bluuebunny/crossref_metadata_2025_split huggingface dataset:
Keplerian disks and outflows in post-AGB stars: AC Herculis, 89 Herculis, IRAS 19125+0343, and R Scuti
Authors: Gallardo Cava I. , Gómez-Garrido M. , Bujarrabal V. , Castro-Carrizo A. , Alcolea J. , Van Winckel H. 
Published: March 2021

Context. There is a class of binary post-AGB stars with a remarkable near-infrared excess that are surrounded by Keplerian or quasi-Keplerian disks and extended outflows composed of gas escaping from the disk. The Keplerian dynamics had been well identified in four cases, namely the Red Rectangle, AC Her, IW Car, and IRAS 08544−4431. In these objects, the mass of the outflow represents ~10% of the nebular mass, the disk being the dominant component of the nebula.
Aims. We aim to study the presence of rotating disks in sources of the same class in which the outflow seems to be the dominant component.
Methods. We present interferometric NOEMA maps of 12CO and 13CO J = 2–1 in 89 Her and 12CO J = 2–1 in AC Her, IRAS 19125+0343, and R Sct. Several properties of the nebula are obtained from the data and model fitting, including the structure, density, and temperature distributions, as well as the dynamics. We also discuss the uncertainties on the derived values.
Results. The presence of an expanding component in AC Her is doubtful, but thanks to new maps and models, we estimate an upper limit to the mass of this outflow of ≲3 × 10−5 M⊙, that is, the mass of the outflow is ≲5% of the total nebular mass. For 89 Her, we find a total nebular mass of 1.4 × 10−2 M⊙, of which ~50% comes from an hourglass-shaped extended outflow. In the case of IRAS 19125+0343, the nebular mass is 1.1 × 10−2 M⊙, where the outflow contributes ~70% of the total mass. The nebular mass of R Sct is 3.2 × 10−2 M⊙, of which ~75% corresponds to a very extended outflow that surrounds the disk.
Conclusions. Our results for IRAS 19125+0343 and R Sct lead us to introduce a new subclass of binary post-AGB stars, for which the outflow is the dominant component of the nebula. Moreover, the outflow mass fraction found in AC Her is smaller than those found in other disk-dominated binary post-AGB stars. 89 Her would represent an intermediate case between both subclasses.
The Alfvénic nature of chromospheric swirls
Authors: Battaglia Andrea Francesco , Canivete Cuissa José Roberto , Calvo Flavio , Bossart Aleksi Antoine , Steiner Oskar 
Published: March 2021

Context.Observations show that small-scale vortical plasma motions are ubiquitous in the quiet solar atmosphere. They have received increasing attention in recent years because they are a viable candidate mechanism for the heating of the outer solar atmospheric layers. However, the true nature and the origin of these swirls, and their effective role in the energy transport, are still unclear.Aims.We investigate the evolution and origin of chromospheric swirls by analyzing numerical simulations of the quiet solar atmosphere. In particular, we are interested in finding their relation with magnetic field perturbations and in the processes driving their evolution.Methods.The radiative magnetohydrodynamic code CO5BOLD is used to perform realistic numerical simulations of a small portion of the solar atmosphere, ranging from the top layers of the convection zone to the middle chromosphere. For the analysis, the swirling strength criterion and its evolution equation are applied in order to identify vortical motions and to study their dynamics. As a new criterion, we introduce the magnetic swirling strength, which allows us to recognize torsional perturbations in the magnetic field.Results.We find a strong correlation between swirling strength and magnetic swirling strength, in particular in intense magnetic flux concentrations, which suggests a tight relation between vortical motions and torsional magnetic field perturbations. Furthermore, we find that swirls propagate upward with the local Alfvén speed as unidirectional swirls driven by magnetic tension forces alone. In the photosphere and low chromosphere, the rotation of the plasma co-occurs with a twist in the upwardly directed magnetic field that is in the opposite direction of the plasma flow. All together, these are clear characteristics of torsional Alfvén waves. Yet, the Alfvén wave is not oscillatory but takes the form of a unidirectional pulse. The novelty of the present work is that these Alfvén pulses naturally emerge from realistic numerical simulations of the solar atmosphere. We also find indications of an imbalance between the hydrodynamic and magnetohydrodynamic baroclinic effects being at the origin of the swirls. At the base of the chromosphere, we find a mean net upwardly directed Poynting flux of 12.8 ± 6.5 kW m−2, which is mainly due to swirling motions. This energy flux is mostly associated with large and complex swirling structures, which we interpret as the superposition of various small-scale vortices.Conclusions.We conclude that the ubiquitous swirling events observed in numerical simulations are tightly correlated with perturbations of the magnetic field. At photospheric and chromospheric levels, they form Alfvén pulses that propagate upward and may contribute to chromospheric heating.
Stellar clustering and orbital architecture of planetary systems
Authors: Adibekyan V. , Santos N. C. , Demangeon O. D. S. , Faria J. P. , Barros S. C. C. , Oshagh M. , Figueira P. , Delgado Mena E. , Sousa S. G. , Israelian G. , Campante T. , Hakobyan A. A. 
Published: March 2021

