bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detecting Isolated Stellar-mass Black Holes with the Roman Telescope
Authors: Sajadian Sedighe , Sahu Kailash C. 
Published: February 2023

Abstract
Isolated stellar-mass black holes (ISMBHs) are potentially discernible through microlensing observations, because they are expected to be long-duration microlensing events. In this work, we study the detection and characterization of ISMBHs using Roman observations. We simulate a large ensemble of such events, as they will be seen by Roman, and estimate the errors in the physical parameters of the lens objects, including their masses, distances, and proper motions, by calculating Fisher and covariance matrices. Since the ∼2.3 yr time gap between Roman’s first three observing seasons and its latter three seasons may lower the efficiency of its realization of microlensing events and characterization of ISMBHs, we additionally consider a scenario where we add a small number of additional observations—1 hr of observations, every 10 days, when the Bulge is observable during the large time gap—which is equivalent to a total of an additional day of observations with the Roman telescope. These extra observations increase Roman’s efficiency in terms of characterizing ISMBHs by ∼1%–2%, and, more importantly, they improve the robustness of the results, by avoiding possible degenerate solutions. By considering uniform and power-law mass functions (

dN

/

dM
∝

M

−
α

, α = 2, 1, 0.5) for ISMBHs in the range of [2, 50]M
⊙, we conclude that the Roman telescope will determine the physical parameters of the lenses (the mass, distance, and relative lens–source angular velocity) within <5% uncertainty, with efficiencies of 21% and 16%–18%, respectively. By considering these mass functions, we expect that during its mission the Roman telescope will detect and characterize 3–4, 15–17, and 22–24 ISMBHs through astrometric microlensing, with the relative errors for all physical parameters being less than 1%, 5%, and 10%, respectively. Microlensing events due to ISMBHs with masses ≃10–25M
⊙ that are located close to the observer, with D
l ≲ 0.5D
s, while the source is inside the Galactic disk, can be characterized with the fewest errors.
DESI Observations of the Andromeda Galaxy: Revealing the Immigration History of Our Nearest Neighbor
Authors: Dey Arjun , Najita Joan R. , Koposov Sergey E. , Josephy-Zack J. , Maxemin Gabriel , Bell Eric F. , Poppett C. , Patel E. , Beraldo e Silva L. , Raichoor A. , Schlegel D. , Lang D. , Meisner A. , Myers Adam D. , Aguilar J. , Ahlen S. , Allende Prieto C. , Brooks D. , Cooper A. P. , Dawson K. S. , Macorra A. de la , Doel P. , Font-Ribera A. , García-Bellido Juan , Gontcho A Gontcho S. , Guy J. , Honscheid K. , Kehoe R. , Kisner T. , Kremin A. , Landriau M. , Le Guillou L. , Levi Michael E. , Li T. S. , Martini Paul , Miquel R. , Moustakas J. , Nie Jundan , Palanque-Delabrouille N. , Prada F. , Schlafly E. F. , Sharples Ray M. , Tarlé Gregory , Ting 丁 Yuan-Sen 源森 , Tyas L. , Valluri M. , Wechsler Risa H. , Zou H. 
Published: February 2023

Abstract
We present Dark Energy Spectroscopic Instrument (DESI) observations of the inner halo of M31, which reveal the kinematics of a recent merger—a galactic immigration event—in exquisite detail. Of the 11,416 sources studied in 3.75 hr of on-sky exposure time, 7438 are M31 sources with well-measured radial velocities. The observations reveal intricate coherent kinematic structure in the positions and velocities of individual stars: streams, wedges, and chevrons. While hints of coherent structures have been previously detected in M31, this is the first time they have been seen with such detail and clarity in a galaxy beyond the Milky Way. We find clear kinematic evidence for shell structures in the Giant Stellar Stream, the Northeast Shelf, and Western Shelf regions. The kinematics are remarkably similar to the predictions of dynamical models constructed to explain the spatial morphology of the inner halo. The results are consistent with the interpretation that much of the substructure in the inner halo of M31 is produced by a single galactic immigration event 1–2 Gyr ago. Significant numbers of metal-rich stars ([Fe/H] > − 0.5) are present in all of the detected substructures, suggesting that the immigrating galaxy had an extended star formation history. We also investigate the ability of the shells and Giant Stellar Stream to constrain the gravitational potential of M31, and estimate the mass within a projected radius of 125 kpc to be

log

10

M

NFW

(
<
125

kpc
)

