bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyclic Period Oscillation of the Eclipsing Dwarf Nova DV UMa
Authors: Han Z.-T , Qian S.-B , Irina Voloshina , Zhu L.-Y 
Published: May 2017

Abstract
DV UMa is an eclipsing dwarf nova with an orbital period of ∼2.06 hr, which lies just at the bottom edge of the period gap. To detect its orbital period changes, we present 12 new mid-eclipse times by using our CCD photometric data and archival data. The latest version of the O–C diagram, combined with the published mid-eclipse times in quiescence, and spanning ∼30 years, was obtained and analyzed. The best fit to those available eclipse timings shows that the orbital period of DV UMa is undergoing a cyclic oscillation with a period of

years and an amplitude of

s. The periodic variation most likely arises from the light-travel-time effect via the presence of a circumbinary object, because the required energy to drive the Applegate mechanism is too high in this system. The mass of the unseen companion was derived as

. If the third body is in the orbital plane (i.e.,

) of the eclipsing pair, this would indicate it is a brown dwarf. This hypothetical brown dwarf is orbiting its host star at a separation of ∼8.6 au in an eccentric orbit (e = 0.44).
Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing
Authors: Edelson R. , Gelbord J. , Cackett E. , Connolly S. , Done C. , Fausnaugh M. , Gardner E. , Gehrels N. , Goad M. , Horne K. , McHardy I. , Peterson B. M. , Vaughan S. , Vestergaard M. , Breeveld A. , Barth A. J. , Bentz M. , Bottorff M. , Brandt W. N. , Crawford S. M. , Bontà E. Dalla , Emmanoulopoulos D. , Evans P. , Jaimes R. Figuera , Filippenko A. V. , Ferland G. , Grupe D. , Joner M. , Kennea J. , Korista K. T. , Krimm H. A. , Kriss G. , Leonard D. C. , Mathur S. , Netzer H. , Nousek J. , Page K. , Romero-Colmenero E. , Siegel M. , Starkey D. A. , Treu T. , Vogler H. A. , Winkler H. , Zheng W. 
Published: May 2017

Abstract

Swift monitoring of NGC 4151 with an ∼6 hr sampling over a total of 69 days in early 2016 is used to construct light curves covering five bands in the X-rays (0.3–50 keV) and six in the ultraviolet (UV)/optical (1900–5500 Å). The three hardest X-ray bands (>2.5 keV) are all strongly correlated with no measurable interband lag, while the two softer bands show lower variability and weaker correlations. The UV/optical bands are significantly correlated with the X-rays, lagging ∼3–4 days behind the hard X-rays. The variability within the UV/optical bands is also strongly correlated, with the UV appearing to lead the optical by ∼0.5–1 days. This combination of ≳3 day lags between the X-rays and UV and ≲1 day lags within the UV/optical appears to rule out the “lamp-post” reprocessing model in which a hot, X-ray emitting corona directly illuminates the accretion disk, which then reprocesses the energy in the UV/optical. Instead, these results appear consistent with the Gardner & Done picture in which two separate reprocessings occur: first, emission from the corona illuminates an extreme-UV-emitting toroidal component that shields the disk from the corona; this then heats the extreme-UV component, which illuminates the disk and drives its variability.
Magnetic Helicity Estimations in Models and Observations of the Solar Magnetic Field. III. Twist Number Method
Authors: Guo Y. , Pariat E. , Valori G. , Anfinogentov S. , Chen F. , Georgoulis M. K. , Liu Y. , Moraitis K. , Thalmann J. K. , Yang S. 
Published: May 2017

Abstract
We study the writhe, twist, and magnetic helicity of different magnetic flux ropes, based on models of the solar coronal magnetic field structure. These include an analytical force-free Titov–Démoulin equilibrium solution, non-force-free magnetohydrodynamic simulations, and nonlinear force-free magnetic field models. The geometrical boundary of the magnetic flux rope is determined by the quasi-separatrix layer and the bottom surface, and the axis curve of the flux rope is determined by its overall orientation. The twist is computed by the Berger–Prior formula, which is suitable for arbitrary geometry and both force-free and non-force-free models. The magnetic helicity is estimated by the twist multiplied by the square of the axial magnetic flux. We compare the obtained values with those derived by a finite volume helicity estimation method. We find that the magnetic helicity obtained with the twist method agrees with the helicity carried by the purely current-carrying part of the field within uncertainties for most test cases. It is also found that the current-carrying part of the model field is relatively significant at the very location of the magnetic flux rope. This qualitatively explains the agreement between the magnetic helicity computed by the twist method and the helicity contributed purely by the current-carrying magnetic field.
X-Ray-induced Deuterium Enrichment of N-rich Organics in Protoplanetary Disks: An Experimental Investigation Using Synchrotron Light
Authors: Gavilan Lisseth , Remusat Laurent , Roskosz Mathieu , Popescu Horia , Jaouen Nicolas , Sandt Christophe , Jäger Cornelia , Henning Thomas , Simionovici Alexandre , Lemaire Jean Louis , Mangin Denis , Carrasco Nathalie 
Published: May 2017

