bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploring the Mass-loss Histories of the Red Supergiants*
Authors: Humphreys Roberta M. , Helmel Greta , Jones Terry J. , Gordon Michael S. 
Published: September 2020

Abstract
We report mid- to far-infrared imaging and photometry from 7 to 37 μm with SOFIA/FORCAST and 2 μm adaptive optics imaging with LBTI/LMIRCam of a large sample of red supergiants (RSGs) in four Galactic clusters: RSGC1, RSGC2 = Stephenson 2, RSGC3, and NGC 7419. The RSGs in these clusters cover their expected range in luminosity and initial mass from ≈9 to more than 25 M
⊙. The population includes examples of very late-type RSGs such as MY Cep, which may be near the end of the RSG stage, high-mass-losing maser sources, yellow hypergiants, and post-RSG candidates. Many of the stars and almost all of the most luminous have spectral energy distributions (SEDs) with extended infrared excess radiation at the longest wavelengths. To best model their SEDs, we use the DUSTY code with a variable radial density distribution function to estimate their mass-loss rates. Our

–luminosity relation for 42 RSGs basically follows the classical de Jager curve, but at luminosities below 105

, we find a significant population of RSGs with

below the de Jager relation. At luminosities above 105
L
⊙, there is a rapid transition to higher mass-loss rates that approximates and overlaps the de Jager curve. We recommend that instead of using a linear relation or single curve, the empirical

–luminosity relation is better represented by a broad band. Interestingly, the transition to much higher

at about 105
L
⊙ corresponds approximately to an initial mass of 18–20 M
⊙, which is close to the upper limit for RSGs becoming Type II supernovae.
Multiple Explanations for the Single Transit of KIC 5951458 Based on Radial Velocity Measurements Extracted with a Novel Matched-template Technique∗
Authors: Dalba Paul A. , Fulton Benjamin , Isaacson Howard , Kane Stephen R. , Howard Andrew W. 
Published: September 2020

Abstract
Planetary systems that show single-transit events are a critical pathway to increasing the yield of long-period exoplanets from transit surveys. From the primary Kepler mission, KIC 5951458 b (Kepler-456b) was thought to be a single-transit giant planet with an orbital period of 1310 days. However, radial velocity (RV) observations of KIC 5951458 from the HIRES instrument on the Keck telescope suggest that the system is far more complicated. To extract precise RVs for this

star, we develop a novel matched-template technique that takes advantage of a broad library of template spectra acquired with HIRES. We validate this technique and measure its noise floor to be 4–8 m s−1 (in addition to internal RV error) for most stars that would be targeted for precision RVs. For KIC 5951458, we detect a long-term RV trend that suggests the existence of a stellar companion with an orbital period greater than a few thousand days. We also detect an additional signal in the RVs that is possibly caused by a planetary or brown dwarf companion with mass in the range of 0.6–82 M
Jup and orbital period below a few thousand days. Curiously, from just the data on hand, it is not possible to determine which object caused the single “transit” event. We demonstrate how a modest set of RVs allows us to update the properties of this unusual system and predict the optimal timing for future observations.
HD 62542: Probing the Bare, Dense Core of a Translucent Interstellar
Cloud*
Authors: Welty Daniel E. , Sonnentrucker Paule , Snow Theodore P. , York Donald G. 
Published: September 2020

Abstract
We discuss the interstellar absorption from many atomic and molecular species
seen in high-resolution Hubble Space Telescope/STIS UV and high signal-to-noise
ratio optical spectra of the moderately reddened B3–5 V star HD 62542. This
remarkable sight line exhibits both very steep far-UV extinction and a high
fraction of hydrogen in molecular form, with strong absorption from CH,
C2, CN, and CO, but weak absorption from CH+ and most
of the commonly observed diffuse interstellar bands. Most of the material
resides in a single narrow velocity component, offering a rare opportunity to
probe the primarily molecular core of a single interstellar cloud with little
associated diffuse atomic gas. Detailed analyses of the spectra indicate that
(1) the molecular fraction in the main cloud is high
(f(H2) ≳ 0.8); (2) the gas is fairly cold
(T
k = 40–43 K; from the rotational excitation of
H2 and C2); (3) the local hydrogen density
n
H ∼ 1500 cm−3 (from C2
excitation, fine-structure excitation of C0, and simple chemical
models); (4) the unusually high excitation temperatures for 12CO and
13CO may be largely due to radiative excitation; (5)
N(C+):N(CO):N(C) ∼ 100:10:1;
(6) the depletions of many elements are more severe than those seen in any other
sight line and the detailed pattern of depletions differs from those derived
from larger samples of Galactic sight lines; and (7) the various neutral/first
ion ratios do not yield consistent estimates for electron density, even when the
effects of grain-assisted recombination and low-temperature dielectronic
recombination are considered.
A New Spin on an Old Black Hole: NuSTAR Spectroscopy of EXO 1846–031
Authors: Draghis Paul A. , Miller Jon M. , Cackett Edward M. , Kammoun Elias S. , Reynolds Mark T. , Tomsick John A. , Zoghbi Abderahmen 
Published: September 2020

