20 research outputs found
A precise determination of the Bc mass from dynamical lattice QCD
We perform a precise calculation of the mass of the B_c meson using
unquenched configurations from the MILC collaboration including 2+1 flavours of
improved staggered quarks. Lattice NRQCD and the Fermilab formalism are used to
describe the b and c quarks respectively. We find the mass of the B_c meson to
be 6.304(16) GeVComment: Talk presented at Lattice2004(heavy), Fermilab, June 21-26. 3 pages,
2 figure
Spin fluctuations in nearly magnetic metals from ab-initio dynamical spin susceptibility calculations:application to Pd and Cr95V5
We describe our theoretical formalism and computational scheme for making
ab-initio calculations of the dynamic paramagnetic spin susceptibilities of
metals and alloys at finite temperatures. Its basis is Time-Dependent Density
Functional Theory within an electronic multiple scattering, imaginary time
Green function formalism. Results receive a natural interpretation in terms of
overdamped oscillator systems making them suitable for incorporation into spin
fluctuation theories. For illustration we apply our method to the nearly
ferromagnetic metal Pd and the nearly antiferromagnetic chromium alloy Cr95V5.
We compare and contrast the spin dynamics of these two metals and in each case
identify those fluctuations with relaxation times much longer than typical
electronic `hopping times'Comment: 21 pages, 9 figures. To appear in Physical Review B (July 2000
The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation
We give a theoretical analysis of published experimental studies of the
effects of impurities and disorder on the superconducting transition
temperature, T_c, of the organic molecular crystals kappa-ET_2X and beta-ET_2X
(where ET is bis(ethylenedithio)tetrathiafulvalene and X is an anion eg I_3).
The Abrikosov-Gorkov (AG) formula describes the suppression of T_c both by
magnetic impurities in singlet superconductors, including s-wave
superconductors and by non-magnetic impurities in a non-s-wave superconductor.
We show that various sources of disorder lead to the suppression of T_c as
described by the AG formula. This is confirmed by the excellent fit to the
data, the fact that these materials are in the clean limit and the excellent
agreement between the value of the interlayer hopping integral, t_perp,
calculated from this fit and the value of t_perp found from angular-dependant
magnetoresistance and quantum oscillation experiments. If the disorder is, as
seems most likely, non-magnetic then the pairing state cannot be s-wave. We
show that the cooling rate dependence of the magnetisation is inconsistent with
paramagnetic impurities. Triplet pairing is ruled out by several experiments.
If the disorder is non-magnetic then this implies that l>=2, in which case
Occam's razor suggests that d-wave pairing is realised. Given the proximity of
these materials to an antiferromagnetic Mott transition, it is possible that
the disorder leads to the formation of local magnetic moments via some novel
mechanism. Thus we conclude that either kappa-ET_2X and beta-ET_2X are d-wave
superconductors or else they display a novel mechanism for the formation of
localised moments. We suggest systematic experiments to differentiate between
these scenarios.Comment: 18 pages, 5 figure
Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry
Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase
Housing and health Paper 1: does installing heating in their homes improve the health of children with asthma?
SIGLEAvailable from British Library Document Supply Centre-DSC:m01/30918 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Birds of Conservation Concern in Eastern Acre, Brazil: Distributional Records, Occupancy Estimates, Human-Caused Mortality, and Opportunities for Ecotourism
Greisen-related scheelite, gold and sulphide mineralisation at Kirwans Hili and Bateman Creek, Reefton district, Westland, New Zealand
Temperature characteristics of positron trapping at defects in electron-irradiated silicon
Deprivation and childhood obesity: a cross sectional study of 20 973 children in Plymouth, United Kingdom
OBJECTIVE—To study the association between socioeconomic deprivation and childhood obesity.
DESIGN—Cross sectional study.
SETTING—All state primary schools in Plymouth. Plymouth is a relatively deprived city in the United Kingdom, ranking 338th of 366( )local authorities on the Department of the Environment Index of Local Conditions.
SUBJECTS—20 973 children between the ages of 5 and 14 years, 1994-96.
MAIN OUTCOME MEASURE—Numbers of obese children (body mass index (BMI) above the 98th centile) by quarters of Townsend score.
RESULTS—Plymouth had a rate of childhood obesity two and half times that expected nationally (5% v 2%). The obesity prevalence increased with age, being almost double in the oldest age quarter (boys 6.2%; girls 7.0%), compared with the youngest age quarter. Within Plymouth, there was a significant trend for higher rates of obesity related to increasing deprivation in both boys (p=0.017) and girls (p=0.018). The odds ratio (OR) for childhood obesity (highest-lowest quarter of Townsend scores) had borderline significance in boys (OR 1.29, 95% confidence intervals (CI) 1.00 to 1.65, p=0.049) but was larger and more significant in the girls (OR 1.39, 95% CI 1.08 to 1.80, p=0.011). Unlike boys, the association between obesity in girls and Townsend scores became stronger with age such that in the oldest age quarter (over 11.7 years), girls in the highest quarter of Townsend scores were nearly twice as likely be obese, as compared with the lowest quarter (OR 1.95, 95% CI 1.23 to 3.08, p=0.005). State of pubertal development could not be accounted for as this information was not available.
CONCLUSIONS—This study provides evidence for an association between deprivation and childhood obesity in this English population. The health of children from deprived households is affected by a number of adverse influences. The high prevalence of obesity in these children is yet another factor that could predispose to greater morbidity in adult life.
Keywords: childhood obesity; socioeconomic deprivation; body mass index; Townsend material deprivation scor