106 research outputs found
The Spatial and Emission Properties of the Large [O III] Emission Nebula Near M31
Drechsler et al. (2023) reported the unexpected discovery of a 1.5 degree
long [O III] emission nebula 1.2 degrees southeast of the M31 nucleus. Here we
present additional images of this large emission structure, called SDSO, along
with radial velocity and flux measurements from low-dispersion spectra.
Independent sets of [O III] images show SDSO to be composed of broad streaks of
diffuse emission aligned NE-SW. Deep H images reveal no strong
coincident emission suggesting a high [O III]/H ratio. We also find no
other [O III] emission nebulosity as bright as SDSO within several degrees of
M31 and no filamentary H emission connected to SDSO. Optical spectra
taken along the arc's northern limb reveal [O III] 4959,5007
emissions matching the location and extent seen in our [O III] images. The
heliocentric velocity of this [O III] nebulosity is km s
with a peak surface brightness of erg s
cm arcsec (0.55 Rayleigh). We discuss SDSO as a possible
unrecognized supernova remnant, a large and unusually nearby planetary nebula,
a stellar bow shock nebula, or an interaction of M31's outer halo gas with
high-velocity circumgalactic gas. We conclude that galactic origins for SDSO
are unlikely and favor instead an extragalactic M31 halo--circumgalactic cloud
interaction scenario, despite the nebula's low radial velocity. We then
describe new observations that may help resolve the true nature and origin of
this large nebulosity so close to M31 in the sky.Comment: 21 pages, 12 figure
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The impact generated by public and charity-funded research in the UK: A systematic literature review
Objective: To identify, synthesize and critically assess the empirical evidence of the impact generated by public and charity funded health research in the United Kingdom.
Methods: We conducted a systematic literature review of the empirical evidence published in English in peer-reviewed journals between 2006 and 2017. Studies meeting the inclusion criteria were selected and their findings were analysed using the Payback Framework into five main categories: knowledge, benefits to future research and research use, benefits from informing policy and product development, health and health sector benefits and broader economic benefits. We assessed the studies for risk of selection, reporting and funding bias.
Results: Thirteen studies met the inclusion criteria. The majority of the studies (10 out of 13) assessed impact at multiple domains including the main 5 key themes of the Payback Framework. All of them showed a positive impact of funded research on outcomes. Of those studies, one presented low risk of bias (8%), 6 studies were classified as presenting moderate risk of bias (46%) and 6 studies presented high risk of bias (46%).
Conclusions: Empirical evidence on the impact of public and charity funded research is still limited and subject to funding and selection bias. More work is needed to establish the causal effects of funded research on academic outcomes, policy, practice and the broader economy
The Role of Practice Research Networks (PRN) in the Development and Implementation of Evidence: The Northern Improving Access to Psychological Therapies PRN Case Study
Practice research networks (PRNs) can support the implementation of evidence based practice in routine services and generate practice based evidence. This paper describes the structure, processes and learning from a new PRN in the Improving Access to Psychological Therapies programme in England, in relation to an implementation framework and using one study as a case example. Challenges related to: ethics and governance processes; communications with multiple stakeholders; competing time pressures and linking outcome data. Enablers included: early tangible outputs and impact; a collaborative approach; engaging with local research leads; clarity of processes; effective dissemination; and committed leadership
Burial Depth and Stolon Internode Length Independently Affect Survival of Small Clonal Fragments
Disturbance can fragment plant clones into different sizes and unstabilize soils to different degrees, so that clonal fragments of different sizes can be buried in soils at different depths. As a short-term storage organ, solon internode may help fragmented clones of stoloniferous plants to withstand deeper burial in soils. We address (1) whether burial in soils decreases survival and growth of small clonal fragments, and (2) whether increasing internode length increases survival and growth of small fragments under burial. We conducted an experiment with the stoloniferous, invasive herb Alternanthera philoxeroides, in which single-node fragments with stolon internode of 0, 2, 4 and 8 cm were buried in soils at 0, 2, 4 and 8 cm depth, respectively. Increasing burial depth significantly reduced survival of the A. philoxeroides plants and increased root to shoot ratio and total stolon length, but did not change growth measures. Increasing internode length significantly increased survival and growth measures, but there was no interaction effect with burial depth on any traits measured. These results indicate that reserves stored in stolon internodes can contribute to the fitness of the A. philoxeroides plants subject to disturbance. Although burial reduced the regeneration capacity of the A. philoxeroides plants, the species may maintain the fitness by changing biomass allocation and stolon length once it survived the burial. Such responses may play an important role for A. philoxeroides in establishment and invasiveness in frequently disturbed habitats
Une nouvelle station du Paléolithique moyen au Sud du village de Mont-les-Etrelles (Haute-Saône)
Claudel J., Sainty J. Une nouvelle station du Paléolithique moyen au Sud du village de Mont-les-Etrelles (Haute-Saône). In: Bulletin de la Société préhistorique française. Comptes rendus des séances mensuelles, tome 67, n°3, 1970. pp. 68-70
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