bluuebunny/crossref_metadata_2025_split huggingface dataset:
L'impact différencié de la réforme des droits de propriété sur la richesse
Authors: Carter Michael R. , Olinto Pedro 
Published: July 2018

The Wealth-Differentiated Impact of Property Rights Reform
Theory suggests that land titling may positively influence agricultural performances by stimulating both the investment demand and the formal credit supply as well as by speeding the transfer of land from the less to the more productive agents on the land market. This article provides an econometric investigation of these hypotheses, based on panel data collected from a sample of 300 Paraguayan farms households surveyed in 1991 and 1994. This data set makes possible to identify the effect of land title stripped of the effects of farm and farmers characteristics that may be correlated with land tenure status. The first estimation of the gross impact of land title shows significant positive effects on farm productivity. Switching regressions models are used to estimate the joint impact of land title on the supply of credit and the demand for investment. Results support the hypotheses. However, the credit supply effect is found to be more pronounced in the case of large farms whilst the investment demand effect appears lower when farms are credit constrained. Moreover, the analysis of land market transactions suggests that the efficient redistribution effect is impeded by credit constraints.
La politique fiscale agit-elle sur la croissance ?
Authors: Brun Jean-François , Chambas Gérard , Combes Jean-Louis 
Published: July 2018

Is Economie Growth Affected by Taxation Policy ?
Since Barro [1991], there is a growing empirical literature devoted to the determinants of economic growth. This literature fails, however, to take into account the role of taxation. It is important to analyse the effects of taxation when drastic taxation reforms are implemented. In this paper we attempt to evaluate the magnitude of some taxation ratios on economic growth using an international pooled cross-section sample. We find that the global taxation shares of GDP reduce the growth rates and that taxes on trade are the most harmful.
La relation entre invalidité et emploi à Madagascar
Authors: Dumont Jean-Christophe 
Published: July 2018

The Relation between Health and Employment Characteristics for Madagascar
In this article we specify and estimate wage, participation and labor supply equations in which we include health variables. We use data from an household survey which has been held in the Malagasy chief town in 1997 and develop a specific measure of handicap and impairment (ici). Estimations take into account potential selectivity and endogeneity bias. The results reveal the existence of a positive and significant relation between physical capacity and the probability to be employed. Health indicators are also linked to wage rate but not to the number of hours worked.
An Efficient Method for Determining the Chemical Evolution of Gravitationally Collapsing Prestellar Cores
Authors: Priestley F. D. , Viti S. , Williams D. A. 
Published: July 2018

Abstract
We develop analytic approximations to the density evolution of prestellar cores, based on the results of hydrodynamical simulations. We use these approximations as input for a time-dependent gas-grain chemical code to investigate the effects of differing modes of collapse on the molecular abundances in the core. We confirm that our method can provide reasonable agreement with an exact numerical solution of both the hydrodynamics and chemistry while being significantly less computationally expensive, allowing a large grid of models varying multiple input parameters to be run. We present results using this method to illustrate how the chemistry is affected not only by the collapse model adopted but also by the large number of unknown physical and chemical parameters. Models that are initially gravitationally unstable predict similar abundances despite differing densities and collapse timescales, while ambipolar diffusion (AD) produces more extended inner depleted regions that are not seen in observations of prestellar cores. Molecular observations are capable of discriminating between modes of collapse despite the unknown values of various input parameters. We also investigate the evolution of the AD timescale for a range of collapse modes, metallicities, and cosmic-ray ionization rates, finding that it remains comparable to or larger than the collapse timescale during the initial stages for all models we consider, but becomes smaller at later evolutionary stages. This confirms that AD is an important process for diffuse gas but becomes less significant as cores collapse to higher densities.
The Best Planets to Harbor Detectable Exomoons
Authors: Guimarães Ana , Valio Adriana 
Published: July 2018

