4,021 research outputs found
Kondo physics in a dissipative environment
We report nonperturbative results for the interacting quantum-critical
behavior in a Bose-Fermi Kondo model describing a spin-1/2 coupled both to a
fermionic band with a pseudogap density of states and to a dissipative bosonic
bath. The model serves as a paradigm for studying the interplay between Kondo
physics and low-energy dissipative modes in strongly correlated systems.Comment: 2 pages, 2 figures. Proceedings of The International Conference on
Strongly Correlated Electron Systems (SCES'07), accepted for publication in
Physica
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The status of continuous improvement in ICiPS members in 2015
This report was commissioned following discussions in 2014, between the authors of this report and staff members from ICiPS about the paucity of relevant research about the current status of continuous (CI) in the UK. The purpose of this report is therefore, to examine the status of CI in ICiPS members in 2015, with a view to helping ICiPS serve the needs of its members, and also to provide an agenda for research organisations such as the Centre for Service Management (CSM) at Loughborough University. This report covers seven case studies and draws out common themes. In this report, CI is understood to mean: ‘where all members of the organisation work together on an ongoing basis improving processes and reducing errors to improve overall performance for the customer’ (Fryer, Antony, and Douglas, 2007, p. 498). This report is required, because although CI has been on the agenda for many years for Public Services Organisations there has not been a review as to how this has progressed recently
Two Lighthouses to Navigate: Effects of Ideal and Counter-Ideal Values on Follower Identification and Satisfaction with their Leaders
Ideals (or ideal values) help people to navigate in social life. They indicate at a very fundamental level what people are concerned about, what they strive for, and what they want to be affiliated with. Transferring this to a leader-follower analysis, our first Study (N = 306) confirms that followers’ identification and satisfaction with their leaders are stronger, the more leaders match followers’ ideal leader values. Study 2 (N = 244) extends the perspective by introducing the novel concept of counter-ideals (i.e., how an ideal leader should not be) as a second, non-redundant point of reference. Results confirm that a leader’s match on ideal and on counter-ideal values have independent effects in that both explain unique variance in followers’ identification and satisfaction with their leader. Study 3 (N = 136) replicates the previous results in an experimental scenario study and provides evidence for the proposed causal direction of the underlying process. We conclude that counter-ideal values might be an additional point of reference that people use to triangulate targets above and beyond ideal values and discuss the implications of our findings for value research and management
Economic evaluation of ASCOT-BPLA: Antihypertensive treatment with an amlodipine-based regimen is cost-effective compared to an atenolol-based regimen
Copyright © 2010 BMJ Publishing Group Ltd & British Cardiovascular Society. Internal or personal use of this material is permitted. However, permission to reprint/republish this material must be obtained from the Publisher.Objective: To compare the cost effectiveness of an amlodipine-based strategy and an atenolol-based strategy in the treatment of hypertension in the UK and Sweden.
Design: A prospective, randomised trial complemented with a Markov model to assess long-term costs and health effects.
Setting: Primary care.
Patients: Patients with moderate hypertension and three or more additional risk factors.
Interventions: Amlodipine 5–10 mg with perindopril 4–8 mg added as needed or atenolol 50–100 mg with bendroflumethiazide 1.25–2.5 mg and potassium added as needed
Main outcome measures: Cost per cardiovascular event and procedure avoided, and cost per quality-adjusted life-year gained.
Results: In the UK, the cost to avoid one cardiovascular event or procedure would be €18 965, and the cost to gain one quality-adjusted life-year would be €21 875. The corresponding figures for Sweden were €13 210 and €16 856.
Conclusions: Compared with the thresholds applied by NICE and in the Swedish National Board of Health and Welfare’s Guidelines for Cardiac Care, an amlodipine-based regimen is cost effective for the treatment of hypertension compared with an atenolol-based regimen in the population studied.The study was supported by the principal funding source, Pfizer, New York, USA
Long range transcriptional control of virulence critical genes in Mycobacterium tuberculosis by nucleoid-associated proteins?
