivery of research. The aim of this UK Clinical Trials Unit (CTU) survey was to identify which digital recruitment and retention tools are being used to support RCTs, their benefits and success characteristics.MethodsA survey was sent to all UK Clinical Research Collaboration (UKCRC)-registered CTUs with a webinar to help increase completion. A logic model and definitions of a “digital tool” were developed by iterative refinement by project team members, the Advisory Board (NIHR Research Design service, NHS Trust, NIHR Clinical Research Networks and patient input) and CTUs.ResultsA total of 24/52 (46%) CTUs responded, 6 (25%) of which stated no prior use. Database screening tools (e.g. CPRD, EMIS) were the tool most widely used (45%) for recruitment and were considered very effective (67%). The most mentioned success criteria were saving GP time and reaching more patients. Social media was second (27%), but estimated effectiveness varied considerably, with only 17% stating very effective. Fewer retention tools were used, with SMS / email reminders reported most (10/15 67%), but certainty about effectiveness varied. A detailed definition on what constitutes a digital tool with examples and a logic model showing relationships between the resources, activities, outputs and outcomes for digital tools was developed.ConclusionsDatabase screening tools are the most commonly used digital tool for recruitment, with clear success criteria and certainty about effectiveness. Our detailed definition of what constitutes a digital tool, with examples, will inform the NIHR research community about choices and help them identify potential tools to support recruitment and retention.
VP83 Health Economics Distance Learning For Healthcare Workers In Brazil
Authors: Bagattini Ângela , Marçal dos Santos Adélia , Juk Juliana , Soares Renata , Piola Sergio , Toscano Cristiana 
Published: December 2019

IntroductionDespite increased healthcare systems costs, limited opportunities for health economics training are available to healthcare professionals. From 2016-2018, with a grant from the Brazilian Ministry of Health, the Federal University of Goias with 7 other universities, implemented the distance learning Postgraduate Certificate in Health Economics for Health Care Professionals (PCHE) aimed at enhancing technical capacity of professionals working in the Brazilian Public Healthcare System (SUS).MethodsThis is a descriptive and qualitative assessment of the PCHE implemented in Brazil 88 healthcare professionals working in SUS and involved in decision making in all levels of managament were enrolled in a health economics training, through long-distance learning strategy. We present course metrics, describe its workload, content, modalities and structure of training.ResultsPCHE was structured with 3-day workshops introducing each of the modules, during which students were also evaluated regarding the previous module content. With a total workload of 360 hours, structured in four modules: Public Health and Epidemiology; Introduction to health economics and healthcare funding; Management of healthcare resources; and Healthcare economic evaluation. The module coordinator was resposible for supervision of course materials development, workshop, distance based tutoring activities, and evaluation. Course material included theorethical content and practical tools for economic evaluation and health technology assessment in the workplace, applying problem-based learning strategies. Certificates were granted to students with 75 percent presence and approved in all modules, and final papers approved by an examination board. Each module was completed in 8 weeks (90 hours/module). Within groups of 20 students, tutors performed communication witn chats twice weekly and discussion forums by topic.. A total of 88 students were enrolled. Drop-out rate was 35.2 percent (n = 31). Additional 10 students did not pass the exams. In total, 47 students completed the training.ConclusionsHealth economics training through distance learning is a more efficient use of resources with good results.
VP95 Getting the Best Of 3 Ways-Merging EUnetHTA GRADE And Cochrane Guides
Authors: Ballini Luciana , Formoso Giulio , Bassi Maria Chiara , Bonvicini Laura , Bottazzi Paolo , Rossi Paolo Giorgi , Venturelli Francesco , Vicentini Massimo 
Published: December 2019

