2,197 research outputs found
The RMS Survey: Far-Infrared Photometry of Young Massive Stars
Context: The Red MSX Source (RMS) survey is a multi-wavelength campaign of
follow-up observations of a colour-selected sample of candidate massive young
stellar objects (MYSOs) in the galactic plane. This survey is returning the
largest well-selected sample of MYSOs to date, while identifying other dust
contaminant sources with similar mid-infrared colours including a large number
of new ultra-compact (UC)HII regions. Aims:To measure the far-infrared (IR)
flux, which lies near the peak of the spectral energy distribution (SED) of
MYSOs and UCHII regions, so that, together with distance information, the
luminosity of these sources can be obtained. Methods:Less than 50% of RMS
sources are associated with IRAS point sources with detections at 60 micron and
100 micron, though the vast majority are visible in Spitzer MIPSGAL or IRAS
Galaxy Atlas (IGA) images. However, standard aperture photometry is not
appropriate for these data due to crowding of sources and strong spatially
variable far-IR background emission in the galactic plane. A new technique
using a 2-dimensional fit to the background in an annulus around each source is
therefore used to obtain far-IR photometry for young RMS sources.
Results:Far-IR fluxes are obtained for a total of 1113 RMS candidates
identified as young sources. Of these 734 have flux measurements using IGA 60
micron and 100 micron images and 724 using MIPSGAL 70 micron images, with 345
having measurements in both data sets.Comment: 10 pages, 10 figures, 2 Tables, accepted to A&A. A full version of
table 1 is available from the lead author or at the CDS upon publicatio
Kinematic Analysis of the 2020 Elliot Creek Landslide, British Columbia, Using Remote Sensing Data
The 2020 Elliot Creek landslide-tsunami-flood cascade originated from an 18.3 Mm3 rock slope failure in quartz diorite bedrock in a valley undergoing rapid glacial retreat. We used airborne LiDAR and optical imagery to characterize the slope and its surroundings. Using the LiDAR, we determined that two rockslides (2020 and an older undated one) occurred on this slope and shared a common basal rupture surface. We mapped two main sets of lineaments that represent structures that controlled the orientation of the lateral and rear release surfaces. Analysis of the topographic profile indicates a wedge-shaped failure block and a stepped rupture surface. Further topographic profile analysis indicates the possibility of a structurally controlled geomorphic step in the valley that corresponds with a change in the orientation of the valley. The rapid retreat of the West Grenville Glacier and the positions of the rupture surfaces suggest glacial retreat played a role in the landslides
Role of sand as substrate and dietary component for juvenile sea cucumber Holothuria scabra
The sea cucumber Holothuria scabra, or sandfish, is a commercially valuable aquaculture species; however viable intensive tank-based aquaculture techniques have not yet been developed. This study aimed to assess the role of sand as a substrate and/or dietary component in the intensive tank culture of sandfish in recirculating aquaculture systems (RAS) in South Africa. A control experiment was conducted to confirm the reported positive effect of sand as a substrate on sandfish growth and a sand-in-diet experiment was conducted to determine if the incorporation of sand into formulated diets could improve sandfish growth in bare tanks. In the control experiment, the mean growth rate of juvenile sandfish in the bare tanks was significantly lower than that of the juveniles reared in tanks with a sand substrate (-0.12 +/- 0.16 g day(-1) SE and 0.03 +/- 0.01 g day(-1) respectively; F-(1,F-2)=1.91, p0.05). Results confirmed the reported positive effect on sandfish growth when sand is provided as a substrate, however sand in diets did not promote growth in the same way, indicating that the inclusion of sand in formulated diets is unlikely to compensate for the lack of sand as a substrate. Future research should therefore aim to identify the optimum parameters of sand substrate and develop tank holding systems capable of maintaining favourable substrate conditions for intensive sandfish culture
The effect of resource quality on the growth of Holothuria scabra during aquaculture waste bioremediation
