32 research outputs found
de Sitter limit of inflation and nonlinear perturbation theory
We study the fourth order action of the comoving curvature perturbation in an
inflationary universe in order to understand more systematically the de Sitter
limit in nonlinear cosmological perturbation theory. We derive the action of
the curvature perturbation to fourth order in the comoving gauge, and show that
it vanishes sufficiently fast in the de Sitter limit. By studying the de Sitter
limit, we then extrapolate to the n'th order action of the comoving curvature
perturbation and discuss the slow-roll order of the n-point correlation
function.Comment: 14 pages, 1 figure; typos corrected and discussion of tensor modes
adde
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The Velocity Field of the Local Universe From Measurements of Type Ia Supernovae
We present a measurement of the velocity flow of the local universe relative to the CMB rest frame, based on the Jha, Riess & Kirshner (2007) sample of 133 low redshift type Ia supernovae. At a depth of 4500 km s{sup -1} we find a dipole amplitude of 279 {+-} 68 km s{sup -1} in the direction l = 285{sup o} {+-} 18{sup o}, b = -10{sup o} {+-} 15{sup o}, consistent with earlier measurements and with the assumption that the local velocity field is dominated by the Great Attractor region. At a larger depth of 5900 km s{sup -1} we find a shift in the dipole direction towards the Shapley concentration. We also present the first measurement of the quadrupole term in the local velocity flow at these depths. Finally, we have performed detailed studies based on N-body simulations of the expected precision with which the lowest multipoles in the velocity field can be measured out to redshifts of order 0.1. Our mock catalogues are in good agreement with current observations, and demonstrate that our results are robust with respect to assumptions about the influence of local environment on the type Ia supernova rate
Exploring the impact of an evolving war and terror blogosphere on traditional media coverage of conflict
This article analyses the evolution of a war and terror blogosphere between 2001 and 2011. It identifies seven areas where blogs and related online genres could provide
‘alternative’ accounts to traditional media narratives of conflict. The article also assesses the challenges and opportunities of blogs in each area from the perspective of the working journalist in order to deepen our understanding of the changing influence of blogs on traditional media narratives of conflict. Parallel accounts and interpretations of conflict will collaborate and compete in a war and terror blogosphere in the future, but it has been significantly influenced by the adoption of blogging by military actors since 2008. The war and terror blogosphere is no longer a relatively unmonitored online space which is having an impact on both the production of ‘alternative’ accounts of conflict and the incorporation of these accounts into traditional journalism
High-precision photometry by telescope defocussing - VIII.WASP-22, WASP-41,WASP-42 andWASP-55
We present 13 high-precision and four additional light curves of four bright southernhemisphere transiting planetary systems: WASP-22, WASP-41, WASP-42 and WASP-55. In the cases of WASP-42 and WASP-55, these are the first follow-up observations since their discovery papers. We present refined measurements of the physical properties and orbital ephemerides of all four systems. No indications of transit timing variations were seen. All four planets have radii inflated above those expected from theoretical models of gas-giant planets; WASP-55 b is the most discrepant with a mass of 0.63MJup and a radius of 1.34 RJup. WASP-41 shows brightness anomalies during transit due to the planet occulting spots on the stellar surface. Two anomalies observed 3.1 d apart are very likely due to the same spot. We measure its change in position and determine a rotation period for the host star of 18.6 ± 1.5 d, in good agreement with a published measurement from spot-induced brightness modulation, and a sky-projected orbital obliquity of λ = 6 ± 11°. We conclude with a compilation of obliquity measurements from spot-tracking analyses and a discussion of this technique in the study of the orbital configurations of hot Jupiters
VizieR Online Data Catalog: Lucky Imaging photometry of Luhman 16AB (Mancini+, 2015)
Photometric light curves of Luhman 16A and Luhman 16B. (2 data files). <P /
High-precision photometry by telescope defocussing - VIII. WASP-22, WASP-41, WASP-42 and WASP-55
We present 13 high-precision and four additional light curves of four bright southern-hemisphere transiting planetary systems: WASP-22, WASP-41, WASP-42 and WASP-55. In the cases of WASP-42 and WASP-55, these are the first follow-up observations since their discovery papers. We present refined measurements of the physical properties and orbital ephemerides of all four systems. No indications of transit timing variations were seen. All four planets have radii inflated above those expected from theoretical models of gas-giant planets; WASP-55 b is the most discrepant with a mass of 0.63M(Jup) and a radius of 1.34 R-Jup. WASP-41 shows brightness anomalies during transit due to the planet occulting spots on the stellar surface. Two anomalies observed 3.1 d apart are very likely due to the same spot. We measure its change in position and determine a rotation period for the host star of 18.6 +/- 1.5 d, in good agreement with a published measurement from spot-induced brightness modulation, and a sky-projected orbital obliquity of lambda = 6 +/- 11 degrees. We conclude with a compilation of obliquity measurements from spot-tracking analyses and a discussion of this technique in the study of the orbital configurations of hot Jupiters
Adherence to treatment: practice, education and research in Danish community pharmacy
Objective: To describe the practice, education and
research concerning medication adherence in
Danish community pharmacy.
Methods: The authors supplemented their expertise
in the area of medication adherence through their
contacts with other educators and researchers as
well as by conducting searches in the Danish
Pharmacy Practice Evidence Database, which
provides annually updated literature reviews on
intervention research in Danish pharmacy practice.
