bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uniform Forward-modeling Analysis of Ultracool Dwarfs. II. Atmospheric Properties of 55 Late-T Dwarfs
Authors: Zhang 张周 Zhoujian 健 , Liu Michael C. , Marley Mark S. , Line Michael R. , Best William M. J. 
Published: November 2021

Abstract
We present a large uniform forward-modeling analysis for 55 late-T (T7–T9) dwarfs, using low-resolution (R ≈ 50–250) near-infrared (1.0–2.5 μm) spectra and cloudless Sonora–Bobcat model atmospheres. We derive the objects’ effective temperatures, surface gravities, metallicities, radii, masses, and bolometric luminosities using our newly developed Bayesian framework, and use the resulting population properties to test the model atmospheres. We find (1) our objects’ fitted metallicities are 0.3–0.4 dex lower than those of nearby stars; (2) their ages derived from spectroscopic parameters are implausibly young (10 Myr–0.4 Gyr); (3) their fitted effective temperatures show a similar spread to empirical temperature scales at a given spectral type but are ∼50–200 K hotter for ≥T8 dwarfs; and (4) their spectroscopically inferred masses are unphysically small (mostly 1–8 M
Jup). These suggest the Sonora–Bobcat assumptions of cloudless and chemical-equilibrium atmospheres do not adequately reproduce late-T dwarf spectra. We also find a gravity and metallicity dependence of effective temperature as a function of spectral type. Combining the resulting parameter posteriors of our sample, we quantify the degeneracy between the fitted surface gravity and metallicity such that an increase in Z combined with a 3.4× increase in logg results in a spectrum that has similar fitted parameters. We note the systematic difference between the late-T dwarf spectra and Sonora–Bobcat models is on average ≈2%–4% of the objects’ peak J-band fluxes over the 1.0–2.5 μm range, implying modeling systematics will exceed measurement uncertainties when analyzing data with J-band S/N ≳ 50. Using our large, high-quality sample, we examine the spectral-fitting residuals as a function of wavelength and atmospheric properties to discern how to improve the model assumptions. Our work constitutes the largest analysis of brown dwarf spectra using multimetallicity models and the most systematic examination of ultracool model atmospheres to date.
Solar Origin of Bare Ion Anomalies in the Solar Wind and Interplanetary Coronal Mass Ejections
Authors: Rivera Yeimy J. , Lepri Susan T. , Raymond John C. , Reeves Katharine K. , Stevens Michael L. , Zhao Liang 
Published: November 2021

Abstract
Previous studies of the solar wind and interplanetary coronal mass ejections (ICMEs) have shown periods throughout solar cycle 23 when heliospheric measurements of ion composition appear anomalous. In these cases, C6+ and other bare ion densities, i.e., fully stripped ions, are unusually low, leading it to be classified as the Outlier solar wind. However, its origin and solar source(s) remain largely uncertain. In this work, we further characterize the Outlier wind to connect its heliospheric structure to its solar source to constrain the conditions of its formation. Through an analysis of the plasma and magnetic field properties of each occurrence between 1998 and 2011, we find that the Outlier plasma occurs in the slow solar wind or interplanetary mass ejections (∼460 km s−1), and comprises distinct, high density events lasting less than 10 hr. The number of events is correlated with the solar cycle, indicating the process leading to the depletion of bare ions is strongly governed by the magnetic field. Additionally, the events exhibit a bi- or unidirectional suprathermal electron strahl that is concurrent with changes in the magnetic field direction. Moreover, the Outlier wind’s composition, entropy, Alfvén speed, and proton temperature suggest a helmet streamer or active region origin. Together, the properties exhibited by the Outlier wind suggest a strong connection to the heliospheric current sheet and that the solar wind events are smaller scale versions of those seen in ICMEs, such as small magnetic flux ropes. However, more work is necessary to determine the source and creation process in the vicinity of the Sun.
Emission of Magnetar Bursts and Precursors of Neutron Star Mergers
Authors: Beloborodov Andrei M. 
Published: November 2021

