bluuebunny/crossref_metadata_2025_split huggingface dataset:
Funcionamiento y repercusión familiar en adolescentes embarazadas atendidas en el instituto nacional materno perinatal periodo Enero – Marzo 2013.
Authors: Alegría Nelly Ojeda 
Published: January 2019

Objetivo. Caracterizar. Desde un enfoque familiar, a las adolescentes embarazadas que se atienden en Instituto Nacional Materno Perinatal. Materiales y métodos. El universo estudiado comprendió a todas las adolescentes hospitalizadas en el servicio de gineco obstetricia de Adolescencia, durante el periodo de enero a marzo año 2011. Se analizó los informes Sociales, Psicológicos y Médicos de las historias clínica. Fueron estudiadas las variables edad, grado de instrucción, procedencia, estado civil, ocupación, edad de la pareja, ocupación de la pareja, relación de pareja, N° de parejas sexuales, N° de hijos, ocupación del padre, ocupación de la madre, clasificación de la familia, funcionamiento familiar, N de hermanos, factores protectores, vínculo afectivo, atención clínica, problemas de salud, problemas sociales, proyecto de vida y repercusión familiar del embarazo en la adolescencia como problema de salud.
Orbital Clustering in the Distant Solar System
Authors: Brown Michael E. , Batygin Konstantin 
Published: January 2019

Abstract
The most distant Kuiper Belt objects (KBOs) appear to be clustered in longitude of perihelion and in orbital pole position. To date, the only two suggestions for the cause of these apparent clusterings have been either the effects of observational bias or the existence of a distant giant planet in an eccentric inclined orbit known as Planet Nine. To determine if observational bias can be the cause of these apparent clusterings, we develop a rigorous method of quantifying the observational biases in the observations of longitude of perihelion and orbital pole position. From this now more complete understanding of the biases, we calculate that the probability that these distant KBOs would be clustered as strongly as observed in both longitude of perihelion and in orbital pole position is only 0.2%. While explanations other than Planet Nine may someday be found, the statistical significance of this clustering is now difficult to discount.
Shepherding in a Self-gravitating Disk of Trans-Neptunian Objects
Authors: Sefilian Antranik A. , Touma Jihad R. 
Published: January 2019

Abstract
A relatively massive and moderately eccentric disk of trans-Neptunian objects (TNOs) can effectively counteract apse precession induced by the outer planets, and in the process shepherd highly eccentric members of its population into nearly stationary configurations that are antialigned with the disk itself. We were sufficiently intrigued by this remarkable feature to embark on an extensive exploration of the full spatial dynamics sustained by the combined action of giant planets and a massive trans-Neptunian debris disk. In the process, we identified ranges of disk mass, eccentricity, and precession rate that allow apse-clustered populations that faithfully reproduce key orbital properties of the much-discussed TNO population. The shepherding disk hypothesis is, to be sure, complementary to any potential ninth member of the solar system pantheon, and could obviate the need for it altogether. We discuss its essential ingredients in the context of solar system formation and evolution, and argue for their naturalness in view of the growing body of observational and theoretical knowledge about self-gravitating disks around massive bodies, extra-solar debris disks included.
The Orbital Eccentricity of Small Planet Systems
Authors: Eylen Vincent Van , Albrecht Simon , Huang Xu , MacDonald Mariah G. , Dawson Rebekah I. , Cai Maxwell X. , Foreman-Mackey Daniel , Lundkvist Mia S. , Aguirre Victor Silva , Snellen Ignas , Winn Joshua N. 
Published: January 2019

Abstract
We determine the orbital eccentricities of individual small Kepler planets, through a combination of asteroseismology and transit light-curve analysis. We are able to constrain the eccentricities of 51 systems with a single transiting planet, which supplement our previous measurements of 66 planets in multi-planet systems. Through a Bayesian hierarchical analysis, we find evidence that systems with only one detected transiting planet have a different eccentricity distribution than systems with multiple detected transiting planets. The eccentricity distribution of the single-transiting systems is well described by the positive half of a zero-mean Gaussian distribution with a dispersion σ

e
= 0.32 ± 0.06, while the multiple-transit systems are consistent with

. A mixture model suggests a fraction of

of single-transiting systems have a moderate eccentricity, represented by a Rayleigh distribution that peaks at

