4,226 research outputs found

    Circulation near the Newfoundland Ridge

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    Mesoscale eddies (25 to 150 km diameter) are observed to occur along the crest of the Newfoundland Ridge and have water properties that suggest an origin near the Tail of the Bank. The eddies appear to be important features of the circulation over the Ridge...

    High resolution sub-millimetre mapping of starburst galaxies: Comparison with CO emission

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    Researchers present first results from a program of submillimeter continuum mapping of starburst galaxies, and comparison of their dust and CO emission. This project was prompted by surprising results from the first target, the nearby starburst M82, which shows in the dust continuum a morphology quite unlike that of its CO emission, in contrast to what might be expected if both CO and dust are accurately tracing the molecular hydrogen. Possible explanations for this striking difference are discussed. In the light of these results, the program has been extended to include sub-mm mapping of the nearby, vigorously star forming spirals, M83 and Maffei 2. The latter were also observed extensively in CO, in order to study excitation conditions in its central regions. The James Clerk Maxwell Telescope was used in these studies

    Discovery of a High Proper Motion L Dwarf Binary: 2MASS J15200224-4422419AB

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    We report the discovery of the wide L1.5+L4.5 binary 2MASS J15200224-4422419AB, identified during spectroscopic followup of high proper motion sources selected from the Two Micron All Sky Survey. This source was independently identified by Kendall et al. in the SuperCOSMOS Sky Survey. Resolved JHK photometry and low resolution near-infrared spectroscopy demonstrate that this system is composed of two well-separated (1"174+/-0"016) L dwarfs. Component classifications are derived using both spectral ratios and comparison to near-infrared spectra of previously classified field L dwarfs. Physical association for the pair is deduced from the large (mu = 0"73+/-0"03 /yr) common proper motion of the components and their similar spectrophotometric distances (19+/-2 pc). The projected separation of the binary, 22+/-2 AU, is consistent with maximum separation/total system mass trends for very low mass binaries. The 2MASS J1520-4422 system exhibits both large tangential (66+/-7 km/s) and radial velocities (-70+/-18 km/s), and its motion in the local standard of rest suggests that it is an old member of the Galactic disk population. This system joins a growing list of well-separated (>0"5), very low mass binaries, and is an excellent target for resolved optical spectroscopy to constrain its age as well as trace activity/rotation trends near the hydrogen-burning limit.Comment: 35 pages, 8 figures; accepted for publication to ApJ; see also Kendall et al. astro-ph/060939

    Examining the use of telehealth in community nursing: identifying the factors affecting frontline staff acceptance and telehealth adoption

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    Aims: To examine frontline staff acceptance of telehealth and identify barriers to and enablers of successful adoption of remote monitoring for patients with Chronic Obstructive Pulmonary Disease and Chronic Heart Failure. Background: The use of telehealth in the UK has not developed at the pace and scale anticipated by policy. Many existing studies report frontline staff acceptance as a key barrier, however data are limited and there is little evidence of the adoption of telehealth in routine practice. Design: Case studies of four community health services in England that use telehealth to monitor patients with Chronic Obstructive Pulmonary Disease and Chronic Heart Failure. Methods: Thematic analysis of qualitative interviews with 84 nursing and other frontline staff; and 21 managers and key stakeholders; data collected May 2012-June 2013. Findings: Staff attitudes ranged from resistance to enthusiasm, with varied opinions about the motives for investing in telehealth and the potential impact on nursing roles. Having reliable and flexible technology and dedicated resources for telehealth work were identified as essential in helping to overcome early barriers to acceptance, along with appropriate staff training and a partnership approach to implementation. Early successes were also important, encouraging staff to use telehealth and facilitating clinical learning and increased adoption. Conclusions: The mainstreaming of telehealth hinges on clinical 'buy-in'. Where barriers to successful implementation exist, clinicians can lose faith in using technology to perform tasks traditionally delivered in person. Addressing barriers is therefore crucial if clinicians are to adopt telehealth into routine practice

    Recruiting hard to reach populations to studies: breaking the silence: an example from a study that recruited people with dementia