Abstract
Albeit the discovery of thousands of extrasolar planets, so far no exomoon has been found. This may be due to a lack of dynamical investigation of the best regions around the planets for a satellite to exist. We provide a list of the best candidates of exomoon hosting planets using the Kepler database. The inner and outer stability boundaries of an exomoon orbital semimajor axis were calculated for all planets. The first limit is the minimum distance to the planet such that the object will not disintegrate due to tidal forces, the Roche limit, that depends on the moon density. The outer boundary is the region where an exomoon may exist for a long period of time. Both limits are a function of the planet mass, calculated from its radius inferred from the observed transit depth. Each planet has been tested with the exomoon mass estimated for three values of moon–planet distance, and the moon radius for five different densities (ice, ice–rock, rock, rock–iron, and iron), totalling 15 different combinations. For the planet to be considered a suitable exomoon host, the system has to pass three criteria: (i) the planet–moon distance should be greater than the Roche limit; (ii) the system center-of-mass is within the planet; and (iii) the moon transit depth is greater than twice the light-curve noise (Combined Differential Photometric Precision). After processing all the data, 54 planets were left from the Kepler list with putative “visible” satellites, thus providing the best candidates for an exomoon search.
Spectroscopic Orbits of Subsystems in Multiple Stars. III.
Authors: Tokovinin Andrei 
Published: July 2018

Abstract
Spectroscopic orbits are computed for inner pairs in six nearby hierarchical multiple systems (HIP 35733, 95106/95110, 105441, 105585/105569, 105947, and 109951). Radial velocities and resolved measurements, when available, are used to derive combined sets of outer orbital elements for three systems. Each multiple system is discussed individually. Additionally, HIP 115087 is a simple 7.9-day single-lined binary. Although the minimum companion mass is substellar (in the brown dwarf desert regime), it appears to be a 0.2 solar-mass star in a low-inclination orbit.
Direct Imaging of the HD 35841 Debris Disk: A Polarized Dust Ring from Gemini Planet Imager and an Outer Halo from HST/STIS
Authors: Esposito Thomas M. , Duchêne Gaspard , Kalas Paul , Rice Malena , Choquet Élodie , Ren Bin , Perrin Marshall D. , Chen Christine H. , Arriaga Pauline , Chiang Eugene , Nielsen Eric L. , Graham James R. , Wang Jason J. , Rosa Robert J. De , Follette Katherine B. , Ammons S. Mark , Ansdell Megan , Bailey Vanessa P. , Barman Travis , Bruzzone Juan Sebastián , Bulger Joanna , Chilcote Jeffrey , Cotten Tara , Doyon Rene , Fitzgerald Michael P. , Goodsell Stephen J. , Greenbaum Alexandra Z. , Hibon Pascale , Hung Li-Wei , Ingraham Patrick , Konopacky Quinn , Larkin James E. , Macintosh Bruce , Maire Jérôme , Marchis Franck , Marois Christian , Mazoyer Johan , Metchev Stanimir , Millar-Blanchaer Maxwell A. , Oppenheimer Rebecca , Palmer David , Patience Jennifer , Poyneer Lisa , Pueyo Laurent , Rajan Abhijith , Rameau Julien , Rantakyrö Fredrik T. , Ryan Dominic , Savransky Dmitry , Schneider Adam C. , Sivaramakrishnan Anand , Song Inseok , Soummer Rémi , Thomas Sandrine , Wallace J. Kent , Ward-Duong Kimberly , Wiktorowicz Sloane , Wolff Schuyler 
Published: July 2018

Abstract
We present new high resolution imaging of a light-scattering dust ring and halo around the young star HD 35841. Using spectroscopic and polarimetric data from the Gemini Planet Imager in H-band (1.6 μm), we detect the highly inclined (i = 85°) ring of debris down to a projected separation of ∼12 au (∼0.″12) for the first time. Optical imaging from HST/STIS shows a smooth dust halo extending outward from the ring to >140 au (>1.″4). We measure the ring’s scattering phase function and polarization fraction over scattering angles of 22°–125°, showing a preference for forward scattering and a polarization fraction that peaks at ∼30% near the ansae. Modeling of the scattered-light disk indicates that the ring spans radii of ∼60–220 au, has a vertical thickness similar to that of other resolved dust rings, and contains grains as small as 1.5 μm in diameter. These models also suggest the grains have a low porosity, are more likely to consist of carbon than astrosilicates, and contain significant water ice. The halo has a surface brightness profile consistent with that expected from grains pushed by radiation pressure from the main ring onto highly eccentric but still bound orbits. We also briefly investigate arrangements of a possible inner disk component implied by our spectral energy distribution models, and speculate about the limitations of Mie theory for doing detailed analyses of debris disk dust populations.
Do SN 2002cx-like and SN Ia-CSM Objects Share the Same Origin?
Authors: Meng X. , Podsiadlowski Ph. 
Published: July 2018

