bluuebunny/crossref_metadata_2025_split huggingface dataset:
The reduced proper motion selected halo: Methods and description of the catalogue
Authors: Koppelman Helmer H. , Helmi Amina 
Published: November 2020

Context. The Gaia mission has provided the largest ever astrometric chart of the Milky Way. Using it to map the Galactic halo is helpful for disentangling its merger history.
Aims. The identification of halo stars in Gaia DR2 with reliable distance estimates requires special methods because such stars are typically farther away and scarce.
Methods. We applied the reduced proper motion method to identify halo main sequence stars on the basis of Gaia photometry and proper motions. Using the colour-absolute-magnitude relation for this type of star, we calculated photometric distances. Our selection results in a set of ∼107 tentative main sequence halo stars with typical distance uncertainties of 7% and with median velocity errors of 20 km s−1. The median distance of our sample is ∼4.4 kpc, with the faintest stars located at ∼16 kpc.
Results. The spatial distribution of the stars in our sample is centrally concentrated. A visual inspection of the mean velocities of stars on the sky reveals large-scale patterns as well as clear imprints of the GD-1 stream and tentative hints of the Jhelum and Leiptr streams. Incompleteness and selection effects limit our ability to interpret the patterns reliably as well as to identify new substructures. We define a pseudo-velocity space by setting the line-of-sight velocities of our sample stars to zero. In this space, we recover several known structures such as the footprint of Gaia-Enceladus (i.e., the Gaia-Sausage) as well as the Helmi Streams and some other retrograde substructures (Sequoia, Thamnos). We show that the two-point velocity correlation function reveals significant clustering on scales smaller than 100 km s−1 of a similar amplitude as found for the 6D Gaia halo sample. This clumping of stars in velocity space might hint at the presence of nearby streams that are predominantly phase-mixed.
Conclusions. A spectroscopic follow-up of our halo main sequence sample is bound to yield unprecedented views of Galactic history and dynamics. In future Gaia data releases, the level of systematics will be reduced and the astrometry will be more precise, which will allow for the identification of more substructures at larger distances.
Accretion bursts in magnetized gas-dust protoplanetary disks
Authors: Vorobyov Eduard I. , Khaibrakhmanov Sergey , Basu Shantanu , Audard Marc 
Published: November 2020

Aims. Accretion bursts triggered by the magnetorotational instability (MRI) in the innermost disk regions were studied for protoplanetary gas-dust disks that formed from prestellar cores of a various mass Mcore and mass-to-magnetic flux ratio λ.
Methods. Numerical magnetohydrodynamics simulations in the thin-disk limit were employed to study the long-term (~1.0 Myr) evolution of protoplanetary disks with an adaptive turbulent α-parameter, which explicitly depends on the strength of the magnetic field and ionization fraction in the disk. The numerical models also feature the co-evolution of gas and dust, including the back-reaction of dust on gas and dust growth.
Results. A dead zone with a low ionization fraction of x≲10−13 and temperature on the order of several hundred Kelvin forms in the inner disk soon after its formation, extending from several to several tens of astronomical units depending on the model. The dead zone features pronounced dust rings that are formed due to the concentration of grown dust particles in the local pressure maxima. Thermal ionization of alkaline metals in the dead zone trigger the MRI and associated accretion burst, which is characterized by a sharp rise, small-scale variability in the active phase, and fast decline once the inner MRI-active region is depleted of matter. The burst occurrence frequency is highest in the initial stages of disk formation and is driven by gravitational instability (GI), but it declines with diminishing disk mass-loading from the infalling envelope. There is a causal link between the initial burst activity and the strength of GI in the disk fueled by mass infall from the envelope. We find that the MRI-driven burst phenomenon occurs for λ = 2–10, but diminishes in models with Mcore ≲ M⊙, suggesting a lower limit on the stellar mass for which the MRI-triggered burst can occur.
Conclusions. The MRI-triggered bursts occur for a wide range of mass-to-magnetic flux ratios and initial cloud core masses. The burst occurrence frequency is highest in the initial disk formation stage and reduces as the disk evolves from a gravitationally unstable to a viscous-dominated state. The MRI-triggered bursts are intrinsically connected with the dust rings in the inner disk regions, and both can be a manifestation of the same phenomenon, that is to say the formation of a dead zone.
Intersecting Vulnerabilities: The Impacts of COVID-19 on the Psycho-emotional Lives of Young People in Low- and Middle-Income Countries
Authors: Banati Prerna , Jones Nicola , Youssef Sally 
Published: November 2020

