1,782 research outputs found

    Cats, comics and Knausgård : promoting student reading at a UK academic library with a leisure reading collection

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    This case study describes the creation of a leisure reading collection in the Clifford Whitworth library at the University of Salford. It briefly surveys existing literature on leisure reading collections and looks at the growing interest among UK academic libraries in recreational reading. It considers the reasons for promoting reading as a leisure activity to students and describes the processes of selecting, purchasing and marketing the collection at Salford. It also considers possible future developments for the collection and the evaluation of the library’s attempts to encourage a culture of reading amongst Salford students. The positive response to the collection suggests the development of leisure reading is a worthwhile activity for academic libraries to focus on and the study contains useful information for others who are interested in creating a similar collection

    Evolution of an eruptive flare loop system

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    <p><b>Context:</b> Flares, eruptive prominences and coronal mass ejections are phenomena where magnetic reconnection plays an important role. However, the location and the rate of the reconnection, as well as the mechanisms of particle interaction with ambient and chromospheric plasma are still unclear.</p> <p><b>Aims:</b> In order to contribute to the comprehension of the above mentioned processes we studied the evolution of the eruptive flare loop system in an active region where a flare, a prominence eruption and a CME occurred on August 24, 2002.</p> <p><b>Methods:</b> We measured the rate of expansion of the flare loop arcade using TRACE 195 Å images and determined the rising velocity and the evolution of the low and high energy hard X-ray sources using RHESSI data. We also fitted HXR spectra and considered the radio emission at 17 and 34 GHZ.</p> <p><b>Results:</b> We observed that the top of the eruptive flare loop system initially rises with a linear behavior and then, after 120 mn from the start of the event registered by GOES at 1–8 Å, it slows down. We also observed that the heating source (low energy X-ray) rises faster than the top of the loops at 195 Å and that the high energy X-ray emission (30–40 keV) changes in time, changing from footpoint emission at the very onset of the flare to being coincident during the flare peak with the whole flare loop arcade.</p> <p><b>Conclusions:</b> The evolution of the loop system and of the X-ray sources allowed us to interpret this event in the framework of the Lin & Forbes model (2000), where the absolute rate of reconnection decreases when the current sheet is located at an altitude where the Alfvén speed decreases with height. We estimated that the lower limit for the altitude of the current sheet is km. Moreover, we interpreted the unusual variation of the high energy HXR emission as a manifestation of the non thermal coronal thick-target process which appears during the flare in a manner consistent with the inferred increase in coronal column density.</p&gt

    Eurasian Arctic greening reveals teleconnections and the potential for novel ecosystems

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    Arctic warming has been linked to observed increases in tundra shrub cover and growth in recent decades on the basis of significant relationships between deciduous shrub growth/biomass and temperature. These vegetation trends have been linked to Arctic sea ice decline and thus to the sea ice/albedo feedback known as Arctic amplification. However, the interactions between climate, sea ice and tundra vegetation remain poorly understood. Here we reveal a 50- year growth response over a >100,000 km2 area to a rise in summer temperature for alder (Alnus) and willow (Salix), the most abundant shrub genera respectively at and north of the continental treeline. We demonstrate that whereas plant productivity is related to sea ice in late spring, the growing season peak responds to persistent synoptic-scale air masses over West Siberia associated with Fennoscandian weather systems through the Rossby wave train. Substrate is important for biomass accumulation, yet a strong correlation between growth and temperature encompasses all observed soil types. Vegetation is especially responsive to temperature in early summer. These results have significant implications for modelling present and future Low Arctic vegetation responses to climate change, and emphasize the potential for structurally novel ecosystems to emerge fromwithin the tundra zone.Vertaisarviointia edeltävä käsikirjoitu

    Integrated knowledge translation strategies that enhance the lives of persons with dementia and their family caregivers

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    Purpose: To understand the lived experience of persons with dementia and their family caregivers who receive home care in northern Alberta, Canada, and to reveal how integrated knowledge translation (iKT) strategies influence the uptake of best available dementia care evidence over time. Sample: Three persons living with dementia and thirteen family caregivers were interviewed at the beginning of the study, nine months after implementation of the knowledge broker (KB), and six months after termination of the KB role (total interviews = 41). Method: The PARiHS framework guided our longitudinal case study that included two rural home care centres. A qualitative interpretive descriptive approach was used. A KB was hired for 12 months to facilitate the development of different iKT strategies with staff. Site A developed two strategies: 1) a planning meeting to discuss local needs and suggestions for improving access to dementia care information and community supports; and 2) the development of an information package. Site B focused on working through modules of the U-First program that entailed dementia education and training for the home care providers (HCPs). They then used the U-First wheels with clients during their home visits. Findings: Persons living with dementia spoke of both positive and negative aspects of their dementia journey and how they attempted to manage their lives. Family caregivers struggled to find the best approaches and supports to use to enable their family member with dementia to remain at home for as long as possible. iKT strategies such as a KB, the information resource package developed by the HCPs, use of the U-First modules and wheels, and a support group were examples of effective iKT. Conclusion: iKT strategies and projects increased access to dementia care information and supports. These assisted caregivers to better care for their family member for longer periods at home. Keywords: Persons living with dementia, family caregivers, integrated knowledge translation strategies, rural, and home car

    Towards the bioequivalence of pressurised metered dose inhalers 2. Aerodynamically equivalent particles (with and without glycerol) exhibit different biopharmaceutical profiles in vitro

