629 research outputs found
Haunted by Defeat: Imperial Sexualities, Prostitution and the Emergence of Postwar Japan
published_or_final_versio
A search for transit timing variation
Photometric follow-ups of transiting exoplanets (TEPs) may lead to
discoveries of additional, less massive bodies in extrasolar systems. This is
possible by detecting and then analysing variations in transit timing of
transiting exoplanets. In 2009 we launched an international observing campaign,
the aim of which is to detect and characterise signals of transit timing
variation (TTV) in selected TEPs. The programme is realised by collecting data
from 0.6--2.2-m telescopes spread worldwide at different longitudes. We present
our observing strategy and summarise first results for WASP-3b with evidence
for a 15 Earth-mass perturber in an outer 2:1 orbital resonance.Comment: Poster contribution to Detection and Dynamics of Transiting
Exoplanets (Haute Provence Observatory Colloquium, 23-27 August 2010
Thermal evolution and structure models of the transiting super-Earth GJ 1214b
The planet GJ 1214b is the second known super-Earth with a measured mass and
radius. Orbiting a quiet M-star, it receives considerably less mass-loss
driving X-ray and UV radiation than CoRoT-7b, so that the interior may be quite
dissimilar in composition, including the possibility of a large fraction of
water. We model the interior of GJ 1214b assuming a two-layer (envelope+rock
core) structure where the envelope material is either H/He, pure water, or a
mixture of H/He and H2O. Within this framework we perform models of the thermal
evolution and contraction of the planet. We discuss possible compositions that
are consistent with Mp=6.55 ME, Rp=2.678 RE, an age tau=3-10 Gyr, and the
irradiation level of the atmosphere. These conditions require that if water
exists in the interior, it must remain in a fluid state, with important
consequences for magnetic field generation. These conditions also require the
atmosphere to have a deep isothermal region extending down to 80-800 bar,
depending on composition. Our results bolster the suggestion of a
metal-enriched H/He atmosphere for the planet, as we find water-world models
that lack an H/He atmosphere to require an implausibly large water-to-rock
ratio of more than 6:1. We instead favor a H/He/H2O envelope with high water
mass fraction (~0.5-0.85), similar to recent models of the deep envelope of
Uranus and Neptune. Even with these high water mass fractions in the H/He
envelope, generally the bulk composition of the planet can have subsolar
water:rock ratios. Dry, water-enriched, and pure water envelope models differ
to an observationally significant level in their tidal Love numbers k2 of
respectively ~0.018, 0.15, and 0.7.Comment: 11 pages, 6 figures, 1 table, accepted to Ap
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Latanoprost with high precision, piezo-print microdose delivery for IOP lowering: clinical results of the PG21 study of 0.4 ”g daily microdose.
Background:Topical high-precision piezo-print delivery of microdoses of latanoprost achieved significant IOP reduction consistent with the eyedropper effect but with a 75% reduced exposure to drugs and preservatives. Prostaglandin analogs are a mainstay glaucoma therapy. However, conventional eyedroppers deliver 30-50 ”L drops that greatly exceed the physiologic 7-”L ocular tear film capacity. Eyedropper overdosing floods the eye with excess drug compounds and preservatives, resulting in ocular surface toxicity, periorbitopathy, and other well-characterized ocular side effects. Piezoelectric high-precision microdosing provides targeted delivery that can reduce exposure to both drug and preservatives compared to conventional eyedropper delivery, with the potential to deliver similar biologic effect. Methods:Both eyes (N=60) of 30 healthy volunteers received single 8-”L microdoses of 0.005% latanoprost (0.4 ”g; ”Rx-latanoprost) on the morning of Days 1 and 2 using a high-precision, piezo-print horizontal delivery system. Diurnal IOP was measured before and 2 days after microdosing. Main efficacy outcomes were diurnal IOP change after ”Rx-latanoprost microdosing and accurate microdosing success rates, and the primary safety outcome was adverse event (AE) incidence. Results:”Rx-latanoprost reduced baseline IOP by 26% and 30% at 1 and 2 days postadministration, respectively. Successful topical dosing was achieved in 100% of technician-assisted deliveries. All patients successfully self-administered microdoses after receiving training. Microdose administration was well tolerated and did not result in any AEs. Conclusion:Microdosing of 0.4 ”g of ”Rx-latanoprost achieved significant IOP reduction. Lower ocular exposure with topical prostaglandin analog microdosing can enable new therapeutic opportunities for optimizing glaucoma treatment. Microdosing may also be beneficial in reducing ocular side effects associated with excessive drug product and preservatives often used to treat chronic ocular diseases such as glaucoma
The Effects Of An Intervention Program On Psychosocial Factors And Consequences During The COVIDâ19 Pandemic In A Chilean Technology Services Company: A Quasiexperimental Study