AbstractAcross diverse contexts, emerging evidence suggests that the COVID-19 pandemic is increasing levels of anxiety and stress. In calling for greater attention to people’s psychosocial and emotional well-being, global actors have paid insufficient attention to the realities of the pandemic in low- and middle-income countries, where millions of people are already exposed to intersecting vulnerabilities. Chronic poverty, protracted violence, conflict and displacement, coupled with weak health, education and protection systems, provide the backdrop of many adolescents’ lives. Drawing on qualitative in-country telephone interviews with over 500 adolescents in Ethiopia, Côte d’Ivoire and Lebanon, this article unpacks the age and gendered dimensions of COVID-19 and its response. We conclude by discussing the implications for COVID-19 recovery efforts, arguing that embedding adolescent-centred, inclusive approaches in education, community-based health and social protection responses, has the potential to mitigate the psycho-emotional toll of the pandemic on young people and promote resilience.
A typology of healthcare interpreter positionings
Authors: René de Cotret François , Brisset Camille , Leanza Yvan 
Published: November 2020

Abstract
The conceptual vagueness surrounding the role of the public service interpreter can hinder collaboration between
interpreters and providers. Inspired by Mason’s work on interpreter positioning, the study aimed to clarify providers’ expectations of the
role of the interpreter in order to strengthen interprofessional collaboration. A typological analysis was conducted based on 23 healthcare
providers’ perceptions of the public service interpreter. The Typology of Healthcare Interpreter Positionings features eight positionings
that reinforce the interprofessional collaboration and nine that compromise it. The result is a concrete portrait that depicts the
neutrality of the public service interpreter as a powerful driver of collaboration. Providers also agree that interpreters must be able to
take their place in the consultation, even if it means being assertive and modifying the discourse of the interlocutors. Navigating such
situations while maintaining the provider’s trust requires interactional knowledge (soft skills), which complements technical knowledge
(hard skills). The Typology represents a communication tool that both providers and interpreters can use to foster collaboration. It also
represents a professionalization tool as it reiterates the importance of neutrality in the work of public service interpreters and their
social positioning as professionals.
Incoming Medical Students’ Knowledge of and Attitudes Toward People with Substance use Disorders: Implications for Curricular Training
Authors: Moses Tabitha E. , Chammaa May , Ramos Rafael , Waineo Eva , Greenwald Mark K. 
Published: November 2020

Background Medical students may be in an ideal position to identify patients with substance use disorders (SUDs) and provide them with information about harm reduction and treatment options. Specific education regarding opioid use disorder (OUD) and naloxone during undergraduate medical training may help students identify these patients and decrease their own negative attitudes toward patients with OUD. To plan for curriculum development, this study aimed to understand baseline knowledge and attitudes among students entering medical school. Methods During orientation, all first-year medical students (Class of 2023) were asked to complete a survey that explored their previous experiences in healthcare and with SUDs as well as their attitudes toward opioid overdose and patients with SUDs. We administered the Opioid Overdose Knowledge Scale (OOKS), Opioid Overdose Attitudes Scale (OOAS), Medical Conditions Regard Scale (MCRS), and Naloxone Related Risk Compensation Beliefs (NaRRC-B). Results 266 students (89.6% of the class) completed the survey. Generally, these students were relatively proficient in opioid overdose knowledge, but did not feel they were competent enough to respond to an overdose. Attitudes toward patients with SUDs were mixed. Approximately half of the students thought naloxone distribution should be unrestricted, but many were uncertain whether naloxone receipt would deter individuals from seeking treatment or increase opioid use. Students’ previous experiences in healthcare (e.g., employment) results in significantly different knowledge and attitudes toward opioid overdose response. Conclusions These incoming medical students have greater healthcare experience and level of opioid overdose knowledge than the general population, but still harbor significant misinformation and stigma toward patients with SUDs. These findings provide a foundation upon which to tailor didactic efforts, starting early in medical school, so that graduating physicians can be adequately prepared for clinical care.
Neoliberalism, welfare, and mass male circumcisions in Turkey
Authors: Başaran Oyman 
Published: November 2020

