bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tidal Disruptions of Main-sequence Stars. II. Simulation Methodology and Stellar Mass Dependence of the Character of Full Tidal Disruptions
Authors: Ryu Taeho , Krolik Julian , Piran Tsvi , Noble Scott C. 
Published: November 2020

Abstract
This is the second in a series of papers presenting the results of fully general relativistic simulations of stellar tidal disruptions in which the stars’ initial states are realistic main-sequence models. In the first paper, we gave an overview of this program and discussed the principal observational implications of our work. Here we describe our calculational method, which includes a new method for calculating fully relativistic stellar self-gravity, and provide details about the outcomes of full disruptions, focusing on the stellar mass dependence of the outcomes for a black hole of mass 106
M
⊙. We consider eight different stellar masses, from 0.15 M
⊙ to 10 M
⊙. We find that, relative to the traditional order-of-magnitude estimate r
t, the physical tidal radius of low-mass stars (M
⋆ ≲ 0.7 M
⊙) is larger by tens of percent, while for high-mass stars (M
⋆ ≳ 1 M
⊙) it is smaller by a factor of 2–2.5. The traditional estimate of the range of energies found in the debris is ≈1.4× too large for low-mass stars, but is a factor of ∼2 too small for high-mass stars; in addition, the energy distribution for high-mass stars has significant wings. For all stars undergoing tidal encounters, we find that mass loss continues for many stellar vibration times because the black hole's tidal gravity competes with the instantaneous stellar gravity at the star's surface until the star has reached a distance from the black hole ∼O(10)r
t.
Tidal Disruptions of Main-sequence Stars. I. Observable Quantities and Their Dependence on Stellar and Black Hole Mass
Authors: Ryu Taeho , Krolik Julian , Piran Tsvi , Noble Scott C. 
Published: November 2020

Abstract
This paper introduces a series of papers presenting a quantitative theory for the tidal disruption of main-sequence stars by supermassive black holes. Using fully general relativistic hydrodynamics simulations and MESA-model initial conditions, we explore the pericenter-dependence of tidal disruption properties for eight stellar masses (

) and six black hole masses (

). We present here the results most relevant to observations. The effects of internal stellar structure and relativity decouple for both the disruption cross section and the characteristic energy width of the debris. Moreover, the full disruption cross section is almost independent of M
⋆ for M
⋆/M
⊙ ≲ 3. Independent of M
⋆, relativistic effects increase the critical pericenter distance for full disruption events by up to a factor of ∼3 relative to the Newtonian prediction. The probability of a direct capture is also independent of M
⋆; at M
BH/M
⊙ ≃ 5 × 106 this probability is equal to the probability of a complete disruption. The breadth of the debris energy distribution ΔE can differ from the standard estimate by factors of 0.35 − 2, depending on M
⋆ and M
BH, implying a corresponding change (∝(ΔE)−3/2) in the characteristic mass-return timescale. We provide analytic forms, suitable for use in both event rate estimates and parameter inference, to describe all these trends. For partial disruptions, we find a nearly universal relation between the star’s angular momentum and the fraction of M
⋆ remaining. Within the “empty loss-cone” regime, partial disruptions must precede full disruptions. These partial disruptions can drastically affect the rate and appearance of subsequent total disruptions.
Constraining Hadron-quark Phase Transition Parameters within the Quark-mean-field Model Using Multimessenger Observations of Neutron Stars
Authors: Miao Zhiqiang , Li Ang , Zhu Zhenyu , Han Sophia 
Published: November 2020

Abstract
We extend the quark mean-field (QMF) model for nuclear matter and study the possible presence of quark matter inside the cores of neutron stars. A sharp first-order hadron-quark phase transition is implemented combining the QMF for the hadronic phase with “constant-speed-of-sound” parameterization for the high-density quark phase. The interplay of the nuclear symmetry energy slope parameter, L, and the dimensionless phase transition parameters (the transition density n
trans/n
0, the transition strength Δε/ε
trans, and the sound speed squared in quark matter

