1,493 research outputs found
NOC Liverpool Unit 117 Glider deployment report for the DEFRA MAREMAP Project, April - May 2012 deployment
This document summarises the extended deployment of a 200 metre depth rated Slocum Electric glider by the National Oceanography Centre, Liverpool, UK from the 2nd April to 17th May 2012. The deployment was aimed as a pilot study for the use of gliders by environment agencies to monitor marine conservation zones. Lithium expendable batteries were used inside the glider to provide an extended endurance. The glider had a series of science sensors installed to measure physical oceanographic and biological parameters that included water quality and algal activity. The glider was deployed from the Liverpool Bay and successfully navigated to the intended survey area that was more than 100km from the initial deployment location. Extensive independent scientific measurements were taken during the glider deployment and subsequent operation. These measurements were used for glider sensor calibration and the monitoring of any sensor drift. Avoidance and managing of the many hazards typical in the survey area such as shipping, strong tidal currents and fixed platforms were required during the deployment. This was achieved by remotely piloting the glider with using a satellite based communications link. After a deployment of just over six weeks a suspected glider entanglement close to the seabed occurred during a routine survey dive and attempted subsequent climb underwater. This compromised the glider operation during its return to shallower, more sheltered coastal waters for an intended recovery. An emergency recovery was then required that used a small charted deep sea fishing vessel. This document provides an overview of the deployment requirements, the glider operations and the recovered glider initial evaluation. A summary of the results achieved is also provided in the report
The Molecular Line Opacity of MgH in Cool Stellar Atmospheres
A new, complete, theoretical rotational and vibrational line list for the A-X
electronic transition in MgH is presented. The list includes transition
energies and oscillator strengths for all possible allowed transitions and was
computed using the best available theoretical potential energies and dipole
transition moment function with the former adjusted to account for experimental
data. The A-X line list, as well as new line lists for the B'-X and the X-X
(pure rovibrational) transitions, were included in comprehensive stellar
atmosphere models for M, L, and T dwarfs and solar-type stars. The resulting
spectra, when compared to models lacking MgH, show that MgH provides
significant opacity in the visible between 4400 and 5600 Angstrom. Further,
comparison of the spectra obtained with the current line list to spectra
obtained using the line list constructed by Kurucz (1993) show that the Kurucz
list significantly overestimates the opacity due to MgH particularly for the
bands near 5150 and 4800 Angstrom with the discrepancy increasing with
decreasing effective temperature.Comment: 10 pages, 4 figures, 3 table
Star Formation triggered by cloud-cloud collisions
We present the results of SPH simulations in which two clouds, each having
mass and radius
, collide head-on at relative velocities of
. There is a clear trend with increasing . At low
, star formation starts later, and the shock-compressed
layer breaks up into an array of predominantly radial filaments; stars condense
out of these filaments and fall, together with residual gas, towards the centre
of the layer, to form a single large- cluster, which then evolves by
competitive accretion, producing one or two very massive protostars and a
diaspora of ejected (mainly low-mass) protostars; the pattern of filaments is
reminiscent of the hub and spokes systems identified recently by observers. At
high , star formation occurs sooner and the
shock-compressed layer breaks up into a network of filaments; the pattern of
filaments here is more like a spider's web, with several small- clusters
forming independently of one another, in cores at the intersections of
filaments, and since each core only spawns a small number of protostars, there
are fewer ejections of protostars. As the relative velocity is increased, the
{\it mean} protostellar mass increases, but the {\it maximum} protostellar mass
and the width of the mass function both decrease. We use a Minimal Spanning
Tree to analyse the spatial distributions of protostars formed at different
relative velocities.Comment: 10 pages, 11 figure
Advocating co-productive engagement with marginalised people: a specific perspective on and by survivors of childhood sexual abuse
Co-production is gaining ground as a key dimension of public policy reform across the globe.This paper argues in favour of social welfare shaped by the principles of co-production and suggests that the promotion of democratic relationships is more likely to enable the agency and recovery of victim-survivors of childhood sexual abuse. The paper, based on an autoethnographical approach, is likely to be of relevance to social care practitioners who work with a range of marginalised people, particularly in liberal states that promote organisational cultures shaped disproportionately by risk. Cultures of risk, it is argued, promote power balances and ‘othering’, arguably an institutional perpetuation of the original abuse. Co-production, on the other hand, has the potential to legitimise expertise by experience, enabling victim-survivors to be reinstated as citizens with associated rights of participation. The paper subsequently draws out some of the benefits of co-production for practitioners whose professional engagement may be stifled. We suggest that co-production potentially points towards practice based on the valuing of expertise by experience and social solidarity
The Molecular Continuum Opacity of MgH in Cool Stellar Atmospheres
The opacity due to photodissociation of 24MgH is investigated in the
atmospheres of cool stars. The lowest two electronic transitions A 2Pi -- X
2Sigma+ and B' 2Sigma+ -- X 2 Sigma+ are considered where the cross sections
for the latter were published previously (Weck, Stancil, & Kirby 2002) while
the former are presented in this work. Model atmospheres calculated with the
PHOENIX code are used to investigate the effect of the photodissociation
opacity on spectra of cool stars. The A -- X photodissociation cross sections
are obtained using a combination of ab initio and experimentally derived
potential curves and dipole transition moments. Partial cross sections have