Abstract
Magnetar bursts can be emitted by Alfvén waves growing in the outer magnetosphere to nonlinear amplitudes, δ
B/ B ∼ 1, and triggering magnetic reconnection. Similar magnetic flares should occur quasi-periodically in a magnetized neutron star binary nearing merger. In both cases, fast dissipation in the magnetic flare creates optically thick e
± plasma, whose heat capacity is negligible compared with the generated radiation energy. Magnetic dissipation then involves photon viscosity and acts through Compton drag on the plasma bulk motions in the reconnection region. The effective temperature of the resulting Comptonization process is self-regulated to tens of keV. The generated X-ray emission is calculated using time-dependent radiative transfer simulations, which follow the creation of e
± pairs and the production, Comptonization, and escape of photons. The simulations show how the dissipation region becomes dressed in an e
± coat and how the escaping spectrum is shaped by radiative transfer through the coat. The results are compared with observed magnetar bursts, including the recent activity of SGR 1935+2154 accompanied by a fast radio burst. Predictions are made for X-ray precursors of magnetized neutron star mergers.
The Solar Memory from Hours to Decades
Authors: Aschwanden Markus J. , Johnson Jay R. 
Published: November 2021

Abstract
Waiting-time distributions allow us to distinguish at least three different types of dynamical systems, including (i) linear random processes (with no memory); (ii) nonlinear, avalanche-type, nonstationary Poisson processes (with memory during the exponential growth of the avalanche rise time); and (iii) chaotic systems in the state of a nonlinear limit cycle (with memory during the oscillatory phase). We describe the temporal evolution of the flare rate λ(t) ∝ t

p
with a polynomial function, which allows us to distinguish linear (p ≈ 1) from nonlinear (p ≳ 2) events. The power-law slopes α of the observed waiting times (with full solar cycle coverage) cover a range of α = 2.1–2.4, which agrees well with our prediction of α = 2.0 + 1/p = 2.3–2.6. The memory time can also be defined with the time evolution of the logistic equation, for which we find a relationship between the nonlinear growth time τ

G
= τ
rise/(4p) and the nonlinearity index p. We find a nonlinear evolution for most events, in particular for the clustering of solar flares (p = 2.2 ± 0.1), partially occulted flare events (p = 1.8 ± 0.2), and the solar dynamo (p = 2.8 ± 0.5). The Sun exhibits memory on timescales of ≲2 hr to 3 days (for solar flare clustering), 6–23 days (for partially occulted flare events), and 1.5 month to 1 yr (for the rise time of the solar dynamo).
Molecules with ALMA at Planet-forming Scales (MAPS). III. Characteristics of Radial Chemical Substructures
Authors: Law Charles J. , Loomis Ryan A. , Teague Richard , Öberg Karin I. , Czekala Ian , Andrews Sean M. , Huang Jane , Aikawa Yuri , Alarcón Felipe , Bae Jaehan , Bergin Edwin A. , Bergner Jennifer B. , Boehler Yann , Booth Alice S. , Bosman Arthur D. , Calahan Jenny K. , Cataldi Gianni , Cleeves L. Ilsedore , Furuya Kenji , Guzmán Viviana V. , Ilee John D. , Le Gal Romane , Liu Yao , Long Feng , Ménard François , Nomura Hideko , Qi Chunhua , Schwarz Kamber R. , Sierra Anibal , Tsukagoshi Takashi , Yamato Yoshihide , van ’t Hoff Merel L. R. , Walsh Catherine , Wilner David J. , Zhang Ke 
Published: November 2021

Abstract
The Molecules with ALMA at Planet-forming Scales (MAPS) Large Program provides a detailed, high-resolution (∼10–20 au) view of molecular line emission in five protoplanetary disks at spatial scales relevant for planet formation. Here we present a systematic analysis of chemical substructures in 18 molecular lines toward the MAPS sources: IM Lup, GM Aur, AS 209, HD 163296, and MWC 480. We identify more than 200 chemical substructures, which are found at nearly all radii where line emission is detected. A wide diversity of radial morphologies—including rings, gaps, and plateaus—is observed both within each disk and across the MAPS sample. This diversity in line emission profiles is also present in the innermost 50 au. Overall, this suggests that planets form in varied chemical environments both across disks and at different radii within the same disk. Interior to 150 au, the majority of chemical substructures across the MAPS disks are spatially coincident with substructures in the millimeter continuum, indicative of physical and chemical links between the disk midplane and warm, elevated molecular emission layers. Some chemical substructures in the inner disk and most chemical substructures exterior to 150 au cannot be directly linked to dust substructure, however, which indicates that there are also other causes of chemical substructures, such as snowlines, gradients in UV photon fluxes, ionization, and radially varying elemental ratios. This implies that chemical substructures could be developed into powerful probes of different disk characteristics, in addition to influencing the environments within which planets assemble. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.
Molecules with ALMA at Planet-forming Scales (MAPS). XIX. Spiral Arms, a Tail, and Diffuse Structures Traced by CO around the GM Aur Disk
Authors: Huang Jane , Bergin Edwin A. , Öberg Karin I. , Andrews Sean M. , Teague Richard , Law Charles J. , Kalas Paul , Aikawa Yuri , Bae Jaehan , Bergner Jennifer B. , Booth Alice S. , Bosman Arthur D. , Calahan Jenny K. , Cataldi Gianni , Cleeves L. Ilsedore , Czekala Ian , Ilee John D. , Le Gal Romane , Guzmán Viviana V. , Long Feng , Loomis Ryan A. , Ménard François , Nomura Hideko , Qi Chunhua , Schwarz Kamber R. , Tsukagoshi Takashi , van ’t Hoff Merel L. R. , Walsh Catherine , Wilner David J. , Yamato Yoshihide , Zhang Ke 
Published: November 2021

