bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Single-pulse Study of PSR J1022+1001 Using the FAST Radio Telescope
Authors: Feng Yi , Hobbs G. , Li D. , Dai S. , Zhu W. W. , Yue Y. L. , Wang P. , Zhang S.-B. , Qian L. , Zhang L. , Wang S. Q. , Miao C. C. , Yuan M. , Zhang Y.-K. 
Published: February 2021

Abstract
Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), we have recorded ∼105 single pulses from PSR J1022+1001. We studied the polarization properties, their energy distribution, and their times of arrival. This is only possible with the high sensitivity available using FAST. There is no indication that PSR J1022+1001 exhibits giant pulse, nulling, or traditional mode changing phenomena. The energy in the leading and trailing components of the integrated profile is shown to be correlated. The degree of both linear and circular polarization increases with the pulse flux density for individual pulses. Our data indicates that pulse jitter leads to an excess noise in the timing residuals of 67 ns when scaled to one hour, which is consistent with Liu et al. We have unsuccessfully trialed various methods to improve timing precision through the selection of specific single pulses. Our work demonstrates that FAST can detect individual pulses from pulsars that are observed in order to detect and study gravitational waves. This capability enables detailed studies, and parameterization, of the noise processes that affect the sensitivity of a pulsar timing array.
Constraining the Quasar Radio-loud Fraction at z ∼ 6 with Deep Radio Observations
Authors: Liu Yuanqi , Wang Ran , Momjian Emmanuel , Bañados Eduardo , Zeimann Greg , Willott Chris J. , Matsuoka Yoshiki , Omont Alain , Shao Yali , Li Qiong , Li Jianan 
Published: February 2021

Abstract
We carry out a series of deep Karl G. Jansky Very Large Array (VLA) S-band observations of a sample of 21 quasars at z ∼ 6. The new observations expand the searches of radio continuum emission to the optically faint quasar population at the highest redshift with rest-frame

4400

Å

luminosities down to

3
×

10

11

L

⊙

. We report the detections of two new radio-loud quasars: CFHQS J2242+0334 (hereafter J2242+0334) at z = 5.88 and CFHQS J0227−0605 (hereafter J0227−0605) at z = 6.20, detected with 3 GHz flux densities of

87.0
±
6.3

μ
Jy

and

55.4
±
6.7

μ
Jy

, respectively. Their radio loudnesses are estimated to be 54.9 ± 4.7 and 16.5 ± 3.2, respectively. To better constrain the radio-loud fraction (RLF), we combine the new measurements with the archival VLA L-band data as well as available data from the literature, considering the upper limits for non-detections and possible selection effects. The final derived RLF is 9.4 ± 5.7% for the optically selected quasars at z ∼ 6. We also compare the RLF to that of the quasar samples at low redshift and check the RLF in different quasar luminosity bins. The RLF for the optically faint objects is still poorly constrained due to the limited sample size. Our results show no evidence of significant quasar RLF evolution with redshift. There is also no clear trend of RLF evolution with quasar UV/optical luminosity due to the limited sample size of optically faint objects with deep radio observations.
The SAMI Galaxy Survey: Kinematics of Stars and Gas in Brightest Group Galaxies—The Role of Group Dynamics
Authors: Raouf Mojtaba , Smith Rory , Khosroshahi Habib G. , Sande Jesse van de , Bryant Julia J. , Cortese Luca , Brough S. , Croom Scott M. , Hwang Ho Seong , Driver Simon , López-Sánchez Ángel R. , Ko Jongwan , Kim Jae-Woo , Shin Jihye , Scott Nicholas , Bland-Hawthorn Joss , Richards Samuel N. , Owers Matt , Lawrence J. S. , Konstantopoulos Iraklis S. 
Published: February 2021