IntroductionEuropean cooperation in Health Technology Assessment (HTA) requires joint assessments to be of high quality, providing findings transferable into national HTA report. To this aim, we piloted the combining of methodological guidance of EUnetHTA for Relative Effectiveness Assessment (REA), GRADE for selection/rating of outcomes and assessing quality of evidence, and Cochrane for Systematic Reviews, while carrying out a collaborative REA on Femtosecond Laser Assisted versus Standard Cataract Surgery.MethodsWhile developing the collaborative REA, we used the three organizations’ handbooks, templates and tools for Scope, Project Plan (PP), Summary of Findings, Effectiveness (EFF) and Safety (SAF) domains. We structured the PP according to the EUnetHTA template and added detailed methods on EFF and SAF systematic reviews, as per Cochrane Handbook. For the Scope we convened a multidisciplinary panel for selection and rating of importance of outcomes and clinically significant difference, using the GRADEpro platform. We developed the complete report adopting the EUnetHTA REA Core Model. We used Cochrane's tool Revman to assess risk of bias of included studies for each outcome, and to carry out metanalyses. We applied the GRADE approach to assess quality of evidence for each outcome and to express level of certainty in the estimates. We used the Cochrane handbook's guidance for structuring a scientific abstract and a Plain Language Summary to integrate the Summary of Findings.ResultsThe PP resulted in a detailed scientific and operational protocol, receiving extensive and constructive internal and external peer review. Reporting of EFF and SAF domains followed EUnetHTA Assessment Elements while keeping the order of stakeholders' rating of outcomes’ importance. Graphic representation of risk of bias for each outcome contributed to immediacy of the data quality assessment and transparency of the judgement on certainty. The scientific abstract and the Plain Language Summary, facilitated the external dissemination of results.ConclusionsMerging of the three most important methodological contributions in the field proved successful without altering the distinctive trait of the REA.
VP101 Intrauterine Surgical Interventions: A Rapid Review
Authors: de Aguiar Aurelina Aguiar , Farinasso Cecilia , Rego Daniela , Simões Luciana , Leão Camara , Silva Roberta Borges , Gomes Dalila , Sachetti Camile Giaretta 
Published: December 2019

IntroductionAdverse conditions during pregnancy, such as myelomeningocele (MMC), fetal-fetal transfusion syndrome (STFF) and congenital heart disease (CHD) not only significantly increase the risk of fetal death, but also increase the occurrence of severe postnatal sequelae.MethodsWe conducted a rapid review of the efficacy and safety of intrauterine interventions in MMC, STFF and DCC in comparison to traditional interventions. We searched Pubmed via Medline, Cochrane Library and Center for Reviews and Dissemination databases using the terms indexed and synonyms for each intervention.ResultsFor STFF, the available scientific evidence indicates that laser ablation is effective and presents better outcomes when compared to other interventions, such as high overall survival rate, better perinatal outcomes and less chance of brain injury. Even though intrauterine interventions in CHD present high rates of live births, high neonatal mortality rates are also reported. Evidence on the efficacy and safety of intrauterine surgical interventions for myelomeningocele and CHD is inconclusive. Regarding myelomeningocele, no significant differences were observed for the outcomes of postnatal mortality, rate of ventriculostomy placement, reversal of posterior brain herniation, motor response and placental rupture.ConclusionsThere is no consensus regarding the efficacy and safety of intrauterine surgical interventions for myelomeningocele and CHD. Regarding STFF, laser ablation is accepted as an effective intervention. It is necessary to conduct prospective studies in order to evaluate the effect of these interventions, considering the specifications of each condition and the ethical aspects.
Monitoring of the eclipsing Wolf-Rayet ULX in the Circinus galaxy
Authors: Qiu Yanli , Soria Roberto 
Published: December 2019

Abstract. We studied the eclipsing ultraluminous X-ray source CG X-1 in the Circinus galaxy, re-examining two decades of Chandra and XMM-Newton observations. The short binary period (7.21 hr) and high luminosity (LX ≈ 1040 erg s-1) suggest a Wolf-Rayet donor, close to filling its Roche lobe; this is the most luminous Wolf-Rayet X-ray binary known to-date, and a potential progenitor of a gravitational-wave merger. We phase-connect all observations, and show an intriguing dipping pattern in the X-ray lightcurve, variable from orbit to orbit. We interpret the dips as partial occultation of the X-ray emitting region by fast-moving clumps of Compton-thick gas. We suggest that the occulting clouds are fragments of the dense shell swept-up by a bow shock ahead of the compact object, as it orbits in the wind of the more massive donor.
Studying the presence of magnetic fields in a sample of high-mass X-ray binaries
Authors: Hubrig Swetlana , Kholtygin Alexander F. , Sidoli Lara , Schöller Markus , Järvinen Silva P. 
Published: December 2019