Abstract
The concentric gaps and rings commonly observed in protoplanetary disks in millimeter continuum emission have lent the impression that planet formation generally proceeds within orderly, isolated systems. While deep observations of spatially resolved molecular emission have been comparatively limited, they are increasingly suggesting that some disks interact with their surroundings while planet formation is underway. We present an analysis of complex features identified around GM Aur in 12CO J = 2 − 1 images at a spatial resolution of ∼40 au. In addition to a Keplerian disk extending to a radius of ∼550 au, the CO emission traces flocculent spiral arms out to radii of ∼1200 au, a tail extending ∼1800 au southwest of GM Aur, and diffuse structures extending from the north side of the disk up to radii of ∼1900 au. The diffuse structures coincide with a “dust ribbon” previously identified in scattered light. The large-scale asymmetric gas features present a striking contrast with the mostly axisymmetric, multi-ringed millimeter continuum tracing the pebble disk. We hypothesize that GM Aur’s complex gas structures result from late infall of remnant envelope or cloud material onto the disk. The morphological similarities to the SU Aur and AB Aur systems, which are also located in the L1517 cloud, provide additional support to a scenario in which interactions with the environment are playing a role in regulating the distribution and transport of material in all three of these Class II disk systems. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.
Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC3N, CH3CN, and c-C3H2
Authors: Ilee John D. , Walsh Catherine , Booth Alice S. , Aikawa Yuri , Andrews Sean M. , Bae Jaehan , Bergin Edwin A. , Bergner Jennifer B. , Bosman Arthur D. , Cataldi Gianni , Cleeves L. Ilsedore , Czekala Ian , Guzmán Viviana V. , Huang Jane , Law Charles J. , Le Gal Romane , Loomis Ryan A. , Ménard François , Nomura Hideko , Öberg Karin I. , Qi Chunhua , Schwarz Kamber R. , Teague Richard , Tsukagoshi Takashi , Wilner David J. , Yamato Yoshihide , Zhang Ke 
Published: November 2021

Abstract
The precursors to larger, biologically relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. Here, we present 0.″3 observations of HC3N, CH3CN, and c-C3H2 in five protoplanetary disks observed as part of the Molecules with ALMA at Planet-forming Scales (MAPS) Large Program. We robustly detect all molecules in four of the disks (GM Aur, AS 209, HD 163296, and MWC 480) with tentative detections of c-C3H2 and CH3CN in IM Lup. We observe a range of morphologies—central peaks, single or double rings—with no clear correlation in morphology between molecule or disk. Emission is generally compact and on scales comparable with the millimeter dust continuum. We perform both disk-integrated and radially resolved rotational diagram analysis to derive column densities and rotational temperatures. The latter reveals 5–10 times more column density in the inner 50–100 au of the disks when compared with the disk-integrated analysis. We demonstrate that CH3CN originates from lower relative heights in the disks when compared with HC3N, in some cases directly tracing the disk midplane. Finally, we find good agreement between the ratio of small to large nitriles in the outer disks and comets. Our results indicate that the protoplanetary disks studied here are host to significant reservoirs of large organic molecules, and that this planet- and comet-building material can be chemically similar to that in our own solar system. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.
Molecules with ALMA at Planet-forming Scales (MAPS). XII. Inferring the C/O and S/H Ratios in Protoplanetary Disks with Sulfur Molecules
Authors: Le Gal Romane , Öberg Karin I. , Teague Richard , Loomis Ryan A. , Law Charles J. , Walsh Catherine , Bergin Edwin A. , Ménard François , Wilner David J. , Andrews Sean M. , Aikawa Yuri , Booth Alice S. , Cataldi Gianni , Bergner Jennifer B. , Bosman Arthur D. , Cleeves L. Ilse , Czekala Ian , Furuya Kenji , Guzmán Viviana V. , Huang Jane , Ilee John D. , Nomura Hideko , Qi Chunhua , Schwarz Kamber R. , Tsukagoshi Takashi , Yamato Yoshihide , Zhang Ke 
Published: November 2021