Abstract
We study the stellar and gas kinematics of the brightest group galaxies (BGGs) in dynamically relaxed and unrelaxed galaxy groups for a sample of 154 galaxies in the SAMI galaxy survey. We characterize the dynamical state of the groups using the luminosity gap between the two most luminous galaxies and the BGG offset from the luminosity centroid of the group. We find that the misalignment between the rotation axis of gas and stellar components is more frequent in the BGGs in unrelaxed groups, although with quite low statistical significance. Meanwhile, galaxies whose stellar dynamics would be classified as “regular rotators” based on their kinemetry are more common in relaxed groups. We confirm that this dependency on group dynamical state remains valid at fixed stellar mass and Sérsic index. The observed trend could potentially originate from a differing BGG accretion history in virialized and evolving groups. Among the halo relaxation probes, the group BGG offset appears to play a stronger role than the luminosity gap on the stellar kinematic differences of the BGGs. However, both the group BGG offset and luminosity gap appear to roughly equally drive the misalignment between the gas and stellar component of the BGGs in one direction. This study offers the first evidence that the dynamical state of galaxy groups may influence the BGG's stellar and gas kinematics, and we call for further studies using a larger sample with higher signal-to-noise.
Clouds in Three-dimensional Models of Hot Jupiters over a Wide Range of Temperatures. I. Thermal Structures and Broadband Phase-curve Predictions
Authors: Roman Michael T. , Kempton Eliza M.-R. , Rauscher Emily , Harada Caleb K. , Bean Jacob L. , Stevenson Kevin B. 
Published: February 2021

Abstract
Using a general circulation model (GCM), we investigate trends in simulated hot Jupiter atmospheres for a range of irradiation temperatures (1500–4000 K), surface gravities (10 and 40 m s−2), and cloud conditions. Our models include simplified temperature-dependent clouds with radiative feedback and show how different cloud compositions, vertical thicknesses, and opacities shape hot Jupiter atmospheres by potentially increasing planetary albedos, decreasing photospheric pressures and nightside temperatures, and in some cases producing strong dayside thermal inversions. With decreasing irradiation, clouds progressively form on the nightside and cooler western limb, followed by the eastern limb and central dayside. We find that clouds significantly modify the radiative transport and affect the observable properties of planets colder than T
irr ≈ 3000 K (T
eq ≈ 2100 K) depending on the clouds’ vertical extent. The precise strength of expected effects depends on the assumed parameters, but trends in predicted phase curves emerge from an ensemble of simulations. Clouds lead to larger phase-curve amplitudes and smaller phase-curve offsets at IR wavelengths, compared to cloud-free models. At optical wavelengths, we predict mostly westward phase-curve offsets at intermediate temperatures (T
irr ≈ 2000–3500 K) with clouds confined to the nightside and western limb. If clouds are vertically compact (i.e., on the order of a pressure scale height in thickness), their distributions and effects become more complicated as different condensates form at different heights—some too deep to significantly affect the observable atmosphere. Our results have implications for interpreting the diversity of phase-curve observations of planets with T
irr ≲ 3000 K.
Extremely Energetic Supernova Explosions Embedded in a Massive Circumstellar Medium: The Case of SN 2016aps
Authors: Suzuki Akihiro , Nicholl Matt , Moriya Takashi J. , Takiwaki Tomoya 
Published: February 2021

Abstract
We perform one-dimensional radiation-hydrodynamic simulations of energetic supernova (SN) ejecta colliding with a massive circumstellar medium (CSM) aimed at explaining SN 2016aps, likely the brightest SN observed to date. SN 2016aps was a superluminous Type IIn SN, which released as much as

erg of thermal radiation. Our results suggest that the multiband light curve of SN 2016aps is well explained by the collision of a

SN ejecta with the explosion energy of 1052 erg and a

wind-like CSM with the outer radius of 1016 cm, that is, a hypernova explosion embedded in a massive CSM. This finding indicates that very massive stars with initial masses larger than

, which supposedly produce highly energetic SNe, occasionally eject their hydrogen-rich envelopes shortly before the core collapse. We suggest that the pulsational pair-instability SNe may provide a natural explanation for the massive CSM and the energetic explosion. We also provide the relations among the peak luminosity, the radiated energy and the rise time for interacting SNe with the kinetic energy of 1052 erg, which can be used for interpreting SN 2016aps–like objects in future surveys.
Identifying Strong Gravitational-wave Lensing during the Second Observing Run of Advanced LIGO and Advanced Virgo
Authors: Liu Xiaoshu , Hernandez Ignacio Magaña , Creighton Jolien 
Published: February 2021