) are then systematically explored for the hybrid star properties, especially the maximum mass M
max and the radius and the tidal deformability of a typical 1.4 M
⊙ star. We show the strong correlation between the symmetry energy slope L and the typical stellar radius R
1.4, similar to that previously found for neutron stars without a phase transition. With the inclusion of phase transition, we obtain robust limits on the maximum mass (M
max < 3.6 M
⊙) and the radius of 1.4 M
⊙ stars (R
1.4 ≳ 9.6 km), and we find that a phase transition that is too weak (Δε/ε
trans ≲ 0.2) taking place at low densities ≲1.3–1.5 n
0 is strongly disfavored. We also demonstrate that future measurements of the radius and tidal deformability of ∼1.4 M
⊙ stars, as well as the mass measurement of very massive pulsars, can help reveal the presence and amount of quark matter in compact objects.
Breaking the Dark Degeneracy with the Drifting Coefficient of the Field Cluster Mass Function
Authors: Ryu Suho , Lee Jounghun , Baldi Marco 
Published: November 2020

Abstract
We present a numerical analysis supporting the evidence that the redshift evolution of the drifting coefficient of the field cluster mass function is capable of breaking several cosmic degeneracies. This evidence is based on the data from the CoDECS and DUSTGRAIN-pathfinder simulations performed separately for various nonstandard cosmologies including coupled dark energy, f(R) gravity, and combinations of f(R) gravity with massive neutrinos as well as for the standard Λ cold dark matter (ΛCDM) cosmology. We first numerically determine the field cluster mass functions at various redshifts in the range of 0 ≤ z ≤ 1 for each cosmology. Then, we compare the analytic formula developed in previous works with the numerically obtained field cluster mass functions by adjusting its drifting coefficient, β, at each redshift. It is found that the analytic formula with the best-fit coefficient provides a good match to the numerical results at all redshifts for all of the cosmologies. The empirically determined redshift evolution of the drifting coefficient, β(z), turns out to significantly differ among different cosmologies. It is also shown that even without using any prior information on the background cosmology the drifting coefficient, β(z), can discriminate with high statistical significance the degenerate nonstandard cosmologies not only from the ΛCDM but also from one another. It is concluded that the evolution of the departure from the Einstein–de Sitter state and spherically symmetric collapse processes quantified by β(z) is a powerful probe of gravity and dark sector physics.
Statistical Signatures of Nanoflare Activity. II. A Nanoflare Explanation for Periodic Brightenings in Flare Stars Observed by NGTS
Authors: Dillon C. J. , Jess D. B. , Mathioudakis M. , Watson C. A. , Jackman J. A. G. , Wheatley P. J. , Goad M. R. , Casewell S. L. , Anderson D. R. , Burleigh M. R. , Raynard L. , West R. G. 
Published: November 2020

Abstract
Several studies have documented periodic and quasi-periodic signals from the time series of dMe flare stars and other stellar sources. Such periodic signals, observed within quiescent phases (i.e., devoid of larger-scale microflare or flare activity), range in a period from 1 to 1000 s and hence have been tentatively linked to ubiquitous p-mode oscillations generated in the convective layers of the star. As such, most interpretations for the observed periodicities have been framed in terms of magnetohydrodynamic wave behavior. However, we propose that a series of continuous nanoflares, based upon a power-law distribution, can provide a similar periodic signal in the associated time series. Adapting previous statistical analyses of solar nanoflare signals, we find the first statistical evidence for stellar nanoflare signals embedded within the noise envelope of M-type stellar lightcurves. Employing data collected by the Next Generation Transit Survey (NGTS), we find evidence for stellar nanoflare activity demonstrating a flaring power-law index of 3.25 ± 0.20, alongside a decay timescale of 200 ± 100 s. We also find that synthetic time series, consistent with the observations of dMe flare star lightcurves, are capable of producing quasi-periodic signals in the same frequency range as p-mode signals, despite being purely composed of impulsive signatures. Phenomena traditionally considered a consequence of wave behavior may be described by a number of high-frequency but discrete nanoflare energy events. This new physical interpretation presents a novel diagnostic capability, by linking observed periodic signals to given nanoflare model conditions.
Rotational Spectra of Vibrationally Excited AlO and TiO in Oxygen-rich Stars
Authors: Danilovich T. , Gottlieb C. A. , Decin L. , Richards A. M. S. , Lee K. L. K. , Kamiński T. , Patel N. A. , Young K. H. , Menten K. M. 
Published: November 2020

