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The relationship of drug reimbursement with the price and the quality of pharmaceutical innovations
This paper studies the strategic interaction between pharmaceutical firms' pricing decisions and government agencies' reimbursement decisions which discriminate between patients by giving reimbursement rights to patients for whom the drug is most effective. We show that if the reimbursement decision preceeds the pricing decision, the agency only reimburses some patients if the private and public health benefits from the new drug diverge. That is, when (i) there are large externalities of consuming the drug and (ii) the difference in costs between the new drug and the alternative treatment is large. Alternatively, if the firm can commit to a price in advance of the reimbursement decision, we identify a strategic effect which implies that by committing to a high price ex ante, the firm can force a listing outcome and make the agency more willing to reimburse than in the absence of commitment
The globular cluster system of the nearest Seyfert II galaxy Circinus
Context. The globular cluster (GC) system of Circinus galaxy has not been
probed previously partly because of the location of the galaxy at - 3.8
Galactic latitude which suffers severely from interstellar extinction, stellar
crowding, and Galactic foreground contamination. However, the deep
near-infrared (NIR) photometry by the VISTA Variables in the Via L\'actea
Extended Survey (VVVX) in combination with the precise astrometry of Gaia EDR3
allow us to map GCs in this region.
Aims. Our long-term goal is to study and characterise the distributions of
GCs and Ultra-compact dwarfs of Circinus galaxy which is the nearest Seyfert II
galaxy. Here we conduct the first pilot search for GCs in this galaxy.
Methods. We use NIR VVVX photometry in combination with Gaia EDR3 astrometric
features such as astrometric excess noise and BP/RP excess factor to build the
first homogeneous catalogue of GCs in Circinus galaxy. A robust combination of
selection criteria allows us to effectively clean interlopers from our sample.
Results. We report the detection of 70 GC candidates in this galaxy at
a 3 confidence level. They show a bimodal colour distribution with the
blue peak at (G-Ks) = 0.9850.127 mag with a dispersion of
0.2110.091 mag and the red peak at (G-Ks) = 1.6250.177 mag with a
dispersion of 0.4820.114 mag. A GC specific frequency (S) of
1.30.2 was derived for the galaxy, and we estimated a total population of
12040 GCs. Based on the projected radial distribution it appears that
Circinus has a different distribution of GC candidates than MW and M31.
Conclusions. We demonstrate that Circinus galaxy hosts a sizeable number of
cluster candidates. This result is the first leap towards understanding the
evolution of old stellar clusters in this galaxy.Comment: 15 pages, 12 figure
LimberJack.jl: auto-differentiable methods for angular power spectra analyses
We present LimberJack.jl, a fully auto-differentiable code for cosmological
analyses of 2 point auto- and cross-correlation measurements from galaxy
clustering, CMB lensing and weak lensing data written in Julia. Using Julia's
auto-differentiation ecosystem, LimberJack.jl can obtain gradients for its
outputs up to an order of magnitude faster than traditional finite difference
methods. This makes LimberJack.jl greatly synergistic with gradient-based
sampling methods, such as Hamiltonian Monte Carlo, capable of efficiently
exploring parameter spaces with hundreds of dimensions. We first prove
LimberJack.jl's reliability by reanalysing the DES Y1 32-point data. We
then showcase its capabilities by using a O(100) parameters Gaussian Process to
reconstruct the cosmic growth from a combination of DES Y1 galaxy clustering
and weak lensing data, eBOSS QSO's, CMB lensing and redshift-space distortions.
Our Gaussian process reconstruction of the growth factor is statistically
consistent with the CDM Planck 2018 prediction at all redshifts.