Abstract
The black hole candidate EXO 1846-031 underwent an outburst in 2019, after at least 25 yr in quiescence. We observed the system using NuSTAR on 2019 August 3. The 3–79 keV spectrum shows strong relativistic reflection features. Our baseline model gives a nearly maximal black hole spin value of

(1σ statistical errors). This high value nominally excludes the possibility of the central engine harboring a neutron star. Using several models, we test the robustness of our measurement to assumptions about the density of the accretion disk, the nature of the corona, the choice of disk continuum model, and the addition of reflection from the outer regions of the accretion disk. All tested models agree on a very high black hole spin value and a high value for the inclination of the inner accretion disk of

. We discuss the implications of this spin measurement in the population of stellar mass black holes with known spins, including LIGO and Virgo events.
Awakening of Two Gamma-Ray High-redshift, Flat-spectrum Radio Quasars in the Southern Hemisphere
Authors: Li Shang , Sun Lu-Ming , Liao Neng-Hui , Fan Yi-Zhong 
Published: September 2020

Abstract
High-redshift blazars are valuable tools to study the early universe. So far, only a handful of γ-ray blazars have been found at redshifts above 3. Gamma-ray signals are detected in the direction of PMN J2219–2719 (z = 3.63) and PMN J2321–0827 (z = 3.16) by analyzing the 10 yr Fermi-LAT Pass 8 data. PMN J2219–2719 is not distinguished from the background in the global analysis. During the 5 month epoch, the TS value is 47.8 and the flux is more than 10 times that of the 10 yr averaged flux. In addition, the angular distance between the γ-ray position and the radio position of PMN J2219–2719 is only 0.°04. Moreover, the long timescale γ-ray and infrared light curves are very similar, which supports the association between the γ-ray source and PMN J2219–2719. The global analysis of PMN J2321–0827 suggest a new γ-ray source; during the flare phase, the TS value is 61.4 and the γ-ray flux increased significantly. The association probability suggests that PMN J2321–0827 may be the counterpart of the new γ-ray source. In the future, the number of high-redshift γ-ray sources will increase by combining Fermi-LAT and the upcoming Large Synoptic Survey Telescope.
Multi-frequency General Relativistic Radiation-hydrodynamics with M1 Closure
Authors: Anninos Peter , Fragile P. Chris 
Published: September 2020

Abstract
We report on recent upgrades to our general relativistic radiation-magnetohydrodynamics code, Cosmos++, which expands the two-moment,
M

1, radiation treatment from gray to multi-frequency transport, including Doppler and gravitational frequency shifts. The solver accommodates either photon (Bose–Einstein) or neutrino (Fermi–Dirac) statistical distribution functions with absorption, emission, and elastic scattering processes. An implicit scheme is implemented to simultaneously solve the primitive inversion problem together with the radiation–matter coupling source terms, providing stability over a broad range of opacities and optical depths where the interaction terms can be stiff. We discuss our formulations and numerical methods, and validate our methods against a wide variety of test problems spanning optically thin to thick regimes in flat, weakly curved, and strongly curved spacetimes.
Tracking the spread of the northern bark beetle (Ips duplicatus [Sahlb.]) in Europe and first records from Switzerland and Liechtenstein
Authors: Wermelinger Beat , Schneider Mathis Doris , Knížek Miloš , Forster Beat 
Published: September 2020