Abstract
The deuterium enrichment of organics in the interstellar medium, protoplanetary disks, and meteorites has been proposed to be the result of ionizing radiation. The goal of this study is to simulate and quantify the effects of soft X-rays (0.1–2 keV), an important component of stellar radiation fields illuminating protoplanetary disks, on the refractory organics present in the disks. We prepared tholins, nitrogen-rich organic analogs to solids found in several astrophysical environments, e.g., Titan’s atmosphere, cometary surfaces, and protoplanetary disks, via plasma deposition. Controlled irradiation experiments with soft X-rays at 0.5 and 1.3 keV were performed at the SEXTANTS beamline of the SOLEIL synchrotron, and were immediately followed by ex-situ infrared, Raman, and isotopic diagnostics. Infrared spectroscopy revealed the preferential loss of singly bonded groups (N–H, C–H, and R–N≡C) and the formation of sp3 carbon defects with signatures at ∼1250–1300 cm−1. Raman analysis revealed that, while the length of polyaromatic units is only slightly modified, the introduction of defects leads to structural amorphization. Finally, tholins were measured via secondary ion mass spectrometry to quantify the D, H, and C elemental abundances in the irradiated versus non-irradiated areas. Isotopic analysis revealed that significant D-enrichment is induced by X-ray irradiation. Our results are compared to previous experimental studies involving the thermal degradation and electron irradiation of organics. The penetration depth of soft X-rays in μm-sized tholins leads to volume rather than surface modifications: lower-energy X-rays (0.5 keV) induce a larger D-enrichment than 1.3 keV X-rays, reaching a plateau for doses larger than 5 × 1027 eV cm−3. Synchrotron fluences fall within the expected soft X-ray fluences in protoplanetary disks, and thus provide evidence of a new non-thermal pathway to deuterium fractionation of organic matter.
Magnetohydrodynamic Modeling of Solar Coronal Dynamics with an Initial Non-force-free Magnetic Field
Authors: Prasad A. , Bhattacharyya R. , Kumar Sanjay 
Published: May 2017

Abstract
The magnetic fields in the solar corona are generally neither force-free nor axisymmetric and have complex dynamics that are difficult to characterize. Here we simulate the topological evolution of solar coronal magnetic field lines (MFLs) using a magnetohydrodynamic model. The simulation is initialized with a non-axisymmetric non-force-free magnetic field that best correlates with the observed vector magnetograms of solar active regions (ARs). To focus on these ideas, simulations are performed for the flaring AR 11283 noted for its complexity and well-documented dynamics. The simulated dynamics develops as the initial Lorentz force pushes the plasma and facilitates successive magnetic reconnections at the two X-type null lines present in the initial field. Importantly, the simulation allows for the spontaneous development of mass flow, unique among contemporary works, that preferentially reconnects field lines at one of the X-type null lines. Consequently, a flux rope consisting of low-lying twisted MFLs, which approximately traces the major polarity inversion line, undergoes an asymmetric monotonic rise. The rise is attributed to a reduction in the magnetic tension force at the region overlying the rope, resulting from the reconnection. A monotonic rise of the rope is in conformity with the standard scenario of flares. Importantly, the simulated dynamics leads to bifurcations of the flux rope, which, being akin to the observed filament bifurcation in AR 11283, establishes the appropriateness of the initial field in describing ARs.
Statistical Analysis of Supernova Remnants in the Large Magellanic Cloud
Authors: Bozzetto Luke M. , Filipović Miroslav D. , Vukotić Branislav , Pavlović Marko Z. , Urošević Dejan , Kavanagh Patrick J. , Arbutina Bojan , Maggi Pierre , Sasaki Manami , Haberl Frank , Crawford Evan J. , Roper Quentin , Grieve Kevin , Points S. D. 
Published: May 2017

