56,436 research outputs found
Flexible contract workers in inferior jobs: reappraising the evidence
There has been concern that the increase in non-standard or flexible employment contracts witnessed in many OECD economies is evidence of a growth in low-pay, low-quality jobs. In practice, however, it is difficult to evaluate the `quality' of flexible jobs. Previous research has either investigated objective measures of job quality such as wages and training or subjective measures such as job satisfaction. In this paper, we seek to jointly evaluate objective and subjective elements of flexible employment contracts. Specifically we develop and use an index of job quality that incorporates both subjective and objective elements. Analysis of this index demonstrates that flexible jobs are of a lower quality. However, this approach suggests that analysis of, for instance, job satisfaction alone overstates the negative impact of flexible contracts on workers.
Improved determination of the atmospheric parameters of the pulsating sdB star Feige 48
As part of a multifaceted effort to exploit better the asteroseismological
potential of the pulsating sdB star Feige 48, we present an improved
spectroscopic analysis of that star based on new grids of NLTE, fully
line-blanketed model atmospheres. To that end, we gathered four high S/N
time-averaged optical spectra of varying spectral resolution from 1.0 \AA\ to
8.7 \AA, and we made use of the results of four independent studies to fix the
abundances of the most important metals in the atmosphere of Feige 48. The mean
atmospheric parameters we obtained from our four spectra of Feige 48 are :
Teff= 29,850 60 K, log = 5.46 0.01, and log N(He)/N(H) =
2.88 0.02. We also modeled for the first time the He II line at 1640
\AA\ from the STIS archive spectrum of the star and we found with this line an
effective temperature and a surface gravity that match well the values obtained
with the optical data. With some fine tuning of the abundances of the metals
visible in the optical domain we were able to achieve a very good agreement
between our best available spectrum and our best-fitting synthetic one. Our
derived atmospheric parameters for Feige 48 are in rather good agreement with
previous estimates based on less sophisticated models. This underlines the
relatively small effects of the NLTE approach combined with line blanketing in
the atmosphere of this particular star, implying that the current estimates of
the atmospheric parameters of Feige 48 are reliable and secure.Comment: Accepted for publication in ApJ, April 201
1-loop contribution to the dynamical exponents in spin glasses
We evaluate the corrections to the mean field values of the and the
exponents at the first order in the -expansion, for . We find
that both and are decreasing when the space dimension decreases.Comment: 12 pages 3 Postscript figure
Getting diverse students and staff to talk about integration on campus, and what they say when they do: A UK-India collaborative case study.
This paper reports the early stages of a UKIERI-funded project, âWidening Participation: Diversity, isolation or integration in Higher Education?â.The project is concerned with greater equity, social justice, community and social cohesion within the current globalised, market oriented context of higher education (HE), and with enabling students to be better prepared for, and thrive in social networks and work-related arenas which are increasingly diverse, multicultural, interdependent and global.
The main aim of this 3 year project is to explore the nature of social cohesion, integration and separation, diversity, equality and discrimination experienced by diverse, minority, disadvantaged and under-represented students attending HE in UK and India.
Group stereotypes are often subconsciously held, emerging into consciousness only when they appear confirmed or confounded by personal experience or public events. Where there is little knowledge or personal experience then reliance upon group stereotypes is more likely (Kunda & Thagard, 1996). This can impact upon student and staff expectations of, responses to, and interactions with each other.
Individual studentsâ experiences and perceptions lie at the core of this project, but the ultimate purpose is to illuminate our understanding as to how these are mediated, shaped and formed, in relation to and in interaction with the structures and contextual features of the educational environments in which they, as students, are located. It is thus framed by socio-cultural rather than psychological or therapeutic theories and is located within a social-constructivist perspective (Moore, 2000). Social constructivism facilitates the development of improved understandings of educational and social environments that shape rather than determine individual dispositions towards social diversity encountered on campus. It is highly suited to the understanding of perceptions, and exploring resonances with actions, reactions and interactions.
The initial stage of this project involved inviting students and staff (academic and support staff) from five HE colleges and universities in England and India to keep a record (written and photographic) of what for them seemed to be important and relevant events relating to what they saw, heard, did and experienced on campus for a period of 1 month, in teaching, learning and social situations; namely interactions in classes and social settings; what seem to be good experiences and what seem to be negative ones; how and if their particular knowledge and experiences were used, valued and incorporated into their HE experience and learning or how they were negated. A sample size of 90 record keepers was sought across the participating institutions.
