bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two Candidates for Dual AGN in Dwarf-dwarf Galaxy Mergers
Authors: Mićić Marko , Holmes Olivia J. , Wells Brenna N. , Irwin Jimmy A. 
Published: February 2023

Abstract
Dual active galactic nuclei (DAGN) are important for understanding galaxy-merger-triggered fueling of black holes and the hierarchical growth of structures. The least explored type of DAGN are those associated with mergers of two dwarf galaxies. According to observations and cosmological simulations, dwarf galaxies are the most abundant type of galaxies in the early universe and the galaxy-merger rate is dominated by dwarfs. However, these mergers are generally too distant to be directly observed, and low-redshift dwarf-dwarf merger-related DAGN are notoriously hard to find. In this paper, we present the first results of our large-scale search for this elusive type of object and the first two candidates for DAGN in dwarf-dwarf mergers. Both objects exhibit tidal features (tails and bridges) characteristic of galaxy mergers/interactions. One object is apparently in a late-stage merger with an AGN separation of <5 kpc, while the second is in an early-stage merger with interacting galaxies having established a tidal bridge. Both objects have dual, luminous X-ray sources that are most likely due to actively accreting massive black holes. Also, both objects have infrared counterparts, with colors consistent with being AGN. Follow-up observations will provide us a glimpse into key processes that govern the earliest phases of growth of galaxies, their central black holes, and merger-induced star formation.
Magnetic Flux Transport in Radiatively Inefficient Accretion Flows and the Pathway toward a Magnetically Arrested Disk
Authors: Dhang Prasun , Bai Xue-Ning , White Christopher J. 
Published: February 2023

Abstract
Large-scale magnetic fields play a vital role in determining the angular momentum transport and generating jets/outflows in accreting systems, yet their origins remain poorly understood. We focus on radiatively inefficient accretion flows (RIAFs) around black holes (BHs), and conduct 3D general-relativistic magnetohydrodynamic simulations using the Athena++ code. We first reconfirm that the magnetorotational instability driven dynamo in the RIAF alone does not spontaneously form a magnetically arrested disk (MAD), conducive for strong-jet formation. We next investigate the other possibility, where the large-scale magnetic fields are advected inward from external sources (e.g., the companion star in X-ray binaries and the magnetized ambient medium in active galactic nuclei). Although the actual configurations of the external fields could be complex and uncertain, they are likely to be closed. As a first study, we treat them as closed field loops of different sizes, shapes, and field strengths. Unlike earlier studies of flux transport, where the magnetic flux is injected into the initial laminar flow, we inject the magnetic field loops into the quasi-stationary turbulent RIAF in inflow equilibrium, then follow their evolution. We find that a substantial fraction (∼15%–40%) of the flux injected at large radii reaches the BH, with a weak dependence on the loop parameters, except when the loops are injected at high latitudes, away from the midplane. The relatively high efficiency of the flux transport observed in our study hints that a MAD might easily be formed relatively close to the BH, provided that a source of the large-scale field exists at larger radii.
On the Connection between Rieger-type and Magneto-Rossby Waves Driving the Frequency of the Large Solar Eruptions during Solar Cycles 19–25
Authors: Korsós Marianna B. , Dikpati Mausumi , Erdélyi Robertus , Liu Jiajia , Zuccarello Francesca 
Published: February 2023

Abstract
Global solar activity variation mainly occurs over about an 11 yr cycle. However, both longer and shorter periodicities than the solar cycle are also present in many different solar activity indices. The longer timescales may be up to hundreds of years, while the shorter timescales for global solar variability could be within 0.5–2 yr, which include, e.g., from the Rieger-type periods (150–160 days) to quasi-biennial oscillations of 2 yr. The most likely origin of this short-timescale quasi-periodicity is attributed to magnetic Rossby waves, which have periods of 0.8–2.4 yr. In this work, we present findings of a unique evolution of identified shorter periodicities, like the Rieger-type, arising from magnetic Rossby waves, throughout Solar Cycles 19–25. We report further observational evidence of the strong relationship between the Rieger-type periodicity, magneto-Rossby waves, and major solar flare activity. Moreover, this study also reveals that the global solar magnetic field has a continuous periodic longitudinal conveyor belt motion along the solar equator, together with an up-and-down movement in the latitudinal directions. We found that when these longitudinal and latitudinal movements have Rieger-type periodicity and magneto-Rossby waves during the same period of a solar cycle, major flare activity is present.
GRB 221009A: A Light Dark Matter Burst or an Extremely Bright Inverse Compton Component?
Authors: González M. M. , Avila Rojas D. , Pratts A. , Hernández-Cadena S. , Fraija N. , Alfaro R. , Pérez Araujo Y. , Montes J. A. 
Published: February 2023