Abstract
We perform Bayesian model selection with parameter estimation to identify potentially lensed gravitational-wave images from the second observing run (O2) of Advanced LIGO and Advanced Virgo. Specifically, we compute the Bayesian evidence for a pair of events being lensed or not lensed (unlensed) using nested sampling. We consider in the model selection the discrete coalescence phase shifts that can be induced if the gravitational-wave signal intersects with the lens caustics. We find that the pair of events, GW170104 and GW170814 with a π/2 coalescence phase shift, has a significant Bayes factor (

) favoring the lensing hypothesis. However, after taking into account the long time delay of approximately 7 months between events, the timing Bayes factor is significantly small (B

t
∼ 8.7 × 10−2). The prior probability for detecting strongly lensed pairs at O2 sensitivity is exceedingly small for both galaxy and galaxy cluster lensing. Combining the lensing and timing Bayes factors with the prior odds on lensing gives an odds ratio of

. With the value of the odds ratio after including model dependence of the timing and prior odds factors, we do not have strong evidence to demonstrate that the aforementioned pair is strongly lensed.
Where Have All the Solar-like Stars Gone? Rotation Period Detectability at Various Inclinations and Metallicities
Authors: Reinhold Timo , Shapiro Alexander I. , Witzke Veronika , Nèmec Nina-E. , Işık Emre , Solanki Sami K. 
Published: February 2021

Abstract
The plethora of photometric data collected by the Kepler space telescope has promoted the detection of tens of thousands of stellar rotation periods. However, these periods are not found to an equal extent among different spectral types. Interestingly, early G-type stars with near-solar rotation periods are strongly underrepresented among those stars with known rotation periods. In this study we investigate whether the small number of such stars can be explained by difficulties in the period determination from photometric time series. For that purpose, we generate model light curves of early G-type stars with solar rotation periods for different inclination angles, metallicities, and (magnitude-dependent) noise levels. We find that the detectability is determined by the predominant type of activity (i.e., spot or faculae domination) on the surface, which defines the degree of irregularity of the light curve, and further depends on the level of photometric noise. These two effects significantly complicate the period detection and explain the lack of solar-like stars with known near-solar rotation periods. We conclude that the rotation periods of the majority of solar-like stars with near-solar rotation periods remain undetected to date. Finally, we promote the use of new techniques to recover more periods of near-solar rotators.
RELICS-DP7: Spectroscopic Confirmation of a Dichromatic Primeval Galaxy at z ∼ 7
Authors: Pelliccia Debora , Strait Victoria , Lemaux Brian C. , Bradač Maruša , Coe Dan , Bolan Patricia , Bradley Larry D. , Frye Brenda , Gandhi Pratik J. , Mainali Ramesh , Mason Charlotte , Ouchi Masami , Sharon Keren , Trenti Michele , Zitrin Adi 
Published: February 2021

Abstract
We report the discovery of a spectroscopically confirmed strong Lyα emitter at z = 7.0281 ± 0.0003, observed as part of the Reionization Lensing Cluster Survey (RELICS). This galaxy, dubbed “Dichromatic Primeval Galaxy” at z ∼ 7 (DP7), shows two distinct components. While fairly unremarkable in terms of its ultraviolet (UV) luminosity (

∼
0.3

L

UV

*

, where

L

UV

*

is the characteristic luminosity), DP7 has one of the highest observed Lyα equivalent widths (EWs) among Lyα emitters at z > 6 (>200 Å in the rest frame). The strong Lyα emission generally suggests a young metal-poor, low-dust galaxy; however, we find that the UV slope β of the galaxy as a whole is redder than typical star-forming galaxies at these redshifts, −1.13 ± 0.84, likely indicating, on average, a considerable amount of dust obscuration, or an older stellar population. When we measure β for the two components separately, however, we find evidence of differing UV colors, suggesting two separate stellar populations. Also, we find that Lyα is spatially extended and likely larger than the galaxy size, hinting to the possible existence of a Lyα halo. Rejuvenation or merging events could explain these results. Either scenario requires an extreme stellar population, possibly including a component of Population III stars, or an obscured active galactic nucleus. DP7, with its low UV luminosity and high Lyα EW, represents the typical galaxies that are thought to be the major contribution to the reionization of the universe, and for this reason DP7 is an excellent target for follow-up with the James Webb Space Telescope.
Intermediate-mass Black Holes from High Massive-star Binary Fractions in Young Star Clusters
Authors: González Elena , Kremer Kyle , Chatterjee Sourav , Fragione Giacomo , Rodriguez Carl L. , Weatherford Newlin C. , Ye Claire S. , Rasio Frederic A. 
Published: February 2021