AbstractPrevious circular polarization observations obtained with the ESO FOcal Reducer low dispersion spectrograpgh at the VLT in 2007–2008 revealed the presence of a weak longitudinal magnetic field on the surface of the optical component of the X-ray binary Cyg X-1, which contains a black hole and an O9.7Iab supergiant on a 5.6 d orbit. In this contribution we report on recently acquired FORS 2 spectropolarimetric observations of Cyg X-1 along with measurements of a few additional high-mass X-ray binaries.
Local merger rates of double neutron stars
Authors: Chruslinska Martyna 
Published: December 2019

AbstractThe first detection of gravitational waves from a merging double neutron star (DNS) binary implies a much higher rate of DNS coalescences in the local Universe than typically estimated on theoretical grounds. The recent study by Chruslinska et al. (2018) shows that apart from being particularly sensitive to the common envelope treatment, DNS merger rates appear rather robust against variations of several factors probed in their study (e.g. conservativeness of the mass transfer, angular momentum loss, and natal kicks), unless extreme assumptions are made. Confrontation with the improving observational limits may allow to rule out some of the extreme models. To correctly compare model predictions with observational limits one has to account for the other factors that affect the rates. One of those factors relates to the assumed history of star formation and chemical evolution of the Universe and its impact on the final results needs to be better constrained.
Spectroscopic identication of INTEGRAL high-energy sources with VLT/ISAAC
Authors: Fortin F. , Chaty S. , Coleiro A. , Tomsick J. A. , Nitschelm C. H. R. 
Published: December 2019

AbstractINTEGRAL has been observing the γ-ray sky for 15 years and has discovered many high-energy sources of various nature. Among them, active galactic nuclei (AGN), low or high-mass X-ray binaries (LMXB and HMXB) and cataclysmic variables (CV) are rather difficult to differentiate from one another at high energies and require further optical or near-infrared observations to constrain their exact nature. Using near-infrared photometric and spectroscopic data from ESO VLT/ISAAC, we aim to reveal the nature of 14 high-energy INTEGRAL sources and improve the census of X-ray binaries. By comparing their spectral features to stellar spectra atlases, we identified 5 new CVs, 2 low or intermediate mass X-ray binaries, 2 HMXBs and 5 AGNs.
Orbital resolved spectroscopy of GX 301–2: wind diagnostics
Authors: Islam Nazma 
Published: December 2019

AbstractGX 301–2, a bright high-mass X-ray binary with an orbital period of 41.5 days, exhibits stable periodic orbital intensity modulations with a strong pre-periastron X-ray flare. Several models have been proposed to explain the accretion at different orbital phases. In Islam & Paul (2014), we presented results from an orbital resolved spectroscopic study of GX 301–2 using data from MAXI Gas Slit Camera. We have found a strong orbital dependence of the absorption column density and equivalent width of the iron emission line. A very large equivalent width of the iron line along with a small value of the column density in the orbital phase range 0.1–0.3 after the periastron passage indicates the presence of high density accretion stream. We aim to further investigate the characteristics of the accretion stream with an AstroSat observation of the system.
3D time-dependent hydrodynamical and radiative transfer modeling of Eta Carinae’s innermost fossil colliding wind structures
Authors: Madura Thomas , Gull T. R. , Clementel N. , Corcoran M. , Damineli A. , Hamaguchi K. , Hillier D. J. , Moffat A. F. J. , Richardson N. , Weigelt G. 
Published: December 2019