been evaluated over the accessible wavelength range 1770-4560 Angstrom for all
rotational transitions from the vibrational levels v''=0-11. Assuming a
Boltzmann distribution of the rovibrational levels of the X 2Sigma+ state, LTE
photodissociation cross sections are presented for temperatures between 1000
and 5000 K. Shape resonances, arising from rotational predissociation of
quasi-bound levels of the A 2Pi state near threshold, characterize the LTE
photodissociation cross sections. A sum rule is proposed as a check on the
accuracy of the photodissociation calculations.Comment: 9 pages, 8 figure
The Prosocial Framework: Theory, Practice and Applications Within Schools
Recent collaborations across psychological and evolutionary science have resulted in the emergence of an intervention programme for increasing the cohesion and effectiveness of human group processes. Prosocial (Atkins et al., 2019) combines Acceptance & Commitment Therapy (ACT; S. Hayes et al., 2012) and Multi-Level Selection Theory (Wilson & Sober, 1994) with Nobel Laureate Elinor Ostrom’s Core Design Principles (CDPs) for effective group-level processes (Ostrom, 2012, 2015). Ostrom’s work was ground-breaking but, being primarily descriptive in nature, did not provide a full account of the processes and procedures required to implement the CDPs. The current paper outlines the theoretical underpinnings of Prosocial and offers guidelines for its application within educational communities, providing specific examples of the wide array of ways in which the approach can be applied by professionals such as educational psychologists (EPs) to bring about positive change at the systemic level
Towards understanding interactions between Sustainable Development Goals: the role of environment–human linkages
Only 10 years remain to achieve all Sustainable Development Goals (SDGs) globally, so there is a growing need to increase the effectiveness and efficiency of action by targeting multiple SDGs. The SDGs were conceived as an ‘indivisible whole’, but interactions between SDGs need to be better understood. Several previous assessments have begun to explore interactions including synergies and possible conflicts between the SDGs, and differ widely in their conclusions. Although some highlight the role of the more environmentally-focused SDGs in underpinning sustainable development, none specifically focuses on environment-human linkages. Assessing interactions between SDGs, and the influence of environment on them, can make an important contribution to informing decisions in 2020 and beyond.
Here, we review previous assessments of interactions among SDGs, apply an influence matrix to assess pairwise interactions between all SDGs, and show how viewing these from the perspective of environment-human linkages can influence the outcome.
Environment, and environment-human linkages, influence most interactions between SDGs. Our action-focused assessment enables decision makers to focus environmental management to have the greatest impacts, and to identify opportunities to build on synergies and reduce trade-offs between particular SDGs. It may enable sectoral decision makers to seek support from environment managers for achieving their goals.
We explore cross-cutting issues and the relevance and potential application of our approach in supporting decision making for progress to achieve the SDGs
Gut microbiota composition is associated with environmental landscape in honey bees.
There is growing recognition that the gut microbial community regulates a wide variety of important functions in its animal hosts, including host health. However, the complex interactions between gut microbes and environment are still unclear. Honey bees are ecologically and economically important pollinators that host a core gut microbial community that is thought to be constant across populations. Here, we examined whether the composition of the gut microbial community of honey bees is affected by the environmental landscape the bees are exposed to. We placed honey bee colonies reared under identical conditions in two main landscape types for 6 weeks: either oilseed rape farmland or agricultural farmland distant to fields of flowering oilseed rape. The gut bacterial communities of adult bees from the colonies were then characterized and compared based on amplicon sequencing of the 16S rRNA gene. While previous studies have delineated a characteristic core set of bacteria inhabiting the honey bee gut, our results suggest that the broad environment that bees are exposed to has some influence on the relative abundance of some members of that microbial community. This includes known dominant taxa thought to have functions in nutrition and health. Our results provide evidence for an influence of landscape exposure on honey bee microbial community and highlight the potential effect of exposure to different environmental parameters, such as forage type and neonicotinoid pesticides, on key honey bee gut bacteria. This work emphasizes the complexity of the relationship between the host, its gut bacteria, and the environment and identifies target microbial taxa for functional analyses
Efficient deformable motion correction for 3-D abdominal MRI using manifold regression
We present a novel framework for efficient retrospective respiratory motion correction of 3-D abdominal MRI using manifold regression. K-space data are continuously acquired under free breathing using the stack-of-stars radial gold-en-angle trajectory. The stack-of-profiles (SoP) from all temporal positions are embedded into a common manifold, in which SoPs that were acquired at similar respiratory states are close together. Next, the SoPs in the manifold are clustered into groups using the k-means algorithm. One 3-D volume is reconstructed at the central SoP position of each cluster (a.k.a. key-volumes). Motion fields are estimated using deformable image registration between each of these key-volumes and a reference end-exhale volume. Subsequently, the motion field at any other SoP position in the manifold is derived using manifold regression. The regressed motion fields for each of the SoPs are used to deter-mine a final motion-corrected MRI volume. The method was evaluated on realistic synthetic datasets which were generated from real MRI data and also tested on an in vivo dataset. The framework enables more accurate motion correction compared to the conventional binning-based approach, with high computational efficiency
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