665 research outputs found
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Case Report: Resolution of chronic urticaria following treatment of odontogenic infection.
Background: Chronic spontaneous urticaria (CSU) is a condition characterised by the presence of hives with/without angioedema, that affects individuals on more days than not for 6 weeks or more. The role of infection as a potential trigger for CSU is well described, but the current clinical guidelines do not recommend routine screening for underlying infections. Main observations: We report a case of severe prolonged chronic spontaneous urticaria in a 19-year-old, that went into rapid remission following the treatment of dental infection. Conclusions: Clinicians should recognise the potential role that infection can have in causing chronic urticaria. There should be a low threshold to treat infection in such circumstances
Power Spectrum of Velocity Fluctuations in the Universe
We investigate the power spectrum of velocity fluctuations in the universe,
, starting from four different measures of velocity: (1) the power
spectrum of velocity fluctuations from peculiar velocities of galaxies; (2) the
rms peculiar velocity of galaxy clusters; (3) the power spectrum of velocity
fluctuations from the power spectrum of density fluctuations in the galaxy
distribution; (4) and the bulk velocity from peculiar velocities of galaxies.
We show that measures (1) and (2) are not consistent with each other and either
the power spectrum from peculiar velocities of galaxies is overestimated or the
rms cluster peculiar velocity is underestimated. The amplitude of velocity
fluctuations derived from the galaxy distribution (measure 3) depends on the
parameter . We estimate the parameter on the basis of measures
(2) and (4). The power spectrum of velocity fluctuations from the galaxy
distribution in the Stromlo-APM redshift survey is consistent with the observed
rms cluster velocity and with the observed large-scale bulk flow when the
parameter is in the range 0.4-0.5. In this case the value of the
function at wavelength Mpc is km s
and the rms amplitude of the bulk flow at the radius Mpc is km s. The velocity dispersion of galaxy systems originates mostly
from the large-scale velocity fluctuations with wavelengths Mpc.Comment: Astrophysical Journal, Vol. 493, in press: 23 pages, uses AAS Latex,
and 14 separate postscript figure
Steps toward the power spectrum of matter. I.The mean spectrum of galaxies
We calculate the mean power spectrum of galaxies using published power
spectra of galaxies and clusters of galaxies. On small scales we use the power
spectrum derived from the 2-dimensional distribution of APM galaxies, on large
scales we use power spectra derived from 3-dimensional data for galaxy and
cluster samples. Spectra are reduced to real space and to the amplitude of the
power spectrum of APM galaxies. Available data indicate the presence of two
different populations in the nearby Universe. Clusters of galaxies sample a
relatively large region in the Universe where rich, medium and poor
superclusters are well represented. Their mean power spectrum has a spike on
scale 120 h^{-1}Mpc, followed by an approximate power-law spectrum of index n =
-1.9 towards small scales. The power spectrum found from LCRS and IRAS 1.2 Jy
surveys is flatter around the maximum, which may represent regions of the
Universe with medium-rich and poor superclusters.Comment: LaTex (sty files added), 35 pages, 5 PostScript figures and Table
with mean power spectrum embedded, Astrophysical Journal (accepted
Microlensing by Compact Objects associated to Gas Clouds
We investigate gravitational microlensing of point-like lenses surrounded by
diffuse gas clouds. Besides gravitational bending, one must also consider
refraction and absorption phenomena. According to the cloud density, the light
curves may suffer small to large deviations from Paczynski curves, up to
complete eclipses. Moreover, the presence of the cloud endows this type of
microlensing events with a high chromaticity and absorption lines recognizable
by spectral analysis. It is possible that these objects populate the halo of
our galaxy, giving a conspicuous contribution to the fraction of the baryonic
dark matter. The required features for the extension and the mass of the cloud
to provide appreciable signatures are also met by several astrophysical
objects.Comment: 11 pages with 4 figures. Accepted by A&
Origin and evolution of halo bias in linear and non-linear regimes
We present results from a study of bias and its evolution for galaxy-size
halos in a large, high-resolution simulation of a LCDM model. We consider the
evolution of bias estimated using two-point correlation function (b_xi), power
spectrum (b_P), and a direct correlation of smoothed halo and matter
overdensity fields (b_d). We present accurate estimates of the evolution of the