Abstract
We construct the most complete sample of supernova remnants (SNRs) in any galaxy—the Large Magellanic Cloud (LMC) SNR sample. We study their various properties such as spectral index (α), size, and surface brightness. We suggest an association between the spatial distribution and environment density of LMC SNRs, and their tendency to be located around supergiant shells. We find evidence that the 16 known type Ia LMC SNRs are expanding in a lower density environment compared to the Core-Collapse (CC) type. The mean diameter of our entire population (74) is 41 pc, which is comparable to nearby galaxies. We did not find any correlation between the type of SN explosion, ovality, or age. The

relationship with slope a = 0.96 implies that the randomized diameters are readily mimicking such an exponent. The rate of SNe occurring in the LMC is estimated to be ∼1 per 200 yr. The mean α of the entire LMC SNR population is −0.52, which is typical of most SNRs. However, our estimates show a clear flattening of the synchrotron α as the remnants age. As predicted, the CC SNRs in our sample are significantly brighter radio emitters than type Ia remnants. We also estimate the

relation for the LMC to have a slope ∼3.8, which is comparable with other nearby galaxies. We also find the residency time of electrons in the galaxy (4.0–14.3 Myr), implying that SNRs should be the dominant mechanism for the production and acceleration of CRs.
Diplôme et carrière : un lien indéfectible ? Le cas d’une grande entreprise de télécommunication
Authors: Zannad Hédia , Galindo Géraldine 
Published: May 2017

Si la centralité du diplôme dans le processus de recrutement et d’évolution du début de carrière est une affaire de bon sens, elle est plus difficile à accepter – voire à être perçue comme un motif de discrimination – lorsqu’elle perdure tout au long de la carrière, et notamment quand il s’agit d’accéder aux postes de direction d’une organisation, puisqu’on devrait plutôt s’attendre à ce que seules les compétences et performances soient prises en compte à ce stade. S’il est particulièrement difficile de mesurer l’impact socio-économique d’un système dans lequel les diplômés des grandes écoles ont un accès prioritaire aux fonctions dirigeantes des entreprises, il est en revanche plus aisé d’analyser, à un niveau individuel, le rôle joué par le diplôme dans la trajectoire des salariés. C’est cette question qui est soulevée dans le cadre d’une entreprise qui accorde de l’importance aux diplômes de prestige : le groupe Orange. Cette étude de cas montre que l’attitude des salariés face à l’accès privilégié des diplômés de grandes écoles aux postes de direction, n’est pas nécessairement négative et que les salariés qui « réussissent » malgré un diplôme de rang 2 ont mis en œuvre des mécanismes de compensations spécifiques telles que des compétences spécialisées, une forte mobilité géographique ou un travail en mode projet.
Troubles dans le féminisme
Authors: Guionnet Christine 
Published: May 2017

Les sondages d’opinion se succèdent régulièrement pour insister sur l’image négative, aujourd’hui attachée à un certain type de féminisme. Pourtant, ces mêmes sondages montrent que certaines valeurs portées par le féminisme sont toujours considérées comme importantes par une majorité de sondés. Ce trouble dans le féminisme est-il visible sur la toile ? Pour le savoir, nous avons choisi d’analyser des discussions entre internautes sur des sites non militants, notre objectif consistant à analyser les réappropriations ordinaires du féminisme et de l’antiféminisme par des citoyens non engagés. Nous montrons combien les forums observés contribuent à mettre en exergue une « zone grise » de réappropriations citoyennes brouillant les frontières entre féminisme et antiféminisme. Internet accentue, à cet égard, le trouble dans le féminisme.
Négocier l’action publique dans un État sous régime d’aide : une analyse comparée des politiques de l’enseignement supérieur et du foncier en Tanzanie
Authors: Provini Olivier , Schlimmer Sina 
Published: May 2017

Depuis le milieu des années 1970, la Tanzanie fait l’objet d’une attention toute particulière de la communauté internationale en captant la plus grande part d’aide au développement de l’Afrique subsaharienne. Cette donnée empirique a suscité l’intérêt de nombreux chercheurs et experts internationaux qui construisent la Tanzanie comme un « donor darling ». Pourtant, ces études omettent les impacts de cette économie politique singulière sur le processus de l’action publique. L’objectif de notre article est, à travers une étude sectorialisée et comparative originale, d’appréhender les conséquences de ces réseaux internationaux d’acteurs sur la fabrique des politiques publiques. En s’appuyant sur les processus de politiques publiques dans les secteurs de l’enseignement supérieur et du foncier, nous postulons que cette articulation doit s’effectuer par une approche socio-historique de l’État tanzanien. En partant des résultats de la littérature qui conclut généralement un contournement de l’État (privatisation des universités, accaparement des terres), nous démontrons que l’action publique, négociée et historicisée, participe à la formation de l’État.
Les Kosmiker
Authors: Sirost Olivier 
Published: May 2017

