1,688 research outputs found
Include medical ethics in the Research Excellence Framework
The Research Excellence Framework of the Higher Education
Funding Council for England is taking place in 2013, its three
key elements being outputs (65% of the profile), impact (20%),
and “quality of the research environment” (15%). Impact will
be assessed using case studies that “may include any social,
economic or cultural impact or benefit beyond academia that
has taken place during the assessment period.”1
Medical ethics in the UK still does not have its own cognate
assessment panel—for example, bioethics or applied
ethics—unlike in, for example, Australia. Several researchers
in medical ethics have reported to the Institute of Medical Ethics
that during the internal preliminary stage of the Research
Excellence Framework several medical schools have decided
to include only research that entails empirical data gathering.
Thus, conceptual papers and ethical analysis will be excluded.
The arbitrary exclusion of reasoned discussion of medical ethics
issues as a proper subject for medical research unless it is based
on empirical data gathering is conceptually mistaken. “Empirical
ethics” is, of course, a legitimate component of medical ethics
research, but to act as though it is the only legitimate component
suggests, at best, a partial understanding of the nature of ethics
in general and medical ethics in particular. It also mistakenly
places medicine firmly on only one side of the
science/humanities “two cultures” divide instead of in its rightful
place bridging the divide.
Given the emphasis by the General Medical Council on medical
ethics in properly preparing “tomorrow’s doctors,” we urge
medical schools to find a way of using the upcoming Research
Excellence Framework to highlight the expertise residing in
their ethicist colleagues. We are confident that appropriate
assessment will reveal work of high quality that can be shown
to have social and cultural impact and benefit beyond academia,
as required by the framework
Influence du pastoralisme sur les populations acridiennes dans le massif du Siroua (Maroc)
Un foyer de grégarisation de #Dociostaurus maroccanus (Thunb.) a été étudié au cours de cinq missions annuelles (1988-1993). Le site d'étude est un pâturage d'altitude dans l'Anti-Atlas (2300 m) où les troupeaux estivent. Sur les 2850 ha de pâturages à #Poa bulbosa le nombre de moutons et de chèvres a été estimé à 7200 têtes (une tête pour 0,4 ha). Les acridiens (18 espèces) et leurs prédateurs (14 espèces d'insectes et oiseaux) sont cantonnés autour d'une prairie de fauche et des cultures irriguées (55 ha). Le site de ponte du criquet marocain est sur un parc à moutons de 2 hectares. La densité moyenne d'oothèques est de 77/m2, dont 37 % sont détruites par des larves de coléoptères (méloïdes) et des larves de diptères. #Falco naumanni Fleicher et #Pyrrhocorax pyrrhocorax docilis Gm. sont les prédateurs de criquets, importants sur le site. Les craves à bec rouge ont été observés déterrant les oothèques pour les manger. Il est connu que les moutons créent les conditions favorables à la grégarisation du criquet marocain. Nous montrons que le strict calendrier des activités pastorales influence aussi la dynamique des populations acridiennes : les éclosions ont lieu en mai dans un milieu non perturbé par les moutons et à l'abri des prédateurs jusqu'à la fenaison. La transhumance le 28 juillet, en pleine saison de ponte, modifie l'espace et les ressources trophiques disponibles. (Résumé d'auteur
WASP-50b: a hot Jupiter transiting a moderately active solar-type star
We report the discovery by the WASP transit survey of a giant planet in a
close orbit (0.0295+-0.0009 AU) around a moderately bright (V=11.6, K=10) G9
dwarf (0.89+-0.08 M_sun, 0.84+-0.03 R_sun) in the Southern constellation
Eridanus. Thanks to high-precision follow-up photometry and spectroscopy
obtained by the telescopes TRAPPIST and Euler, the mass and size of this
planet, WASP-50b, are well constrained to 1.47+-0.09 M_jup and 1.15+-0.05
R_jup, respectively. The transit ephemeris is 2455558.6120 (+-0.0002) + N x
1.955096 (+-0.000005) HJD_UTC. The size of the planet is consistent with basic
models of irradiated giant planets. The chromospheric activity (log R'_HK =
-4.67) and rotational period (P_rot = 16.3+-0.5 days) of the host star suggest
an age of 0.8+-0.4 Gy that is discrepant with a stellar-evolution estimate
based on the measured stellar parameters (rho_star = 1.48+-0.10 rho_sun, Teff =
5400+-100 K, [Fe/H]= -0.12+-0.08) which favours an age of 7+-3.5 Gy. This
discrepancy could be explained by the tidal and magnetic influence of the
planet on the star, in good agreement with the observations that stars hosting
hot Jupiters tend to show faster rotation and magnetic activity (Pont 2009;
Hartman 2010). We measure a stellar inclination of 84 (-31,+6) deg,
disfavouring a high stellar obliquity. Thanks to its large irradiation and the
relatively small size of its host star, WASP-50b is a good target for
occultation spectrophotometry, making it able to constrain the relationship
between hot Jupiters' atmospheric thermal profiles and the chromospheric
activity of their host stars proposed by Knutson et al. (2010).Comment: 9 pages, 8 figures. Accepted for publication in Astronomy &
Astrophysic
The Spitzer search for the transits of HARPS low-mass planets - II. Null results for 19 planets
Short-period super-Earths and Neptunes are now known to be very frequent
around solar-type stars. Improving our understanding of these mysterious
planets requires the detection of a significant sample of objects suitable for
detailed characterization. Searching for the transits of the low-mass planets
detected by Doppler surveys is a straightforward way to achieve this goal.