Moreover, we show that the addition of RSD data is extremely beneficial to this
type of analysis, reducing the uncertainty in the reconstructed growth factor
by on average across redshift. LimberJack.jl is a fully open-source
project available on Julia's general repository of packages and GitHub.Comment: Prepared for OJA. Fixed minor typos. Comments welcomed
Phase diagram for a Cubic Consistent-Q Interacting Boson Model Hamiltonian: signs of triaxiality
An extension of the Consistent-Q formalism for the Interacting Boson Model
that includes the cubic QxQxQ term is proposed. The potential energy surface
for the cubic quadrupole interaction is explicitly calculated within the
coherent state formalism using the complete chi-dependent expression for the
quadrupole operator. The Q-cubic term is found to depend on the asymmetry
deformation parameter gamma as a linear combination of cos(3gamma) and
cos^2(3\gamma) terms, thereby allowing for triaxiality. The phase diagram of
the model in the large N limit is explored, it is described the order of the
phase transition surfaces that define the phase diagram, and moreover, the
possible nuclear equilibrium shapes are established. It is found that, contrary
to expectations, there is only a very tiny region of triaxiality in the model,
and that the transition from prolate to oblate shapes is so fast that, in most
cases, the onset of triaxiality might go unnoticed.Comment: 18 pages, 19 figure
Characterization of Mycobacterium tuberculosis Beijing isolates from the Mediterranean area
<p>Abstract</p> <p>Background</p> <p>The Beijing lineage of <it>Mycobacterium tuberculosis </it>is causing concern due to its global distribution and its involvement in severe outbreaks. Studies focused on this lineage are mainly restricted to geographical settings where its prevalence is high, whereas those in other areas are scarce. In this study, we analyze Beijing isolates in the Mediterranean area, where this lineage is not prevalent and is mainly associated with immigrant cases.</p> <p>Results</p> <p>Only 1% (N = 26) of the isolates from two population-based studies in Spain corresponded to Beijing strains, most of which were pan-susceptible and from Peruvian and Ecuadorian patients. Restriction fragment length polymorphism typing with the insertion sequence IS<it>6110 </it>identified three small clusters (2-3 cases). Mycobacterial interspersed repetitive unit-variable number tandem repeat typing (MIRU-15) offered low discriminatory power, requiring the introduction of five additional loci. A selection of the Beijing isolates identified in the Spanish sample, together with a sample of Beijing strains from Italy, to broaden the analysis context in the Mediterranean area, were assayed in an infection model with THP-1 cells. A wide range of intracellular growth rates was observed with only two isolates showing an increased intracellular replication, in both cases associated with contained production of TNF-α. No correlation was observed between virulence and the Beijing phylogenetic group, clustered/orphan status, or resistance. The Beijing strain responsible for extensive spread on Gran Canaria Island was also identified in Madrid, but did not lead to secondary cases and did not show high infectivity in the infection model.</p> <p>Conclusions</p> <p>The Beijing lineage in our area is a non-homogeneous family, with only certain highly virulent representatives. The specific characterization of Beijing isolates in different settings could help us to accurately identify the virulent representatives before making general assumptions about this lineage.</p
Pulsating stars in ω Centauri. Near-IR properties and period-luminosity relations
Indexación: Scopus.ω Centauri (NGC 5139) contains many variable stars of different types, including the pulsating type II Cepheids, RR Lyrae and SX Phoenicis stars. We carried out a deep, wide-field, near-infrared (IR) variability survey of ω Cen, using the VISTA telescope. We assembled an unprecedented homogeneous and complete J and KS near-IR catalog of variable stars in the field of ω Cen. In this paper we compare optical and near-IR light curves of RR Lyrae stars, emphasizing the main differences. Moreover, we discuss the ability of near-IR observations to detect SX Phoenicis stars given the fact that the amplitudes are much smaller in these bands compared to the optical. Finally, we consider the case in which all the pulsating stars in the three different variability types follow a single period-luminosity relation in the near-IR bands.https://www.epj-conferences.org/articles/epjconf/pdf/2017/21/epjconf_puls2017_07005.pd
Phase diagram and influence of defects in the double perovskites
The phase diagram of the double perovskites of the type Sr_{2-x} La_x Fe Mo
O_6 is analyzed, with and without disorder due to antisites. In addition to an
homogeneous half metallic ferrimagnetic phase in the absence of doping and
disorder, we find antiferromagnetic phases at large dopings, and other
ferrimagnetic phases with lower saturation magnetization, in the presence of
disorder.Comment: 4 pages, 3 postscript figures, some errata correcte
A colour-excess extinction map of the southern Galactic disc from the VVV and GLIMPSE surveys
An improved high-resolution and deep A Ks foreground dust extinction map is presented for the Galactic disc area within 295◦ ≾ l ≾ 350◦, −1.0◦ ≾ b ≾ +1.0◦. At some longitudes the map reaches up to |b| ~ 2.25◦, for a total of ~148 deg 2. The map was constructed via the Rayleigh–Jeans colour excess (RJCE) technique based on deep near-infrared (NIR) and mid-infrared (MIR) photometry. The new extinction map features a maximum bin size of 1 arcmin, and relies on NIR observations from the Two Micron All-Sky Survey (2MASS) and new data from ESO’s Vista Variables in the Vía Láctea (VVV) survey, in concert with MIR observations from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire. The VVV photometry penetrates ~4 mag fainter than 2MASS, and provides enhanced sampling of the underlying stellar populations in this heavily obscured region. Consequently, the new results supersede existing RJCE maps tied solely to brighter photometry, revealing a systematic underestimation of extinction in prior work that was based on shallower data. The new high-resolution and large-scale extinction map presented here is readily available to the community through a web query interface.Peer reviewe
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