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    Objective To share the challenges of recruiting people with dementia to studies, using experiences from one recently completed trial as an exemplar. Background Research publications always cite participant numbers but the effort expended to achieve the sample size is rarely reported, even when the study involved recruiting a hard to reach population. A multisite study of a psychosocial intervention for people with dementia illustrates the challenges. This study recruited 468 ‘dyads’ (a person with dementia and a family carer together) from 15 sites but the time taken to achieve this was longer than originally estimated. This led to a study extension and the need for additional sites. Recruitment data revealed that certain sites were more successful than others, but why? Can the knowledge gained be used to inform other studies? Methods Secondary analysis of routinely collected recruitment data from three purposefully selected sites was examined to understand the strategies used and identify successful approaches. Findings At all three sites, the pool of potential recruits funnelled to a few participants. It took two sites 18 months longer than the third to achieve recruitment numbers despite additional efforts. Explanations given by potential participants for declining to take part included ill health, reporting they were ‘managing’, time constraints, adjusting to a diagnosis of dementia and burden of study procedures. Conclusions Successful recruitment of people with dementia to studies, as one example of a hard to reach group, requires multiple strategies and close working between researchers and clinical services. It requires a detailed understanding of the needs and perspectives of the specific population and knowledge about how individuals can be supported to participate in research. Experiences of recruitment should be disseminated so that knowledge generated can be used to inform the planning and implementation of future research studies

    Evidence of two viscous relaxation processes in the collective dynamics of liquid lithium

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    New inelastic X-ray scattering experiments have been performed on liquid lithium in a wide wavevector range. With respect to the previous measurements, the instrumental resolution, improved up to 1.5 meV, allows to accurately investigate the dynamical processes determining the observed shape of the the dynamic structure factor, S(Q,ω)S(Q,\omega). A detailed analysis of the lineshapes shows the co-existence of relaxation processes with both a slow and a fast characteristic timescales, and therefore that pictures of the relaxation mechanisms based on a simple viscoelastic model must be abandoned.Comment: 5 pages, 4 .PS figure

    A 'Common Practice' Approach to Attract and Retain Engineering Students

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    Solidity of viscous liquids. V. Long-wavelength dominance of the dynamics

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    This paper is the fifth in a series exploring the physical consequences of the solidity of glass-forming liquids. Paper IV proposed a model where the density field is described by a time-dependent Ginzburg-Landau equation of the nonconserved type with rates in kk space of the form Γ0+Dk2\Gamma_0+Dk^2. The model assumes that DΓ0a2D\gg\Gamma_0a^2 where aa is the average intermolecular distance; this inequality expresses a long-wavelength dominance of the dynamics which implies that the Hamiltonian (free energy) to a good approximation may be taken to be ultralocal. In the present paper we argue that this is the simplest model consistent with the following three experimental facts: 1) Viscous liquids approaching the glass transition do not develop long-range order; 2) The glass has lower compressibility than the liquid; 3) The alpha process involves several decades of relaxation times shorter than the mean relaxation time. The paper proceeds to list six further experimental facts characterizing equilibrium viscous liquid dynamics and shows that these are readily understood in terms of the model; some are direct consequences, others are quite natural when viewed in light of the model

    Efficient Replication of Over 180 Genetic Associations with Self-Reported Medical Data

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    While the cost and speed of generating genomic data have come down dramatically in recent years, the slow pace of collecting medical data for large cohorts continues to hamper genetic research. Here we evaluate a novel online framework for amassing large amounts of medical information in a recontactable cohort by assessing our ability to replicate genetic associations using these data. Using web-based questionnaires, we gathered self-reported data on 50 medical phenotypes from a generally unselected cohort of over 20,000 genotyped individuals. Of a list of genetic associations curated by NHGRI, we successfully replicated about 75% of the associations that we expected to (based on the number of cases in our cohort and reported odds ratios, and excluding a set of associations with contradictory published evidence). Altogether we replicated over 180 previously reported associations, including many for type 2 diabetes, prostate cancer, cholesterol levels, and multiple sclerosis. We found significant variation across categories of conditions in the percentage of expected associations that we were able to replicate, which may reflect systematic inflation of the effects in some initial reports, or differences across diseases in the likelihood of misdiagnosis or misreport. We also demonstrated that we could improve replication success by taking advantage of our recontactable cohort, offering more in-depth questions to refine self-reported diagnoses. Our data suggests that online collection of self-reported data in a recontactable cohort may be a viable method for both broad and deep phenotyping in large populations
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