Indeed, Doppler surveys target the most nearby main-sequence stars, they
regularly detect close-in low-mass planets with significant transit
probability, and their radial velocity data constrain strongly the ephemeris of
possible transits. In this context, we initiated in 2010 an ambitious Spitzer
multi-Cycle transit search project that targeted 25 low-mass planets detected
by radial velocity, focusing mainly on the shortest-period planets detected by
the HARPS spectrograph. We report here null results for 19 targets of the
project. For 16 planets out of 19, a transiting configuration is strongly
disfavored or firmly rejected by our data for most planetary compositions. We
derive a posterior probability of 83% that none of the probed 19 planets
transits (for a prior probability of 22%), which still leaves a significant
probability of 17% that at least one of them does transit. Globally, our
Spitzer project revealed or confirmed transits for three of its 25 targeted
planets, and discarded or disfavored the transiting nature of 20 of them. Our
light curves demonstrate for Warm Spitzer excellent photometric precisions: for
14 targets out of 19, we were able to reach standard deviations that were
better than 50ppm per 30 min intervals. Combined with its Earth-trailing orbit,
which makes it capable of pointing any star in the sky and to monitor it
continuously for days, this work confirms Spitzer as an optimal instrument to
detect sub-mmag-deep transits on the bright nearby stars targeted by Doppler
surveys.Comment: Accepted for publication in Astronomy and Astrophysics. 23 pages, 21
figure
Ground-based monitoring of comet 67P/Churyumov-Gerasimenko gas activity throughout the <i>Rosetta</i> mission
Simultaneously to the ESA Rosetta mission, a world-wide ground-based campaign provided measurements of the large scale activity of comet 67P/Churyumov-Gerasimenko through measurement of optically active gas species and imaging of the overall dust coma. We present more than two years of observations performed with the FORS2 low resolution spectrograph at the VLT, TRAPPIST, and ACAM at the WHT. We focus on the evolution of the CN production, as a tracer of the comet activity. We find that it is asymmetric with respect to perihelion and different from that of the dust. The CN emission is detected for the first time at 1.34 au pre-perihelion and production rates then increase steeply to peak about two weeks after perihelion at (1.00±0.10) ×1025 molecules s−1, while the post-perihelion decrease is more shallow. The evolution of the comet activity is strongly influenced by seasonal effects, with enhanced CN production when the Southern hemisphere is illuminated
Lupus-TR-3b: A Low-Mass Transiting Hot Jupiter in the Galactic Plane?
We present a strong case for a transiting Hot Jupiter planet identified
during a single-field transit survey towards the Lupus Galactic plane. The
object, Lupus-TR-3b, transits a V=17.4 K1V host star every 3.91405d.
Spectroscopy and stellar colors indicate a host star with effective temperature
5000 +/- 150K, with a stellar mass and radius of 0.87 +/- 0.04M_sun and 0.82
+/- 0.05R_sun, respectively. Limb-darkened transit fitting yields a companion
radius of 0.89 +/- 0.07R_J and an orbital inclination of 88.3 +1.3/-0.8 deg.
Magellan 6.5m MIKE radial velocity measurements reveal a 2.4 sigma K=114 +/-
25m/s sinusoidal variation in phase with the transit ephemeris. The resulting
mass is 0.81 +/- 0.18M_J and density 1.4 +/- 0.4g/cm^3. Y-band PANIC image
deconvolution reveal a V>=21 red neighbor 0.4'' away which, although highly
unlikely, we cannot conclusively rule out as a blended binary with current
data. However, blend simulations show that only the most unusual binary system
can reproduce our observations. This object is very likely a planet, detected
from a highly efficient observational strategy. Lupus-TR-3b constitutes the
faintest ground-based detection to date, and one of the lowest mass Hot
Jupiters known.Comment: 4 pages, 4 figures, accepted for publication in ApJ
The GROUSE project II: Detection of the Ks-band secondary eclipse of exoplanet HAT-P-1b
Context: Only recently it has become possible to measure the thermal emission
from hot-Jupiters at near-Infrared wavelengths using ground-based telescopes,
by secondary eclipse observations. This allows the planet flux to be probed
around the peak of its spectral energy distribution, which is vital for the
understanding of its energy budget. Aims: The aim of the reported work is to
measure the eclipse depth of the planet HAT-P-1b at 2.2micron. This planet is
an interesting case, since the amount of stellar irradiation it receives falls
in between that of the two best studied systems (HD209458 and HD189733), and it
has been suggested to have a weak thermal inversion layer. Methods: We have
used the LIRIS instrument on the William Herschel Telescope (WHT) to observe
the secondary eclipse of HATP-1b in the Ks-band, as part of our Ground-based
secondary eclipse (GROUSE) project. The observations were done in staring mode,
while significantly defocusing the telescope to avoid saturation on the K=8.4
star. With an average cadence of 2.5 seconds, we collected 6520 frames during
one night. Results: The eclipse is detected at the 4sigma level, the measured
depth being 0.109+/-0.025%. The uncertainties are dominated by residual
systematic effects, as estimated from different reduction/analysis procedures.