Context. Revealing the mechanisms shaping the architecture of planetary systems is crucial for our understanding of their formation and evolution. In this context, it has been recently proposed that stellar clustering might be the key in shaping the orbital architecture of exoplanets.
Aims. The main goal of this work is to explore the factors that shape the orbits of planets.
Methods. We performed different statistical tests to compare the properties of planets and their host stars associated with different stellar environments.
Results. We used a homogeneous sample of relatively young FGK dwarf stars with radial velocity detected planets and tested the hypothesis that their association to phase space (position-velocity) over-densities (“cluster” stars) and under-densities (“field” stars) impacts the orbital periods of planets. When controlling for the host star properties on a sample of 52 planets orbiting around cluster stars and 15 planets orbiting around field stars, we found no significant difference in the period distribution of planets orbiting these two populations of stars. By considering an extended sample of 73 planets orbiting around cluster stars and 25 planets orbiting field stars, a significant difference in the planetary period distributions emerged. However, the hosts associated with stellar under-densities appeared to be significantly older than their cluster counterparts. This does not allow us to conclude as to whether the planetary architecture is related to age, environment, or both. We further studied a sample of planets orbiting cluster stars to study the mechanism responsible for the shaping of orbits of planets in similar environments. We could not identify a parameter that can unambiguously be responsible for the orbital architecture of massive planets, perhaps, indicating the complexity of the issue.
Conclusions. An increased number of planets in clusters and in over-density environments will help to build large and unbiased samples which will then allow to better understand the dominant processes shaping the orbits of planets.
Relative field line helicity of a large eruptive solar active region
Authors: Moraitis K. , Patsourakos S. , Nindos A. 
Published: March 2021

Context. Magnetic helicity is a physical quantity of great importance in the study of astrophysical and natural plasmas. Although a density for helicity cannot be defined, a good proxy for this quantity is field line helicity. The appropriate quantity for use in solar conditions is relative field line helicity (RFLH).
Aims. This work aims to study in detail the behaviour of RFLH, for the first time, in a solar active region (AR).
Methods. The target AR is the large, eruptive AR 11158. In order to compute RFLH and all other quantities of interest, we used a non-linear force-free reconstruction of the AR coronal magnetic field of excellent quality.
Results. We find that the photospheric morphology of RFLH is very different than that of the magnetic field or electrical current, and this morphology is not sensitive to the chosen gauge in the computation of RFLH. The value of helicity experiences a large decrease, that is ∼25% of its pre-flare value, during an X-class flare of the AR; this change is also depicted in the photospheric morphology of RFLH. Moreover, the area of this change coincides with the area that encompasses the flux rope, which is the magnetic structure that later erupted.
Conclusions. The use of RFLH can provide important information about the value and location of the magnetic helicity expelled from the solar atmosphere during eruptive events.
A hepatitis B virus causes chronic infections in equids worldwide
Authors: Rasche Andrea , Lehmann Felix , Goldmann Nora , Nagel Michael , Moreira-Soto Andres , Nobach Daniel , de Oliveira Carneiro Ianei , Osterrieder Nikolaus , Greenwood Alex D. , Steinmann Eike , Lukashev Alexander N. , Schuler Gerhard , Glebe Dieter , Drexler Jan Felix ,   the Equid HBV Consortium, Aguilar-Setien Alvaro , Azab Walid , Carluccio Augusto , Dietrich Dimo , Franke Carlos Roberto , García-Bocanegra Ignacio , García-Lacy Fernando , Jeworoski Lara M. , Jores Jörg , Kepper Ramona , Netto Eduardo Martins , Owusu-Dabo Ellis , Ribas Jorge R.L. , Roncoroni Christina , Roppert Pia L. , Rusenov Anton , Rusenova Nikolina , Sandev Nikolay , Seeber Peter A. , Shnaiderman-Torban Anat , Steinman Amir , Tegtmeyer Birthe , Veneziano Vincenzo , Veronesi Maria C. , Walter Stephanie , Zapryanova Dimitrinka 
Published: March 2021