Abstract
Gamma-ray bursts (GRBs) have been considered as potential very high energy photon emitters due to the large amount of energy released as well as the strong magnetic fields involved in their jets. However, the detection of teraelectronvolt photons is not expected from bursts beyond a redshift of z ≳ 0.1, due to their attenuation with the extragalactic background light (EBL). For these reasons, the recent observation of photons with energies of 18 and 251 TeV from GRB 221009A (z = 0.151) last 2022 October 9 has challenged what we know about the teraelectronvolt-emission mechanisms and the extragalactic background. In order to explain the teraelectronvolt observations, recent works exploring candidates of dark matter have started to appear. In this paper, we discuss the required conditions and limitations within the most plausible scenario, synchrotron self-Compton radiation in the GRB afterglow, to interpret the one 18 TeV photon observation besides the EBL. To avoid the Klein–Nishina effect, we find an improbable value of the microphysical magnetic parameter below 10−6 for a circumburst medium value >1 cm−3 (expected in the collapsar scenario). Therefore, we explore possible scenarios in terms of axion-like particles (ALPs) and dark photon mechanisms to interpret this highly energetic photon and we discuss the implications in the GRB energetics. We find that the ALPs and dark photon scenarios can explain the 18 teraelectronvolt photon but not the 251 teraelectronvolt photon.
The Similar Seven: A Set of Very Alike Exoplanets to Test Correlations between System Parameters and Atmospheric Properties
Authors: McGruder Chima D. , López-Morales Mercedes , Brahm Rafael , Jordán Andrés 
Published: February 2023

Abstract
Studies of exoplanetary atmospheres have found no definite correlations between observed high-altitude aerosols and other system parameters. This could be, in part, because of the lack of homogeneous exoplanet samples for which specific parameters can be isolated and inspected. Here, we present a set of seven exoplanets with very similar system parameters. We analyze existing photometric time series, Gaia parallax, and high-resolution spectroscopic data to produce a new set of homogeneous stellar, planetary, and orbital parameters for these systems. With this, we confirm that most measured parameters for all systems are very similar, except for the host stars’ metallicities and possibly high-energy irradiation levels, which require UV and X-ray observations to constrain. From the sample, WASP-6b, WASP-96b, and WASP-110b have observed transmission spectra that we use to estimate their aerosol coverage levels using the Na i doublet 5892.9 Å. We find a tentative correlation between the metallicity of the host stars and the planetary aerosol levels. The trend we find with stellar metallicity can be tested by observing transmission spectra of the remaining planets in the sample. Based on our prediction, WASP-25b and WASP-55b should have higher levels of aerosols than WASP-124b and HATS-29b. Finally, we highlight how targeted surveys of alike planets similar to the ones presented here might prove key for identifying driving factors for atmospheric properties of exoplanets in the future and could be used as a sample selection criterion for future observations with, e.g., JWST, ARIEL, and the next generation of ground-based telescopes.
A Cosmological Fireball with 16% Gamma-Ray Radiative Efficiency
Authors: Li Liang , Wang Yu , Ryde Felix , Pe’er Asaf , Zhang Bing , Guiriec Sylvain , Castro-Tirado Alberto J. , Kann D. Alexander , Axelsson Magnus , Page Kim , Veres Péter , Bhat P. N. 
Published: February 2023

Abstract
Gamma-ray bursts (GRBs) are the most powerful explosions in the universe. How efficiently the jet converts its energy to radiation is a long-standing problem, which is poorly constrained. The standard model invokes a relativistic fireball with a bright photosphere emission component. A definitive diagnosis of GRB radiation components and the measurement of GRB radiative efficiency require prompt emission and afterglow data, with high resolution and wide band coverage in time and energy. Here, we present a comprehensive temporal and spectral analysis of the TeV-emitting bright GRB 190114C. Its fluence is one of the highest for all the GRBs that have been detected so far, which allows us to perform a high-resolution study of the prompt emission spectral properties and their temporal evolutions, down to a timescale of about 0.1 s. We observe that each of the initial pulses has a thermal component contributing ∼20% of the total energy and that the corresponding temperature and inferred Lorentz factor of the photosphere evolve following broken power-law shapes. From the observation of the nonthermal spectra and the light curve, the onset of the afterglow corresponding to the deceleration of the fireball is considered to start at ∼6 s. By incorporating the thermal and nonthermal observations, as well as the photosphere and synchrotron radiative mechanisms, we can directly derive the fireball energy budget with little dependence on hypothetical parameters, measuring a ∼16% radiative efficiency for this GRB. With the fireball energy budget derived, the afterglow microphysics parameters can also be constrained directly from the data.
La santé comme domaine du développement : un panorama historico-critique
Authors: Ridde Valery , Boidin Bruno 
Published: February 2023