Abstract
Black holes formed in dense star clusters, where dynamical interactions are frequent, may have fundamentally different properties than those formed through isolated stellar evolution. Theoretical models for single-star evolution predict a gap in the black hole mass spectrum from roughly 40–120 M
⊙ caused by (pulsational) pair-instability supernovae. Motivated by the recent LIGO/Virgo event GW190521, we investigate whether black holes with masses within or in excess of this “upper-mass gap” can be formed dynamically in young star clusters through strong interactions of massive stars in binaries. We perform a set of N-body simulations using the CMC cluster-dynamics code to study the effects of the high-mass binary fraction on the formation and collision histories of the most massive stars and their remnants. We find that typical young star clusters with low metallicities and high binary fractions in massive stars can form several black holes in the upper-mass gap and often form at least one intermediate-mass black hole. These results provide strong evidence that dynamical interactions in young star clusters naturally lead to the formation of more massive black hole remnants.
Evolution of Retrograde Orbiters in an Active Galactic Nucleus Disk
Authors: Secunda Amy , Hernandez Betsy , Goodman Jeremy , Leigh Nathan W. C. , McKernan Barry , Ford K. E. Saavik , Adorno Jose I. 
Published: February 2021

Abstract
Active galactic nucleus (AGN) disks have been proposed as promising locations for the mergers of stellar-mass black hole binaries (BBHs). Much recent work has been done on this merger channel, but the majority focuses on stellar-mass black holes (BHs) orbiting in the prograde direction. Little work has been done to examine the impact of retrograde orbiters (ROs) on the formation and mergers of BBHs in AGN disks. Quantifying the retrograde contribution is important, as roughly half of all orbiters should initially be on retrograde orbits when the disk forms. We perform an analytic calculation of the evolution of ROs in an AGN disk. Because this evolution could cause the orbits of ROs to cross those of prograde BBHs, we derive the collision rate between a given RO and a given BBH orbiting in the prograde direction. In the examples given here, ROs in the inner region of the disk experience a rapid decrease in the semimajor axis of their orbits while also becoming highly eccentric in less than a million years. This rapid orbital evolution could lead to extreme mass ratio inspirals detectable by the Laser Interferometer Space Antenna. The collision rates of our example ROs with prograde BBHs in the migration trap depend strongly on the volume of the inner radiation-pressure-dominated region, which depends on the mass of the supermassive black hole (SMBH). Rates are lowest for larger-mass SMBHs, which dominate the AGN merger channel, suggesting that merger rates for this channel may not be significantly altered by ROs.
Le travail à domicile
Authors: Crespin Graciela C. , Debret Richard , Letailleur Danielle , Allombert Myriam , Zerbib Valérie 
Published: February 2021

Peut-on travailler avec un enfant tsa comme on travaille avec un enfant au développement typique ? La réponse est non. Si nous nous contentons de les recevoir dans nos bureaux de consultation et nous n’envisagerons pas d’aller au domicile, un certain nombre d’éléments de la problématique des enfants tsa ne viendra pas au jour, et il sera très difficile de les aborder. Cet article aborde les bénéfices de l’intervention au domicile pour les enfants et pour les parents. Le cas de Kofi et celui des sœurs jumelles, enfants suivis à domicile par des intervenants de l’ udap , en sont un exemple.
Impact d’empowerment psychologique sur l’engagement organisationnel affectif des enseignants d’enseignement secondaire public Tunisien
Authors: Zouari Ghazi , Dinari Sami 
Published: February 2021

