438 research outputs found
Towards an Islamic Discourse of Uncertainty and Doubt
Contemporary Islam is witnessing the advent of new critical discourses from within its own modes of articulation. It confronts a new epistemic and interpretative situation, which is generally felt as something of an emergency. This emergency in epistemology and hermeneutics is largely the result of a radical shift of the categories of modern philosophy, science, culture and geography. Given the fact that the exploratory elaboration of law for centuries has been the dominant mode of self-expression in Islam, one of the key themes of contemporary Shici thought is the search for a legal identity. The current debate on the sharica (divine law) in Iran underscores the continued significance of this exploration. In the debate, the radical post-modernist cAbd al-Karim Surush contests the epistemic certainty of eternal knowledge, so common among modernists
Tentative detection of the gravitational magnification of type Ia supernovae
The flux from distant type Ia supernovae (SN) is likely to be amplified or
de-amplified by gravitational lensing due to matter distributions along the
line-of-sight. A gravitationally lensed SN would appear brighter or fainter
than the average SN at a particular redshift. We estimate the magnification of
26 SNe in the GOODS fields and search for a correlation with the residual
magnitudes of the SNe. The residual magnitude, i.e. the difference between
observed and average magnitude predicted by the "concordance model" of the
Universe, indicates the deviation in flux from the average SN. The linear
correlation coefficient for this sample is r=0.29. For a similar, but
uncorrelated sample, the probability of obtaining a correlation coefficient
equal to or higher than this value is ~10%, i.e. a tentative detection of
lensing at ~90% confidence level. Although the evidence for a correlation is
weak, our result is in accordance with what could be expected given the small
size of the sample.Comment: 7 pages, 2 figure
Medical students at LTC and in pre-hospital care: a structured programme in pre-hospital emergency medicine for medical undergraduates
SNOC: a Monte-Carlo simulation package for high-z supernova observations
We present a Monte-Carlo package for simulation of high-redshift supernova
data, SNOC. Optical and near-infrared photons from supernovae are ray-traced
over cosmological distances from the simulated host galaxy to the observer at
Earth. The distances to the sources are calculated from user provided
cosmological parameters in a Friedmann-Lemaitre universe, allowing for
arbitrary forms of ``dark energy''. The code takes into account gravitational
interactions (lensing) and extinction by dust, both in the host galaxy and in
the line-of-sight. The user can also choose to include exotic effects like a
hypothetical attenuation due to photon-axion oscillations. SNOC is primarily
useful for estimations of cosmological parameter uncertainties from studies of
apparent brightness of Type Ia supernovae vs redshift, with special emphasis on
potential systematic effects. It can also be used to compute standard
cosmological quantities like luminosity distance, lookback time and age of the
universe in any Friedmann-Lemaitre model with or without quintessence.Comment: 16 pages, 3 figure
Near-IR search for lensed supernovae behind galaxy clusters: III. Implications for cluster modeling and cosmology
Massive galaxy clusters at intermediate redshifts act as gravitational lenses
that can magnify supernovae (SNe) occurring in background galaxies. We assess
the possibility to use lensed SNe to put constraints on the mass models of
galaxy clusters and the Hubble parameter at high redshift. Due to the standard
candle nature of Type Ia supernovae (SNe Ia), observational information on the
lensing magnification from an intervening galaxy cluster can be used to
constrain the model for the cluster mass distribution. A statistical analysis
using parametric cluster models was performed to investigate the possible
improvements from lensed SNe Ia for the accurately modeled galaxy cluster A1689
and the less well constrained cluster A2204. Time delay measurements obtained
from SNe lensed by accurately modeled galaxy clusters can be used to measure
the Hubble parameter. For a survey of A1689 we estimate the expected rate of
detectable SNe Ia and of multiply imaged SNe. The velocity dispersion and core
radius of the main cluster potential show strong correlations with the
predicted magnifications and can therefore be constrained by observations of
SNe Ia in background galaxies. This technique proves especially powerful for