The measured depth corresponds to a brightness temperature of 2136+150-170K.
This brightness temperature is significantly higher than those derived from
longer wavelengths, making it difficult to fit all available data points with a
plausible atmospheric model. However, it may be that we underestimate the true
uncertainties of our measurements, since it is notoriously difficult to assign
precise statistical significance to a result when systematic effects are
important.Comment: 7 pages, 10 figures, Accepted for publication in A&
WASP-42 b and WASP-49 b: two new transiting sub-Jupiters
We report the discovery of two new transiting planets from the WASP survey.
WASP-42 b is a 0.500 +/- 0.035 M_jup planet orbiting a K1 star at a separation
of 0.0548 +/- 0.0017 AU with a period of 4.9816872 +/- 7.3 x 10^-6 days. The
radius of WASP-42 b is 1.080 +/- 0.057 R_jup while its equilibrium temperature
is T_eq = 995 +/- 34 K. We detect some evidence for a small but non-zero
eccentricity of e=0.060 +/- 0.013. WASP-49 b is a 0.378 +/- 0.027 M_jup planet
around an old G6 star. It has a period of 2.7817387 +/- 5.6 x 10^-6 days and a
separation of 0.0379 +/- 0.0011 AU. This planet is slightly bloated, having a
radius of 1.115 +/- 0.047 R_jup and an equilibrium temperature of T_eq = 1369
+/- 39 K. Both planets have been followed up photometrically, and in total we
have obtained 5 full and one partial transit light curves of WASP-42 and 4 full
and one partial light curves of WASP-49 using the Euler-Swiss, TRAPPIST and
Faulkes South telescopes
Structure and evolution of super-Earth to super-Jupiter exoplanets: I. heavy element enrichment in the interior
We examine the uncertainties in current planetary models and we quantify
their impact on the planet cooling histories and mass-radius relationships.
These uncertainties include (i) the differences between the various equations
of state used to characterize the heavy material thermodynamical properties,
(ii) the distribution of heavy elements within planetary interiors, (iii) their
chemical composition and (iv) their thermal contribution to the planet
evolution. Our models, which include a gaseous H/He envelope, are compared with
models of solid, gasless Earth-like planets in order to examine the impact of a
gaseous envelope on the cooling and the resulting radius. We find that for a
fraction of heavy material larger than 20% of the planet mass, the distribution
of the heavy elements in the planet's interior affects substantially the
evolution and thus the radius at a given age. For planets with large core mass
fractions (\simgr 50%), such as the Neptune-mass transiting planet GJ436b,
the contribution of the gravitational and thermal energy from the core to the
planet cooling history is not negligible, yielding a 10% effect on the
radius after 1 Gyr. We show that the present mass and radius determinations of
the massive planet Hat-P-2b require at least 200 \mearth of heavy material in
the interior, at the edge of what is currently predicted by the core-accretion
model for planet formation. We show that if planets as massive as 25
\mjup can form, as predicted by improved core-accretion models, deuterium is
able to burn in the H/He layers above the core, even for core masses as large
as 100 \mearth. We provide extensive grids of planetary evolution
models from 10 \mearth to 10 M, with various fractions of heavy
elements.Comment: 20 pages, 12 figures. Accepted for publication in Astronomy and
Astrophysic
Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1
One aim of modern astronomy is to detect temperate, Earth-like exoplanets that are well suited for atmospheric characterization. Recently, three Earth-sized planets were detected that transit (that is, pass in front of) a star with a mass just eight per cent that of the Sun, located 12 parsecs away. The transiting configuration of these planets, combined with the Jupiter-like size of their host star—named TRAPPIST-1—makes possible in-depth studies of their atmospheric properties with present-day and future astronomical facilities. Here we report the results of a photometric monitoring campaign of that star from the ground and space. Our observations reveal that at least seven planets with sizes and masses similar to those of Earth revolve around TRAPPIST-1. The six inner planets form a near-resonant chain, such that their orbital periods (1.51, 2.42, 4.04, 6.06, 9.1 and 12.35 days) are near-ratios of small integers. This architecture suggests that the planets formed farther from the star and migrated inwards. Moreover, the seven planets have equilibrium temperatures low enough to make possible the presence of liquid water on their surfaces
- …