. This finding may reflect differences in the formation pathways of systems with different numbers of transiting planets. We investigate the possibility that eccentricities are self-excited in closely packed planetary systems, as well as the influence of long-period giant companion planets. We find that both mechanisms can qualitatively explain the observations. We do not find any evidence for a correlation between eccentricity and stellar metallicity, as has been seen for giant planets. Neither do we find any evidence that orbital eccentricity is linked to the detection of a companion star. Along with this paper, we make available all of the parameters and uncertainties in the eccentricity distributions, as well as the properties of individual systems, for use in future studies.
PLCK G165.7+67.0: Analysis of a Massive Lensing Cluster in a Hubble Space Telescope Census of Submillimeter Giant Arcs Selected Using Planck/Herschel
Authors: Frye Brenda L. , Pascale Massimo , Qin Yujing , Zitrin Adi , Diego José , Walth Greg , Yan Haojing , Conselice Christopher J. , Alpaslan Mehmet , Bauer Adam , Busoni Lorenzo , Coe Dan , Cohen Seth H. , Dole Hervé , Donahue Megan , Georgiev Iskren , Jansen Rolf A. , Limousin Marceau , Livermore Rachael , Norman Dara , Rabien Sebastian , Windhorst Rogier A. 
Published: January 2019

Abstract
We present Hubble Space Telescope WFC3-IR imaging in the fields of six apparently bright dusty star-forming galaxies (DSFGs) at z = 2–4 identified by their rest-frame far-infrared colors using the Planck and Herschel space facilities. We detect near-infrared counterparts for all six submillimeter sources, allowing us to undertake strong-lensing analyses. One field in particular stands out for its prominent giant arcs, PLCK G165.7+67.0 (G165). After combining the color and morphological information, we identify 11 sets of image multiplicities in this one field. We construct a strong-lensing model constrained by this lensing evidence, which uncovers a bimodal spatial mass distribution, and from which we measure a mass of (2.6 ± 0.11) × 1014
M
⊙ within ∼250 kpc. The bright (S
350 ≈ 750 mJy) DSFG appears as two images: a giant arc with a spatial extent of

that is merging with the critical curve, and a lower-magnification counterimage that is detected in our new longer-wavelength ground- and space-based imaging data. Using our ground-based spectroscopy, we calculate a dynamical mass of

M
⊙ to the same fixed radius, although this value may be inflated relative to the true value if the velocity distribution is enhanced in the line-of-sight direction. We suggest that the bimodal mass taken in combination with the weak X-ray flux and low SZ decrement may be explained as a pre-merger for which the intracluster gas is diluted along the line of sight, while the integrated surface mass density is supercritical to strong-lensing effects.
High-resolution ALMA Observations of HD 100546: Asymmetric Circumstellar Ring and Circumplanetary Disk Upper Limits
Authors: Pineda Jaime E. , Szulágyi Judit , Quanz Sascha P. , van Dishoeck Ewine F. , Garufi Antonio , Meru Farzana , Mulders Gijs D. , Testi Leonardo , Meyer Michael R. , Reggiani Maddalena 
Published: January 2019

Abstract
We present long-baseline Atacama Large Millimeter/submillimeter Array observations of the 870 μm dust continuum emission and CO (3–2) from the protoplanetary disk around the Herbig Ae/Be star HD 100546, which is one of the few systems claimed to have two young embedded planets. These observations achieve a resolution of 4 au (3.8 mas), an rms noise of 66 μJy beam−1, and reveal an asymmetric ring between ∼20 and 40 au with largely optically thin dust continuum emission. This ring is well fit by two concentric and overlapping Gaussian rings of different widths and a Vortex. In addition, an unresolved component is detected at a position consistent with the central star, which may trace the central inner disk (<2 au in radius). We report a lack of compact continuum emission at the positions of both claimed protoplanets. We use this result to constrain the circumplanetary disk (CPD) mass and size of 1.44 M
⊕ and 0.44 au in the optically thin and thick regimes, respectively, for the case of the previously directly imaged protoplanet candidate at ∼55 au (HD 100546 b). We compare these empirical CPD constraints to previous numerical simulations. This suggests that HD 100546 b is inconsistent with several planet accretion models, while gas-starved models are also still compatible. We estimate the planetary mass as 1.65 M

J
using the relation between planet, circumstellar, and circumplanetary masses derived from numerical simulations. Finally, the CO-integrated intensity map shows a possible spiral arm feature that could match the spiral features identified in near-infrared scattered light polarized emission, which suggests a real spiral feature in the disk surface that needs to be confirmed with further observations.
General Relativistic Surface Degrees of Freedom in Perturbed Hybrid Stars
Authors: Pereira Jonas P. , Lugones Germán 
Published: January 2019