Abstract
Sulfur-bearing molecules play an important role in prebiotic chemistry and planet habitability. They are also proposed probes of chemical ages, elemental C/O ratio, and grain chemistry processing. Commonly detected in diverse astrophysical objects, including the solar system, their distribution and chemistry remain, however, largely unknown in planet-forming disks. We present CS (2 − 1) observations at ∼0.″3 resolution performed within the ALMA MAPS Large Program toward the five disks around IM Lup, GM Aur, AS 209, HD 163296, and MWC 480. CS is detected in all five disks, displaying a variety of radial intensity profiles and spatial distributions across the sample, including intriguing apparent azimuthal asymmetries. Transitions of C2S and SO were also serendipitously covered, but only upper limits are found. For MWC 480, we present complementary ALMA observations at ∼ 0.″5 of CS, 13CS, C34S, H2CS, OCS, and SO2. We find a column density ratio N(H2CS)/N(CS) ∼ 2/3, suggesting that a substantial part of the sulfur reservoir in disks is in organic form (i.e., C
x
H
y
S
z
). Using astrochemical disk modeling tuned to MWC 480, we demonstrate that N(CS)/N(SO) is a promising probe for the elemental C/O ratio. The comparison with the observations provides a supersolar C/O. We also find a depleted gas-phase S/H ratio, suggesting either that part of the sulfur reservoir is locked in solid phase or that it remains in an unidentified gas-phase reservoir. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.
Trois modèles de revenu de base
Authors: Vandamme Pierre-Étienne 
Published: November 2021

Parler du revenu de base (revenu universel, allocation universelle) au singulier n’a pas beaucoup de sens. Évaluer une telle proposition dans l’abstraction, sans préciser de quel modèle de revenu de base on parle, encore moins. Il s’agit en effet d’un instrument pouvant être mis au service d’une multitude de causes et aux effets très variés selon le projet politique présidant à son implémentation. Cet article propose pour cette raison de distinguer trois idéaux-types de revenu de base : néolibéral, social-démocrate et de transition écologique et sociale. Ces idéaux-types se distinguent par leurs caractéristiques internes (montant ; financement ; articulation avec les aides sociales existantes) et par les projets politiques qui les guident. La question de la radicalité du revenu de base dépend donc du modèle envisagé. Le modèle « néolibéral » est radical dans la simplification de l’État providence qu’il propose, tandis que le modèle « de transition » l’est dans ses visées de transformation des relations sociales et des dynamiques économiques. Le modèle « social-démocrate », quant à lui, n’entend pas révolutionner la protection sociale, mais constituer une réforme qui, tout en étant plus réaliste à court-terme, est susceptible d’initier une transformation plus graduelle des États sociaux dans le sens d’un renforcement de la protection sociale.
Régulation des plateformes numériques : le moment européen
Authors: Navaro Auburtin Quentin , Weill Mathieu 
Published: November 2021

Le 15 décembre 2020, la Commission européenne a publié deux projets de règlements, le Digital Markets Act (DMA) et le Digital Services Act (DSA). L’objectif : créer le cadre de la régulation des grandes plateformes numériques pour les dix à vingt prochaines années, tant au regard de leurs pratiques économiques devenues hégémoniques qu’au regard du traitement des contenus, traitement pour lequel elles doivent rendre des comptes au plan démocratique. Actes politiques majeurs et longtemps attendus, ces textes sont l’affirmation par l’Europe de ses valeurs et de sa volonté d’établir un modèle ambitieux et précurseur de régulation, à l’instar de ce qui avait été réalisé en matière de protection des données personnelles à travers le RGPD en 2016. Dans cette édification novatrice d’un droit européen de la régulation des plateformes, la France joue depuis plusieurs années un rôle moteur et sa présidence de l’Union européenne en 2022 sera l’occasion de concrétiser ces avancées.
Les principaux enjeux du secteur de la construction
Authors: de Chalendar Pierre-André 
Published: November 2021

