14,320 research outputs found
Biology and health inequality.
Intriguing parallels between civil servant and nonhuman primate hierarchies suggest that highly stratified societies foster health inequalities. Determining how social differences translate into chronic disease remains a challenge, but neuroendocrine pathways appear to play a role
Social inequalities and cardiovascular disease in South Asians
The epidemiological transition provides a temporal framework for thinking about the decline of infectious disease and the rise in cardiovascular and other chronic diseases.1 In Europe, the transition began in the late 19th century with improved sanitation and housing, and controls on food adulteration. Continuing public health measures such as vaccination2 contributed to the steep rise in life expectancy during the 20th century, paralleled by a sharp increase in the prevalence of cardiovascular disease (CVD). In South Asia, the epidemiological transition is taking place against a background of economic globalisation that has greatly increased the size of the urban poor and middle classes, at the same time leaving many millions to continue living on the land at subsistence level. Development is socially and regionally uneven, and so too are the common causes of morbidity and mortality. There is a double burden of disease in the countries of South Asia, characterised by a combination of pandemic infectious disease and high rates of cardiovascular disease. That India’s burden of coronary disease was approaching a similar magnitude to that of the established market economies was demonstrabed as long ago as 1990.
Tensor Product and Permutation Branes on the Torus
We consider B-type D-branes in the Gepner model consisting of two minimal
models at k=2. This Gepner model is mirror to a torus theory. We establish the
dictionary identifying the B-type D-branes of the Gepner model with A-type
Neumann and Dirichlet branes on the torus.Comment: 26 page
Neutrino telescope modelling of Lorentz invariance violation in oscillations of atmospheric neutrinos
One possible feature of quantum gravity may be the violation of Lorentz invariance. In this paper, we consider one particular manifestation of the violation of Lorentz invariance, namely modified dispersion relations for massive neutrinos. We show how such modified dispersion relations may affect atmospheric neutrino oscillations. We then consider how neutrino telescopes, such as ANTARES, may be able to place bounds on the magnitude of this type of Lorentz invariance violation
An independent distance estimate to the AGB star R Sculptoris
For the carbon AGB star R Sculptoris, the uncertain distance significantly
affects the interpretation of observations regarding the evolution of the
stellar mass loss during and after the most recent thermal pulse. We aim to
provide a new, independent measurement of the distance to R Sculptoris,
reducing the absolute uncertainty of the distance estimate to this source. R
Scl is a semi-regular pulsating star, surrounded by a thin shell of dust and
gas created during a thermal pulse approximately 2000 years ago. The stellar
light is scattered by the dust particles in the shell at a radius of 19 arcsec.
The variation in the stellar light affects the amount of dust-scattered light
with the same period and amplitude ratio, but with a phase lag that depends on
the absolute size of the shell. We measured this phase lag by observing the
star R Scl and the dust-scattered stellar light from the shell at five epochs
between June - December 2017. By observing in polarised light, we imaged the
shell in the plane of the sky, removing any uncertainty due to geometrical
effects. The phase lag gives the absolute size of the shell, and together with
the angular size of the shell directly gives the absolute distance to R
Sculptoris. We measured a phase lag between the stellar variations and the
variation in the shell of 40.0 +/- 4.0 days. The angular size of the shell is
measured to be 19.1 arcsec +/- 0.7 arcsec. Combined, this gives an absolute
distance to R Sculptoris of 361 +/- 44 pc. We independently determined the
absolute distance to R Scl with an uncertainty of 12%. The estimated distance
is consistent with previous estimates, but is one of the most accurate
distances to the source to date. In the future, using the variations in
polarised, dust-scattered stellar light, may offer an independent possibility
to measure reliable distances to AGB stars.Comment: accepted by A&A, 8 pages, 8 figure
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