425 research outputs found
Variola minor in coalfield areas of England and Wales, 1921–34: geographical determinants of a national smallpox epidemic that spread out of effective control
This paper uses techniques of binary logistic regression to identify the spatial determinants of the last national epidemic of smallpox to spread in England and Wales, the variola minor epidemic of 1921–34. Adjusting for age and county-level variations in vaccination coverage in infancy, the analysis identifies a dose-response gradient with increasing odds of elevated smallpox rates in local government areas with (i) medium (odds ratio [OR] = 5.32, 95% Confidence Interval [95% CI] 1.96–14.41) and high (OR = 11.32, 95% CI 4.20–31.59) coal mining occupation rates and (ii) medium (OR = 16.74, 95% CI 2.24–125.21) and high (OR = 63.43, 95% CI 7.82–497.21) levels of residential density. The results imply that the spatial transmission of variola virus was facilitated by the close spatial packing of individuals, with a heightened transmission risk in coal mining areas of the country. A syndemic interaction between common respiratory conditions arising from exposure to coal dust and smallpox virus transmission is postulated to have contributed to the findings. We suggest that further studies of the geographical intersection of coal mining and acute infections that are transmitted via respiratory secretions are warranted
Beyond academia – interrogating research impact in the Research Excellence Framework
Big changes to the way in which research funding is allocated to UK universities were brought
about in the Research Excellence Framework (REF), overseen by the Higher Education
Funding Council, England. Replacing the earlier Research Assessment Exercise, the purpose of
the REF was to assess the quality and reach of research in UK universities – and allocate
funding accordingly. For the first time, this included an assessment of research ‘impact’,
accounting for 20% of the funding allocation. In this article we use a text mining technique to
investigate the interpretations of impact put forward via impact case studies in the REF process.
We find that institutions have developed a diverse interpretation of impact, ranging from
commercial applications to public and cultural engagement activities. These interpretations of
impact vary from discipline to discipline and between institutions, with more broad-based
institutions depicting a greater variety of impacts. Comparing the interpretations with the score
given by REF, we found no evidence of one particular interpretation being more highly rewarded
than another. Importantly, we also found a positive correlation between impact score and
[overall research] quality score, suggesting that impact is not being achieved at the expense of
research excellence
Visual function before and after the removal of bilateral congenital cataracts in adulthood
AbstractSubject Peter Doyle (PD) had congenital bilateral cataracts removed at the age of 43. Pre-operatively PD's visual acuity was 20/80, with a resolution limit around 15 cpd, and he experienced monocular diplopia with high contrast stimuli. Post-operatively PD's visual acuity improved to approximately 20/40, with a resolution limit around 25 cpd. Using a variety of pre- and post-operative tests we have documented a wide range of neural adaptations to his limited and distorted visual input, and have found a limited amount of post-operative adaptation to his newly improved visual input. These results show that the human visual system is capable of significant adaptation to the particular optical input that is experienced
UCL Department of Science and Technology Studies submission of evidence to the House of Commons Science and Technology Select Committee inquiry into science communication
Short total synthesis of ajoene, (E ,Z )‐4,5,9‐Trithiadodeca‐1,6,11‐triene 9‐oxide, in batch and (E ,Z )‐4,5,9‐Trithiadodeca‐1,7,11‐triene in continuous flow
A short total synthesis of ajoene, (E,Z )‐4,5,9‐trithiadodeca‐1,6,11‐triene 9‐oxide, has been achieved over six steps. In addition, a continuous flow synthesis under mild reaction conditions to (E,Z )‐4,5,9‐trithiadodeca‐1,7,11‐triene is described starting from simple and easily accessible starting materials. Over four steps including propargylation, radical addition of thioacetate, deprotection, and disulfide formation/ allylation, the target product can be obtained at a rate of 0.26 g h−1 in an overall yield of 12 %
Franck-Condon Factors and Radiative Lifetime of the A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} Transition of Ytterbium Monoflouride, YbF
The fluorescence spectrum resulting from laser excitation of the
A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} (0,0) band of ytterbium monofluoride, YbF, has
been recorded and analyzed to determine the Franck-Condon factors. The measured
values are compared with those predicted from Rydberg-Klein-Rees (RKR)
potential energy curves. From the fluorescence decay curve the radiative
lifetime of the A^{2}\Pi_{1/2} state is measured to be 28\pm2 ns, and the
corresponding transition dipole moment is 4.39\pm0.16 D. The implications for
laser cooling YbF are discussed.Comment: 5 pages, 5 figure
<b>Simulating the atmospheric CO2 concentration across the heterogeneous landscape of Denmark using a coupled atmosphere–biosphere mesoscale model system</b><b/>
Although coastal regions only amount to 7 % of the global oceans, their
contribution to the global oceanic air–sea CO2 exchange is
proportionally larger, with fluxes in some estuaries being similar in
magnitude to terrestrial surface fluxes of CO2.
Across a heterogeneous surface consisting of a coastal marginal sea with
estuarine properties and varied land mosaics, the surface fluxes of
CO2 from both marine areas and terrestrial surfaces were investigated
in this study together with their impact in atmospheric CO2
concentrations by the usage of a high-resolution modelling framework. The
simulated terrestrial fluxes across the study region of Denmark experienced
an east–west gradient corresponding to the distribution of the land cover
classification, their biological activity and the urbanised areas. Annually,
the Danish terrestrial surface had an uptake of approximately
−7000 GgC yr−1. While the marine fluxes from the North Sea and the
Danish inner waters were smaller annually, with about −1800 and
1300 GgC yr−1, their sizes are comparable to annual terrestrial fluxes
from individual land cover classifications in the study region and hence are not
negligible. The contribution of terrestrial surfaces fluxes was easily
detectable in both simulated and measured concentrations of atmospheric
CO2 at the only tall tower site in the study region. Although, the
tower is positioned next to Roskilde Fjord, the local marine impact was not
distinguishable in the simulated concentrations. But the regional impact from
the Danish inner waters and the Baltic Sea increased the atmospheric
concentration by up to 0.5 ppm during the winter months.</p
Space-time defects and teleparallelism
We consider the class of space-time defects investigated by Puntigam and
Soleng. These defects describe space-time dislocations and disclinations
(cosmic strings), and are in close correspondence to the actual defects that
arise in crystals and metals. It is known that in such materials dislocations
and disclinations require a small and large amount of energy, respectively, to
be created. The present analysis is carried out in the context of the
teleparallel equivalent of general relativity (TEGR). We evaluate the
gravitational energy of these space-time defects in the framework of the TEGR
and find that there is an analogy between defects in space-time and in
continuum material systems: the total gravitational energy of space-time
dislocations and disclinations (considered as idealized defects) is zero and
infinit, respectively.Comment: 22 pages, no figures, to appear in the Class. Quantum Gravit
Atmospheric CO2 inversion reveals the Amazon as a minor carbon source caused by fire emissions, with forest uptake offsetting about half of these emissions
Finite Volume Kolmogorov-Johnson-Mehl-Avrami Theory
We study Kolmogorov-Johnson-Mehl-Avrami (KJMA) theory of phase conversion in
finite volumes. For the conversion time we find the relationship . Here is the space dimension, the nucleation time in the volume , and a scaling function.
Its dimensionless argument is , where
is an expansion time, defined to be proportional to the
diameter of the volume divided by expansion speed. We calculate in
one, two and three dimensions. The often considered limits of phase conversion
via either nucleation or spinodal decomposition are found to be volume-size
dependent concepts, governed by simple power laws for .Comment: 4 pages, 4 figures. Additions after referee reports: Scaling of the
variable q is proven. Additional references are adde
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