Abstract
Rotational transitions in vibrationally excited AlO and TiO—two possible precursors of dust—were observed in the 300 GHz range (1 mm wavelength) toward the oxygen-rich asymptotic giant branch (AGB) stars R Dor and IK Tau with ALMA, and vibrationally excited AlO was observed toward the red supergiant VY CMa with the SMA. The J = 11 → 10 transition of TiO in the v = 1 and 2 levels and the N = 9 → 8 transition in the v = 2 level of AlO were identified toward R Dor, the J = 11 → 10 line of TiO was identified in the v = 1 level toward IK Tau, and two transitions in the v = 1 and 2 levels of AlO were identified toward VY CMa. The newly derived high vibrational temperature of TiO and AlO in R Dor of 1800 ± 200 K and prior measurements of the angular extent confirm that the majority of the emission is from a region within ≲2R
⋆ of the central star. A full radiative transfer analysis of AlO in R Dor yielded a fractional abundance of ∼3% of the solar abundance of Al. From a similar analysis of TiO a fractional abundance of ∼78% of the solar abundance of Ti was found. The observations provide indirect evidence that TiO is present in a rotating disk close to the star. Further observations in the ground and excited vibrational levels are needed to determine whether AlO, TiO, and TiO2 are seeds of the Al2O3 dust in R Dor, and perhaps in the gravitationally bound dust shells in other AGB stars with low mass-loss rates.
Detection of Opposite Magnetic Polarity in a Light Bridge: Its Emergence and Cancellation in Association with LB Fan-shaped Jets
Authors: Lim Eun-Kyung , Yang Heesu , Yurchyshyn Vasyl , Chae Jongchul , Song Donguk , Madjarska Maria S. 
Published: November 2020

Abstract
Light bridges (LBs) are relatively bright structures that divide sunspot umbrae into two or more parts. Chromospheric LBs are known to be associated with various activities including fan-shaped jet-like ejections and brightenings. Although magnetic reconnection is frequently suggested to be responsible for such activities, not many studies present firm evidence to support the scenario. We carry out magnetic field measurements and imaging spectroscopy of an LB where fan-shaped jet-like ejections occur with co-spatial brightenings at their footpoints. We study LB fine structure and magnetic field changes using TiO images, Near-InfraRed Imaging Spectropolarimeter, and Hα data taken by the 1.6 m Goode Solar Telescope. We detect magnetic flux emergence in the LB that is of opposite polarity to that of the sunspot. The new magnetic flux cancels with the pre-existing flux at a rate of 5.6 × 1018 Mx hr−1. Both the recurrent jet-like ejections and their base brightenings are initiated at the vicinity of the magnetic flux cancellation, and show apparent horizontal extension along the LB at a projected speed of up to

km s−1 to form a fan-shaped appearance. Based on these observations, we suggest that the fan-shaped ejections may have resulted from slipping reconnection between the new flux emerging in the LB and the ambient sunspot field.
Female sex worker : circulation et impact d’une catégorie de santé publique au Vanuatu
Authors: Servy Alice 
Published: November 2020

La catégorie de santé publique female sex worker (ou « travailleuse du sexe » en français) bénéficie aujourd’hui d’un essor transnational. Cet article montre non seulement les manières dont l’expression female sex worker est utilisée dans l’archipel mélanésien du Vanuatu, mais révèle également les conséquences socio-culturelles possibles de son usage pour les personnes concernées.
Intellectual capital and its impact on business performance: An empirical study of Portuguese hospitality and tourism sector
Authors: Costa Vânia , Silva Lurdes , Paula Loureiro 
Published: November 2020

Purpose: The propose of this study is to determine the influence of Intellectual Capital (IC) and its components’ impact on Portuguese tourism organizations’ business performance through Return on the assets (ROA). This work evaluate and compare the intellectual capital in its four dimensions: (i) capital employed; (ii) human capital; (iii) structural capital and (iv) relational capital. Design/methodology/approach: To approach the aim of the study the method Value Added Intellectual Coefficient (VAICTM) was applied and the practical data were collected from the Simplified Business Information (IES) through SABI (Iberian Balance Sheet Analysis System) database. The economic and financial information was collected from balance sheets and financial reports of 46.951 Portuguese companies in the hospitality and tourism sector during 2016. Multiple regression analysis was employed to identify the effect of IC components’ that significantly contribute to the company performance.Findings: The paper reveals that VAICTM, human capital efficiency coefficient (HCE), capital employed efficiency coefficient (CEE).and ROA are positively related among Portuguese’s hospitality and tourism sector. However, the structural capital efficiency coefficient (SCE) presents a negative association with profitability and the results of the relationship between the variable relational efficiency coefficient (RCE) and ROA do not present statistical significance.Practical implications: The application of the VAICTM model presented in this paper provides a basis for practical application for management.Originality/value: The paper represents a pioneering attempt to understand the relationship of intellectual capital and ﬁrm’s proﬁtability on Portuguese hospitality and tourism sector’s, to provide solid recommendations for the importance of intellectual capital in the sustainable growth of organizations in this sector.
La politique de la France à l’égard de l’Ukraine
Authors: Kosyk Wolodymyr 
Published: November 2020