Abstract
SN 2002cx-like and SN Ia-CSM objects show similar early spectra and both belong to a young stellar population, suggesting that they could share the same progenitor origin. Adopting the framework of the common-envelope-wind model developed in Meng & Podsiadlowski, we propose that both subclasses of SNe Ia are caused by the explosion of hybrid carbon–oxygen–neon white dwarfs (CONe WDs) in single-degenerate systems, where SNe Ia-CSM explode in systems with a massive common envelope (CE) of ∼1 M
⊙, while SN 2002cx-like events correspond to those events where most of the CE has been lost in a wind. Using binary-population-synthesis calculations, we estimate a number ratio of SNe Ia-CSM to SN 2002cx-like objects between 1/3 and 2/3, consistent with observational constraints, and an overall contribution from hybrid CONe WDs to the total SN Ia population that also matches the observed number from these peculiar objects. Our model predicts a statistical sequence of circumstellar material density from SN Ia-CSM to SN 2002cx-like events and normal SNe Ia, consistent with existing radio constraints. We also find a new subclass of hybrid SNe that share the properties of Type II and Type Ia SNe, consistent with some observed SNe, which do not have a surviving companion. In some cases, these could even produce SNe Ia from apparently single WDs.
Milky Way Cepheid Standards for Measuring Cosmic Distances and Application to Gaia DR2: Implications for the Hubble Constant
Authors: Riess Adam G. , Casertano Stefano , Yuan Wenlong , Macri Lucas , Bucciarelli Beatrice , Lattanzi Mario G. , MacKenty John W. , Bowers J. Bradley , Zheng WeiKang , Filippenko Alexei V. , Huang Caroline , Anderson Richard I. 
Published: July 2018

Abstract
We present Hubble Space Telescope (HST) photometry of a selected sample of 50 long-period, low-extinction Milky Way Cepheids measured on the same WFC3 F555W-, F814W-, and F160W-band photometric system as extragalactic Cepheids in Type Ia supernova host galaxies. These bright Cepheids were observed with the WFC3 spatial scanning mode in the optical and near-infrared to mitigate saturation and reduce pixel-to-pixel calibration errors to reach a mean photometric error of 5 mmag per observation. We use the new Gaia DR2 parallaxes and HST photometry to simultaneously constrain the cosmic distance scale and to measure the DR2 parallax zeropoint offset appropriate for Cepheids. We find the latter to be −46 ± 13 μas or ±6 μas for a fixed distance scale, higher than found from quasars, as expected for these brighter and redder sources. The precision of the distance scale from DR2 has been reduced by a factor of 2.5 because of the need to independently determine the parallax offset. The best-fit distance scale is 1.006 ± 0.033, relative to the scale from Riess et al. with H
0 = 73.24 km s−1 Mpc−1 used to predict the parallaxes photometrically, and is inconsistent with the scale needed to match the Planck 2016 cosmic microwave background data combined with ΛCDM at the 2.9σ confidence level (99.6%). At 96.5% confidence we find that the formal DR2 errors may be underestimated as indicated. We identify additional errors associated with the use of augmented Cepheid samples utilizing ground-based photometry and discuss their likely origins. Including the DR2 parallaxes with all prior distance-ladder data raises the current tension between the late and early universe route to the Hubble constant to 3.8σ (99.99%). With the final expected precision from Gaia, the sample of 50 Cepheids with HST photometry will limit to 0.5% the contribution of the first rung of the distance ladder to the uncertainty in H
0.
Why Post-starburst Galaxies Are Now Quiescent
Authors: French K. Decker , Zabludoff Ann I. , Yoon Ilsang , Shirley Yancy , Yang Yujin , Smercina Adam , Smith J. D. , Narayanan Desika 
Published: July 2018

Abstract
Post-starburst or “E + A” galaxies are rapidly transitioning from star-forming to quiescence. While the current star formation rate (SFR) of post-starbursts is already at the level of early-type galaxies, we recently discovered that many have large CO-traced molecular gas reservoirs consistent with normal star-forming galaxies. These observations raise the question of why these galaxies have such low SFRs. Here we present an ALMA search for the denser gas traced by HCN (1–0) and HCO+ (1–0) in two CO-luminous, quiescent post-starburst galaxies. Intriguingly, we fail to detect either molecule. The upper limits are consistent with the low SFRs and with early-type galaxies. The HCN/CO luminosity ratio upper limits are low compared to star-forming and even many early-type galaxies. This implied low dense gas mass fraction explains the low SFRs relative to the CO-traced molecular gas and suggests that the state of the gas in post-starburst galaxies is unusual, with some mechanism inhibiting its collapse to denser states. We conclude that post-starbursts galaxies are now quiescent because little dense gas is available, in contrast to the significant CO-traced lower density gas reservoirs that still remain.
Modeling the He ii Transverse Proximity Effect: Constraints on Quasar Lifetime and Obscuration
Authors: Schmidt Tobias M. , Hennawi Joseph F. , Worseck Gábor , Davies Frederick B. , Lukić Zarija , Oñorbe Jose 
Published: July 2018