ABSTRACT
This article explores the neoliberalization of mass male circumcisions, a type of social assistance in Turkey. Male circumcision is a religious and medical practice widely performed in Muslim-majority Turkey, and when this procedure is organised for the poor in large numbers, it is referred to as mass male circumcisions. The article argues that since the 2000s, the AKP (Justice and Development Party) has neoliberalized mass male circumcision by transforming it into an economic and symbolic resource for competing hospitals as well as shaping the ‘deserving’ urban poor families into consumer-like actors. The article further shows the limits and contradictions of this process. In doing so, it challenges the binary between neoliberalism and welfare, and views social assistance as another potential site of neoliberalization that recrafts the society and the state in the image of the market, cutting across economic and non-economic spheres.
Manifold properties from causal sets using chains
Authors: Kambor Joachim , X Nomaan 
Published: November 2020

Abstract
We study the utility of chains defined on causal sets in estimating continuum properties like the curvature, the proper time and the spacetime dimension through a numerical analysis. In particular, we show that in dS
2 and FLRW3 spacetimes the formalism of Roy M et al 2013 Phys. Rev. D
87 044046 with slight modifications gives the right continuum properties. We also discuss a possible test of manifoldlikeness using this formalism by considering two models of non-manifoldlike causal sets. This is a part of a broader idea of the geometrical reconstruction of continuum properties given a discrete sub structure, in this case the causal set.
A connection between the ice-type model of Linus Pauling and the three-color problem
Authors: da Silva Roberto , Nakao Osvaldo S , de Felício J R Drugowich 
Published: November 2020

Abstract
The ice-type model proposed by Linus Pauling to explain its entropy at low temperatures is here approached in a didactic way. We first present a theoretically estimated low-temperature entropy and compare it with numerical results. Then, we consider the mapping between this model and the three-colour problem, i.e. colouring a regular graph with coordination equal to 4 (a two-dimensional lattice) with three colours, for which we apply the transfer-matrix method to calculate all allowed configurations for two-dimensional square lattices of N oxygen atoms ranging from 4 to 225. Finally, from a linear regression of the transfer matrix results, we obtain an estimate for the case N → ∞ which is compared with the exact solution by Lieb.
Ultrasound modulated bioluminescence tomography with a single optical measurement
Authors: Chung Francis , Yang Tianyu , Yang Yang 
Published: November 2020

Abstract
Ultrasound modulated bioluminescence tomography is an imaging method which can be formulated as a hybrid inverse source problem. In the regime where light propagation is modeled by a radiative transfer equation, previous approaches to this problem require large numbers of optical measurements (Bal et al 2016 SIAM J. Math. Anal.
48 1332). Here we propose an alternative solution for this inverse problem which requires only a single optical measurement in order to reconstruct the isotropic source. Specifically, we derive two inversion formulae based on Neumann series and Fredholm theory respectively, and prove their convergence under sufficient conditions. The resulting numerical algorithms are implemented and experimented to reconstruct both continuous and discontinuous sources in the presence of noise.
On topological classification of Morse–Smale diffeomorphisms on the sphere S

n
(n > 3)
Authors: Grines V , Gurevich E , Pochinka O , Malyshev D 
Published: November 2020