Abstract
We study how the nature of a hybrid star (perfect fluid, solid, or a mixture of them) could be related to the induction of general relativistic surface degrees of freedom on phase-splitting surfaces upon perturbation of its phases. We work in the scope of phase conversions in the vicinities of sharp phase transition surfaces whose timescales are either much smaller (rapid conversions) or larger (slow conversions) than those of the perturbations (

ω

−
1

, where ω is a characteristic frequency of oscillation of the star). In this first approach, perturbations are assumed to be purely radial. We show that surface degrees of freedom could emerge when either the core or the crust of a hybrid star is solid and phase conversions close to a phase-splitting surface are rapid. We also show how this would change the usual stability rule for solid hybrid stars, namely

∂

M

0

/

∂

ρ

c

≥
0

, where M
0 is the total mass to the background hybrid star and

ρ

c

is its central density. Further consequences of our analysis for asteroseismology are also briefly discussed.
The Dynamics, Structure, and Fate of a Young Cluster during Gas Dispersal: Hectoschelle, Chandra, Spitzer, and Gaia Observations of Cep OB3b
Authors: Karnath N. , Prchlik J. J. , Gutermuth R. A. , Allen T. S. , Megeath S. T. , Pipher J. L. , Wolk S. , Jeffries R. D. 
Published: January 2019

Abstract
We present a study of the kinematics and structure of the Cep OB3b cluster based on new spectra obtained with the Hectoschelle spectrograph on the MMT and data from Spitzer, Chandra, and Gaia. At a distance of 819 ± 16 pc, Cep OB3b is one of the closest examples of a young (∼3–5 Myr), large (∼3000 total members) cluster at the late stages of gas dispersal. The cluster is broken into two subclusters surrounded by a lower density halo. We fit the empirical density law of King to each subcluster to constrain their sizes and structure. The richer eastern subcluster has circular symmetry, a modest central density, and lacks molecular gas toward its core, suggesting it has undergone expansion due to gas dispersal. In contrast, the western subcluster deviates from circular symmetry, has a smaller core size, and contains significant molecular gas near its core, suggesting that it is in an earlier phase of gas dispersal. We present posterior probability distributions for the velocity dispersions from the Hectoschelle spectra. The east will continue to expand and likely form a bound cluster with ∼35% of stars remaining. The west is undergoing slower gas dispersal and will potentially form a bound cluster with ∼75% of stars remaining. If the halo dissipates, this will leave two independent clusters with ∼300 members; proper motions suggest that the two subcluster are not bound to each other.
Deceleration of C iv and Si iv Broad Absorption Lines in X-Ray Bright Quasar SDSS-J092345+512710
Authors: Joshi Ravi , Srianand Raghunathan , Chand Hum , Wu Xue-Bing , Noterdaeme Pasquier , Petitjean Patrick , Ho Luis C. 
Published: January 2019

Abstract
We report a synchronized kinematic shift of C iv and Si iv broad absorption lines (BAL) in a high-ionization, radio-loud, and X-ray bright quasar SDSS-J092345+512710 (at

∼ 2.1627). This quasar shows two broad absorption components (blue component at v ∼ 14,000 km s−1, and red component at v ∼ 4000 km s−1 with respect to the quasars systemic redshift). The absorption profiles of C iv and Si iv BAL of the blue component show a decrease in outflow velocity with an average deceleration rate of

cm s−2 and

cm s−2 over a rest-frame time span of 4.15 yr. We do not see any acceleration-like signature in the red component. This is consistent with dramatic variabilities usually seen at high velocities. During our monitoring period the quasar has shown no strong continuum variability. We suggest the observed variability could be related to the time dependent changes in disk wind parameters like launching radius, initial flow velocity, or mass outflow rate.
Using APOGEE Wide Binaries to Test Chemical Tagging with Dwarf Stars
Authors: Andrews Jeff J. , Anguiano Borja , Chanamé Julio , Agüeros Marcel A. , Lewis Hannah M. , Hayes Christian R. , Majewski Steven R. 
Published: January 2019