The northern bark beetle (Ips duplicatus), in Europe originally restricted to northern countries, expanded its distribution range to eastern Europe in the 20th century and is now causing considerable damage in spruce forests. In the past decades its presence has been confirmed in several Central European countries.
By means of pheromone traps and visual inspection of infested logs, in this study we demonstrate that I. duplicatus is also present in the Rhine valley in Switzerland and Liechtenstein. Breeding galleries with beetles and exit holes in an infested spruce log indicate that the trapped beetles had successfully developed in a local stand nearby.
An inquiry addressed to European entomologists was carried out to obtain information and references concerning the year of the first record or mention of I. duplicatus in their respective countries. This information substantiated the expansion of its historical range to the southeast in the middle of the last century and clearly showed recent movement westward, with Switzerland and Germany currently the westernmost countries where this species occurs. This recent range expansion is likely attributed to the transport of infested timber. The economic significance of this expanding bark beetle species is discussed in view of its co-occurrence with the notorious pest species I. typographus.
An International Nursing Student Exchange Program: An Educational Experience that Enhanced Student Cognitive Development
Authors: Frisch Noreen C 
Published: September 2020

ABSTRACT
Increased attention to international nursing has lead to the development of study abroad programs for students. Participants in such programs describe the experiences as positive; however, studies of measured impact have not been reported. Student development theory provides an objective perspective from which to assess the level of cognition of undergraduate students and permits assessment of change in students' thinking maturity over time. This study documents the change of senior students' levels of cognition over one academic semester. Results indicate that those who participated in an international student nurse exchange program demonstrated significantly more growth than those who did not. As nursing moves to a global perspective, the author recommends similar evaluation of all such exchange programs.
Réseaux de crédit et marché textile dans la Cerdagne du Bas Moyen Âge
Authors: Denjean Claude 
Published: September 2020

Durant les XIIIe et XIVe siècles, des communautés juives prospères se développent en Roussillon, Cerdagne et Urgell alors que le marché local de la draperie connaît un essor rapide. L’historiographie traditionnelle lie généralement l’implantation de communautés juives à une demande accrue de numéraire et d’intermédiaires commerciaux sans pouvoir trancher faute de sources assez riches sur la question de l’importance des artisans juifs ; mais toutes les études confirment également que le petit crédit rural demeure la grande affaire des juifs. La reconstitution des réseaux relationnels des juifs de Roussillon et de Cerdagne permet de tenter de répondre à des questions qui méritent encore débat.Nous observons après 1260 l’élaboration des réseaux locaux des nouveaux arrivants, nous voyons les divers associés s’appuyer sur leurs amis et parents languedociens puis catalans. La multiplication des échanges permet la participation de nombreuses familles puis l’émergence d’un groupe réduit capable de prendre une place remarquable dans le commerce local. Cependant, dès le milieu du XIVe siècle, les sociétés juives sont les premières touchées par la crise qui se marque par l’abandon d’activités et surtout par la perte de liens sociaux. Il semble bien que ces difficultés provoquent la réorganisation du semis des implantations juives bien avant les émeutes et les conversions. Cette constatation met en lumière l’extrême variabilité de certaines constructions sociales qui va de pair avec des structures durables.En évaluant la place de communautés particulières dont le rôle dans le courtage a sans doute été survalorisé, nous pouvons surtout chercher à juger l’articulation entre des domaines que nous posons a priori comme distincts : entre le commerce de l’argent et celui de matières premières et de productions textiles, entre le monde rural producteur de laine et de peaux et les marchands urbains, entre les villes de l’axe reliant Perpignan à Urgell, point de passage entre le Languedoc et la Catalogne et donc du commerce international et des centres secondaires.
Minerai de fer, charbon de bois et métal : diversité et complexité des échanges de la sidérurgie ariégeoise dans les Pyrénées (XVIIe-XIXe siècle)
Authors: Cantelaube Jean 
Published: September 2020