Abstract
The He ii transverse proximity effect—enhanced He ii Lyα transmission in a background sightline caused by the ionizing radiation of a foreground quasar—offers a unique opportunity to probe the emission properties of quasars, in particular the emission geometry (obscuration, beaming) and the quasar lifetime. Building on the foreground quasar survey published in Schmidt et al., we present a detailed model of the He ii transverse proximity effect, specifically designed to include light travel time effects, finite quasar ages, and quasar obscuration. We post-process outputs from a cosmological hydrodynamical simulation with a fluctuating He ii ultraviolet background model, with the added effect of the radiation from a single bright foreground quasar. We vary the age t
age and obscured sky fractions Ωobsc of the foreground quasar, and explore the resulting effect on the He ii transverse proximity effect signal. Fluctuations in intergalactic medium density and the ultraviolet background, as well as the unknown orientation of the foreground quasar, result in a large variance of the He ii Lyα transmission along the background sightline. We develop a fully Bayesian statistical formalism to compare far-ultraviolet He ii Lyα transmission spectra of the background quasars to our models, and extract joint constraints on t
age and Ωobsc for the six Schmidt et al. foreground quasars with the highest implied He ii photoionization rates. Our analysis suggests a bimodal distribution of quasar emission properties, whereby one foreground quasar, associated with a strong He ii transmission spike, is relatively old (22 Myr) and unobscured (

Ω

obsc

<
35
%

), whereas three others are either younger than 10 Myr or highly obscured (

Ω

obsc

>
70
%

).
VERITAS Observations of the BL Lac Object TXS 0506+056
Authors: Abeysekara A. U. , Archer A. , Benbow W. , Bird R. , Brill A. , Brose R. , Buckley J. H. , Christiansen J. L. , Chromey A. J. , Daniel M. K. , Falcone A. , Feng Q. , Finley J. P. , Fortson L. , Furniss A. , Gillanders G. H. , Gueta O. , Hanna D. , Hervet O. , Holder J. , Hughes G. , Humensky T. B. , Johnson C. A. , Kaaret P. , Kar P. , Kelley-Hoskins N. , Kertzman M. , Kieda D. , Krause M. , Krennrich F. , Lang M. J. , Moriarty P. , Mukherjee R. , O’Brien S. , Ong R. A. , Otte A. N. , Park N. , Petrashyk A. , Pohl M. , Pueschel E. , Quinn J. , Ragan K. , Reynolds P. T. , Richards G. T. , Roache E. , Rulten C. , Sadeh I. , Santander M. , Scott S. S. , Sembroski G. H. , Shahinyan K. , Tyler J. , Wakely S. P. , Weinstein A. , Wells R. M. , Wilcox P. , Wilhelm A. , Williams D. A. , Williamson T. J , Zitzer B. ,   (The VERITAS Collaboration), Kaur A. 
Published: July 2018

Abstract
On 2017 September 22, the IceCube Neutrino Observatory reported the detection of the high-energy neutrino event IC 170922A, of potential astrophysical origin. It was soon determined that the neutrino direction was consistent with the location of the gamma-ray blazar TXS 0506+056 (3FGL J0509.4+0541), which was in an elevated gamma-ray emission state as measured by the Fermi satellite. Very Energetic Radiation Imaging Telescope Array System (VERITAS) observations of the neutrino/blazar region started on 2017 September 23 in response to the neutrino alert and continued through 2018 February 6. While no significant very-high-energy (VHE; E > 100 GeV) emission was observed from the blazar by VERITAS in the two-week period immediately following the IceCube alert, TXS 0506+056 was detected by VERITAS with a significance of 5.8 standard deviations (σ) in the full 35 hr data set. The average photon flux of the source during this period was (8.9 ± 1.6) × 10−12 cm−2 s−1, or 1.6% of the Crab Nebula flux, above an energy threshold of 110 GeV, with a soft spectral index of 4.8 ± 1.3.
Mourir chez soi. Le cas de la médicalisation du domicile en Italie
Authors: Gusman Alessandro 
Published: July 2018