Reducing dependency on environmentally unsustainable formulated feeds, most of which include limited reserves of fishmeal as a protein source, is a priority for the aquaculture industry, particularly for intensive culture systems. One approach is to increase nitrogen reuse within the system by feeding nitrogen-rich aquaculture effluent to deposit feeders, thereby closing the aquaculture nitrogen-loop. This study, for the first time and on a laboratory-scale, has reared juveniles of the sea cucumber Holothuria scabra at high densities solely on particulate organic waste from a commercial-scale land-based abalone recirculating aquaculture system. Furthermore, growth rates and biomass yields were increased significantly by adjusting the effluent C:N from 5:1 to 20:1 by adding exogenous organic carbon sources (glucose, starch and cellulose), so fuelling accelerated heterotrophic bacterial production within the redox-stratified tank sediment. Sea cucumber juveniles reared solely on effluent had a biomass density of 711 g m−2 after four months whereas animals reared on starch-amended effluent (the best performing treatment) had a final density of 1011 g m−2. Further optimisation of this approach could increase biomass yields and pave the way for the commercial cultivation of deposit feeding animals on waste streams, thus contributing to more environmentally sustainable aquaculture. Here, the nitrogen that originated from fishmeal is not lost through the discharge of aquaculture effluent; rather, it is immobilised into single cell biomass that is up-cycled into high-value secondary biomass. We demonstrate that sea cucumbers can be produced at high density through the manipulation of the C:N ratio of aquaculture effluent
Redox Regulation, Rather than Stress-Induced Phosphorylation, of a Hog1 Mitogen-Activated Protein Kinase Modulates Its Nitrosative-Stress-Specific Outputs
Data availability. The RNA sequencing dataset is available at EBI (www.ebi.ac.uk/arrayexpress/) under accession number E-MTAB-5990. Other data that support the findings of this study are available from the corresponding author upon reasonable request. ACKNOWLEDGMENTS We thank Debbie Smith for constructing the strains JC41 and JC310, Arnab Pradhan for help with DHE control experiments, and our colleagues in the Aberdeen Fungal Group and Newcastle Yeast Group for insightful discussions. We are also grateful to Mike Gustin for his advice. We are grateful to the Centre for Genome Enabled Biology and Medicine, Aberdeen Proteomics, the Iain Fraser Cytometry Centre, the Microscopy and Histology Facility, and the qPCR facility at the University of Aberdeen for their help, advice, and support. This work was funded by the UK Biotechnology and Biological Research Council (http://www.bbsrc.ac.uk) (grants BB/K017365/1 and BB/F00513X/1 to A.J.P.B. and grant BB/K016393/1 to J.Q.). This work was also supported by the European Research Council (http://erc.europa.eu/) (STRIFE advanced grant C-2009-AdG-249793 to A.J.P.B.), the UK Medical Research Council (http://www.mrc.ac.uk) (grant MR/M026663/1 to A.J.P.B. and grant MR/M000923/1 to P.S.S.), the Wellcome Trust (https://wellcome.ac.uk) (grant 097377 to A.J.P.B. and J.Q.), the MRC Centre for Medical Mycology and the University of Aberdeen (grant MR/M026663/1 to A.J.P.B.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
The RMS Survey: The Bolometric Fluxes and Luminosity Distributions of Young Massive Stars
Context: The Red MSX Source (RMS) survey is returning a large sample of
massive young stellar objects (MYSOs) and ultra-compact (UC) \HII{} regions
using follow-up observations of colour-selected candidates from the MSX point
source catalogue. Aims: To obtain the bolometric fluxes and, using kinematic
distance information, the luminosities for young RMS sources with far-infrared
fluxes. Methods: We use a model spectral energy distribution (SED) fitter to
obtain the bolometric flux for our sources, given flux data from our work and
the literature. The inputs to the model fitter were optimised by a series of
investigations designed to reveal the effect varying these inputs had on the
resulting bolometric flux. Kinematic distances derived from molecular line
observations were then used to calculate the luminosity of each source.
Results: Bolometric fluxes are obtained for 1173 young RMS sources, of which
1069 have uniquely constrained kinematic distances and good SED fits. A
comparison of the bolometric fluxes obtained using SED fitting with trapezium
rule integration and two component greybody fits was also undertaken, and
showed that both produce considerable scatter compared to the method used here.
