52 research outputs found
Degree-scale galactic radio emission at 122 MHz around the North Celestial Pole with LOFAR-AARTFAAC
Large scale structure and cosmolog
Constraining the intergalactic medium at z ≈ 9.1 using LOFAR Epoch of Reionization observations
We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift ≈ 9.1 using new upper
limits on the 21-cm power spectrum measured by the LOFAR radio telescope and a prior on the ionized fraction at that redshift
estimated from recent cosmic microwave background (CMB) observations. We have used results from the reionization simulation
code GRIZZLY and a Bayesian inference framework to constrain the parameters which describe the physical state of the IGM.
We find that, if the gas heating remains negligible, an IGM with ionized fraction 0.13 and a distribution of the ionized regions
with a characteristic size 8 h−1 comoving megaparsec (Mpc) and a full width at half-maximum (FWHM) 16 h−1 Mpc is
ruled out. For an IGM with a uniform spin temperature TS 3 K, no constraints on the ionized component can be computed. If
the large-scale fluctuations of the signal are driven by spin temperature fluctuations, an IGM with a volume fraction 0.34 of
heated regions with a temperature larger than CMB, average gas temperature 7–160 K, and a distribution of the heated regions
with characteristic size 3.5–70 h−1 Mpc and FWHM of 110 h−1 Mpc is ruled out. These constraints are within the 95 per cent
credible intervals. With more stringent future upper limits from LOFAR at multiple redshifts, the constraints will become tighter
and will exclude an increasingly large region of the parameter space
First observation of the decay and a measurement of the ratio of branching fractions
The first observation of the decay using
data collected by the LHCb detector at a centre-of-mass energy of 7 TeV,
corresponding to an integrated luminosity of 36 pb, is reported. A
signal of events is obtained and the absence of signal is
rejected with a statistical significance of more than nine standard deviations.
The branching fraction is measured relative to
that of : , where the first uncertainty is statistical, the second systematic and
the third is due to the uncertainty on the ratio of the and
hadronisation fractions.Comment: 10 pages, 3 figures, submitted to Phys. Lett. B; ISSN 0370-269
Role of genetic testing for inherited prostate cancer risk: Philadelphia prostate cancer consensus conference 2017
Purpose: Guidelines are limited for genetic testing for prostate cancer (PCA). The goal of this conference was to develop an expert consensus-dri
Highly-parallelized simulation of a pixelated LArTPC on a GPU
The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype
Risk assessment (chemical and radiological) due to intake of uranium through the ingestion of drinking water around two proposed uranium mining areas, Jharkhan d, India
Uranium is known for both chemical and radiological
toxicity. East Singhbhum is known for uranium mining, and radionuclides
can be expected in its groundwater. Groundwater was collected around
two proposed sites of Bagjata and Banduhurang and analysed for U(nat).
The study reveals that the U(nat) varied from <0.5–11.2 and <0.5–27.5 µg.L
-1 for the Bagjata and Banduhurang mining areas, respectively.
The excess lifetime cancer risk due to the consumption of uranium
in water was calculated to be in the range of 8.81 × 10-6 to
4.34 × 10-5 and 3.36 × 10-6 to 9.55 × 10-5 for
the two study areas, which are within the acceptable cancer risk
value of 1 × 10-4. However, the risk at a few locations
is very close to the threshold value. The chemical risk evaluated
by the hazard quotient was found to be within 0.05–0.23 and 0.02–0.6
for the two study areas and did not exceed the limit of 1. Thus,
the concentration of U(nat) in the groundwater presently does not
pose any serious threat to local people but must be monitored periodically
and adequate actions must be taken in the few areas with elevated
levels of uranium in the groundwater
Interaction effects of teachers’ job involvement on participation in technical decisions and organizational citizenship behaviour
Increasing participation in decision making by teachers in educational
institutions promote institutional effectiveness. Past research has
focused on the differential relationships of teachers' participation in
decision making and organizational citizenship behaviour. However, no
systematic effort has been undertaken yet to explore interaction effects
between participation in decision making and organizational citizenship
behaviour. Present study predicts teachers' job involvement would act as
moderator to influence the strength of the relationship between
participation in decision making and organizational citizenship
behaviour. Hierarchical multiple regression analyses were conducted to
test the hypotheses formulated for the study. Data were collected for the
655 faculty members working in private engineering institutions,
affiliated to JNT University, India. Results supported the role of job
involvement as potential moderator between participation in technical
decision making and organizational citizenship behaviour. The
implications of the study are relevant to the administrators, head of the
department and all the people holding power in engineering institutions
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