Results: Practice: Medication adherence is the
focus of and/or is supported by a large number of
services and initiatives used in pharmacy practice
such as governmental funding, IT-supported
medicine administration systems, dose-dispensing
systems, theme years in pharmacies on adherence
and concordance, standards for counselling at the
counter, pharmacist counselling, medication reviews
and inhaler technique assessment. Education: In
Denmark, pharmacy and pharmaconomist students
are extensively trained in the theory and practice of
adherence to therapy.
Pharmacy staff can choose from a variety of
continuing education and post-graduate
programmes which address patient adherence.
Research: Nine ongoing and recently completed
studies are described. Early research in Denmark
comprised primarily smaller, qualitative studies
centred on user perspectives, whereas later
research has shifted the focus towards larger,
quantitative, controlled studies and action-oriented
studies focusing on patient groups with chronic
diseases (such as diabetes, asthma, coronary
vascular diseases).
Conclusions: Our analysis has documented that
Danish pharmaceutical education and research has
focused strongly on adherence to treatment for
more than three decades. Adherence initiatives in
Danish community pharmacies have developed
substantially in the past 5-10 years, and, as pharmacies have prioritised their role in health care
and patient safety, this development can be
expected to continue in future years.Se realizó la evaluación del programa de gestión de
enfermedad para diabetes tipo 2, �SugarCare�. En
comparación con los cuidados normales, este
programa ofrecÃa a los pacientes un seguimiento
más próximo de la glucemia, consejo sobre hábitos
de vida, etc. El estudio SugarCare estuvo
financiado por una beca, opero si se quiere que los
cuidados continúen debe encontrarse otro método
de financiación.
Objetivos: Este estudio pretendió medir las
preferencias de los consumidores por uno de los
dos tipos de cuidados ofrecidos en el estudio
SugarCare, el control/estándar y el servicio
intervención/avanzado; la fuerza de esas
preferencias; y la voluntad de los participantes de
pagar (WTP) por el cuidado preferido.
Métodos: SugarCare era un diseño en grupos
paralelos, control contra intervención, con
mediciones repetidas en tres áreas de New South
Wales (Australia). Los pacientes en el grupo
intervención (cuidados elevados) tenÃan una visita
inicial a la farmacia con seis visitas de seguimiento
durante aproximadamente 9 meses. En esas visitas,
se medÃa la glucemia y se resolvÃan problemas en
de los pacientes. Al final del servicio, se envió un
cuestionario a los participantes control e
intervención y se les pedÃa que lo leyesen y
esperasen una llamada de teléfono a las dos
semanas de recibirlo. Se solicitaban las respuestas
al teléfono y el investigador completaba el
cuestionario. Los datos de WTP se recogieron
utilizando un método de tarjeta de pago
modificado.
Resultados: 44/75 respondentes (59%; 47%-70%
95%CI) expresó preferencias por el escenario B
(cuidados avanzados) mientras que 31/75 (41%;
31%-52% 95CI) prefirió el escenario A (cuidaos
estándar), sin embargo la diferencia no fue
estadÃsticamente significativa. La mediana del WTP
máximo fue de 10 dólares australianos (AUD) para
los cuidados avanzados y de 3,30AUD para los
cuidados estándar (p<0,03). Conclusiones: Mientras que los valores de WTP
expresados eran significativamente más altos para
los cuidados avanzados, no encajaban con el coste
de proporcionar esos cuidados diabéticos. El
análisis de selección discreta tiene la posibilidad de
superar algunas de las dificultades encontradas con
la técnica de evaluación de contingencia utilizada
aquÃ. Se necesitan investigaciones adicionales antes
de que los valores de WTP como estos puedan ser
utilizados con confianza para determinar polÃticas
de financiación
Explaining the luminosity spread in young clusters:proto and pre-main sequence stellar evolution in a molecular cloud environment
Hertzsprung-Russell diagrams of star forming regions show a large luminosity
spread. This is incompatible with well-defined isochrones based on classic
non-accreting protostellar evo- lution models. Protostars do not evolve in
isolation of their environment, but grow through accretion of gas. In addition,
while an age can be defined for a star forming region, the ages of individual
stars in the region will vary. We show how the combined effect of a
protostellar age spread, a consequence of sustained star formation in the
molecular cloud, and time-varying protostellar accretion for individual
protostars can explain the observed luminosity spread. We use a global MHD
simulation including a sub-scale sink particle model of a star forming region
to follow the accretion process of each star. The accretion profiles are used
to compute stellar evolution models for each star, incorporating a model of how
the accretion energy is distributed to the disk, radiated away at the accretion
shock, or incorporated into the outer layers of the protostar. Using a modelled
cluster age of 5 Myr we naturally reproduce the lumi- nosity spread and find
good agreement with observations of the Collinder 69 cluster, and the Orion
Nebular Cluster. It is shown how stars in binary and multiple systems can be
externally forced creating recurrent episodic accretion events. We find that in
a realistic global molecular cloud model massive stars build up mass over
relatively long time-scales. This leads to an important conceptual change
compared to the classic picture of non-accreting stellar evolution segmented in
to low-mass Hayashi tracks and high-mass Henyey tracks.Comment: 20 pages, 16 figures, Updated to match published article in MNRA