AbstractEta Carinae is the most massive active binary within 10,000 light-years. While famous for the largest non-terminal stellar explosion ever recorded, observations reveal a supermassive (∼120 M⊙) binary consisting of an LBV and either a WR or extreme O star in a very eccentric orbit (e=0.9) with a 5.54-year period. Dramatic changes across multiple wavelengths are routinely observed as the stars move about in their highly elliptical orbits, especially around periastron when the hot (∼40 kK) companion star delves deep into the denser and much cooler (∼15 kK) extended wind photosphere of the LBV primary. Many of these changes are due to a dynamic wind-wind collision region (WWCR) that forms between the stars, plus expanding radiation-illuminated fossil WWCRs formed one, two, and three 5.54-year orbital cycles ago. These fossil WWCRs have been spatially and spectrally resolved by the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) at multiple epochs, resulting in data cubes that spatially map Eta Carinae’s innermost WWCRs and follow temporal changes in several forbidden emission lines (e.g. [Fe iii] 4659 Å, [Fe ii] 4815 Å) across the 5.54-year cycle. We present initial results of 3D time-dependent hydrodynamical and radiative-transfer simulations of the Eta Carinae binary and its WWCRs with the goal of producing synthetic data cubes of forbidden emission lines for comparison to the available HST/STIS observations. Comparison of the theoretical models to the observations reveals important details about the binary’s orbital motion, photoionization properties, and recent (5–15year) mass loss history. Such an analysis also provides a baseline for following future changes in Eta Carinae, essential for understanding the late-stage evolution of a nearby supernova progenitor. Our modeling methods can also be adapted to a number of other colliding wind binary systems (e.g. WR 140) that are scheduled to be studied with future observatories (e.g. the James Webb Space Telescope).
Ultraluminous X-ray source populations in the Chandra Source Catalog 2.0
Authors: Kovlakas Konstantinos , Zezas Andreas , Andrews Jeff J. , Basu-Zych Antara , Fragos Tassos , Hornschemeier Ann , Lehmer Bret , Ptak Andrew 
Published: December 2019

Abstract. The nature and evolution of ultraluminous X-ray sources (ULXs) is an open problem in astrophysics. They challenge our current understanding of stellar compact objects and accretion physics. The recent discovery of pulsar ULXs further demonstrates the importance of this intriguing and rare class of objects.In order to overcome the difficulties of directly studying the optical associations of ULXs, we generally resort in statistical studies of the stellar properties of their host galaxies. We present the largest such study based on the combination of Chandra archival data with the most complete galaxy catalog of the Local Universe. Incorporating robust distances and stellar population parameters based on associated multi-wavelength information, and we explore the association of ULXs with galaxies in the (star formation rate, stellar mass, metallicity) space.We confirm the known correlation with morphology, star formation rate and stellar mass, while we find an excess of ULXs in dwarf galaxies, indicating dependence on age and metallicity.
Multifractal signatures of gravitational waves detected by LIGO
Authors: de Freitas Daniel B. , Nepomuceno Mackson M. F. , De Medeiros J. R. 
Published: December 2019

AbstractWe analyze the data from the 6 gravitational waves signals detected by LIGO through the lens of multifractal formalism using the MFDMA method, as well as shuffled and surrogate procedures. We identified two regimes of multifractality in the strain measure of the time series by examining long memory and the presence of nonlinearities. The moment used to divide the series into two parts separates these two regimes and can be interpreted as the moment of collision between the black holes. An empirical relationship between the variation in left side diversity and the chirp mass of each event was also determined.
The X-ray binary populations of M81 and M82
Authors: Sell Paul H. , Zezas Andreas , Williams Stephen J. , Andrews Jeff J. , Gazeas Kosmas , Gallagher John S. , Ptak Andrew 
Published: December 2019

AbstractWe use deep Chandra and HST data to uniquely classify the X-ray binary (XRB) populations in M81 on the basis of their donor stars and local stellar populations (into early-type main sequence, yellow giant, supergiant, low-mass, and globular cluster). First, we find that more massive, redder, and denser globular clusters are more likely to be associated with XRBs. Second, we find that the high-mass XRBs (HMXBs) overall have a steeper X-ray luminosity function (XLF) than the canonical star-forming galaxy XLF, though there is some evidence of variations in the slopes of the sub-populations. On the other hand, the XLF of the prototypical starburst M82 is described by the canonical powerlaw (αcum ∼ 0.6) down to LX ∼ 1036 erg s−1. We attribute variations in XLF slopes to different mass transfer modes (Roche-lobe overflow versus wind-fed systems).
Be stars in the X-ray binary context
Authors: Rivinius Thomas 
Published: December 2019