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    Two solution-based pressurised metered dose inhaler (pMDI) formulations were prepared such that they delivered aerosols with identical mass median aerodynamic diameters, but contained either beclomethasone dipropionate (BDP) alone (glycerol-free formulation) or BDP and glycerol in a 1:1 mass ratio (glycerol-containing formulation). The two formulations were deposited onto Calu-3 respiratory epithelial cell layers cultured at an air interface. Equivalent drug mass (∼1000 ng or ∼2000 ng of the formulation) or equivalent particle number (1000 ng of BDP in the glycerol-containing versus 2000 ng of BDP in the glycerol-free formulation) were deposited as aerosolised particles on the air interfaced surface of the cell layers. The transfer rate of BDP across the cell layer after deposition of the glycerol-free particles was proportional to the mass deposited. In comparison, the transfer of BDP from the glycerol-containing formulation was independent of the mass deposited, suggesting that the release of BDP is modified in the presence of glycerol. The rate of BDP transfer (and the extent of metabolism) over 2 h was faster when delivered in glycerol-free particles, 465.01 ng ± 95.12 ng of the total drug (20.99 ± 4.29%; BDP plus active metabolite) transported across the cell layer, compared to 116.17 ng ± 3.07 ng (6.07 ± 0.16%) when the equivalent mass of BDP was deposited in glycerol-containing particles. These observations suggest that the presence of glycerol in the maturated aerosol particles may influence the disposition of BDP in the lungs.© 2013 Elsevier B.V. All rights reserved

    The SLUGGS survey: globular clusters and the dark matter content of early-type galaxies

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    A strong correlation exists between the total mass of a globular cluster (GC) system and the virial halo mass of the host galaxy. However, the total halo mass in this correlation is a statistical measure conducted on spatial scales that are some 10 times that of a typical GC system. Here we investigate the connection between GC systems and galaxy's dark matter on comparable spatial scales, using dynamical masses measured on a galaxy-by-galaxy basis. Our sample consists of 17 well-studied massive (~10 x 11 M☉) early-type galaxies from the SLUGGS survey. We find the strongest correlation to be that of the blue (metal-poor) GC subpopulation and the dark matter content. This correlation implies that the dark matter mass of a galaxy can be estimated to within a factor of 2 from careful imaging of its GC system. The ratio of the GC system mass to that of the enclosed dark matter is nearly constant. We also find a strong correlation between the fraction of blue GCs and the fraction of enclosed dark matter, so that a typical galaxy with a blue GC fraction of 60 per cent has a dark matter fraction of 86 per cent over similar spatial scales. Both halo growth and removal (via tidal stripping) may play some role in shaping this trend. In the context of the two-phase model for galaxy formation, we find galaxies with the highest fractions of accreted stars to have higher dark matter fractions for a given fraction of blue GCs

    Explaining the mysterious age gap of globular clusters in the Large Magellanic Cloud

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    The Large Magellanic Cloud (LMC) has a unique cluster formation history in that nearly all of its globular clusters were formed either ∼\sim 13 Gyr ago or less than ∼\sim 3 Gyr ago. It is not clear what physical mechanism is responsible for the most recent cluster formation episode and thus the mysterious age gap between the LMC clusters. We first present results of gas dynamical N-body simulations of the evolution of the LMC in the context of its Galactic orbit and interactions with the SMC, paying special attention to the effect of tidal forces. We find that the first close encounter between the LMC and the Small Magellanic Cloud (SMC) about 4 Gyr ago was the beginning of a period of strong tidal interaction which likely induced dramatic gas cloud collisions, leading to an enhancement of the formation of globular clusters which has been sustained by strong tidal interactions to the present day. The tidal interaction results in the formation of a barred, elliptical, thick disk in the LMC. The model also predicts the presence of a large, diffuse stellar stream circling the Galaxy, which originated from the LMC.Comment: 14 pages, 4 figures (f2.copy.jpg for high-res color figure), accepted by ApJ

    The SLUGGS survey: the assembly histories of individual early-type galaxies

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    Early-type (E and S0) galaxies may have assembled via a variety of different evolutionary pathways. Here, we investigate these pathways by comparing the stellar kinematic properties of 24 early-type galaxies from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey with the hydrodynamical simulations of Naab et al. In particular, we use the kinematics of starlight up to 4 effective radii (Re) as diagnostics of galaxy inner and outer regions, and assign each galaxy to one of six Naab et al. assembly classes. The majority of our galaxies (14/24) have kinematic characteristics that indicate an assembly history dominated by gradual gas dissipation and accretion of many gas-rich minor mergers. Three galaxies, all S0s, indicate that they have experienced gas-rich major mergers in their more recent past. One additional elliptical galaxy is tentatively associated with a gas-rich merger which results in a remnant galaxy with low angular momentum. Pathways dominated by gas-poor (major or minor) mergers dominate the mass growth of six galaxies. Most SLUGGS galaxies appear to have grown in mass (and size) via the accretion of stars and gas from minor mergers, with late major mergers playing a much smaller role. We find that the fraction of accreted stars correlates with the stellar mean age and metallicity gradient, but not with the slope of the total mass density profile. We briefly mention future observational and modelling approaches that will enhance our ability to accurately reconstruct the assembly histories of individual present-day galaxies
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