Cet entretien analyse la façon dont la thématique de la santé a été abordée dans la revue Mondes en développement et propose une perspective critique des modèles dominants de l’aide dans le domaine de la santé. Au regard des quarante dernières années, la permanence de certaines idées, malgré leur caractère discutable, est mise en évidence. Les échecs des paradigmes dominants et des dispositifs associés n’ont pas débouché sur de véritables réorientations des politiques de santé. Derrière cette réalité sont mis au jour des intérêts stratégiques du côté des experts et des institutions. Pourtant, quelques perspectives se dégagent à travers les expériences de terrain innovantes et l’évaluation réaliste des leviers de réussite et des obstacles rencontrés par les programmes. Classification JEL : O15, O21, O55, I15
A dialogue on the future of microfinance and international development
Authors: Labie Marc , Morduch Jonathan 
Published: February 2023

Dans ce dialogue, Jonathan Morduch est interviewé par Marc Labie pour identifier les défis qui doivent être affrontés par les politiques en matière de microfinance et d’inclusion financière. Au cours des 50 dernières années, la microfinance a parfois été surestimée, parfois sous-estimée. Ce qui a été appris durant cette période, c’est que les opinions trop simplistes sont souvent peu concluantes. Les politiques et les pratiques en matière d’inclusion financière ont un rôle à jouer pour aider les familles pauvres à affronter les défis de la vie quotidienne. En passant en revue l’histoire récente du secteur de la microfinance, ce dialogue tente d’identifier les questions clés qu’il faut garder à l’esprit pour atteindre cet objectif. Classification JEL : G23, O16, O17
La règlementation de la microfinance : historique, portée et limites dans l’espace UEMOA
Authors: Acclassato Houensou Denis 
Published: February 2023

La réglementation des activités de microfinance dans les années 90 dans l’espace UEMOA est apparue nécessaire avec l’apparition et le développement rapide des structures spécialisées dans la petite épargne et le microcrédit. Elle a permis la mise en place des instances de surveillance, de contrôle et de supervision, de même qu’un renforcement des sanctions pénales et financières des acteurs du secteur. Parallèlement, un accompagnement et un suivi des institutions de microfinance existantes ou autorisées ont été mis en place dans chaque État-membre par les ministres en charge des Finances et des Affaires sociales. Cet article présente l’historique et les dispositions réglementaires en vigueur, ainsi que les réformes nécessaires à une protection accrue des activités de microfinance dans l’espace. Classification JEL : K22, K24, G18, G21, G28, L51
Introduction
Authors: Combeau Yvan , Daniel Justin 
Published: February 2023

Ce dossier propose à partir de plusieurs études (Antilles, La Réunion, Pacifique) une écriture de l’histoire des départementalisations et des évolutions ultramarines « de l’uniformité à la différenciation ». Les articles interrogent les contextes politiques et les mises en œuvre de cette réforme fondatrice, acte fondateur voté par la première Assemblée Constituante (19 mars 1946). À partir des analyses de cette « décolonisation intra-française », les textes soulignent le fossé qui se creuse sous la IV e République entre les attentes teintées d’impatience exprimées localement à l’aune des espoirs suscités et l’absence de concrétisation des objectifs d’égalité sociale. Ce dossier démontre combien les débats sur les départementalisations et les devenirs institutionnels résonnent et demeurent présents dans l’histoire du temps présent des outre-mer français.
Correlation of transthoracic echocardiography-derived pulmonary to systemic flow ratio with hemodynamically estimated left to right shunt in atrial septal defects
Authors: Faherty Erin , Rajagopal Hari , Lee Simon , Love Barry , Srivastava Shubhika , Parness Ira A. , Uppu Santosh C. 
Published: February 2023

ABSTRACT

Background:
Transthoracic echocardiographic (TTE) estimation of the pulmonary to systemic flow ratio (Qp/Qs) is routinely used in clinical practice and is included in the American Society of Echocardiography Guidelines. We sought to assess its real-world applicability with a particular focus on hemodynamically significant shunt lesions.