Dans le monde des hommes du fer pyrénéens, les temporalités, les échanges et les espaces ne sont pas les mêmes pour tous. Pour se fournir en minerai et charbon de bois, les industriels mobilisent différents réseaux. Ainsi se dessinent plusieurs aires d’approvisionnement très individualisées, conjuguées avec différentes échelles : de la mine de Rancié à un vaste bassin sidérurgique, de la forge à la forêt landaise, du versant français au versant espagnol. La commercialisation des fers bruts en barres tourne le dos aux Pyrénées. Certes, plusieurs courants secondaires existent, certains vers l’Espagne de façon licite ou en contrebande. Mais l’essentiel se fait vers Toulouse qui redistribue le métal sur un grand marché régional. Au XIXe siècle, l’industrie naissante de la cémentation donne au marché une dimension nationale. La complexité de la géographie et des pratiques commerciales a été un gage de pérennité pour la sidérurgie directe ariégeoise.
La vision professionnelle des restaurateurs d’œuvres d’art
Authors: Kreplak Yaël 
Published: September 2020

Qu’est-ce que voir une œuvre d’art professionnellement ? Comment observer et analyser ce regard ? En s’inspirant des travaux de l’anthropologue Charles Goodwin et en prenant appui sur des matériaux ethnographiques, cet article aborde la vision professionnelle des restaurateurs à travers une activité structurante de la profession : la réalisation de constats d’état des œuvres. Produit de l’activité spécifique des restaurateurs, le constat comme document, avec des visuels annotés, est une ressource majeure du travail de la conservation. À travers l’étude de la production, de la mise en forme et de la circulation des constats, j’examine comment s’opère le passage de la situation d’observation au compte-rendu qui en est fait, pour rendre compte de la vision professionnelle des restaurateurs, des modalités de sa mise en forme, de sa transmission et de ses usages. Cet article fournit ainsi une étude de cas des activités pratiques des restaurateurs, ancrée dans une discussion du concept de vision professionnelle forgé par Goodwin.
Être attentif en archéologie
Authors: Torterat Gwendoline 
Published: September 2020

Que signifie être attentif à la fragilité d’un sol archéologique vieux de plusieurs dizaines de milliers d’années ? Pour celles et ceux qui travaillent sur le chantier de fouille préhistorique d’Ormesson (Seine-et-Marne, en France), l’attention est une condition au bien faire, car les conséquences de chaque geste ne se rattrapent pas. Balayer ou gratter, quelle que soit l’action, la transformation du sol s’avère en effet irrévocable, voire fatale dans le cas d’actes manqués, malhabiles et, surtout, effectués avec inattention. C’est à travers les expériences d’une poignée de travailleurs, experts ou non, que cet article propose de restituer la fabrique d’un « savoir voir » en archéologie, une dimension clef pour qui souhaite comprendre les modalités pratiques de la transmission de connaissances au sein de cette profession.
Voir dans la pierre
Authors: Bolay Matthieu , Calvão Filipe 
Published: September 2020

Sur la base d'une étude ethnographique de l’apprentissage de l’évaluation des diamants taillés dans des laboratoires de gemmologie en Belgique et en Inde ainsi que d'entretiens avec des évaluateurs novices et chevronnés (Belgique, États-Unis, Inde, Royaume-Uni, Suisse), cet article propose la notion de réfraction visuelle pour analyser la construction subjective et technique du certificat dans le commerce global du diamant. En analysant l’apprentissage des gestes et les procédures visant à « voir dans la pierre » afin d'ordonner les imperfections d’objets naturels, nous mettons à jour les tensions entre les aspirations d’objectivité et les pratiques visuelles subjectives qui caractérisent le régime de classification de l’industrie diamantaire. Nous soutenons que l’expertise visuelle qu’apprennent les évaluateurs consiste notamment à accepter et valoriser la faillibilité de leurs appréciations sensorielles. Cet apparent paradoxe est selon nous constitutif du système de certification et s’aligne sur la rhétorique de l’exceptionnalité sur laquelle sont construites l’industrie diamantaire et ses marchés.
Visualiser l’endométriose
Authors: Millepied Anne-Charlotte 
Published: September 2020