AbstractRapidly rotating B-type stars with gaseous mass-loss disks in Keplerian rotation are common central objects in X-Ray binaries. These disks are physically well understood in the framework of the viscous decretion disk, and their typical parameters have been established for a large number of single Be stars in the recent years. According to the current observational evidence, the Be stars and disks found in BeXRBs are well within the boundaries known from single Be stars, i.e., they are normal Be stars. New results have also been obtained on the orbital disk truncation and other tidal effects of the companion objects on the disk.
Clumpy wind accretion in Supergiant X-ray Binaries
Authors: Mellah Ileyk El , Sander Andreas A. C. , Sundqvist Jon O. , Keppens Rony 
Published: December 2019

AbstractSupergiant X-ray Binaries host a compact object, generally a neutron star, orbiting an evolved O/B star. Mass transfer proceeds through the intense radiatively-driven wind of the stellar donor, a fraction of which is captured by the gravitational field of the neutron star. The subsequent accretion process onto the neutron star is responsible for the abundant X-ray emission from those systems. They also display variations in time of the X-ray flux by a factor of a few 10, along with changes in the hardness ratios believed to be due to varying absorption along the line-of-sight. We used the most recent results on the inhomogeneities (aka clumps) in the non-stationary wind of massive hot stars to evaluate their impact on the time-variable accretion process. We ran three-dimensional simulations of the wind in the vicinity of the accretor to witness the formation of the bow shock and follow the inhomogeneous flow over several spatial orders of magnitude, down to the neutron star magnetosphere. In particular, we show that the impact of the clumps on the time-variability of the intrinsic mass accretion rate is severely damped by the crossing of the shock, compared to the purely ballistic Bondi-Hoyle-Lyttleton estimation. We also account for the variable absorption due to clumps passing by the line-of-sight and estimate the final effective variability of the mass accretion rate for different orbital separations. These results are confronted to recent analysis of Vela X-1 observations with Chandra by Grinberg et al. (2017). It shows that clumps account well for time-variability at low luminosity but can not generate, per se, the high luminosity activity observed.
ONe WD+He star systems as the progenitors of IMBPs
Authors: Wang Bo , Liu Dongdong 
Published: December 2019

AbstractPrevious theoretical studies can only explain part of the observed intermediate-mass binary pulsars (IMBPs) with short orbital periods. Note that an ONe white dwarf (WD) accreting mass from a He star may experience the accretion-induced collapse process and eventually form IMBPs, known as the ONe WD+He star scenario. By investigating the evolution of a large number of ONe WD+He star binaries, we found that the ONe WD+He star scenario can form IMBPs including pulsars with 5 – 340 ms spin periods, and the orbital periods range from 0.04 to 900 d. Compared with the observed IMBPs, this scenario can cover almost all of the IMBPs with short orbital periods. Thus, we suggest that the ONe WD+He star channel is responsible for the formation of IMBPs with short orbital periods.
X-ray binary Beta Lyrae and its donor component structure
Authors: Skulskyy M. Yu. , Vavrukh M. V. , Smerechynskyi S. V. 
Published: December 2019

AbstractWe show that the structure of magnetized accretion gas flows between the components of the Beta Lyrae system can cause a scattering gas shell that masks completely these components in soft X-ray region. Also we have calculated the inner structure of the donor that is filling a Roche lobe and is preceding a forming of the degenerate dwarf. We show that mass of the degenerate core of the donor is in region 0.3−0.5M⊙.
Massive star evolution revealed in the Mass-Luminosity plane
Authors: Higgins Erin R. , Vink Jorick S. 
Published: December 2019

AbstractMassive star evolution is dominated by key physical processes such as mass loss, convection and rotation, yet these effects are poorly constrained, even on the main sequence. We utilise a detached, eclipsing binary HD166734 as a testbed for single star evolution to calibrate new MESA stellar evolution grids. We introduce a novel method of comparing theoretical models with observations in the ‘Mass-Luminosity Plane’, as an equivalent to the HRD (see Higgins & Vink 2018). We reproduce stellar parameters and abundances of HD166734 with enhanced overshooting (αov=0.5), mass loss and rotational mixing. When comparing the constraints of our testbed to the systematic grid of models we find that a higher value of αov=0.5 (rather than αov=0.1) results in a solution which is more likely to evolve to a neutron star than a black hole, due to a lower value of the compactness parameter.