Significance
The development of urgently needed hepatitis B virus (HBV) treatments is challenged by the lack of suitable animal models. Here, we describe an HBV-related virus, which occurs globally in donkeys and zebras (Equid HBV, EqHBV). EqHBV presumably originated in Africa, approximately at the time when donkey domestication started. EqHBV causes a hepatotropic disease comparable to human HBV infection and prolonged infections, resembling chronic hepatitis B in humans. In vitro infection studies suggested that horses are also susceptible to EqHBV. Both donkeys and horses also host a hepatitis C virus (HCV)-like virus. EqHBV offers unique opportunities for in vivo studies of both chronic hepatitis B and HBV/HCV coinfections in terms of pathogenesis and therapy optimization.
Community presence, motivation, and identity
Authors: Amorati Riccardo 
Published: March 2021

AbstractThis study examines the extent to which the motivation of university students of Italian in Melbourne (Australia) is influenced by the visibility of a local Italian community. The research relies on data collected by open-ended questions and two Likert items from a survey study (n = 74) as well as in-depth interviews (n = 5). The findings show that learners’ motivation is influenced by their exposure to the L2 language and culture in the local context and by their engagement with a community that forms part of Australia’s culturally and linguistically diverse population. Students’ investment in the L2 can be interpreted in light of a new identity dimension, the community-engaged L2 self, which builds upon previous motivational variables (integrative orientation, ideal L2 self), as well as scholarly insights into the link between language, identity, and access to L2 resources. This self-characterizes both heritage and non-heritage learners’ positioning through the L2 in the local socio-context and is expected to hold considerable pedagogical significance.
Beyond base and collocate
Authors: Cantos Pascual , Almela-Sánchez Moisés 
Published: March 2021

AbstractSupport verb constructions figure among the most frequently investigated topics in the literature on collocation. So far, most studies of this kind have focused on bipartite structures, consisting of a verbal collocate and a nominal base. Accordingly, the analysis of how support verbs are distributed has concentrated almost exclusively on the lexical control exerted by the base. In this article, we draw attention towards the influence exerted by the participation of verb and noun in more complex patterns of lexical co-occurrence. We contend that the distribution of the support verb collocate is contingent not only on the base noun but also on other elements of the lexical context. This highlights the need to enrich the theoretical framework of collocation analysis with the additional descriptive category of ‘second-order collocate’. The proposal is illustrated with two case studies using a large-scale web corpus of English.
Retrieving the new from the legacy of history
Authors: Çakmak Alper , Özekmekçi M. İnanç 
Published: March 2021

AbstractContemporary Turkey has gone through many reforms that have been legitimized by country’s historical legacy. The constitutive elements of this legacy are images, historical figures, events, and symbolisms embedded in memory. It is through those elements that Recep Tayyip Erdoğan, the leader of the Justice and Development Party sets himself up as the appropriate narrator and appropriate doer, incrementally gaining an upper hand in the legitimacy struggles by telling stories from history, emerging as the new founding father of Turkey and introducing new policies rooted in the legacy of the past. How has he been able to occupy such a position of superiority through the struggles for legitimacy in Turkish politics? This paper critically argues that Erdoğan first set up his personality, imposing himself as the most appropriate narrator and finally showing himself to be the most appropriate doer, by crafting his political communication with symbols and figures from history.
English and multilingual repertoires in healthcare
Authors: Mlambo Nelson 
Published: March 2021