/

M

⊙

=

11.80

−
0.10

+
0.12

. The results herald a new era in our ability to study stars on a galactic scale and the immigration histories of galaxies.
Convection and Clouds under Different Planetary Gravities Simulated by a Small-domain Cloud-resolving Model
Authors: Liu Jiachen , Yang Jun , Zhang Yixiao , Tan Zhihong 
Published: February 2023

Abstract
In this study, we employ a cloud-resolving model to investigate how gravity influences convection and clouds in a small-domain (96 × 96 km) radiative–convective equilibrium. Our experiments are performed with a horizontal grid spacing of 1 km, which can resolve large (>1 km2) convective cells. We find that under a given stellar flux, sea surface temperature increases with decreasing gravity. This is because a lower-gravity planet has larger water vapor content and more clouds, resulting in a larger clear-sky greenhouse effect and a stronger cloud warming effect in the small domain. By increasing stellar flux under different gravity values, we find that the convection shifts from a quasi-steady state to an oscillatory state. In the oscillatory state, there are convection cycles with a period of several days, comprised of a short wet phase with intense surface precipitation and a dry phase with no surface precipitation. When convection shifts to the oscillatory state, the water vapor content and high-level cloud fraction increase substantially, resulting in rapid warming. After the transition to the oscillatory state, the cloud net positive radiative effect decreases with increasing stellar flux, which indicates a stabilizing climate effect. In the quasi-steady state, the atmospheric absorption features of CO2 are more detectable on lower-gravity planets because of their larger atmospheric heights. While in the oscillatory state, the high-level clouds mute almost all of the absorption features, making the atmospheric components hard to characterize.
The Hydrodynamic Evolution of Binary Black Holes Embedded within the Vertically Stratified Disks of Active Galactic Nuclei
Authors: Kaaz Nicholas , Schrøder Sophie Lund , Andrews Jeff J. , Antoni Andrea , Ramirez-Ruiz Enrico 
Published: February 2023

Abstract
Stellar-mass black holes can become embedded within the disks of active galactic nuclei (AGNs). Afterwards, their interactions are mediated by their gaseous surroundings. Here, we study the evolution of stellar-mass binary black holes (BBHs) embedded within AGN disks using three-dimensional hydrodynamic simulations and analytic methods, focusing on environments where the AGN disk scale height H is ≳ the BBH sphere of influence. We model the local surroundings of the embedded BBHs using a wind tunnel formalism and characterize different accretion regimes based on the local properties of the disk. We develop prescriptions for accretion and drag for embedded BBHs. Using these prescriptions with AGN disk models that can represent the Toomre-unstable outer regions of AGN disks, we study the long-term evolution of BBHs as they migrate through the disk. We find that BBHs typically merge within ≲1–30 Myr, increasing their mass significantly in the process, allowing BBHs to enter (or cross) the pair-instability supernova mass gap. The BBH accretion rate often exceeds the Eddington limit, sometimes by several orders of magnitude. Many embedded BBHs will merge before migrating significantly in the disk. We also discuss possible electromagnetic signatures during and following the inspiral, finding that it is generally unlikely for the bolometric luminosity of the BBH to exceed the AGN luminosity.
Timing the r-process Enrichment of the Ultra-faint Dwarf Galaxy Reticulum II
Authors: Simon Joshua D. , Brown Thomas M. , Mutlu-Pakdil Burçin , Ji Alexander P. , Drlica-Wagner Alex , Avila Roberto J. , Martínez-Vázquez Clara E. , Li Ting S. , Balbinot Eduardo , Bechtol Keith , Frebel Anna , Geha Marla , Hansen Terese T. , James David J. , Pace Andrew B. , Aguena M. , Alves O. , Andrade-Oliveira F. , Annis J. , Bacon D. , Bertin E. , Brooks D. , Burke D. L. , Rosell A. Carnero , Kind M. Carrasco , Carretero J. , Costanzi M. , da Costa L. N. , De Vicente J. , Desai S. , Doel P. , Everett S. , Ferrero I. , Frieman J. , García-Bellido J. , Gatti M. , Gerdes D. W. , Gruen D. , Gruendl R. A. , Gschwend J. , Gutierrez G. , Hinton S. R. , Hollowood D. L. , Honscheid K. , Kuehn K. , Kuropatkin N. , Marshall J. L. , Mena-Fernández J. , Miquel R. , Palmese A. , Paz-Chinchón F. , Pereira M. E. S. , Pieres A. , Malagón A. A. Plazas , Raveri M. , Rodriguez-Monroy M. , Sanchez E. , Santiago B. , Scarpine V. , Sevilla-Noarbe I. , Smith M. , Suchyta E. , Swanson M. E. C. , Tarle G. , To C. , Vincenzi M. , Weaverdyck N. , Wilkinson R. D. 
Published: February 2023