Abstract
Stars of a common origin are thought to have similar, if not nearly identical, chemistry. Chemical tagging seeks to exploit this fact to identify Milky Way subpopulations through their unique chemical fingerprints. In this work, we compare the chemical abundances of dwarf stars in wide binaries to test the abundance consistency of stars of a common origin. Our sample of 31 wide binaries is identified from a catalog produced by cross-matching Apache Point Observatory Galactic Evolution Experiment spectroscopic survey (APOGEE) stars with UCAC5 astrometry, and we confirm the fidelity of this sample with precision parallaxes from Gaia DR2. For as many as 14 separate elements, we compare the abundances between components of our wide binaries, finding they have very similar chemistry (typically within 0.1 dex). This level of consistency is more similar than can be expected from stars with different origins (which show typical abundance differences of 0.3–0.4 dex within our sample). For the best-measured elements, Fe, Si, K, Ca, Mn, and Ni, these differences are reduced to 0.05–0.08 dex when selecting pairs of dwarf stars with similar temperatures. Our results suggest that APOGEE dwarf stars may currently be used for chemical tagging at the level of ∼0.1 dex or at the level of ∼0.05 dex when restricting for the best-measured elements in stars of similar temperatures. Larger wide binary catalogs may provide calibration sets, in complement to open cluster samples, for ongoing spectroscopic surveys.
Gamma-Ray Production in the Extended Halo of the Galaxy and Possible Implications for the Origin of Galactic Cosmic Rays
Authors: Liu Ruo-Yu , Yan Huirong , Wang Xiang-Yu , Shao Shi , Li Hui 
Published: January 2019

Abstract
Various studies have implied the existence of a gaseous halo around the Galaxy extending out to ∼100 kpc. Galactic cosmic rays (CRs) that propagate to the halo, either by diffusion or by convection with the possibly existing large-scale Galactic wind, can interact with the gas therein and produce gamma-rays via proton–proton collision. We calculate the CR distribution in the halo and the gamma-ray flux, and explore the dependence of the result on model parameters such as diffusion coefficient, CR luminosity, and CR spectral index. We find that the current measurement of isotropic gamma-ray background (IGRB) at ≲TeV with the Fermi Large Area Telescope already approaches a level that can provide interesting constraints on the properties of Galactic CR (e.g., with CR luminosity L
CR ≤ 1041 erg s−1). We also discuss the possibilities of the Fermi bubble and IceCube neutrinos originating from the proton–proton collision between CRs and gas in the halo, as well as the implication of our results for the baryon budget of the hot circumgalactic medium of our Galaxy. Given that the isotropic gamma-ray background is likely to be dominated by unresolved extragalactic sources, future telescopes may extract more individual sources from the IGRB, and hence put even more stringent restrictions on the relevant quantities (such as Galactic CR luminosity and baryon budget in the halo) in the presence of a turbulent halo that we consider.
Structure of a Protobinary System: An Asymmetric Circumbinary Disk and Spiral Arms
Authors: Matsumoto Tomoaki , Saigo Kazuya , Takakuwa Shigehisa 
Published: January 2019

Abstract
We investigate the gas structures around young binary stars using three-dimensional numerical simulations. Each model exhibits circumstellar disks, spiral arms, and a circumbinary disk with an inner gap or cavity. The circumbinary disk has an asymmetric pattern rotating at an angular velocity of approximately one-fourth of the binary orbit of the moderate-temperature models. Because of this asymmetry, the circumbinary disk has a density bump and a vortex, both of which continue to exist until the end of our calculation. The density bump and vortex are attributed to enhanced angular momentum, which is promoted by the gravitational torque of the stars. In a hot model (c ≥ 2.0), the asymmetry rotates considerably more slowly than in the moderate-temperature models. The cold models (c ≤ 0.02) exhibit eccentric circumbinary disks, the precession of which is approximated by a secular motion of the ballistic particles. The asymmetry in the circumbinary disk does not depend on the mass ratio, but it becomes less clear as the specific angular momentum of the infalling envelope increases. The relative accretion rate onto the stars is sensitive to the angular momentum of the infalling envelope. For envelopes with constant angular momentum, the secondary tends to have a higher accretion rate than the primary, except in very low angular momentum cases. For envelopes with a constant angular velocity, the primary has a higher accretion rate than the secondary because gas with low specific angular momentum falls along the polar directions.
Revealing the Milky Way’s Hidden Circumgalactic Medium with the Cosmic Origins Spectrograph Quasar Database for Galactic Absorption Lines
Authors: Zheng Y. , Peek J. E. G. , Putman M. E. , Werk J. K. 
Published: January 2019