Cet article porte sur la vision professionnelle des radiologues spécialisé·e·s dans l’endométriose. Le diagnostic y est appréhendé comme un dispositif d’authentification des corps. Il s’agit d’aborder, d’une part, les enjeux liés à la division du travail médical et, d’autre part, ceux liés à l’apprentissage d’habiletés techniques et sensorielles, en cherchant à montrer leur imbrication et leurs implications pour faire advenir au monde une maladie – l’endométriose. La démonstration procède en deux temps : la première partie porte sur le travail de légitimation de l’expertise visuelle des radiologues à travers un travail de frontières avec la chirurgie gynécologique ayant entraîné un déplacement de juridiction au sein du processus diagnostique ; la deuxième partie se centre sur la façon dont les radiologues apprennent à voir l’endométriose et à donner sens aux images produites par le biais de la mobilisation d’un ensemble de prises et repères perceptuels.
l’œil du forestier, instrument et miroir de l’activité professionnelle
Authors: Guidoni-Stoltz Dominique 
Published: September 2020

Dans cet article, nous proposons d’examiner « l’œil du forestier » comme un instrument et un miroir de l’activité cognitive du forestier quand il doit réaliser un diagnostic de parcelle forestière en vue de prendre des décisions d’actions sylvicoles. Comment voir et apprendre à voir dans un environnement vivant que l’ergonomie cognitive qualifie d’environnement complexe et dynamique ? Dans une perspective de didactique professionnelle, nous étudions comment le « savoir voir » des forestiers s’exerce en situation, s’enseigne et se construit en formation. Nous analysons les compétences visuelles des forestiers mobilisées dans l’activité professionnelle en situation de travail et en formation et dégageons les principaux concepts organisateurs qui structurent leur représentation de la forêt. Nous modélisons à la suite une structure conceptuelle de la situation de diagnostic d’une parcelle forestière prenant en compte différentes variables et indicateurs pour raisonner et articuler peuplement et station, production et écologie. Ces résultats peuvent constituer une ressource potentielle au développement d’une intelligence professionnelle du « savoir voir » forestier.
Transitioning from Face-to-Face to Remote Learning: Students’ Attitudes and Perceptions of using Zoom during COVID-19 Pandemic
Authors: Serhan Derar 
Published: September 2020

Due to the COVID-19 pandemic and during the middle of the spring 2020 semester, many universities were forced to move from face-to-face (FTF) in-classroom to remote instruction. Many institutions used Zoom as their delivery platform. The purpose of this study was to investigate students’ attitudes towards the use of Zoom in remote learning, and their perceptions of its effects on their learning and engagement in comparison to FTF learning. Thirty-one university students participated in this study. Data were collected using a 5-point Likert-type survey. The results indicated that students had a negative attitude toward the use of Zoom and perceived it as having a negative effect on their learning experience and their motivation to learn. Students listed flexibility as a main advantage to using Zoom for learning.
Make Internationalism Great Again: The AIB in an Age of Populist Nationalism
Authors: Kobrin Stephen J. 
Published: September 2020

Is globalization – an open an integrated international economy – an aberration or the norm? The first wave ended with WWI and then the Great Depression and the second is faltering with the Great Recession and the rise of populist nationalism. This essay asks whether it is possible to find a balance between global integration and national independence that provides the benefits of the former while allowing a satisfactory degree of national control, and whether a viable international system based on the rule of law can be constructed given the great diversity of national political and economic systems in the world today.
The Importance of Institutional Knowledge for Expats Working in Latin America
Authors: Friel Daniel 
Published: September 2020

This article contends that the training of expats should include explanations of how critical institutions shape the ability of multinational corporations to transfer best practices to their foreign subsidiaries. It illustrates the importance of this topic by examining why an Argentine company failed in Brazil because it did not understand how critical differences between labor laws and supplier relations between this country and Argentina. By contrast, the French company was successful in Brazil and Argentina because it understood how it had to adapt its lean production program to the particularities of industrial and employee relations in these countries.
Introduction to the 2016 Peter J. Buckley and Mark Casson AIB Dissertation Award.
Authors: Phene Anupama 
Published: September 2020

This article discusses the 2016 Peter J. Buckley and Mark Casson AIB dissertation award. It documents the nature and geographic dispersion of the submissions and the selection process utilized to identify finalists and the winner of the award. The finalist dissertations reflect a broad set of topics related to corporate social responsibility, language strategy, connectivity of peripheral economies and exploration of the role of headquarters in the multinational firm. Posing the right questions, anchoring these questions in theoretical foundations while pursuing cutting edge empirical techniques allows doctoral students to craft a dissertation that is a strong aspirant for the award.