A l’aide de documents d’archives, l’étude traite de la politique de la France à l’égard de la République ukrainienne, fondée en 1917, à l’époque où voulant sauver le front oriental, Paris cherchait à s’allier les forces nationales de l’empire russe éclaté è la suite de la Révolution. L’ouvrage apporte un nombre important de faits inconnus concernant les circonstances dans les- quelles se nouaient les relations franco-ukrainiennes, qui ont abouti à la nomination d’un Commissaire de la République française en Ukraine. Ces relations furent interrompues en raison de la guerre soviéto-ukrainienne et des pourparlers à Brest-Litovsk, qui allaient bouleverser la situation et provoquer le départ de la Mission française de Kiev. L’ouvrage contient également des informations sur le mouvement national ukrainien et la question ukrainienne en France avant la Révolution russe.
IL-4 Treatment Mitigates Experimental Cerebral Malaria by Reducing Parasitemia, Dampening Inflammation, and Lessening the Cytotoxicity of T Cells
Authors: Wu Xianzhu , Thylur Ramesh P , Dayanand Kiran K , Punnath Kishore , Norbury Christopher C , Gowda D Channe 
Published: November 2020

Abstract
Cytokine responses to malaria play important roles in both protective immunity development and pathogenesis. Although the roles of cytokines such as TNF-α, IL-12, IFN-γ, and IL-10 in immunity and pathogenesis to the blood stage malaria are largely known, the role of IL-4 remains less understood. IL-4 targets many cell types and induces multiple effects, including cell proliferation, gene expression, protection from apoptosis, and immune regulation. Accordingly, IL-4 has been exploited as a therapeutic for several inflammatory diseases. Malaria caused by Plasmodium falciparum manifests in many organ-specific fatal pathologies, including cerebral malaria (CM), driven by a high parasite load, leading to parasite sequestration in organs and consequent excessive inflammatory responses and endothelial damage. We investigated the therapeutic potential of IL-4 against fatal malaria in Plasmodium berghei ANKA–infected C57BL/6J mice, an experimental CM model. IL-4 treatment significantly reduced parasitemia, CM pathology, and mortality. The therapeutic effect of IL-4 is mediated through multiple mechanisms, including enhanced parasite clearance mediated by upregulation of phagocytic receptors and increased IgM production, and decreased brain inflammatory responses, including reduced chemokine (CXCL10) production, reduced chemokine receptor (CXCR3) and adhesion molecule (LFA-1) expression by T cells, and downregulation of cytotoxic T cell lytic potential. IL-4 treatment markedly reduced the infiltration of CD8+ T cells and brain pathology. STAT6, PI3K–Akt–NF-κB, and Src signaling mediated the cellular and molecular events that contributed to the IL-4–dependent decrease in parasitemia. Overall, our results provide mechanistic insights into how IL-4 treatment mitigates experimental CM and have implications in developing treatment strategies for organ-specific fatal malaria.
Il laboratorio del Comitato Etico - 2. La scheda informativa e il modulo di consenso alla sperimentazione clinica
Authors: Spagnolo A.G. , Minacori R. , Sacchini D. , Bignamini A.A. 
Published: November 2020

