15,355 research outputs found
Beyond the Rhetoric: Maternal, Newborn and Child Survival in Nepal
Nepal has performed exceptionally in improving reproductive, maternal and child health outcomes over the past two decades. In this article, we discuss these achievements and outline a vision for the future of maternal, newborn and child survival in Nepal after the era of the Millennium Development Goals. On the pathway towards quality universal health care services for all, we propose strengthening of health information systems, gradual health system reforms, improvement of existing facility based services, development of integrated service delivery models, improved technical and managerial capacity at district and facility levels. Elimination of all preventable causes of maternal, newborn and child deaths in Nepal should be our collective aspirational goal.</jats:p
Energy Injection Episodes in Gamma Ray Bursts: The Light Curves and Polarization Properties of GRB 021004
Several GRB afterglow light curves deviate strongly from the power law decay
observed in most bursts. We show that these variations can be accounted for by
including refreshed shocks in the standard fireball model previously used to
interpret the overall afterglow behavior. As an example we consider GRB 021004
that exhibited strong light curve variations and has a reasonably well
time-resolved polarimetry. We show that the light curves in the R-band, X-rays
and in the radio can be accounted for by four energy injection episodes in
addition to the initial event. The polarization variations are shown to be a
consequence of the injections.Comment: 4 pages, 2 figures. To appear in ApJ
Energy and momentum of Bianchi Type VI_h Universes
We obtain the energy and momentum of the Bianchi type VI_h universes using
different prescriptions for the energy-momentum complexes in the framework of
general relativity. The energy and momentum of the Bianchi VI_h universe are
found to be zero for the parameter h = -1 of the metric. The vanishing of these
results support the conjecture of Tryon that Universe must have a zero net
value for all conserved quantities.This also supports the work of Nathan Rosen
with the Robertson-Walker metric. Moreover, it raises an interesting question:
"Why h=-1 case is so special?
Post-correlation radio frequency interference classification methods
We describe and compare several post-correlation radio frequency interference
classification methods. As data sizes of observations grow with new and
improved telescopes, the need for completely automated, robust methods for
radio frequency interference mitigation is pressing. We investigated several
classification methods and find that, for the data sets we used, the most
accurate among them is the SumThreshold method. This is a new method formed
from a combination of existing techniques, including a new way of thresholding.
This iterative method estimates the astronomical signal by carrying out a
surface fit in the time-frequency plane. With a theoretical accuracy of 95%
recognition and an approximately 0.1% false probability rate in simple
simulated cases, the method is in practice as good as the human eye in finding
RFI. In addition it is fast, robust, does not need a data model before it can
be executed and works in almost all configurations with its default parameters.
The method has been compared using simulated data with several other mitigation
techniques, including one based upon the singular value decomposition of the
time-frequency matrix, and has shown better results than the rest.Comment: 14 pages, 12 figures (11 in colour). The software that was used in
the article can be downloaded from http://www.astro.rug.nl/rfi-software
Broad Band Optical Polarimetric Study of IC 1805
We present the BVR broad band polarimetric observations of 51 stars belonging
to the young open cluster IC 1805. Along with the photometric data from the
literature we have modeled and subtracted the foreground dust contribution from
the maximum polarization (P_{max}) and colour excess (E_{B-V}). The mean value
of the P_max for intracluster medium and the foreground are found to be 5.008
+/-0.005 % and 4.865 +/-0.022 % respectively. Moreover, the mean value of the
wavelength of maximum polarization (lambda_{max}) for intracluster medium is
0.541 +/- 0.003 micro m, which is quite similar as the general interstellar
medium (ISM). The resulting intracluster dust component is found to have
negligible polarization efficiency as compared to interstellar dust. Some of
the observed stars in IC 1805 have shown the indication of intrinsic
polarization in their measurements.Comment: 8 pages, 7 figures, Accepted for publication in MNRA
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