1,381 research outputs found
Simulation and optimisation of terahertz emission from InGaAs and InP photoconductive switches
We simulate the terahertz emission from laterally-biased InGaAs and InP using
a three-dimensional carrier dynamics model in order to optimise the
semiconductor material. Incident pump-pulse parameters of current Ti:Sapphire
and Er:fibre lasers are chosen, and the simulation models the semiconductor's
bandstructure using parabolic Gamma, L and X valleys, and heavy holes. The
emitted terahertz radiation is propagated within the semiconductor and into
free space using a model based on the Drude-Lorentz dielectric function. As the
InGaAs alloy approaches InAs an increase in the emitted power is observed, and
this is attributed to a greater electron mobility. Additionally,
low-temperature grown and ion-implanted InGaAs are modelled using a finite
carrier trapping time. At sub-picosecond trapping times the terahertz bandwidth
is found to increase significantly at the cost of a reduced emission power.Comment: 9 pages, 7 figure
Consumer-based brand equity and brand performance
The relation between consumer-based brand equity and brand performance was investigated across 15 product categories in Brazil and the UK. Brand equity was conceptualized as related to the level of social benefit offered by each brand and was measured with a simple questionnaire that asked consumers to rate brands with respect to their familiarity and quality levels. These measures were then related to brand market share and revenue. Results showed that the relation between consumer-based brand equity and brand performance varies across product categories, indicating that products differ with respect to their level of brandability and suggesting ways to measure it
Susceptibility inhomogeneity and non-Fermi liquid behavior in UCu_{5-x}Pt_x
Transverse-field muSR shifts and relaxation rates have been measured in the
non-Fermi liquid (NFL) alloy system UCu_{5-x}Pt_x, x = 1.0, 1.5, and 2.5. At
low temperatures the fractional spread in Knight shifts delta K/K approx
deltachi/chi is gtrsim 2 for x = 1, but is only half this value for x = 1.5 and
2.5. In a disorder-driven scenario where the NFL behavior is due to a broadly
distributed (Kondo or Griffiths-phase cluster) characteristic energy E, our
results indicate that delta E/E_{rm av} approx (delta K/K)_{T=0} is similar for
UCu_{5-x}Pd_x (x = 1 and 1.5) and UCu_4Pt, but is reduced for UCu_{5-x}Pt_x, x
= 1.5 and 2.5. This reduction is due to a marked increase of E with increasing
x; the spread delta E is found to be roughly independent of x. Our results
correlate with the observed suppression of other NFL anomalies for x > 1 in
UCu_{5-x}Pt_x but not in UCu_{5-x}Pd_x, and are further evidence for the
importance of disorder in the NFL behavior of both these alloy systems.Comment: 4 pages, 2 figures, submitted to 10th International Conference on
Muon Spin Rotation, Relaxation, and Resonance, Oxford, UK, August 200
Non-Fermi-liquid behavior in the Kondo lattices induced by peculiarities of magnetic ordering and spin dynamics
A scaling consideration of the Kondo lattices is performed with account of
singularities in the spin excitation spectral function. It is shown that a
non-Fermi-liquid (NFL) behavior between two critical values of the bare
coupling constant occurs naturally for complicated magnetic structures with
several magnon branches. This may explain the fact that a NFL behavior takes
place often in the heavy-fermion systems with peculiar spin dynamics. Another
kind of a NFL-like state (with different critical exponents) can occur for
simple antiferromagnets with account of magnon damping, and for paramagnets,
especially with two-dimensional character of spin fluctuations. The mechanisms
proposed lead to some predictions about behavior of specific heat, resistivity,
magnetic susceptibility, and anisotropy parameter, which can be verified
experimentally.Comment: 16 pages, RevTeX, 4 Postscript figures. Extended versio
The effect of mirabegron on patient-related outcomes in patients with overactive bladder: the results of post hoc correlation and responder analyses using pooled data from three randomized Phase III trials
Purpose To understand how improvements in the symptoms
of overactive bladder (OAB) seen with the b3-adrenoceptor
agonist mirabegron 50 mg, correlate with patient experience
as measured by validated and standard patient-reported
outcomes (PROs), and to identify whether there is overall
directional consistency in the responsiveness of PROs to
treatment effect.
Methods In a post hoc analysis of pooled data from three
randomized, double-blind, placebo-controlled, 12-week
Phase III trials of mirabegron 50 mg once daily, responder
rates for incontinence frequency (C50 % reduction in
incontinence episodes/24 h from baseline to final visit),
micturition frequency (B8 micturitions/24 h at final visit),
and PROs [minimally important differences in patient
perception of bladder condition (PPBC) and subsets of the
overactive bladder questionnaire (OAB-q) measuring total
health-related quality of life (HRQoL), and symptom
bother] were evaluated individually and in combination.
Results Mirabegron 50 mg demonstrated greater
improvement from baseline to final visit than placebo for
each of the responder analyses, whether for individual
objective and subjective outcomes or combinations thereof.
These improvements versus placebo were statistically significant
for all double and triple responder analyses and for
all single responder analyses except PPBC. PRO measurements
showed directional consistency and significant
correlations, and there were also significant correlations
between objective and subjective measures of efficacy.
Conclusions The improvements in objective measures
seen with mirabegron 50 mg translate into a meaningful
clinical benefit as evident by the directional consistency
seen in HRQoL measures of benefit
Prevalência da infecção pelo vírus da hepatite C em comunidades remanescentes de quilombos no Brasil Central
In order to determine the prevalence of hepatitis C virus (HCV) infection in quilombo remnant communities in Central Brazil, 1,007 subjects were interviewed in all 12 communities existing in Mato Grosso do Sul State, Central Brazil. Blood samples were collected and sera were tested for anti-HCV by enzyme-linked immunosorbent assay. Positive samples were retested for confirmation using a line immunoassay and were also subjected to HCV RNA detection. The prevalence of HCV infection was 0.2%. This finding shows a low prevalence of HCV infection in quilombo remnant communities in Central Brazil.Com objetivo de estimar a prevalência da infecção pelo vírus da hepatite C (HCV) em comunidades remanescentes de quilombos no Brasil Central, 1.007 indivíduos foram entrevistados nas 12 comunidades quilombolas existentes no Estado de Mato Grosso do Sul, Brasil Central. Amostras sanguíneas foram coletadas e os soros testados para anti-HCV pelo ensaio imunoenzimático. As amostras positivas foram testadas pelo ensaio confirmatório "line immunoassay" e também submetidas à detecção do RNA-HCV. A prevalência da infecção pelo HCV foi de 0,2%. Este achado mostra uma baixa prevalência da infecção pelo HCV em comunidades remanescentes de quilombos no Brasil Central
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