4,204 research outputs found
The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data
Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from interâtidal, coastal and upland environments with a range of <sup>137</sup>Cs activity concentrations and depositional histories. Estimates of the integrated <sup>137</sup>Cs activity (âinventoryâ) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5â10 km line spacing can produce useful data
Modelling the evolution of distributions : an application to major league baseball
We develop Bayesian techniques for modelling the evolution of entire distributions over time and apply them to the distribution of team performance in Major League baseball for the period 1901-2000. Such models offer insight into many key issues (e.g. competitive balance) in a way that regression-based models cannot. The models involve discretizing the distribution and then modelling the evolution of the bins over time through transition probability matrices. We allow for these matrices to vary over time and across teams. We find that, with one exception, the transition probability matrices (and, hence, competitive balance) have been remarkably constant across time and over teams. The one exception is the Yankees, who have outperformed all other teams
A large-scale proteogenomics study of apicomplexan pathogens-Toxoplasma gondii and Neospora caninum
Proteomics data can supplement genome annotation efforts, for example being used to confirm gene models or correct gene annotation errors. Here, we present a largeâscale proteogenomics study of two important apicomplexan pathogens: Toxoplasma gondii and Neospora caninum. We queried proteomics data against a panel of official and alternate gene models generated directly from RNASeq data, using several newly generated and some previously published MS datasets for this metaâanalysis. We identified a total of 201 996 and 39 953 peptideâspectrum matches for T. gondii and N. caninum, respectively, at a 1% peptide FDR threshold. This equated to the identification of 30 494 distinct peptide sequences and 2921 proteins (matches to official gene models) for T. gondii, and 8911 peptides/1273 proteins for N. caninum following stringent proteinâlevel thresholding. We have also identified 289 and 140 loci for T. gondii and N. caninum, respectively, which mapped to RNAâSeqâderived gene models used in our analysis and apparently absent from the official annotation (release 10 from EuPathDB) of these species. We present several examples in our study where the RNAâSeq evidence can help in correction of the current gene model and can help in discovery of potential new genes
Wetting to Non-wetting Transition in Sodium-Coated C_60
Based on ab initi and density-functional theory calculations, an empirical
potential is proposed to model the interaction between a fullerene molecule and
many sodium atoms. This model predicts homogeneous coverage of C_60 below 8 Na
atoms, and a progressive droplet formation above this size. The effects of
ionization, temperature, and external electric field indicate that the various,
and apparently contradictory, experimental results can indeed be put into
agreement.Comment: 4 pages, 4 postscript figure
Perceptions and experiences of mental health support for ambulance trust employees
Background: Mental ill health among ambulance staff is widespread. Evidence suggests that, with the right support, employees experiencing mental ill health can continue to work, symptom severity can be reduced and suicide prevented. Aims: To investigate ambulance staff perceptions and experiences of organisational mental health support. Methods: A cross-sectional online survey investigated work-related stressful life events and their potential psychological impact. The survey also examined staff perceptions and experiences of organisational support and acceptability of a proposed wellbeing intervention offering mandatory time to talk at work. Findings: A total of 540 ambulance staff responded. The majority reported having experienced work-related stressful life events (n=444; 82%). Associated psychological symptoms appeared to persist for years. Perceptions about organisational support related to support uptake. Stigma, fear and embarrassment were reported as barriers to disclosure and help-seeking. Mandatory time to talk at work would be acceptable (n=400; 74%). Conclusion: The association between work-related stressful events and psychological symptoms underscores the need for interventions supported at an organisation level. </jats:sec
The reaction and the magnetic dipole moment of the resonance
The reaction has been measured with
the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for
energies between = 1221--1331 MeV. Cross sections differential in
angle and energy have been determined for all particles in the final state in
three bins of the excitation energy. This reaction channel provides access to
the magnetic dipole moment of the resonance and, for the
first time, a value of has been extracted
Flexible silicon-based alpha-particle detector
The detection of alpha particles in the field can be challenging due to their short range in air of often only a few centimeters or less. This short range is a particular issue for measuring radiation inside contaminated pipework in the nuclear industry, for which there is currently no simple method available without cutting the pipes open. Here, we propose an approach for low cost, rapid, and safe identification of internally contaminated pipework based on a flexible 30 Ă 10 mm2 sheet of 50 ÎŒm thin crystalline silicon. Following established fabrication steps of pn-junction diodes, we have constructed a device with a signal-to-noise ratio of >20 in response to 5.5 MeV alpha-particles using a bespoke amplifier circuit. As flexible detectors may readily conform to a curved surface and are able to adapt to the curvature of a given pipeline, our prototype device stands out as a viable solution for nuclear decommissioning and related applications
Tackling concentrated worklessness: integrating governance and policy across and within spatial scales
Spatial concentrations of worklessness remained a key characteristic of labour markets in advanced industrial economies, even during the period of decline in aggregate levels of unemployment and economic inactivity evident from the late 1990s to the economic downturn in 2008. The failure of certain localities to benefit from wider improvements in regional and national labour markets points to a lack of effectiveness in adopted policy approaches, not least in relation to the governance arrangements and policy delivery mechanisms that seek to integrate residents of deprived areas into wider local labour markets. Through analysis of practice in the British context, we explore the difficulties of integrating economic and social policy agendas within and across spatial scales to tackle problems of concentrated worklessness. We present analysis of a number of selected case studies aimed at reducing localised worklessness and identify the possibilities and constraints for effective action given existing governance arrangements and policy priorities to promote economic competitiveness and inclusion
Robots that can adapt like animals
As robots leave the controlled environments of factories to autonomously
function in more complex, natural environments, they will have to respond to
the inevitable fact that they will become damaged. However, while animals can
quickly adapt to a wide variety of injuries, current robots cannot "think
outside the box" to find a compensatory behavior when damaged: they are limited
to their pre-specified self-sensing abilities, can diagnose only anticipated
failure modes, and require a pre-programmed contingency plan for every type of
potential damage, an impracticality for complex robots. Here we introduce an
intelligent trial and error algorithm that allows robots to adapt to damage in
less than two minutes, without requiring self-diagnosis or pre-specified
contingency plans. Before deployment, a robot exploits a novel algorithm to
create a detailed map of the space of high-performing behaviors: This map
represents the robot's intuitions about what behaviors it can perform and their
value. If the robot is damaged, it uses these intuitions to guide a
trial-and-error learning algorithm that conducts intelligent experiments to
rapidly discover a compensatory behavior that works in spite of the damage.
Experiments reveal successful adaptations for a legged robot injured in five
different ways, including damaged, broken, and missing legs, and for a robotic
arm with joints broken in 14 different ways. This new technique will enable
more robust, effective, autonomous robots, and suggests principles that animals
may use to adapt to injury
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