Illuministes et théosophes posent au XVIII e siècle les bases nouvelles d’une cosmologie conjuguant l’énergétique héraclitéenne et l’émersion parménidienne. Cette entreprise est notamment guidée par le Sensorium Dei de Franz von Baader, un nouvel âge de la nature qui est réapproprié par les Naturphilosophes au Stift de Tübingen, en particulier Hölderlin, Schelling et Hegel, ouvrant sur une astrologie intérieure, une météosensibilité et les démons du paganisme. Ces trois thématiques vont alimenter la bohème européenne, des Mardis de Mallarmé au Cercle cosmique de Schwabing. Les cultes dionysiens qui y sont célébrés composent alors le terreau des utopies communautaires qui se déploient de Monte Verità à la Beat Generation.
Médée Fukushima
Authors: Moreau Yoann 
Published: May 2017

La part radioactive de Fukushima n’est pas spectaculaire mais spectrale. Nous faisons l’hypothèse que son impact symbolique – la peur et les angoisses engendrées par la radioactivité – ont plus d’impact que sa part mesurable et rationnelle. Peut-on l’appréhender à partir d’une dramaturgie et d’une épistémologie classiques ? Face aux catastrophes, quelle est la pertinence des mythes ?
Un enfant ou un emploi ? Dilemme des Allemandes de l’Est et de l’Ouest
Authors: Kreyenfeld Michaela , Konietzka Dirk 
Published: May 2017

En Allemagne de l’Est, avant la réunification, moins de 10 % des femmes n’avaient pas d’enfants, tandis qu’en Allemagne de l’Ouest leur nombre avait augmenté régulièrement pour atteindre plus de 20 %. Cet article s’intéresse à cette évolution divergente en s’appuyant sur les données d’un micro-recensement. Il étudie les politiques sociales qui ont influencé l’emploi des femmes et les modèles familiaux avant la réunification. Il aborde aussi d’autres tendances et réformes plus récentes, et notamment le développement de l’accueil des jeunes enfants et la réforme de l’allocation de congé parental en 2007. Si les modèles familiaux et les régimes d’emploi ont eu tendance à s’aligner dans l’est et l’ouest de l’Allemagne réunifiée, des différences de comportement subsistent. Aujourd’hui encore, il est plus courant pour une femme de ne pas avoir d’enfants dans l’ouest que dans l’est du pays. En outre, les femmes est-allemandes travaillent en règle générale à temps plein, tandis que le taux de mères ouest-allemandes qui travaillent à temps plein n’augmente que progressivement.
Virtual Gaming Simulation in Nursing Education: A Focus Group Study
Authors: Verkuyl Margaret , Hughes Michelle , Tsui Joyce , Betts Lorraine , St-Amant Oona , Lapum Jennifer L. 
Published: May 2017

Background:
The use of serious gaming in a virtual world is a novel pedagogical approach in nursing education. A virtual gaming simulation was implemented in a health assessment class that focused on mental health and interpersonal violence. The study's purpose was to explore students' experiences of the virtual gaming simulation.

Method:
Three focus groups were conducted with a convenience sample of 20 first-year nursing students after they completed the virtual gaming simulation.

Results:
Analysis yielded five themes: (a) Experiential Learning, (b) The Learning Process, (c) Personal Versus Professional, (d) Self-Efficacy, and (e) Knowledge.

Conclusion:

Virtual gaming simulation can provide experiential learning opportunities that promote engagement and allow learners to acquire and apply new knowledge while practicing skills in a safe and realistic environment. [
J Nurs Educ.
2017;56(5):274–280.]
Harlequin-Inspired Story-Based Learning: An Educational Innovation for Pediatric Nursing Communication
Authors: Shaw Alison , Lind Candace , Ewashen Carol 
Published: May 2017

Background:
Effective communication with patients and families is essential for quality care in the pediatric environment. Despite this, the current structure and content of undergraduate nursing education often contributes to novice RNs feeling unprepared to manage complex pediatric communication situations.

Method:
By merging the characteristics of the Harlequin persona with the structure of story-based learning, undergraduate students can be introduced to increasingly advanced pediatric communication scenarios in the classroom. Although story-based learning encourages students to identify and address the contextual and emotional elements of a story, the Harlequin encourages educators to challenge assumptions and upset the status quo.