Getting that sample presented significant difficulties to all but one of the participating institutions, and raised questions about
âą the methods initially adopted,
âą the general willingness of students and staff to address and share issues relating to diversity, equality, social cohesion and integration on HE campuses with researchers
âą cultural differences in accessing respondents to take part in the research
Additional data collection methods were adopted and by January 2009 the intended sample size almost met.
This paper will address the problems encountered in undertaking the first stage of this research and present initial findings from the data that were eventually obtained
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Migrant workers in the East Midlands labour market 2010
This report is an update of previous intelligence (Migrant Workers in the East Midlands Labour Market 2007) on the profile and economic impact of migrant labour in the East Midlands economy
Coulomb screening in mesoscopic noise: a kinetic approach
Coulomb screening, together with degeneracy, is characteristic of the
metallic electron gas. While there is little trace of its effects in transport
and noise in the bulk, at mesoscopic scales the electronic fluctuations start
to show appreciable Coulomb correlations. Within a strictly standard Boltzmann
and Fermi-liquid framework, we analyze these phenomena and their relation to
the mesoscopic fluctuation-dissipation theorem, which we prove. We identify two
distinct screening mechanisms for mesoscopic fluctuations. One is the
self-consistent response of the contact potential in a non-uniform system. The
other couples to scattering, and is an exclusively non-equilibrium process.
Contact-potential effects renormalize all thermal fluctuations, at all scales.
Collisional effects are relatively short-ranged and modify non-equilibrium
noise. We discuss ways to detect these differences experimentally.Comment: Source: REVTEX. 16 pp.; 7 Postscript figs. Accepted for publication
in J. Phys.: Cond. Ma
Four-quark flux distribution and binding in lattice SU(2)
The full spatial distribution of the color fields of two and four static
quarks is measured in lattice SU(2) field theory at separations up to 1 fm at
beta=2.4. The four-quark case is equivalent to a qbar q qbar q system in SU(2)
and is relevant to meson-meson interactions. By subtracting two-body flux tubes
from the four-quark distribution we isolate the flux contribution connected
with the four-body binding energy. This contribution is further studied using a
model for the binding energies. Lattice sum rules for two and four quarks are
used to verify the results.Comment: 46 pages including 71 eps figures. 3D color figures are available at
www.physics.helsinki.fi/~ppennane/pics
Ballistic transport is dissipative: the why and how
In the ballistic limit, the Landauer conductance steps of a mesoscopic
quantum wire have been explained by coherent and dissipationless transmission
of individual electrons across a one-dimensional barrier. This leaves untouched
the central issue of conduction: a quantum wire, albeit ballistic, has finite
resistance and so must dissipate energy. Exactly HOW does the quantum wire shed
its excess electrical energy? We show that the answer is provided, uniquely, by
many-body quantum kinetics. Not only does this inevitably lead to universal
quantization of the conductance, in spite of dissipation; it fully resolves a
baffling experimental result in quantum-point-contact noise. The underlying
physics rests crucially upon the action of the conservation laws in these open
metallic systems.Comment: Invited Viewpoint articl
First observational application of a connectivity--based helicity flux density
Measuring the magnetic helicity distribution in the solar corona can help in
understanding the trigger of solar eruptive events because magnetic helicity is
believed to play a key role in solar activity due to its conservation property.
A new method for computing the photospheric distribution of the helicity flux
was recently developed. This method takes into account the magnetic field
connectivity whereas previous methods were based on photospheric signatures
only. This novel method maps the true injection of magnetic helicity in active
regions. We applied this method for the first time to an observed active
region, NOAA 11158, which was the source of intense flaring activity. We used
high-resolution vector magnetograms from the SDO/HMI instrument to compute the
photospheric flux transport velocities and to perform a nonlinear force-free
magnetic field extrapolation. We determined and compared the magnetic helicity
flux distribution using a purely photospheric as well as a connectivity-based
method. While the new connectivity-based method confirms the mixed pattern of
the helicity flux in NOAA 11158, it also reveals a different, and more correct,
distribution of the helicity injection. This distribution can be important for
explaining the likelihood of an eruption from the active region. The
connectivity-based approach is a robust method for computing the magnetic
helicity flux, which can be used to study the link between magnetic helicity
and eruptivity of observed active regions.Comment: 4 pages, 3 figures; published online in A&A 555, L6 (2013
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