Methods:
Retrospective single institutional review of TTE's in patients with secundum atrial septal defect prior to cardiac catheterization (cath) from 2012 to 2018 was performed (n = 109), those with technically limited images for Qp/Qs calculation (n = 11) and those with time interval between TTE and cath >60 days were excluded (n = 14). Qp/Qs was calculated from stored clips by previously described methods and correlated with those obtained by oximetry. Patients were subdivided into two age groups <21 (Group 1) and ≥22 years (Group 2). TTE and cath methods for Qp/Qs estimation were compared using paired t-test, Pearson's correlation coefficient, and Bland–Altman plots.

Results:
Eighty-four subjects met inclusion criteria (age range 3–78 years). Group 1 n = 35; median age 10 years; Group 2 n = 49; median age 49 years. Transthoracic echocardiogram was performed 19.5 ± 15 days prior to cath. Mean Qp/Qs derived by cath and TTE were 2.09 ± 0.9 versus 2.54 ± 1.2 (P < 0.0001). Overall correlation was poor between the methods (r
2 = 0.32, P < 0.0001) and continued to be poor for Groups 1 and 2 (r
2= 0.24, P = 0.003 and r
2= 0.40, P < 0.0001 respectively). Bland–Altman plots demonstrated poor agreement between the predetermined limits of agreement (-0.5–1.5).

Conclusion:
Transthoracic echocardiography estimated Qp/Qs, although routinely utilized in clinical practice, has poor correlation and agreement with oximetry-derived Qp/Qs. The test performs poorly in all age groups in detecting a hemodynamically significant shunt and tends to overestimate the degree of left to right shunt.
Association between pulmonary vein stenosis and necrotizing enterocolitis or gastrointestinal pathology
Authors: Duchon Jennifer , Farkouh-Karoleski Christiana , Bailey Dominique D. , Krishnan Usha S. 
Published: February 2023

ABSTRACT

Objective:
Pulmonary vein stenosis (PVS) is an emerging cause of pulmonary hypertension in preterm infants. It is an often lethal condition with poor long.term prognosis and high mortality. Previous work suggests an association between necrotizing enterocolitis (NEC) and PVS, supporting a possible role for inflammatory processes due to gastrointestinal (GI) pathology as an associated risk factor for PVS.

Study Description:
We performed a matched case–control study where infants with PVS were matched for gestational age with infants without PVS. Hospital records were reviewed for prior history of NEC or other gut pathology.

Results:
Twenty-four PVS patients were matched with 68 controls; 63% of patients (15/24) had prior GI pathology as opposed to 19% (13/68) of controls. The GI pathology group had a significantly higher growth restriction and C-reactive protein. The mean gradient across the pulmonary veins was higher in the gut pathology group versus controls, as was mortality (29% vs. 9%).

Conclusions:
The previously described association between PVS and intestinal pathology was further strengthened by this study. The presence of GI pathology should lead to early surveillance and intervention for PVS.
Coxsackie B viral infection presenting with hemorrhagic pericardial effusion and pleural effusion
Authors: Maram Krishna Prasad , Kudumula Vikram , Paturi Venkata Rama Rao 
Published: February 2023

ABSTRACT
We report an 11-year-old female child presenting with hemorrhagic pericardial effusion causing cardiac tamponade along with moderate left ventricular dysfunction, who screened positive for Coxsackie B infection in the setting of cough, shortness of breath, and chest pain. She needed emergency pericardiocentesis. She also had massive bilateral hemorrhagic pleural effusions requiring bilateral chest drains placement. With a presumed diagnosis of acute myopericarditis, she was treated with steroids and ibuprofen. She made a full recovery without any further recurrence of pericardial or pleural effusion.
Thrombosis of aneurysmal pulmonary arteries in patent ductus arteriosus with Eisenmenger syndrome
Authors: Bhattacharya Deepanjan , Sasikumar Deepa , Kurup KN Harikrishnan , Anoop Ayyappan , Gaddamedi Sravan Kumar 
Published: February 2023