matter power spectrum probed deep into the stable clustering regime
(k~[0.1-200]h/Mpc at z=0). The halo power spectrum evolves much slower than the
power spectrum of matter and has a different shape which indicates that the
bias is time- and scale-dependent. At z=0, the halo power spectrum is
anti-biased with respect to the matter power spectrum at wavenumbers
k~[0.15-30]h/Mpc, and provides an excellent match to the power spectrum of the
APM galaxies at all probed k. In particular, it nicely matches the inflection
observed in the APM power spectrum at k~0.15h/Mpc. We complement the power
spectrum analysis with a direct estimate of bias using smoothed halo and matter
overdensity fields and show that the evolution observed in the simulation in
linear and mildly non-linear regimes can be well described by the analytical
model of Mo & White (1996), if the distinction between formation redshift of
halos and observation epoch is introduced into the model. We present arguments
and evidence that at higher overdensities, the evolution of bias is
significantly affected by dynamical friction and tidal stripping operating on
the satellite halos in high-density regions of clusters and groups; we
attribute the strong anti-bias observed in the halo correlation function and
power spectrum to these effects. (Abridged)Comment: submitted to the Astrophys.Journal; 19 pages, 9 figures LaTeX (uses
emulateapj.sty
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Restructuring the Homicide Offences to Tackle Violence, Discrimination and Drugs in a Modern Society
This article argues that the current law on homicide fails to satisfy the goal of âfair labellingâ leading to an indirect risk of discrimination against vulnerable members of our society who are not being consistently recognized as the victims of a fatal crime. The case is put forward for two new rungs in the homicide ladder of âaggravated murderâ and âaggravated manslaughterâ, along with statutory offences which directly cater for the victims of drug homicides and domestic abuse leading to a suicide
Motivating Questions and Partial Answers:A Response to Prosecuting Domestic Violence by Michelle Madden Dempse
Template-stripped gold surfaces with 0.4 nm rms roughness suitable for force measurements. Application to the Casimir force in the 20-100 nm range
Using a template-stripping method, macroscopic gold surfaces with
root-mean-square (rms) roughness less than 0.4 nm have been prepared, making
them useful for studies of surface interactions in the nanometer range. The
utility of such substrates is demonstrated by measurements of the Casimir force
at surface separations between 20 and 100 nm, resulting in good agreement with
theory. The significance and quantification of this agreement is addressed, as
well as some methodological aspects regarding the measurement of the Casimir
force with high accuracy.Comment: 7 figure
Epidemics and the Politics of Knowledge: Contested Narratives in Egypt's H1N1 Response
This article explores the politics of knowledge involved in understanding and responding to epidemics in an era of global health governance and biosecurity. It develops and applies an approach focused on how multiple, competing narratives about epidemics are constructed, mobilised and interact, and selectively justify pathways of intervention and response. A detailed ethnographic case study of national and local responses to H1N1 influenza, so-called âswine fluâ, in Egypt reveals how global narratives were reworked by powerful actors in a particular political context, suppressing and delegitimizing the alternative narratives of the Zabaleen (Coptic Christian) people whose lives and livelihoods centred on raising pigs and working with them to control urban waste. The case study illustrates important ways in which geographies and politics of blame around epidemics emerge and are justified, their political contexts and consequences, and how they may feed back to shape the dynamics of disease itself.ESR
Double Inflation in Supergravity and the Large Scale Structure
The cosmological implication of a double inflation model with hybrid + new
inflations in supergravity is studied. The hybrid inflation drives an inflaton
for new inflation close to the origin through supergravity effects and new
inflation naturally occurs. If the total e-fold number of new inflation is
smaller than , both inflations produce cosmologically relevant density
fluctuations. Both cluster abundances and galaxy distributions provide strong
constraints on the parameters in the double inflation model assuming
standard cold dark matter scenario. The future satellite
experiments to measure the angular power spectrum of the cosmic microwave
background will make a precise determination of the model parameters possible.Comment: 19 pages (RevTeX file
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