1,010 research outputs found
Detection of Pristine Gas Two Billion Years after the Big Bang
In the current cosmological model, only the three lightest elements were
created in the first few minutes after the Big Bang; all other elements were
produced later in stars. To date, however, heavy elements have been observed in
all astrophysical environments. We report the detection of two gas clouds with
no discernible elements heavier than hydrogen. These systems exhibit the lowest
heavy-element abundance in the early universe and thus are potential fuel for
the most metal poor halo stars. The detection of deuterium in one system at the
level predicted by primordial nucleosynthesis provides a direct confirmation of
the standard cosmological model. The composition of these clouds further
implies that the transport of heavy elements from galaxies to their
surroundings is highly inhomogeneous.Comment: 32 pages, 11 figures, SOM included. To appear in Scienc
Homoeopathy
Homoeopathy is a system of treating patients
using very low dose preparations according
to the principle: "like should be cured with
like". This paper summarises the research evidence
presented in a recent issue of Effective Health
Care on the effectiveness of homoeopathy.
Increasing numbers of patients are seeking
information on complementary medicines from
NHS health professionals. Results of a 1998 survey
of use and expenditure on complementary
medicine in England suggested that 28% of
respondents had either visited a complementary
therapist or had purchased an over the counter
herbal or homoeopathic remedy in the past year.
From this survey it was estimated that there
could be over 470 000 recent users of homoeopathic
remedies in England
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