Abstract
This chapter investigates the role of English in
the communicative practices among multilingual participants in
healthcare in Windhoek, Namibia, from the perspective of expatriate
healthcare practitioners working in the private sector. It provides
insights into the use of English in Namibia and informs about the
multilingual communicative resources and needs from the perspective
of healthcare providers (HCPs). The chapter illustrates that
expatriate multilingual HCPs, working in a multilingual context,
find the linguistic diversity at their workplace both challenging
and enriching. They experience the use of English and many other
languages to be an engagement that broadens their professional,
social, and cultural views and this ultimately results in improved
work relations and improved HCP-patient relationships.
A variational pragmatic approach to responses to thanks in
Namibian English
Authors: Schröder Anne , Schneider Klaus P. 
Published: March 2021

Abstract
Variational pragmatics has only recently been
combined with non-native World Englishes research, by examining the
pragmatics of Namibian English (NamE). However, this research has
concentrated on the comparison of pragmatic phenomena in NamE to
those in some L1-varieties, exclusively based on the same mixed-task
questionnaire. Although this has led to the discovery of
specifically Namibian usages, limitations to the validity of this
type of data collection have been pointed out. This chapter
triangulates the results of a quantitative questionnaire study with
qualitative analysis of role-plays and meta-pragmatic focus group
discussions, reassessing earlier findings on responses to thanks in
NamE. This contributes to the understanding of sociolinguistic
complexity and the negotiation of pragmatic strategies in the
multilingual ecology of Namibia.
Namibian literature in English
Authors: Frank Kerstin 
Published: March 2021

Abstract
This essay provides a survey of Namibian
literature written in English both before and after independence in
1990, but with a focus on post-independence writing. The survey is
structured by genre categories, starting with autobiographies,
novels and short stories and continuing with drama and poetry. In
each section, important authors and anthologies are briefly named
and selected works are given more detailed attention. While aiming
at a general overview of Namibian literature, this essay puts
particular focus on the way the texts negotiate the topic of
personal and national identity, either with reference to the
country’s colonial past and the liberation struggle or regarding
contemporary society and its social inequalities, contrasts and
cultural diversity.
Structured Professional Judgment (SPJ) Violence Risk Case Formulation and Psychopathic Personality Disorder
Authors: Gatner Dylan T. , Douglas Kevin S. , Hart Stephen D. , Kropp P. Randall 
Published: March 2021

The bivariate, empirical association between psychopathic personality disorder (PPD) and violence has been well established. Yet, questions remain about how to explain why this association occurs. To address this conceptual gap, we presented a review of theories of violence related to PPD. Next a conceptual analysis of how psychopathic traits may influence violent decisions was conducted. Specifically, we systematically analyzed how Comprehensive Assessment of Psychopathic Personality (CAPP; Cooke et al., International Journal of Forensic Mental Health, 11(4), 242–252, 2012) traits influence violence from a structured professional judgment (SPJ) theory of violence known as SPJ decision theory. This conceptual analysis clarifies how various CAPP traits may motivate, disinhibit, or destabilize violence. Implications include the role of causality and clinical applications of violence risk case formulations.
Bilateral comparison of 1 Ω and 10 kΩ standards (ongoing BIPM key comparisons BIPM.EM-K13.a and 13.b) between the EMI (United Arab Emirates) and the BIPM
Authors: Rolland B , Stock M , Gournay P , Bartholomew J , Kalbani W Al , Kayyoomi S Al 
Published: March 2021

