350 research outputs found
The Chromospheric Activity, Age, Metallicity, and Space Motions of 36 Wide Binaries
We present the chromospheric activity (CA) levels, metallicities, and full space motions for 41 F, G, K, and M dwarf stars in 36 wide binary systems. Thirty-one of the binaries contain a white dwarf (WD) component. In such binaries, the total age can be estimated by adding the cooling age of the WD to an estimate of the progenitor’s main-sequence lifetime. To better understand how CA correlates to stellar age, 14 cluster member stars were also observed. Our observations demonstrate for the first time that, in general, CA decays with age from 50 Myr to at least 8 Gyr for stars with 1.0 \u3c V − I \u3c 2.4. However, little change occurs in the CA level for stars with V − I \u3c 1.0 between 1 Gyr and 5 Gyr, consistent with the results of Pace et al. Our sample also exhibits a negative correlation between the stellar age and metallicity, a positive correlation between the stellar age and W space velocity component, and the W velocity dispersion increases with age. Finally, the population membership of these wide binaries is examined based upon their U, V, W kinematics, metallicity, and CA. We conclude that wide binaries are similar to field and cluster stars in these respects. More importantly, they span a much more continuous range in age and metallicity than is afforded by nearby clusters
The Chromospheric Activity, Age, Metallicty and Space Motions of 36 Wide Binaries
We present the chromospheric activity (CA) levels, metallicities and full
space motions for 41 F, G, K and M dwarf stars in 36 wide binary systems.
Thirty-one of the binaries, contain a white dwarf component. In such binaries
the total age can be estimated by adding the cooling age of the white dwarf to
an estimate of the progenitor's main sequence lifetime. To better understand
how CA correlates to stellar age, 14 cluster member stars were also observed.
Our observations demonstrate for the first time that in general CA decays with
age from 50 Myr to at least 8 Gyr for stars with 1.0 < V-I < 2.4. However,
little change occurs in CA level for stars with V-I < 1.0 between 1 Gyr and 5
Gyr, consistent with the results of Pace et al. (2009). Our sample also
exhibits a negative correlation between stellar age and metallicity, a positive
correlation between stellar age and W space velocity component and the W
velocity dispersion increases with age. Finally, the population membership of
these wide binaries is examined based upon their U, V, W kinematics,
metallicity and CA. We conclude that wide binaries are similar to field and
cluster stars in these respects. More importantly, they span a much more
continuous range in age and metallicity than is afforded by nearby clusters.Comment: 28 pages, 6 figures, accepted for publication in A
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Exploring the literacy related behaviours and feelings of pupils eligible for free school meals in relation to their use of, and access to, school libraries
Although it has been argued that school libraries are important for supporting the reading engagement of pupils who receive free school meals, to date there has been little analysis of the extent to which use of school library spaces is related to these pupils' reading behaviors. We analyzed data from 6,264 UK children and young people entitled to FSM who completed the 2019 National Literacy Trust Annual Literacy Survey, to understand the extent to which these pupils' engagement with reading and writing is related to access to or use of their school library. We found their enjoyment of both reading and writing, their confidence in their own abilities, and the frequency with which they read or wrote for pleasure outside of school was significantly higher for those pupils eligible for FSM who used their school libraries relative to both those who did not, and those who had no school library. Consistent with this, children eligible for FSM who used their school library engaged with a greater diversity of reading material and writing than those who were not school library users. We argue that school library provision appears to be a significant resource in supporting low income children's engagement with self-motivated literacy practices
Novel insights into host-fungal pathogen interactions derived from live-cell imaging
Acknowledgments The authors acknowledge funding from the Wellcome Trust (080088, 086827, 075470 and 099215) including a Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377 and FP7-2007–2013 grant agreement HEALTH-F2-2010-260338–ALLFUN to NARG.Peer reviewedPublisher PD
Patterns of Intergenerational Transfers in Southeast Asia
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73942/1/j.1741-3737.2002.00627.x.pd
Cell walls of the dimorphic fungal pathogens Sporothrix schenckii and Sporothrix brasiliensis exhibit bilaminate structures and sloughing of extensive and intact layers
This work was supported by the Fundação Carlos Chagas de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), grants E-26/202.974/2015 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), grants 229755/2013-5, Brazil. LMLB is a senior research fellow of CNPq and Faperj. NG acknowledged support from the Wellcome Trust (Trust (097377, 101873, 200208) and MRC Centre for Medical Mycology (MR/N006364/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
How residents and interns utilise and perceive the personal digital assistant and UpToDate
<p>Abstract</p> <p>Background</p> <p>In this era of evidence-based medicine, doctors are increasingly using information technology to acquire medical knowledge. This study evaluates how residents and interns utilise and perceive the personal digital assistant (PDA) and the online resource UpToDate.</p> <p>Methods</p> <p>This is a questionnaire survey of all residents and interns in a tertiary teaching hospital.</p> <p>Results</p> <p>Out of 168 doctors, 134 (79.8%) responded to the questionnaire. Only 54 doctors (40.3%) owned a PDA. Although these owners perceived that the PDA was most useful for providing drug information, followed by medical references, scheduling and medical calculators, the majority of them did not actually have medical software applications downloaded on their PDAs. The greatest concerns highlighted for the PDA were the fear of loss and breakage, and the preference for working with desktop computers and paper. Meanwhile, only 76 doctors (56.7%) used UpToDate, even though the hospital had an institutional subscription for it. Although 93.4% of these users would recommend UpToDate to a colleague, only 57.9% stated that the use of UpToDate had led to a change in their management of patients.</p> <p>Conclusion</p> <p>Although UpToDate and various PDA software applications were deemed useful by some of the residents and interns in our study, both digital tools were under-utilised. More should be done to facilitate the use of medical software applications on PDAs, to promote awareness of tools for evidence-based medicine such as UpToDate, and to facilitate the application of evidence-based medicine in daily clinical practice.</p
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