Le secteur de la construction a trois enjeux majeurs : le premier s’inscrit dans l’objectif renforcé de réduire les émissions de gaz à effet de serre de 55 % d’ici à 2030 et celui d’atteindre la neutralité carbone d’ici à 2050. Beaucoup de pays, qui représentent 70 % du PIB mondial, se sont engagés à atteindre ce double objectif. Le deuxième enjeu réside dans l’utilisation des ressources primaires qui a triplé ces cinquante dernières années. Le bâtiment est en effet un très gros consommateur de matières premières, et le rythme d’extraction et de production nous précipite inéluctablement vers l’épuisement de ces ressources. Enfin, le troisième enjeu est d’ordre démographique : les prévisions tablent sur une augmentation de la population urbaine de deux milliards d’habitants sur les trente prochaines années. Là réside toute la problématique à laquelle le secteur de la construction se trouve confronté : comment réussir à atteindre la neutralité carbone d’ici à 2050 et à réduire son utilisation des ressources primaires, tout en répondant à la demande en logements consécutive à l’augmentation de la population mondiale ?
Role of Short-Term Estradiol Supplementation in Symptomatic Postmenopausal COVID-19 Females
Authors: Seth Shikha , Sharma Ritu , Mishra Pinky , Solanki Hariom Kumar , Singh Monika , Singh Manisha 
Published: November 2021

Background:
Protective role of estrogen in COVID-19 was speculated once the epidemiological studies reported increased susceptibility of estrogen-deficient population – males and postmenopausal females to severe disease category and involvement of angiotensin-converting enzyme 2 receptors and renin–angiotensin– aldosterone system in pathophysiology.

Materials & Methods:
An open-label randomized controlled trial was planned to assess the efficacy of short-course oral estradiol in preventing the clinical progression to severe disease and reduce case-fatality rate and the hospital stay duration in estrogen-deficient postmenopausal women. The intervention group (n = 40) received 2 mg per day of estradiol valerate per orally for 7 days along with the standard care, while the control group (n = 40) received only the standard care.

Results:
A significant difference was observed in the rate of reverse transcriptase–polymerase chain reaction negativization in the intervention versus control group at day 5 and day 7 of admission (42.5% vs. 15%, P = 0.007; 72.5% versus 50%, P = −0.026). No significant difference was noted in the duration of hospitalization (P = 0.213). A significant decrease was noted in the mean values of inflammatory biomarkers – D-dimer, lactate dehydrogenase, and C-reactive protein on day 5 in the intervention group. Interleukin-6 also showed a declining trend on day 5 in the intervention group, while a rising trend was noted in the control arm. Only one case (2.5%) in the intervention group while seven in the control group (17.5%) progressed to the moderate category; however, the difference was not statistically significant (P = 0.057).

Conclusion
Oral estradiol in postmenopausal females can be a novel and efficient option for managing nonsevere COVID-19 infection.
Pattern of Presentation of Pseudo Exfoliation Deposits on the Lens Capsule in a Tertiary Eye Hospital in Dhaka, Bangladesh
Authors: Ginger-Eke Helen A. , Una Alfred F. I. , Sadiq Abdullahi , Iganga Ogbonnaya N. , Hasan Zafrul , Sarker Bipul K. , Kabir Syed J. , Ogbonnaya Chimdia E. , Ezisi Chinyelu N. 
Published: November 2021

Objective:
To assess the pattern of ocular presentation in patients with pseudoexfoliation syndrome and pseudoexfoliation glaucoma in Ispahani Islamia Eye Institute and Hospital, Dhaka, Bangladesh.

Methods:
This prospective observational study was conducted over 6 months in a glaucoma department of a tertiary eye institute in Bangladesh. All patients diagnosed with pseudoexfoliation glaucoma and pseudoexfoliation syndrome were recruited for the study. Clinical and demographic variables, pattern of presentation of pseudoexfoliation glaucoma and pseudoexfoliation syndrome, location of pseudoexfoliation deposit on the lens surface, and pupillary abnormalities observed with slit lamp examination were analyzed.

Results
A total of 46 eyes of 27 patients with pseudoexfoliation deposit were studied. There were 24 (88.9%) males and the mean age of the patients was 67.0 (±10.8) years. There was peripheral ring of pseudoexfoliation deposit observed on the anterior lens capsule of 12 eyes (n = 12 eyes). However, pseudoexfoliation deposits on the pupillary ruff were the most common pattern of presentation (n = 42 eyes). Poor pupillary dilation was observed in only one eye (n = 1 eye). Open-angle glaucoma was the commonest glaucoma (96.3%) associated with pseudoexfoliation syndrome and the patients had baseline intraocular pressure on the right and left eyes of 22.7 (±12.7) mmHg and 17.5 (±8.0) mmHg, respectively. Bilateral pseudoexfoliation was the most common presentation among patients with pseudoexfoliation glaucoma (n = 20).

Conclusion
Peripheral ring of pseudoexfoliation deposit was the classical deposit on the anterior lens capsule, whereas the central disk was absent in most cases. Poor pupillary dilation was rare.