Conclusions: The bolometric flux results allowed us to obtain the luminosity
distributions of YSOs and UC\HII{} regions in the RMS sample, which we find to
be different. We also find that there are few MYSOs with L
10\lsol{}, despite finding many MYSOs with 10\lsol{} L
10\lsol{}.Comment: 12 pages, 12 figures, 3 tables, accepted to A&A. The full versions of
tables 1 and 2 will be available via the CDS upon publicatio
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Confident, fearful and hopeless cooks: Findings from the development of a food-skills initiative
One of the many barriers to a healthier diet in low-income communities is a presumed lack of practical food skills. This article reports findings from exploratory qualitative research conducted with potential participants in a cooking skills intervention, in low income communities in Scotland. The research found widely varying levels of skill and confidence regarding cooking, supported the need for a community-based intervention approach, and demonstrated the importance of consumer research to inform the content of interventions. Challenges the view that low income communities lack skills, suggesting that food skills should be defined more broadly than “cooking from scratch”. Other barriers to healthy eating, such as poverty, food access and taste preferences, remain important
Enhanced smoking cessation support for newly abstinent smokers discharged from hospital (The Hospital to Home trial): A randomised controlled trial
Background and aimsThe United Kingdom's National Institute for Health and Care Excellence guidance (NICE PH48) recommends that pharmacotherapy combined with behavioural support be provided for all smokers admitted to hospital; however, relapse to smoking after discharge remains common. This study aimed to assess the effect of adding home support for newly?abstinent smokers to conventional NICE?recommended support in smokers discharged from hospital.Designindividually?randomised parallel group trial.SettingOne UK acute hospital.Participants404 smokers aged >18 admitted to acute medical wards between June 2016 and July 2017 were randomised in equal numbers to each treatment group.Interventions and comparatorsThe intervention provided 12 weeks of at?home cessation support which included help in maintaining a smoke?free home, help in accessing and using medication, further behavioural support and personalised feedback on home air quality. The comparator was NICE PH48 care as usual.MeasuresThe primary outcome was self?reported continuous abstinence from smoking validated by an exhaled carbon monoxide level ?6ppm four?weeks after discharge from hospital.FindingsIn an intention?to?treat analysis at the four?week primary endpoint, 38 participants (18.8%) in the usual care group and 43 (21.3%) in the intervention group reported continuous abstinence from smoking (odds ratio 1.17, 95% confidence interval 0.72 to 1.90, Bayes factor 0.33). There were no significant differences in any secondary outcomes, including self?reported cessation at 3 months, having a smoke?free home, or number of cigarettes smoked per day in those who did not quit.ConclusionsProvision of a home visit and continued support to prevent relapse to smoking after hospital discharge did not appear to increase subsequent abstinence rate above usual care in accordance with UK guidance from the National Institute of Health and Care Excellence
Redox stratification drives enhanced growth in a deposit-feeding invertebrate: Implications for aquaculture bioremediation
Effective and affordable treatment of waste solids is a key sustainability challenge for the aquaculture industry. Here, we investigated the potential for a deposit-feeding sea cucumber, Holothuria scabra, to provide a remediation service whilst concurrently yielding a high-value secondary product in a land-based recirculating aquaculture system (RAS). The effect of sediment depth, particle size and redox regime were examined in relation to changes in the behaviour, growth and biochemical composition of juvenile sea cucumbers cultured for 81 d in manipulated sediment systems, describing either fully oxic or stratified (oxic-anoxic) redox regimes. The redox regime was the principal factor affecting growth, biochemical composition and behaviour, while substrate depth and particle size did not significantly affect growth rate or biomass production. Animals cultured under fully oxic conditions exhibited negative growth and had higher lipid and carbohydrate contents, potentially due to compensatory feeding in response to higher micro - phyto benthic production. In contrast, animals in the stratified treatments spent more time feeding, generated faster growth and produced significantly higher biomass yields (626.89 ± 35.44 g m-2 versus 449.22 ± 14.24 g m-2; mean ± SE). Further, unlike in oxic treatments, growth in the stratified treatments did not reach maximum biomass carrying capacity, indicating that stratified sediment is more suitable for culturing sea cucumbers. However, the stratified sediments may exhibit reduced bioremediation ability relative to the oxic sediment, signifying a trade-off between remediation efficiency and exploitable biomass yiel
Using systems thinking and open innovation to strengthen aquaculture policy for the United Nations Sustainable Development Goals
In a world of nine billion people and a widening income gap between the rich and poor, it is time to rethink how aquaculture can strengthen its contribution to the second UN Sustainable Development Goal (SDG) of zero hunger in our generation. The disparity in the level of sustainable aquaculture development at present, between and within countries, especially regarding human access to farmed aquatic food remains highly variable across the globe. This paper offers a fresh look at the opportunities from using systems thinking and new open innovation measuring tools to grow sustainable aquaculture. Political will in many nations is the main constraint to aquaculture in realising its potential as an: accessible source of micronutrients and nutritious protein; aid to meeting conservation goals; economic prosperity generator where benefits extend to locals and provider of indirect social benefits such as access to education and well‐being, among others. Resources to enable strong partnerships (SDG 17) between academia, civic society, government and industry should be prioritised by governments to build a sustainable aquatic food system, accessible to all, forever
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