Abstract
The ultra-faint dwarf galaxy Reticulum II (Ret II) exhibits a unique chemical evolution history, with

72

−
12

+
10

% of its stars strongly enhanced in r-process elements. We present deep Hubble Space Telescope photometry of Ret II and analyze its star formation history. As in other ultra-faint dwarfs, the color–magnitude diagram is best fit by a model consisting of two bursts of star formation. If we assume that the bursts were instantaneous, then the older burst occurred around the epoch of reionization, forming ∼80% of the stars in the galaxy, while the remainder of the stars formed ∼3 Gyr later. When the bursts are allowed to have nonzero durations, we obtain slightly better fits. The best-fitting model in this case consists of two bursts beginning before reionization, with approximately half the stars formed in a short (100 Myr) burst and the other half in a more extended period lasting 2.6 Gyr. Considering the full set of viable star formation history models, we find that 28% of the stars formed within 500 ± 200 Myr of the onset of star formation. The combination of the star formation history and the prevalence of r-process-enhanced stars demonstrates that the r-process elements in Ret II must have been synthesized early in its initial star-forming phase. We therefore constrain the delay time between the formation of the first stars in Ret II and the r-process nucleosynthesis to be less than 500 Myr. This measurement rules out an r-process source with a delay time of several Gyr or more, such as GW170817.
A Study of Primordial Very Massive Star Evolution
Authors: Volpato Guglielmo , Marigo Paola , Costa Guglielmo , Bressan Alessandro , Trabucchi Michele , Girardi Léo 
Published: February 2023

Abstract
We present new evolutionary models of primordial very massive stars with initial masses ranging from 100 to 1000 M
⊙ that extend from the main sequence to the onset of dynamical instability caused by the creation of electron–positron pairs during core C, Ne, or O burning, depending on the star’s mass and metallicity. Mass loss accounts for radiation-driven winds, as well as pulsation-driven mass loss on the main sequence and during the red supergiant phase. After examining the evolutionary properties, we focus on the final outcome of the models and associated compact remnants. Stars that avoid the pair instability supernova channel should produce black holes with masses ranging from ≈40 to ≈1000 M
⊙. In particular, stars with initial masses of about 100 M
⊙ could leave black holes of ≃85–90 M
⊙, values consistent with the estimated primary black hole mass of the GW190521 merger event. Overall, these results may contribute to explaining future data from next-generation gravitational-wave detectors, such as the Einstein Telescope and Cosmic Explorer, which will have access to an as-yet-unexplored black hole mass range of ≈102–104
M
⊙ in the early universe.
Massive Molecular Gas Companions Uncovered by Very Large Array CO(1–0) Observations of the z = 5.2 Radio Galaxy TN J0924−2201
Authors: Lee Kianhong , Kohno Kotaro , Hatsukade Bunyo , Egusa Fumi , Yamashita Takuji , Schramm Malte , Ichikawa Kohei , Imanishi Masatoshi , Izumi Takuma , Nagao Tohru , Toba Yoshiki , Umehata Hideki 
Published: February 2023

Abstract
We present Karl G. Jansky Very Large Array K-band (19 GHz) observations of the redshifted CO(1–0) line emission toward the radio galaxy TN J0924−2201 at z = 5.2, which is one of the most distant radio galaxies with CO detected. With an angular resolution of ∼2″, the CO(1–0) line emission is resolved into three clumps, within ±500 km s−1 relative to its redshift, which is determined by Lyα. We find that the clumps are located off-center and 12–33 kpc away from the center of the host galaxy, which has counterparts in the Hubble Space Telescope i band, Spitzer/IRAC, and the Atacama Large Millimeter/submillimeter Array (ALMA) band 6 (230 GHz; 1.3 mm). With the ALMA detection, we estimate the infrared luminosity L
IR and the star formation rate (SFR) of the host galaxy to be (9.3 ± 1.7) × 1011
L
⊙ and 110 ± 20 M
⊙ yr−1, respectively. We also derive the 3σ upper limit of