Background and Aims: During the COVIDâ19 pandemic, mental health became a relevant factor in people's performance within organizations. The aim of this study was to analyze the effects of an organizational intervention program on the psychosocial factors of demands, resources, and the consequences of psychosocial risks in a technology services company during the COVIDâ19 pandemic. Methods: A quasiexperimental study was carried out with 105 employees who took part in an 8âweek intervention program divided into two large stages. Preâ and postmeasurements were collected using the UNIPSICO Questionnaire, considering its factors of demands, resources, and consequences of psychosocial risks. The Spanish Burnout Inventory (SBI) was also included. Results: The results showed significant improvements in the perception of the following psychosocial demand factors: Role conflict (p < 0.001), Role ambiguity, workload, interpersonal conflicts (p < 0.05). In the resource factors: autonomy, work social support, feedback (p < 0.001) Resources at work, transformational leadership, and selfâefficacy (p < 0.05). In addition, all the consequences of psychosocial risks have improvements: Indolence, emotional exhaustion, and job satisfaction (p < 0.001), Burnout syndrome, enthusiasm toward the job, and psychosomatic problems (p < 0.05), except the Guilt dimension of the SBI. Conclusion: We can conclude that the program was effective and that the study limitations should be improved in future studies
Towards the Rosetta Stone of planet formation
Transiting exoplanets (TEPs) observed just about 10 Myrs after formation of
their host systems may serve as the Rosetta Stone for planet formation
theories. They would give strong constraints on several aspects of planet
formation, e.g. time-scales (planet formation would then be possible within 10
Myrs), the radius of the planet could indicate whether planets form by
gravitational collapse (being larger when young) or accretion growth (being
smaller when young). We present a survey, the main goal of which is to find and
then characterise TEPs in very young open clusters.Comment: Poster contribution to Detection and Dynamics of Transiting
Exoplanets (Haute Provence Observatory Colloquium, 23-27 August 2010
Rethinking Transnational Activism through Regional Perspectives: Reflections, Literatures and Cases
Copyright \ua9 The Author(s), 2024. Published by Cambridge University Press on behalf of the Royal Historical Society. This collectively authored article argues for a regional turn in the historical study of transnational activism. By considering not only pan-regional movements but also examples of borderland contexts, transregional connections and diasporic understandings of \u27region\u27, our discussion identifies fresh possibilities for investigating the evolution and functioning of transnational activism. Based on a Royal Historical Society-funded workshop held at and supported by Northumbria University, the article brings together insights from diverse locations and arenas of contestation. The first part considers literatures on three macro-regional settings - South Asia, Western Europe and Latin America - to illustrate the importance of distinctive regional contexts and constructs in shaping transnational activism and its goals. The second part turns to case studies of transnational activism in and beyond Eastern Europe, West Africa, the Caribbean and East Asia. In doing so, it explores very different notions of the regional to identify how transnational activism has both shaped and been shaped by these ideas. Taken together, the two parts highlight the role of regional identities and projects in challenging inequalities and external domination. Our analysis and examples indicate the possibilities of a regionally rooted approach for writing histories of transnational activism
Interior structure models of GJ 436b
GJ 436b is the first extrasolar planet discovered that resembles Neptune in
mass and radius. The particularly interesting property of Neptune-sized planets
is that their mass Mp and radius Rp are close to theoretical M-R relations of
water planets. Given Mp, Rp, and equilibrium temperature, however, various
internal compositions are possible. A broad set of interior structure models is
presented here that illustrates the dependence of internal composition and
possible phases of water occurring in presumably water-rich planets, such as GJ
436b on the uncertainty in atmospheric temperature profile and mean density. We
show how the set of solutions can be narrowed down if theoretical constraints
from formation and model atmospheres are applied or potentially observational
constraints for the atmospheric metallicity Z1 and the tidal Love number k2. We
model the interior by assuming either three layers (hydrogen-helium envelope,
water layer, rock core) or two layers (H/He/H2O envelope, rocky core). For
water, we use the equation of state H2O-REOS based on FT-DFT-MD simulations.
Some admixture of H/He appears mandatory for explaining the measured radius.
For the warmest considered models, the H/He mass fraction can reduce to 10^-3,
still extending over ~0.7 REarth. If water occurs, it will be essentially in
the plasma phase or in the superionic phase, but not in an ice phase.
Metal-free envelope models have 0.02<k2<0.2, and the core mass cannot be
determined from a measurement of k2. In contrast, models with 0.3<k2<0.82
require high metallicities Z1<0.89 in the outer envelope. The uncertainty in
core mass decreases to 0.4 Mp, if k2>0.3, and further to 0.2 Mp, if k2>0.5, and
core mass and Z1 become sensitive functions of k2. To further narrow the set of
solutions, a proper treatment of the atmosphere and the evolution is necessary.Comment: 9 pages, accepted to A&
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