26,305 research outputs found
Naturalness of the Coleman-Glashow Mass Relation in the 1/N_c Expansion: an Update
A new measurement of the Xi^0 mass verifies the accuracy of the
Coleman-Glashow relation at the level predicted by the 1/N_c expansion. Values
for other baryon isospin mass splittings are updated, and continue to agree
with the 1/N_c hierarchy.Comment: 6 pages, revte
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Mental Health and Wellbeing in England: the Adult Psychiatric Morbidity Survey 2014
This report presents findings of a survey of mental illness and wellbeing among people aged 16 and over living in private households in England. The survey was commissioned by NHS Digital and funded by the Department of Health, and is the fourth in a series of surveys of adult mental health
Terrorist Attacks On Public Bus Transportation: A Preliminary Empirical Analysis, MTI Report WP 09-01
This report provides data on terrorist attacks against public bus transportation targets and serious crimes committed against such targets throughout the world. The data are drawn from the MTI database of attacks on public surface transportation, which is expanded and updated as information becomes available. This analysis is based on the database as of December 17, 2009. Data include the frequency and lethality with which buses, bus stations, and bus stops are attacked; the relationship between fatalities and attacks against bus targets and the relationship between injuries and attacks against those targets; how often, relative to other surface transportation targets, buses are attacked, first with all weapons and then with only explosive and incendiary devices; the relative lethality of attacks; and the distribution of attacks. It then presents some preliminary observations drawn from those data that can help stakeholders governments, transit managers, and employees to focus on the ways the most frequent and/or most lethal attacks are carried out as they consider measures to prevent or mitigate attacks that may be considered likely to happen in the United States
Deriving Iodine-free spectra for high-resolution echelle spectrographs
We describe a new method to derive clean, iodine-free spectra directly from
observations acquired using high-resolution echelle spectrographs equipped with
iodine cells. The main motivation to obtain iodine-free spectra is to use
portions of the spectrum that are superimposed with the dense forest of iodine
absorption lines, in order to retrieve lines that can be used to monitor the
magnetic activity of the star, helping to validate candidate planets. In short,
we provide a straight-forward methodology to clean the spectra by using the
forward model used to derive radial velocities, the Line Spread Function
information plus the stellar spectrum without iodine to reconstruct and
subtract the iodine spectrum from the observations. We show our results using
observations of the star Ceti acquired with the PFS, HIRES and UCLES
spectrographs, reaching an iodine-free spectrum correction at the 1% RMS
level. We additionally discuss the limitations and further applications of the
method.Comment: 15 pages, 7 figures. Accepted for publication in A
Increases in salience of ethnic identity at work: the roles of ethnic assignation and ethnic identification
To better understand how ethnicity is actually experienced within organisations, we examined reported increases in ethnic identity salience at work and responses to such increases. Thirty British black Caribbean graduate employees were interviewed about how and when they experienced their ethnic identity at work. The findings demonstrated that increased salience in ethnic identity was experienced in two key ways: through ‘ethnic assignation’ (a ‘push’ towards ethnic identity) and ‘ethnic identification’ (a ‘pull’ towards ethnic identity). We explore how and when ethnic assignation and ethnic identification occur at work, and their relevance to how workplaces are experienced by this group of minority ethnic employees. The findings suggest the need for further research attention to the dynamic and episodic nature of social identity, including ethnic identity, within organisations, and to the impact of such increases in salience of social identities on behaviour at work
Observation of suppression of light scattering induced by dipole-dipole interactions in a cold atomic ensemble
We study the emergence of collective scattering in the presence of
dipole-dipole interactions when we illuminate a cold cloud of rubidium atoms
with a near-resonant and weak intensity laser. The size of the atomic sample is
comparable to the wavelength of light. When we gradually increase the atom
number from 1 to 450, we observe a broadening of the line, a small red shift
and, consistently with these, a strong suppression of the scattered light with
respect to the noninteracting atom case. Numerical simulations, which include
the internal atomic level structure, agree with the data.Comment: 5 pages, 5 figure
Simulating Impacts of Extreme Weather Events on Urban Transport Infrastructure in the UK
Urban areas face many risks from future climate change and their infrastructure will be placed under more pressure
due to changes in climate extremes. Using the Tyndall Centre Urban Integrated Assessment Framework, this paper
describes a methodology used to assess the impacts of future climate extremes on transport infrastructure in
London. Utilising high-resolution projections for future climate in the UK, alongside stochastic weather generators
for downscaling, urban temperature and flooding models are used to provide information on the likelihood of future
extremes. These are then coupled with spatial network models of urban transport infrastructure and, using thresholds
to define the point at which systems cease to function normally, disruption to the networks can be simulated.
Results are shown for both extreme heat and urban surface water flooding events and the impacts on the travelling
population, in terms of both disruption time and monetary cost
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