Results:
Nursing students can develop advanced communication abilities and learn to identify and cope with the emotions and complexities inherent in pediatric practice and communication.

Conclusion:

Harlequin-inspired story-based learning can enable nurse educators to create interesting, realistic, and challenging pediatric nursing stories designed to push students outside their comfort zones and enhance their advanced pediatric communication abilities. [
J Nurs Educ.
2017;56(5):300–303.]
Multiple Retroperitoneal Paragangliomas: An Uncommon Entity
Authors: Singh Ashu , Shikha Deep , Agarwal Shipra , Jain Shyam Lata , Hadke NS 
Published: May 2017

ABSTRACTIntroductionParagangliomas are neuroendocrine tumors and occur commonly in head and neck region and less frequently in the retroperitoneum. Multifocal paragangliomas are even rarer and highly suggestive of familial disease. To the best of our search, there are only two case reports of multiple retroperitoneal paragangliomas with no known familial association. This is the third report of this kind in the English literature.Case reportA young adult with no significant past or family history presented with abdominal pain and anorexia. Abdominal examination revealed a soft nontender mass in the right hypochondrium. Contrast-enhanced computed tomography showed multiple retroperitoneal mass lesions. A clinicoradiological diagnosis of multicentric Castleman's disease/Lymphoma was made. Guided fine needle aspiration of the mass was suggestive of a neuroendocrine neoplasm. Tru-cut biopsy showed features of paraganglioma. Following this, the masses were excised and the diagnosis of paraganglioma was confirmed.ConclusionMulticentric retroperitoneal paragangliomas without any familial association are very rare with only two case reports in the English literature. Lack of symptoms makes the diagnosis difficult and also makes our case unique. Biopsy from paragangliomas and surgical intervention are known to cause life-threatening complications, such as profuse bleeding and abrupt changes in blood pressure. Hence, paragangliomas should be considered as a possibility, even if a remote one, in case of multicentric retroperitoneal tumors. This case also highlights the importance of cytology in the early diagnosis of retroperitoneal masses.How to cite this articleSingh A, Shikha D, Agarwal S, Khurana N, Jain SL, Hadke NS. Multiple Retroperitoneal Paragangliomas: An Uncommon Entity. World J Endoc Surg 2017;9(1):20-23.
Tertiary Hyperparathyroidism Secondary to X-linked Hypophosphatemic Rickets
Authors: Cebrian Jose Maria Fernandez , Ruiz Enrique Colás , Vega Laura , Linacero Santiago , Celi Edgardo , Quintáns Antonio 
Published: May 2017

ABSTRACT
Tertiary hyperparathyroidism is a rare complication of X-linked hypophosphatemic rickets. The surgical treatment is already unclear.

How to cite this article
Ruiz EC, Cebrián JMF, Vega L, Linacero S, Celi E, Quintáns A. Tertiary Hyperparathyroidism Secondary to X-linked Hypophosphatemic Rickets. World J Endoc Surg 2017;9(1):24-26.
Beahrs’ Triangle: The Surgical Anatomy
Authors: Jain Vikas 
Published: May 2017

ABSTRACT
Thyroidectomy is a commonly performing surgery worldwide with known complications of recurrent laryngeal nerve injury (RLN) and vocal cord paralysis. To avoid RLN palsy, various methods of RLN identification have been defined, one of which is called as defining Beahrs’ triangle.

How to cite this article
Jain V. Beahrs’ Triangle: The Surgical Anatomy. World J Endoc Surg 2017;9(1):35.
Ultrasound Imaging of Early Extraembryonic Structures
Authors: Nagy Sándor , Papp Zoltán 
Published: May 2017

ABSTRACT
Transvaginal sonography is the most useful diagnostic method to visualize the early pregnancy, to determine whether it is intrauterine or extrauterine (ectopic), viable or not. Detailed examination of extraembryonic structures allows us to differentiate the types of early pregnancy failures and highlights the backgrounds of vaginal bleeding, as the most frequent symptom of the first trimester of gestation. The reliable ultrasonographic sign of an intrauterine pregnancy is visualization of double decidual ring, which represents the trophoblast's layer. The abnormality in the sonographic appearance of a gestational sac, a yolk sac, and a chorionic plate can predict subsequent embryonic damage and death.
How to cite this article
Nagy S, Papp Z. Ultrasound Imaging of Early Extraembryonic Structures. Donald School J Ultrasound Obstet Gynecol 2017;11(1):11-19.