ABSTRACT
A 45-year-old lady with patent ductus arteriosus with Eisenmenger's syndrome had presented with hemoptysis. Computed tomography revealed aneurysmally dilated pulmonary arteries with a large calcified organized thrombus.
Isolated ostial left main coronary artery stenosis causing ischemic cardiomyopathy in a child with bicuspid aortic valve
Authors: Chohan Amad , Abraham Carol J. , Ward Kent , Ponniah Kumar , Salkini Anas , Burkhart Harold M. , Mir Arshid 
Published: February 2023

ABSTRACT
Bicuspid aortic valve (BAV) is the most common congenital cardiac defect, commonly associated with valve dysfunction and coarctation of aorta. Rarely, BAV can be associated with abnormalities of the coronary arteries, the most common of which are ectopic coronary origins. In this report, we present a case of a 2-year-old child with BAV, without coexisting supravalvular aortic stenosis, who was found to have a left main coronary ostio-proximal stenosis, leading to ischemic cardiomyopathy and congestive heart failure.
Estimating Center of Rotation of Single-Photon Emission Computerized Tomography Projection Images Using MATLAB for Standardization and Calibration
Authors: Pandey Anil Kumar , Chaudhary Jagrati , Kaur Gagandeep , Yadav Priya , Sharma Param Dev , Patel Chetan , Kumar Rakesh 
Published: February 2023

Objective:
The objective of the study was to develop a Personal Computer (PC) based tool to estimate the center of rotation (COR) offsets from COR projection datasets using methods mentioned in IAEA-TECDOC-602.

Materials and Methods:
Twenty-four COR studies were acquired on Discovery NM 630 Dual head gamma camera fitted with parallel hole collimator, and COR offsets were estimated with the software available at the terminal for processing a COR study. These COR projection images were exported in DICOM. A MATLAB script (software program) was written to estimate COR offset using Method A (using opposite pair of projections) and Method B (using curve fitting method) as mentioned in IAEA-TECDOC-602. Our program read the COR study (in DICOM) and estimated COR offsets using Method A and Method B. The accuracy of the program was verified using simulated projection dataset of a point source object acquired at 6° interval in the range of 0°–360° angle. Bland Altman plot was used for analyzing the agreement between the COR offsets estimated using (1) Method A and Method B mentioned in IAEA-TECDOC-602, and (2) Our program and vendor program available at Discovery NM 630 acquisition terminal.

Results:
On simulated data, offset from center of gravity (COG) in X direction (COGX) and COG in Y direction (COGY) estimated using Method A was constant (same) at each pair of angles while using Method B, it was found to be in the range (−2 × 10−10, 1 × 10−10) which is negligible. Most of the differences (23 out of 24) between the result of Method A and Method B, and between the results of our program and vendor program was found to be within 95% confidence interval (mean ± 1.96 standard deviation).

Conclusions:
Our PC-based tool to estimate COR offsets from COR projection datasets using methods mentioned in IAEA-TECDOC-602 was found to be accurate and provides results in agreement with vendor's program. It can be used as an independent tool to estimate COR offset for standardization and calibration purposes.
Evaluation of New Tracers in the Identification of Sentinel Lymph Node in Patients with Early Breast Cancer
Authors: Srivastava Anurag , Goyal Amit , Seenu Vuthaluru , Kumar Rakesh 
Published: February 2023

Purpose:
Sentinel node mapping is the standard of care for evaluation of axilla for women with early node negative breast cancer. Validation of a new tracer for sentinel node biopsy requires full axillary lymph node dissection to establish its performance indicators. This exposes about 70% of women to unnecessary axillary dissection with its attendant morbidity.

Aims and Objective:
To investigate the predictive value of identification of sentinel lymph nodes by a tracer for knowing its sensitivity and false-negative rates (FNR).

Methods:
A linear regression on data from a network meta-analysis was carried out, and the correlation between identification and sensitivity and its predictive value were ascertained.

Results:
A strong linear relationship was observed between identification and sensitivity of sentinel node biopsy (correlation coefficient r = 0.97). The sensitivity and false negativity can be predicted by the identification rate. An identification rate of 93% corresponds to sensitivity = 90.51% and a FNR = 9.49%. The current literature on newer tracers has been succinctly reviewed.

Conclusion:
The linear regression demonstrated a very high predictive value of identification rate for ascertaining the sensitivity and FNRs of sentinel node biopsy. A new tracer for sentinel node biopsy can be introduced in clinical practice, if it achieves an identification rate of 93% or more.