Selon les statistiques, la majorité des Italiens expriment le désir de mourir « chez eux ». Pourtant, moins de la moitié des décès surviennent à la maison, avec des différences régionales importantes. Sur la base des données d’un terrain de deux ans sur les soins palliatifs au Piémont, cet article explore la dimension morale de la « maison » comme espace des relations intimes et des obligations familiales, essentielle en vue d’une approche idéale d’une « bonne vie », mais aussi d’une « bonne mort ». Il aborde également les transformations de l’espace domestique lorsqu’il devient un lieu de soins, traite des tensions familiales au regard des décisions relatives à la fin de vie, et enfin de la restructuration des réseaux familiaux dans ces situations.
Fixer le prix des entreprises
Authors: Benquet Marlène 
Published: July 2018

Résumé Comment décider du juste prix d'une entreprise ? La réponse à cette question est la principale activité des fonds de capital investissement, acteurs centraux de la nouvelle phase de financiarisation de l'économie. Ce texte aborde l'analyse des manières de fixer les prix comme un moment, particulièrement crucial, de la circulation de l'argent dans l'espace social et de sa distribution entre secteurs et groupes d'individus particuliers. La détermination des prix est pensée comme une opération d'évaluation autant que de répartition des capitaux appropriables. Il consiste à montrer, à partir de données qualitatives, comment les modalités concrètes et locales de fixation des prix participent à la solidification d'un régime massif d'accumulation de capital. Pour ce faire, il distingue trois conditionnements de la formation des prix : par les règles d'accès au capital des membres des fonds d'investissement, « la raison du prix » ; par les anticipations de capital transférable de l'entreprise vers les fonds, « le niveau théorique du prix » ; par les mécanismes de coordination entre les différents participants à l'échange, « l'effectivité du prix ».
Transepithelial Photorefractive Keratectomy in Moderate to High Astigmatism With a Non-wavefront–Guided Aberration-Neutral Ablation Profile
Authors: de Ortueta Diego , von Rüden Dennis , Verma Shwetabh , Magnago Thomas , Arba-Mosquera Samuel 
Published: July 2018

PURPOSE:
To evaluate the outcomes of transepithelial photorefractive keratectomy (PRK) in moderate to high astigmatism with a non-wavefront–guided aberration-neutral ablation profile using SmartPulse allocation.

METHODS:
In this retrospective study, myopic patients with a preoperative cylinder of 2.00 diopters (D) or greater were analyzed at 3 months of follow-up. Transepithelial PRK treatments were performed in each patient with the Amaris 1050RS laser (SCHWIND eye-tech-solutions, Kleinostheim, Germany) creating aspheric ablation profiles by applying a SmartPulse allocation. Standard examinations and wavefront analyses were included for low and high ocular residual astigmatism subgroups.

RESULTS:

Fifty-eight eyes (44 patients) were included in the cohort. The eyes were divided into separate ocular residual astigmatism subgroups: 17 eyes presented with less than 0.50 D (low ocular residual astigmatism) and 24 eyes with greater than 0.75 D (high ocular residual astigmatism). The mean refractive cylinder in the entire cohort was 2.84 ± 0.86 D preoperatively and 0.40 ± 0.39 D postoperatively, with 81% of the eyes within 0.75 D of the target astigmatism. At 3 months of follow-up, significant improvement (
P
< .05) was seen in terms of sphere, cylinder, spherical equivalent, and uncorrected (UDVA) and corrected (CDVA) distance visual acuity. CDVA improved in 40% of eyes and 3% of eyes lost one line of CDVA. No clinically relevant changes were seen in higher order aberrations. The refractive changes showed an excellent match with the keratometric changes. The difference between the low and high ocular residual astigmatism subgroups was not significant except for the change of Snellen lines of CDVA (
P
< .05).

CONCLUSIONS:

Transepithelial PRK using a non-wavefront–guided aberration-neutral ablation profile performed by applying SmartPulse allocation yielded excellent visual outcomes. The preoperative astigmatism was reduced to subclinical values. Both subgroups were effective in terms of UDVA, CDVA, spherical and astigmatic correction, and preserving higher order aberrations. However, the low ocular residual astigmatism subgroup was slightly more prone to gain lines of CDVA.

[
J Refract Surg.
2018;34(7):466–474.]