Nell’ambito della serie di articoli sul Laboratorio del Comitato Etico, il presente contributo affronta il tema della preparazione e della valutazione da parte del comitato etico della scheda informativa e del modulo di consenso informato per il soggetto al quale si chiede di partecipare ad uno studio clinico.
Tali documenti costituiscono, infatti, uno degli elementi indispensabili di un protocollo di sperimentazione, molto frequentemente oggetto di revisione critica da parte del CE anche perché secondo la normativa vigente in Italia è l’unica parte del protocollo modificabile sempre secondo le esigenze del singolo CE, anche nel caso delle sperimentazioni multicentriche.
Dopo una breve introduzione sugli aspetti generali del rapporto tra Comitati etici e valutazione del consenso informato, vengono passati in rassegna i principali documenti internazionali di riferimento per l’etica della sperimentazione clinica e le normative vigenti in Italia, nonché le indicazioni da esse fornite agli sperimentatori e ai CE riguardo la stesura della scheda informativa e del modulo di consenso.
Successivamente, dopo un confronto tra le versioni del 1991 e del 1996 delle Good Clinical Practice (GCP) riguardo al tema in oggetto, vengono offerte - anche alla luce della letteratura disponibile - indicazioni e suggerimenti su contenuti ed editing della scheda informativa/modulo di consenso, le quali possono contribuire all’ottimizzazione della stesura di tali documenti.
In appendice viene, infine, fornito un facsimile finalizzato ad aiutare la redazione di tali documenti, sia per l’inclusione di soggetti adulti capaci di consenso, sia di minori o comunque incapaci di consenso personale. Viene comunque lasciato allo sperimentatore o allo sponsor il compito di miglioramenti e adattamenti secondo la propria creatività e secondo le particolari esigenze che i singoli protocolli comportano.
Il rapporto tra Etica e Diritto nella Enciclica <em>Evangelium vitae</em>
Authors: Herranz Julián 
Published: November 2020

In questo articolo l’Autore ha voluto sottolineare l’importanza dell’Enciclica Evangelium Vitae nel risvegliare le coscienze contro uno dei più gravi capovolgimenti etici e giuridici della storia umana. L’intento è quello di esaminare tre questioni: 1) risalire alle basi sulle quali si fondava e si fonda il postulato giuridico e morale dell’inalienabilità del diritto alla vita dell’uomo innocente e, soprattutto, del concepito; 2) stabilire le cause che hanno portato ad una legislazione permissiva dell’aborto ed ad altri attentati contro la dignità dell’uomo e della vita umana (eutanasia, manipolazioni di geni ed embrioni…); 3) valutare quali siano i motivi filosofici e biologici la cui presa di coscienza sembri più necessaria per la tutela del diritto alla vita.
Intento dell’Autore è, per ciò che riguarda il diritto alla vita, sottolineare l’importanza che il principio di non discriminazione, basato su quello dell’uguaglianza, venga applicato all’“essere umano”, all’“individuo umano” e non soltanto alla “persona giuridicamente riconosciuta”.
L’articolo si sofferma, inoltre, ad illustrare la grande tradizione del diritto alla vita, il preoccupante regresso della civiltà giuridica, la necessità di un più stretto rapporto tra Diritto e Morale e Biologia e Morale (come campi di ricerca e di impegno intellettuale a difesa della vita).
Sustentabilidad de la producción de quinua en Ñahuimpuquio, Tayacaja
Authors: Contreras Liza Sergio Eduardo , Valenzuela Muñoz Alberto , Medina Castro Dario Emiliano , Torres Huamaní José , Morales Paredes Waldo 
Published: November 2020

Determinar el nivel de sustentabilidad de la producción de quinua en el distrito de Ñahuimpuquio, provincia de Tayacaja, Huancavelica Metodología: La investigación se realizó en el distrito de Ñahuimpuquio, provincia de Tayacaja, región Huancavelica, entre los 3 650 a 3 800 msnm. Se utilizó una encuesta a los productores de quinua mediante un cuestionario para obtener información de las variables e indicadores de sustentabilidad, siendo el número de entrevistados de 76 productores. Se aplicó la metodología de Sarandon que considera indicadores y subindicadores de sustentabilidad en 3 dimensiones: económica, ambiental y social. Se usó una escala cuantitativa de 0 (muy pobre sustentabilidad) hasta 4 (alto nivel de sustentabilidad). Resultados: Las fincas productoras de quinua tuvieron una calificación de 1,87 equivalente a una débil sustentabilidad ambiental, la sustentabilidad económica un valor de 1,72 y la sustentabilidad social obtuvo una valoración de 2,14. Se estimó el valor medio de los indicadores de sustentabilidad ambiental, económico y social, siendo el índice de sustentabilidad general de 1,91 indicando un valor debajo del umbral. Conclusiones: Las fincas productoras de quinua en el distrito de Ñahuimpuquio, presentaron una débil sustentabilidad implicando que ello podría constituirse en una amenaza para la producción sostenible de la quinua.