Abstract
Every quasar (quasi-stellar object; QSO) spectrum contains absorption-line signatures from the interstellar medium, disk-halo interface, and circumgalactic medium (CGM) of the Milky Way (MW). We analyze Hubble Space Telescope/Cosmic Origins Spectrograph (COS) spectra of 132 QSOs to study the significance and origin of Si iv absorption at

km s−1 in the Galactic halo. The gas in the north predominantly falls in at

km s−1, whereas in the south, no such pattern is observed. The Si iv column density has an average and a standard deviation of

cm−2. At

,

does not significantly correlate with b, which cannot be explained by a commonly adopted flat-slab geometry. We propose a two-component model to reconstruct the

–b distribution: a plane-parallel component

to account for the MW’s disk-halo interface and a global component

to reproduce the weak dependence on b. We find

cm−2 and

cm−2 on the basis of Bayesian analyses and block bootstrapping. The global component is most likely to have a Galactic origin, although its exact location is uncertain. If it were associated with the MW’s CGM, we would find

for the cool gas at all velocities in the Galactic halo. Our analyses show that there is likely a considerable amount of gas at

km s−1 hidden in the MW’s CGM. Along with this work, we make our QSO data set publicly available as the COS Quasar Database for Galactic Absorption Lines (COS-GAL).
Frequency-dependent Template Profiles for High-precision Pulsar Timing
Authors: Pennucci Timothy T. 
Published: January 2019

Abstract
Pulsar timing experiments require high-fidelity template profiles in order to minimize the biases in pulse time-of-arrival (TOA) measurements and their uncertainties. Efforts to acquire more precise TOAs given the fixed effective area of telescopes, finite receiver noise, and limited integration time have led pulsar astronomers to the solution of implementing ultra-wideband receivers. This solution, however, has run up against the problem that pulse profile shapes evolve with frequency, which raises the question of how to properly measure and analyze TOAs obtained using template-matching methods. This paper proposes a new method for one facet of this problem, that of template profile generation, and demonstrates it on the well-timed millisecond pulsar J1713+0747. Specifically, we decompose pulse profile evolution into a linear combination of basis eigenvectors, the coefficients of which change slowly with frequency such that their evolution is modeled simply by a sum of low-degree piecewise polynomial spline functions. These noise-free, high-fidelity, frequency-dependent templates can be used to make measurements of so-called “wideband TOAs” simultaneously with an estimate of the instantaneous dispersion measure. The use of wideband TOAs is becoming important for pulsar timing array experiments, as the volume of data sets comprised of conventional, subbanded TOAs are quickly becoming unwieldy for the Bayesian analyses needed to uncover latent gravitational wave signals. Although motivated by high-precision timing experiments, our technique is applicable in more general pulsar observations.
Star Clusters in the Elliptical Galaxy NGC 4589 Hosting a Calcium-rich SN Ib (SN 2005cz)
Authors: Lee Myung Gyoon , Jang In Sung , Kang Jisu 
Published: January 2019

Abstract
NGC 4589, a bright E2 merger-remnant galaxy, hosts the peculiar fast and faint calcium-rich SN Ib SN 2005cz. The progenitor of Ca-rich SNe Ib has been controversial: it could be (1) a young, massive star with 6–12 M
⊙ in a binary system, or (2) an old, low-mass star in a binary system that was kicked out from the galaxy center. Moreover, previous distance estimates for this galaxy have shown a large spread, ranging from 20 to 60 Mpc. Thus, using archival Hubble
Space
Telescope/ACS F435W, F555W, and F814W images, we search for star clusters in NGC 4589 in order to help resolve these issues. We find a small population of young star clusters with 25 < V ≤ 27 (−7.1 < M

V
≤ −5.1) mag and age <1 Gyr in the central region at R < 0.′5 (<3.8 kpc), thus supporting the massive-star progenitor scenario for SN 2005cz. In addition to young star clusters, we also find a large population of old globular clusters. In contrast to previous results in the literature, we find that the color distribution of the globular clusters is clearly bimodal. The turnover (Vega) magnitude in the V-band luminosity functions of the blue (metal-poor) globular clusters is determined to be V
0(max) = 24.40 ± 0.10 mag. We derive the total number of globular clusters, N
GC = 640 ± 50, and the specific frequency, S

N
= 1.7 ± 0.2. Adopting a calibration for the metal-poor globular clusters, M

V
(max) = −7.66 ± 0.14 mag, we derive a distance to this galaxy: (m − M)0 = 32.06 ± 0.10(ran) ± 0.15(sys) (d = 25.8 ± 2.2 Mpc).