Main text
This report gives the result of a bilateral comparison of resistance between the EMI (United Arab Emirates) and the BIPM carried out in 2020. Two 1 Ω and two 10 kΩ travelling standards belonging to the BIPM were used. The comparison was carried out with an 'A-B-A' pattern of measurements; the standards were measured first at the BIPM for a period of about one month, then for a period of about one month at the EMI, and finally again at the BIPM. The measurand was the 4 terminal dc resistance at low power. The BIPM was the pilot laboratory, and the comparison forms part of the ongoing BIPM key comparisons BIPM.EM-K13.a (for 1 Ω) and BIPM.EM-K13b (for 10 kΩ).
The results from the EMI and the BIPM were found to be in good agreement, with a difference D smaller than the relative expanded uncertainty Uc (95% confidence, k = 2) giving D = -0.057 × 10-6, Uc = 0.400 × 10-6 for 1 Ω and D = 0.017 × 10-6, Uc = 0.194 × 10-6 for 10 kΩ.
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.
The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Detecting the event of a single photon loss on quantum signals
Authors: Mandilara A , Balkybek Y , Akulin V M 
Published: March 2021

Abstract
We design a scheme for detecting a single photon loss from multi-modal quantum signals transmitted via a fiber or in free space. This consists of a special type of unitary coding transformation, the parity controlled-squeezing, applied prior to the transmission on the signal composed by information and ancilla modes. At the receiver, the inverse unitary transformation is applied—decoding, and the ancilla mode is measured via photon detection. The outcome reveals whether a photon loss has occurred. Distortion of the information part of the signal caused by an ancilla photon loss can be corrected via unitary transformation while loss of a photon from the information part of the signal can be detected with the probability exponentially close to unity but cannot be corrected. In contrast to the schemes of decoherence free subspaces and quantum error correction protocols, this method allows one to make use in principle of entire Hilbert space dimensionality. We discuss possible ways of synthesizing the required encoding–decoding transformation.
High-sensitivity detection of Concanavalin A using MoS2-based field effect transistor biosensor
Authors: Ma Mingyang , Chao Lemeng , Zhao Yuhang , Ding Jiafeng , Huang Zhongchao , Long Mengqiu , Wang Fuliang , Jiang Jie , Liu Zhengchun 
Published: March 2021

Abstract
The specific interaction between sugar and lectin plays a key role in various human diseases and projects remarkable significance to the development of a lectin biosensor for diagnosis and drug discovery. An inorganic nano MoS2 field-effect transistor (FET)-based D-Mannose biosensor was developed in this paper using a simple assembly process. First, gold nanoparticles were functionalized on the surface of MoS2. Then, the β-mercaptoethylamine was self-assembled on the gold surface via Au–S bonds to derivatize amino groups. Finally, the probe molecules D-Mannose for biological protein were immobilized on the FET via the Schiff base reaction. Results from scanning electron microscope and x-ray photoelectron spectroscopy analysis confirmed the entire assembly procedure and the feasible interaction of the FET sensor with Concanavalin A (ConA). The fabricated FET biosensors can reliably detect the target ConA with a detection limit below 105 nm. The current study shows the potential of MoS2 FET biosensors for ConA specific detection and clarifies the design of biosensors for the early diagnosis of glycomics and drug screening in medicine.
Pentamode metamaterials with ultra-low-frequency single-mode band gap based on constituent materials
Authors: Huang Yan , Zhang Xiaozhe 
Published: March 2021

Abstract
An effective method for realizing ultra-low-frequency single-mode band gap in pentamode metamaterials is proposed based on constituent materials. Results show that the decreasing ratio E/ρ (stiffness/mass density) of constituent material can significantly lower the frequency range of single-mode band gap. By merely replacing the constituent material from Al to rubber, the center frequency f
c of single-mode band gap can be reduced nearly 600 times (from 3621 Hz to 6.5 Hz), while the normalized bandwidth Δf/f
c and the ratio of bulk modulus B to shear modulus G of pentamode structure keep substantially stable. The nonlinear fitting demonstrates that the relation between f
c and E/ρ satisfies the logarithmic function. The two-component pentamode structure is designed to further explore the ultra-low-frequency single-mode band gap. The effects of thick-end diameter D of double-cone, diameter D
0 and material type of additional sphere, on single-mode band gap of two-component system are analyzed. This work is attractive for several ∼Hz acoustic/elastic wave regulations using pentamode metamaterials.