M

H

2

<
1.3
×

10

10

M
⊙ at the host galaxy. The detected CO(1–0) line luminosities of the three clumps,

L

′

CO
(
1
−
0
)

= (3.2–4.7) × 1010 K km s−1 pc2, indicate the presence of three massive molecular gas reservoirs, with

M

H

2

= (2.5–3.7) × 1010
M
⊙, assuming a CO-to-H2 conversion factor of α
CO = 0.8

M

⊙

(
K

km

s

−
1

pc

2

)

−
1

, although the SFR is not elevated due to the nondetection of the ALMA 1.3 mm continuum (SFR < 40 M
⊙ yr−1). From the host galaxy, the nearest molecular gas clump, labeled “clump A,” is apparently in alignment with the radio jet axis, showing radio–CO alignment. The origins of these three clumps around TN J0924–2201 can possibly be interpreted as outflows, mergers, or jet-induced metal enrichment.
Labor Migrants at Risk: Formal and Informal Insurance Strategies among Central Asians in Moscow
Authors: Pellet Sandra , Talancé Marine de 
Published: February 2023

This article studies formal and informal risk-mitigating practices among Central Asian labor migrants in Moscow. The migration context is inherently uncertain, implying that migrants may try to protect themselves against potential risks by resorting to insurance mechanisms. However, migration is a unique situation that raises a number of questions. First of all, do formal protective institutions or insurance markets exist in the country of arrival? Secondly, if state or market insurance schemes exist, are they accessible to all migrants? What do at-risk labor migrants do when they cannot rely on formal schemes? Central Asian people are used to relying on social networks and informal practices in their home country. Previous articles have shown that these informal networks may be transposed in a migratory context, suggesting that informal risk-mitigating practices can be a substitute for formal insurance schemes and act as a social safety net for precarious migrants not covered by social security or insurance contracts. In this paper, we investigate the relationship between informal and formal insurance schemes and whether these can act as a substitute or complement among Tajikistani and Uzbekistani migrants, based on a survey of 1,213 labor migrants in Moscow.
Médias audiovisuels et diasporas africaines en France : des enjeux de la représentation aux défis de la production
Authors: Jedlowski Alessandro 
Published: February 2023

Ce texte propose un bilan des études menées les vingt dernières années sur la présence des diasporas africaines sur les écrans français, mettant prioritairement l’accent sur les études qui s’intéressent aux médias audiovisuels de divertissement (émissions de télévision, films, séries). Il propose une réflexion basée sur la prise en compte combinée de trois différentes approches : l’analyse de contenus (dominante dans les recherches publiées jusqu’à aujourd’hui), l’étude des pratiques de réception mises en place par les minorités, et l’étude de la place de ces groupes dans les processus de production. La question de présences noires à l’écran reste d’actualité encore aujourd’hui, et un des objectifs du bilan présenté ici est d’ouvrir l’espace à l’émergence de nouvelles recherches capable d’affiner notre compréhension des spécificités historiques et politiques du contexte français, sur la base d’une connaissance approfondie des réflexions déjà proposées par d’autres chercheurs, et de leurs zones d’ombre.
Comparative Evaluation of Various Parameters of Spontaneous Smile Captured by Conventional Photographic Method, Video Clip Method, and Direct Biometric Method
Authors: Shah Romilkumar 
Published: February 2023

Introduction:
Facial and dental attractiveness can significantly impact one's life. As per Kiekens, smile esthetics contributed 25%–31% to facial attractiveness. Smile is one of the most effective means by which people convey their emotions. People have more positive acceptance and better behavior against attractive faces; this phenomenon is called “attractiveness halo”. The records needed for contemporary smile visualization and quantification can be static records (static photograph and/or lateral cephalogram), dynamic record (digital videography), and direct biometric/clinical measurements. Previous studies examining smile esthetics had used static photographs. Recently, a method of capturing and analyzing the smile using videography and computer software becomes need of an hour.

Aim:
Comparative evaluation of various parameters of spontaneous smile captured by conventional photography method (CPM), video clip method (VCM), and direct biometric method (DBM).

Materials and Methods:
The subjects were screened clinically and based on normal soft tissue profile angle in the profile photographs. Smile photographs of the subjects were obtained using conventional photography technique. VCM was used to capture spontaneous smiles of the subjects using the same camera. Finally, the parameters of the smile were directly measured on the subjects using Vernier calipers. Images were standardized and subjected to appropriate analyses to evaluate smile arc, buccal corridor, lower incisal display, upper gingival display, smile index, Morley's ratio, and smile line.