Abstract
We consider the class G(S

n
) of orientation preserving Morse–Smale diffeomorphisms of the sphere S

n
of dimension n > 3, assuming that invariant manifolds of different saddle periodic points have no intersection. For any diffeomorphism f ∈ G(S

n
), we define a coloured graph Γ
f
that describes a mutual arrangement of invariant manifolds of saddle periodic points of the diffeomorphism f. We enrich the graph Γ
f
by an automorphism P

f
induced by dynamics of f and define the isomorphism notion between two coloured graphs. The aim of the paper is to show that two diffeomorphisms f, f′ ∈ G(S

n
) are topologically conjugated if and only if the graphs Γ
f
, Γ
f
′ are isomorphic. Moreover, we establish the existence of a linear-time algorithm to distinguish coloured graphs of diffeomorphisms from the class G(S

n
).
Full thermal characterization of AlGaN/GaN high electron mobility transistors on silicon, silicon carbide, and diamond substrates using a reverse modeling approach
Authors: El-Helou A , Cui Y , Tadjer M J , Anderson T J , Francis D , Feygelson T , Pate B , Hobart K D , Raad P E 
Published: November 2020

Abstract
Gallium nitride (GaN) high electron mobility transistors (HEMTs) operate at high power levels and are thus especially thermally-critical devices. Not only do they require innovative thermal management strategies, but can also benefit from advanced experimental thermal characterization, both numerical and experimental, in their design and system integration stages. The thermal numerical analysis of microelectronic devices faces the challenges of complex physics and uncertain thermophysical properties which leads to numerically expensive models that are prone to error. By the use of an innovative reverse modeling approach to mitigate the above challenges, this work presents the full thermal characterization of GaN power devices with different substrates aimed at managing performance-limiting self-heating. The approach develops and optimizes a thermal simulation model to match the numerical results to experimentally-obtained thermal maps of the devices under test. The experimentally-optimized simulation model can then be used to extract full 3D temperature distributions, infer in-situ thermal properties, and provide a numerical platform that can be used to conduct further parametric studies and design iterations. The presented analysis provides a full thermal characterization of different GaN HEMT devices and compares the thermal performance of different substrates on the basis of thermal properties. The extracted properties for HEMTs on Si, SiC, and Diamond substrates are compared and a set of conclusions are presented to guide further developments in GaN HEMT thermal management strategies.
A high-efficiency energy regeneration shock absorber based on twin slider-crank mechanisms for self-powered sensors in railway cars
Authors: Li Lingbo , Wang Wei , Luo Dabing , Zhang Zutao , Qi Lingfei , Xie Li 
Published: November 2020

Abstract
In recent years, with the rapid increase of railway freight, various types of self-powered sensors have been widely used in intelligent electronic monitoring equipment and on-board electric equipment in order to improve the safety and transportation efficiency of railway freight during operation. In this paper, a type of energy regeneration shock absorber based on twin slider-crank mechanisms is developed to install on the auxiliary suspensions of railway cars parallel to the coil springs. The energy regeneration shock absorber is divided into four components, as follows: a suspension vibration energy input module, a transmission module, a generator module, and an energy storage module. The suspension vibration energy input module captures the vibration energy generated by the railway car suspension. The transmission module converts the linear motion of the shock absorber into the one-way rotation motion of the generator input shaft to generate electrical energy. The energy storage module stores the electricity in the super capacitor to supply energy to self-powered sensors in railway cars. According to the bench test of the MTS® fatigue testing system, the peak efficiency of the shock absorber is 56.4%, and the average efficiency is 42.9%. Under harmonic excitation with a frequency of 3 Hz and an amplitude of 12.5 mm, the peak phase power is 24.6 W and the average power is 4.8 W, showing that the proposed new energy regeneration shock absorber is effective and practical to apply to self-powered sensors in railway cars.
T
cs degradation of ITER TF samples due to fast current discharges
Authors: Sedlak Kamil , Bruzzone Pierluigi , Stepanov Boris , Mitchell Neil , Tronza Vladimir , Vostner Alexander 
Published: November 2020