Ground State Properties of Anderson Impurity in a Gapless Host
Using the Bethe ansatz method, we study the ground state properties of a
Anderson impurity in a ``gapless'' host, where a density of band
states vanishes at the Fermi level as . As
in metals, the impurity spin is proven to be screened at arbitrary parameters
of the system. However, the impurity occupancy as a function of the bare
impurity energy is shown to acquire novel qualitative features which
demonstrate a nonuniversal behavior of the system. The latter explains why the
Kondo screening is absent (or exists only at quite a large electron-impurity
coupling) in earlier studies based on scaling arguments.Comment: 5 pages, no figure, RevTe
Broad-band X-ray spectral evolution of GX 339-4 during a state transition
We report on X-ray and soft gamma-ray observations of the black-hole
candidate GX 339-4 during its 2007 outburst, performed with the RXTE and
INTEGRAL satellites. The hardness-intensity diagram of all RXTE/PCA data
combined shows a q-shaped track similar to that observed in previous
outbursts.The evolution in the diagram suggested that a transition from
hard-intermediate state to soft-intermediate state occurred, simultaneously
with INTEGRAL observations performed in March. The transition is confirmed by
the timing analysis presented in this work, which reveals that a weak type-A
quasi-periodic oscillation (QPO) replaces a strong type-C QPO. At the same
time, spectral analysis shows that the flux of the high-energy component shows
a significant decrease in its flux. However, we observe a delay (roughly one
day) between variations of the spectral parameters of the high-energy component
and changes in the flux and timing properties. The changes in the high-energy
component can be explained either in terms the high-energy cut-off or in terms
of a variations in the reflection component. We compare our results with those
from a similar transition during the 2004 outburst of GX 339-4.Comment: 8 pages, 6 figures, accepted for publication in MNRAS Main Journa
Comparing cancer mortality and GDP health expenditure in England and Wales with other major developed countries from 1979 to 2006
Electrochemical polymerisation of phenol in aqueous solution on a Ta/PbO2 anode
This paper deals with the treatment of aqueous phenol solutions using an electrochemical technique. Phenol can be partly eliminated from aqueous solution by electrochemically initiated polymerisation. Galvanostatic electrolyses of phenol solutions at concentration up to 0.1 mol dm−3 were carried out on a Ta/PbO2 anode. The polymers formed are insoluble in acidic medium but soluble in alkaline. These polymers were filtered and then dissolved in aqueous solution of sodium hydroxide (1 mol dm−3). The polymers formed were quantified by total organic carbon (TOC) measurement. It was found that the conversion of phenol into polymers increases as a function of initial concentration, anodic current density, temperature, and solution pH. The percentage of phenol polymerised can reach 15%
Tracing the jet contribution to the mid-IR over the 2005 outburst of GRO J1655-40 via broadband spectral modeling
We present new results from a multi-wavelength (radio/infrared/optical/X-ray)
study of the black hole X-ray binary GRO J1655-40 during its 2005 outburst. We
detected, for the first time, mid-infrared emission at 24 um from the compact
jet of a black hole X-ray binary during its hard state, when the source shows
emission from a radio compact jet as well as a strong non-thermal hard X-ray
component. These detections strongly constrain the optically thick part of the
synchrotron spectrum of the compact jet, which is consistent with being flat
over four orders of magnitude in frequency. Moreover, using this unprecedented
coverage, and especially thanks to the new Spitzer observations, we can test
broadband disk and jet models during the hard state. Two of the hard state
broadband spectra are reasonably well fitted using a jet model with parameters
overall similar to those previously found for Cyg X-1 and GX 339-4. Differences
are also present; most notably, the jet power in GRO J1655-40 appears to be a
factor of at least ~3-5 higher (depending on the distance) than that of Cyg X-1
and GX 339-4 at comparable disk luminosities. Furthermore, a few discrepancies
between the model and the data, previously not found for the other two black
hole systems for which there was no mid-IR/IR and optical coverage, are
evident, and will help to constrain and refine theoretical models.Comment: accepted for publication in Ap
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