galaxy clusters with only few known multiple image systems. The main
uncertainty for measurements of the Hubble parameter from the time delay of
strongly lensed SNe is due to cluster model uncertainties. For the extremely
well modeled cluster A1689, a single time delay measurement could be used to
determine the Hubble parameter with a precision of ~ 10%. We conclude that
observations of SNe Ia behind galaxy clusters can be used to improve the mass
modeling of the large scale component of galaxy clusters and thus the
distribution of dark matter. Time delays from SNe strongly lensed by accurately
modeled galaxy clusters can be used to measure the Hubble constant at high
redshifts.Comment: 10 pages, 8 figures, 3 tables. Accepted for publication in A&
Soft tissue tumors: Pericytoma with t(7;12)
Review on Soft tissue tumors: Pericytoma with t(7;12), with data on clinics, and the genes involved
GLI1 (glioma-associated oncogene homolog 1)
Review on GLI1 (glioma-associated oncogene homolog 1), with data on DNA, on the protein encoded, and where the gene is implicated
ACTB (actin, beta)
Review on ACTB (actin, beta), with data on DNA, on the protein encoded, and where the gene is implicated
A standard, single dose of inhaled terbutaline attenuates hyperpnoea-induced bronchoconstriction and mast cell activation in athletes
Release of broncho-active mediators from mast cells during exercise hyperpnoea is a key factor in the pathophysiology of exercise-induced bronchoconstriction (EIB). Our aim was to investigate the effect of a standard, single dose of an inhaled ÎČ2-adrenoceptor agonist on mast cell activation in response to dry air hyperpnoea in athletes with EIB. Twenty-seven athletes with EIB completed a randomised, double blind, placebo-controlled, crossover study. Terbutaline (0.5 mg) or placebo was inhaled15 min prior to 8 min of eucapnic voluntary hyperpnoea (EVH) with dry air. Pre- and post-bronchial challenge, urine samples were analysed by enzyme immunoassay for 11ÎČ-prostaglandin(PG)F2α. The maximum fall in forced expiratory volume in 1 sec(FEV1) of 14 (12-20)% (median and interquartile range) following placebo was attenuated to 7 (5-9)% with the administration of terbutaline (P<0.001). EVH caused a significant increase in 11ÎČ-PGF2α from (27-57) ng·mmol creatinine-1 at baseline to (43-72) ng·mmol creatinine-1 at its peak post-EVH following placebo (P=0.002). The rise in 11ÎČ-PGF2α was inhibited with administration of terbutaline: 39 (28-44) ng·mmol creatinine-1 at baseline vs. 40 (33-58) ng·mmol creatinine-1 at its peak post-EVH (P=0.118). These data provide novel in vivo evidence of mast cell stabilisation following inhalation of a standard dose of terbutaline prior to bronchial provocation with EVH in athletes with EIB
Evolution in the Volumetric Type Ia Supernova Rate from the Supernova Legacy Survey
We present a measurement of the volumetric Type Ia supernova (SN Ia) rate
(SNR_Ia) as a function of redshift for the first four years of data from the
Canada-France-Hawaii Telescope (CFHT) Supernova Legacy Survey (SNLS). This
analysis includes 286 spectroscopically confirmed and more than 400 additional
photometrically identified SNe Ia within the redshift range 0.1<z<1.1. The
volumetric SNR_Ia evolution is consistent with a rise to z~1.0 that follows a
power-law of the form (1+z)^alpha, with alpha=2.11+/-0.28. This evolutionary
trend in the SNLS rates is slightly shallower than that of the cosmic
star-formation history over the same redshift range. We combine the SNLS rate
measurements with those from other surveys that complement the SNLS redshift
range, and fit various simple SN Ia delay-time distribution (DTD) models to the
combined data. A simple power-law model for the DTD (i.e., proportional to
t^-beta) yields values from beta=0.98+/-0.05 to beta=1.15+/-0.08 depending on
the parameterization of the cosmic star formation history. A two-component
model, where SNR_Ia is dependent on stellar mass (Mstellar) and star formation
rate (SFR) as SNR_Ia(z)=AxMstellar(z) + BxSFR(z), yields the coefficients
A=1.9+/-0.1 SNe/yr/M_solar and B=3.3+/-0.2 SNe/yr/(M_solar/yr). More general
two-component models also fit the data well, but single Gaussian or exponential
DTDs provide significantly poorer matches. Finally, we split the SNLS sample
into two populations by the light curve width (stretch), and show that the
general behavior in the rates of faster-declining SNe Ia (0.8<s<1.0) is
similar, within our measurement errors, to that of the slower objects
(1.0<s<1.3) out to z~0.8.Comment: Accepted in A
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