Abstract
Direct current tests performed in the past on the conductor samples of the toroidal field (TF) ITER coils revealed degradation of current sharing temperature, T
cs. The degradation progresses with repetitive electromagnetic loading, and also with thermal cycles between 4.5 K and room temperature. This feature was observed on short samples in SULTAN test facility (EPFL-SPC, Switzerland) as well as in TF Insert Coil tests in CSMC test facility (Naka, Japan). We present three independent observations suggesting that initiation of sample quench followed by a fast current discharge, which normally complements every I
c and T
cs test in both SULTAN and CSMC, enhances the T
cs degradation rate. The exact mechanism of this contribution to the degradation remains unidentified.
Influence of strain-driven segregation in low-angle grain boundaries on critical current density of Y0.9Nd0.1Ba2Cu3O7-d
Authors: Kim Sang-il , Larbalestier David C 
Published: November 2020

Abstract
Low-angle grain boundaries (GBs) constitute the most important current-limiting mechanism in the operation of biaxially textured YBa2Cu3O7−d (YBCO)-coated conductors. Ca doping of YBCO is known to improve the critical current density J
c across the GB because of carrier doping by anisovalent Ca2+ substitution for Y3+ and the strain relief induced by Ca segregation at the GB cores; however, the reduction of the superconducting critical temperature T
c accompanying such doping is a marked drawback. Here we study the substitution of isovalent Nd3+ for Y3+ again using strain-driven segregation, in this case Nd3+, to improve J
c without incurring significant T
c reduction. Transport characteristics of low-angle GBs of 10% Nd-doped YBCO, Y0.9Nd0.1Ba2Cu3O7−d, grown on single crystal and 6° and 9° [001] tilt symmetric bicrystal SrTiO3 substrates are reported. It was found that J
c across the 6° GB recovers to the intra-grain J
c value in the 10% Nd-doped YBCO, while the 9° GB shows a modest J
c enhancement compared to the pure YBCO 9° GB without a significant T
c reduction. It is shown that the transparency of the GB could be enhanced without a large T
c reduction by the isovalent substitution of rare-earth ions, suggesting new opportunities for cation segregation engineering in YBCO by isovalent rare-earth substitution.
Optimum heat treatment to enhance the weak-link response of Y123 nanowires prepared by Solution Blow Spinning
Authors: Caffer Ana M , Chaves Davi A D , Pessoa Alexsander L , Carvalho Claudio L , Ortiz Wilson A , Zadorosny Rafael , Motta Maycon 
Published: November 2020

Abstract
Although the production of YBa2Cu3O7-δ (Y123) has been extensively reported, there is still a lack of information on the ideal heat treatment to produce this material in the form of one dimension nanostructures. Thus, by means of the Solution Blow Spinning technique, metals embedded in polymer fibers were prepared. These polymer composite fibers were fired and then investigated by thermogravimetric analysis. The maximum sintering temperatures of heat treatment were chosen in the interval 850 °C–925 °C for 1 h under oxygen flux. SEM images allowed us to determine the wire diameter as approximately 350 nm for all samples, as well as to map the evolution of the entangled wire morphology with the sintering temperature. XRD analysis indicated the presence of Y123 and secondary phases in all samples. Ac magnetic susceptibility and dc magnetization measurements demonstrated that the sample sintered at 925 °C/1 h is the one with the highest weak-link critical temperature and the largest diamagnetic response.
Research on the pricing of the double-competition closed-loop supply chain with uncertain recycling quantity
Authors: Han Mei , Liu Xiaowei 
Published: November 2020

Abstract
In order to solve the uncertainty impact of recycled products on pricing decision-making and financial intervention policy in double competition closed-loop supply chain, a pricing decision-making model is built by using the game theory and MATLAB numerical simulation. The model analyses and verifies the impact of the uncertain quantity upon the competition intensity, sale and recycling prices, supply chain node companies’ profits and social welfare, recovery rate of the closed-loop supply chain from four dimensions. The research results show that the recycling and repurchase prices are increasing when the quantity of recycled products shows significant fluctuation. The profit of social welfare and sellers are increasing, but manufacturer’s profit is decreasing, which means the uncertainty on recovery quantity directly affects the manufacturers, who play a leading role in implementing remanufacturing.