Results:
Measurements of smile arc, buccal corridor, lower incisal display, upper gingival display, smile index, Morley's ratio, and smile line on the photographs obtained from CPM showed statistically significant differences when compared to both VCM and DBM.

Conclusion:
As VCM is better able to capture and assess spontaneous smile when compared to CPM, it is the preferred method along with DBM as additional confirmation.
Perinatal Outcome of Subchorionic Hemorrhage in Early Pregnancy Vaginal Bleeding
Authors: Gupta Manisha , Agarwal Neelima , Agrawal Alpana 
Published: February 2023

Introduction:
First-trimester vaginal bleeding is an early indicator of underlying placental pathology and is a causative factor for adverse perinatal outcome. Although subchorionic hemorrhage is quite prevalent, but outcomes have not been studied in the ongoing pregnancies. Hence, we aimed to study the outcome in pregnancies with subchorionic hemorrhage presenting with vaginal bleeding in up to 20 weeks of pregnancy.

Methodology:
The present study was an observational study conducted over a period of 1 year. A sample size of 230 patients presenting with threatened abortion within 20 weeks of gestation and who fulfilled the inclusion criteria were recruited in the study. A routine ultrasound examination was done to analyze the presence of subchorionic hemorrhage, and the outcomes of such pregnancies were studied.

Results:
Total 230 subjects presented with bleeding in early pregnancy with gestational age of <20 weeks on ultrasound examination; 31 (13.4%) patients were found to have subchorionic hemorrhage. The present study showed that women with subchorionic hematoma had a significantly higher rate of complications.

Conclusion:
There is an increased risk of adverse outcome in pregnancy with subchorionic hemorrhage.
A Cross-Sectional Study to Assess Nutritional Status of Adolescent Girls Using Body Mass Index
Authors: Jain Ashutosh , Raje Vaishali Vinayak , Kakade Satish V. 
Published: February 2023

Background:
Malnutrition continues to be a major public health problem worldwide. World's attention is now toward malnourished girls who are more likely to remain undernourished during adolescence and adulthood, and when pregnant, they are more likely to deliver low birth-weight babies creating a vicious cycle.

Objectives:
(1) To study sociodemographic profile of adolescent girls and (2) to study the association of undernutrition with sociodemographic status.

Materials and Methods:
This school-based cross-sectional study was conducted among 268 adolescent girls of 7th and 8th standard, from government high school of Karad. Quantitative data were analyzed using SPSS version 20 for calculating mean with standard deviation and Chi-square test was applied.

Results:
According to body mass index for age, the prevalence of undernutrition was 32.85%. Similarly undernutrition was found high among rural girls (35.4%), among girls of age group 12 (34.85%) and those who were pure vegetarian (37.3%). It was found very much high among three generation type family (45%). Significantly high proportion of girls with first birth order (38.3%), below poverty line (BPL) families (71.4%), and the girls taking <3 meals per day (76.1%), were found to be undernourished. Skipping breakfast for 1-3 days per week (27.3%) and the girls using fast food (98.9%) as well as soft drinks (56.8%) showed high rate of undernutrition.

Conclusion:
Undernutrition was found to be prevalent among the rural adolescent girls with first birth order belonging to BPL families and associated with poor dietary habits.
Evaluating the Efficacy of Innovative Coding System for Ceramic Restorations
Authors: Kambala Seema Sathe , Godbole Surekha , Borle Anjali Bhoyar , Dhamande Mithilesh M , Kambala Rajanikanth , Jaiswal Tanvi 
Published: February 2023

Background:
Forensic odontology has evolved with the evolution of mankind. Since ages it has been of our interest to identify the dead. Because of events beyond our control many human beings may not die a natural death or in familiar surroundings. The task of identifying these individuals is of paramount importance in forensic odontology.

Method:
A Quick response code of minimum dimension was customized and incorporated into e max lithium disilicate restorations. Restorations are fabricated in such a way that it can scanned using mobile software and displays aadhar number of patient, which ultimately helps in forensic identification.

Result:
This coded prosthesis helps in the identification of individuals.

Conclusion:
Code used in present study was readable in most of the ceramic restorations and maintains its sustainability in all the conditions under which it was tested.