La situation de travail difficile des employés remet en cause leur engagement et leur sentiment de fidélité envers l’organisation (Autissier et Wacheux, 2007). Toutefois, leurs perceptions dans leur milieu de travail permettent de trouver du sens aux efforts fournis et de renouer les liens avec l’organisation (Morin, 2003). D’où l’intérêt d’étudier l’influence perçue de l’empowerment psychologique (avec ses quatre cognitions) sur l’engagement organisationnel affectif des enseignants d’enseignement secondaire public Tunisien. Les résultats des équations structurelles menés sur un échantillon de 223 enseignants ont montré que trois parmi les quatre variables de l’empowerment psychologique ; « Sens du travail », « Sentiment d’autodétermination » et « Sentiment d’impact » ont chacune une influence positive et significative sur l’engagement organisationnel affectif tantôt dans une région tantôt dans l’autre.
Capital de mobilité internationale et développement des compétences transversales : cas des étudiant(e)s de la région des Hauts-de-France (Nord de Paris)
Authors: Dokou Gérard Akrikpan Kokou , Vernier Éric , Dang Rey , Houanti L’Hocine 
Published: February 2021

Cette recherche répond à la question de l’impact de la mobilité internationale sur le développement des compétences transversales parmi des étudiants impliqués dans des missions d’études ou de stages à l’étranger. En nous appuyant sur les travaux relatifs au capital de mobilité internationale spécifique aux étudiant(e)s (en cohérence avec le développement des compétences transversales), nous avons mené une étude quantitative longitudinale (avant et après la mobilité) auprès de 393 étudiants(e)s du nord de la France. Nous mettons en évidence l’impact positif et significatif de la mobilité internationale sur les compétences transversales, autour de trois thèmes : l’autonomie, le leadership et l’aptitude face aux changements.
Numerical Simulation of Thermal Solvent Replacing Steam under Steam Assisted Gravity Drainage SAGD Process
Authors: Li Weiqiang , Mamora Daulat D. 
Published: February 2021

Abstract
Steam Assisted Gravity Drainage (SAGD) is one successful thermal recovery technique applied in the Athabasca oil sands in Canada to produce the very viscous bitumen. Water for SAGD is limited in supply and expensive to treat and to generate steam. Consequently, we conducted a study into injecting high-temperature solvent instead of steam to recover Athabasca oil.
In this study, hexane (C6) coinjection at condensing condition is simulated using CMG STARS to analyze the drainage mechanism inside the vapor-solvent chamber. The production performance is compared with an equivalent steam injection case based on the same Athabasca reservoir condition.
Simulation results show that C6 is vaporized and transported into the vapor-solvent chamber. At the condensing condition, high temperature C6 reduces the viscosity of the bitumen more efficiently than steam and can displace out all the original oil. The oil production rate with C6 injection is about 1.5 to 2 times that of steam injection with oil recovery factor of about 100% oil initially-in-place. Most of the injected C6 can be recycled from the reservoir and from the produced oil, thus significantly reduce the solvent cost. Results of our study indicate that high-temperature solvent injection appears feasible although further technical and economic evaluation of the process is required.
The Zinc Finger Protein Zbtb18 Represses Expression of Class I Phosphatidylinositol 3-Kinase Subunits and Inhibits Plasma Cell Differentiation
Authors: Xie Bin , Khoyratty Tariq E. , Abu-Shah Enas , F. Cespedes Pablo , MacLean Andrew J. , Pirgova Gabriela , Hu Zhiyuan , Ahmed Ahmed A. , Dustin Michael L. , Udalova Irina A. , Arnon Tal I. 
Published: February 2021

Abstract
The PI3K pathway plays a key role in B cell activation and is important for the differentiation of Ab producing plasma cells (PCs). Although much is known about the molecular mechanisms that modulate PI3K signaling in B cells, the transcriptional regulation of PI3K expression is poorly understood. In this study, we identify the zinc finger protein Zbtb18 as a transcriptional repressor that directly binds enhancer/promoter regions of genes encoding class I PI3K regulatory subunits, subsequently limiting their expression, dampening PI3K signaling and suppressing PC responses. Following activation, dividing B cells progressively downregulated Zbtb18, allowing gradual amplification of PI3K signals and enhanced development of PCs. Human Zbtb18 displayed similar expression patterns and function in human B cells, acting to inhibit development of PCs. Furthermore, a number of Zbtb18 mutants identified in cancer patients showed loss of suppressor activity, which was also accompanied by impaired regulation of PI3K genes. Taken together, our study identifies Zbtb18 as a repressor of PC differentiation and reveals its previously unappreciated function as a transcription modulator of the PI3K signaling pathway.