bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic and thermal acceleration in extragalactic jets
Authors: Ricci L. , Perucho M. , López-Miralles J. , Martí J. M. , Boccardi B. 
Published: January 2024

Aims. Relativistic jets launched from active galactic nuclei accelerate up to highly relativistic velocities within a length scale of between a few parsecs and tens of parsecs. The precise way in which this process takes place is still unclear. While magnetic acceleration is known to be able to accelerate relativistic outflows, little attention has been paid to the role of thermal acceleration. The latter has been assumed to act only on compact regions very close to the central engine, and to become negligible on parsec scales. However, this holds under the assumption of small internal energies relative to the magnetic ones, and whether or not this assumption is valid and what happens when we drop this assumption are open questions.
Methods. We used a 2D relativistic magnetohydrodynamical code to explore jet acceleration from subparsec to parsec scales. As initial conditions for our models, we used observational constraints on jet properties derived by means of very long-baseline interferometry observations for a Fanaroff Riley I radio galaxy, NGC 315. We investigated the parameter space established for this source and performed a number of simulations of magnetically, thermally, or kinetically dominated jets at injection, and compared our results with the observations. Furthermore, we employed different models to characterize our jets, involving different magnetic field configurations (i.e., force-free vs. nonforce-free) and varying shear layer thicknesses.
Results. Our simulated jets show that when thermal energy is comparable to or exceeds magnetic energy, thermal acceleration becomes significant at parsec scales. This result has important consequences, potentially extending the acceleration region far beyond the collimation scales, as thermal acceleration can effectively operate within a conically expanding jet. In all the models, we find acceleration to be driven by expansion, as expected. A number of our models allow us to reproduce the acceleration and opening angles observed in NGC 315. Finally, our results indicate that disk-launched winds might play an important role in jet propagation. Namely, when the jet has an initial force-free magnetic field configuration, thicker shear layers are needed to shield the internal spine from the action of the external medium and thus delay the growth of instabilities.
LeHaMoC: A versatile time-dependent lepto-hadronic modeling code for high-energy astrophysical sources
Authors: Stathopoulos S. I. , Petropoulou M. , Vasilopoulos G. , Mastichiadis A. 
Published: January 2024

Context. Recent associations of high-energy neutrinos with active galactic nuclei (AGN) have revived the interest in leptohadronic models of radiation from astrophysical sources. The rapid increase in the amount of acquired multi-messenger data will require fast numerical models that may be applied to large source samples.Aims. We develop a time-dependent leptohadronic code,LeHaMoC, that offers several notable benefits compared to other existing codes, such as versatility and speed.Methods.LeHaMoCsolves the Fokker-Planck equations of photons and relativistic particles (i.e. electrons, positrons, protons, and neutrinos) produced in a homogeneous magnetized source that may also be expanding. The code utilizes a fully implicit difference scheme that allows fast computation of steady-state and dynamically evolving physical problems.Results. We first present test cases where we compare the numerical results obtained withLeHaMoCagainst exact analytical solutions and numerical results computed with ATHEvA, a well-tested code of similar philosophy but a different numerical implementation. We find a good agreement (within 10–30%) with the numerical results obtained with ATHEvA without evidence of systematic differences. We then demonstrate the capabilities of the code through illustrative examples. First, we fit the spectral energy distribution from a jetted AGN in the context of a synchrotron-self Compton model and a proton-synchrotron model using Bayesian inference. Second, we compute the high-energy neutrino signal and the electromagnetic cascade induced by hadronic interactions in the corona of NGC 1068.Conclusions.LeHaMoCis easily customized to model a variety of high-energy astrophysical sources and has the potential to become a widely utilized tool in multi-messenger astrophysics.
The galactic bubbles of starburst galaxies
Authors: Meliani Z. , Cristofari P. , Rodríguez-González A. , Fichet de Clairfontaine G. , Proust E. , Peretti E. 
Published: January 2024

Context. The galactic winds of starburst galaxies (SBGs) give rise to remarkable structures on kiloparsec scales. However, the evolution and shape of these giant wind bubbles, as well as the properties of the shocks they develop, are not yet fully understood.
Aims. We aim to understand what shapes the galactic winds of SBGs, with a particular focus on the role of large-scale magnetic fields in the dynamical evolution of galactic wind-inflated bubbles. In addition, we aim to explore where the conditions for efficient particle acceleration are met in these systems.
Methods. We performed magnetohydrodynamic simulations with the AMRVAC code (Adaptive Mesh Refinement Versatile Advection Code) with various configurations of the galactic medium density profile and magnetization.
Results. We observe that the large-scale magnetic field, in which galactic winds expand, can impact the structure and evolution of inflated bubbles. However, the typical structures observed in starburst galaxies, such as M82, cannot be solely explained by the magnetic field structures that have been considered. This highlights the importance of other factors, such as the galactic disk, in shaping the galactic bubble. Furthermore, in all the magnetized cases we investigated, the forward wave resulting from the expanding bubbles only results in compression waves, whereas the wind termination shock features high Mach numbers, making it a promising site for diffusive shock acceleration up to ∼102 PeV. The synthetic X-ray images generated from our models reveal an envelope surrounding the bubbles that extends up to 2 kpc, which could correspond to the polarized emission observed from planar geometry in M82, as well as a large structure inside the bubble corresponding to the shocked galactic wind. Additionally, our findings indicate that, as observed with the SOFIA instrument, a large ordered magnetic field is associated with the free galactic wind, while a more turbulent magnetic field is present in the shocked region.
Accretion-induced flickering variability among symbiotic stars from space photometry with NASA TESS
Authors: Merc J. , Beck P. G. , Mathur S. , García R. A. 
Published: January 2024

Context. Symbiotic binaries exhibit a wide range of photometric variability across different timescales. These changes can be attributed to factors such as orbital motion, intrinsic variability of the individual components, or interactions between the two stars. In the range from minutes to hours, a variability induced by accretion processes that is likely to originate from the accretion disks has been detected and subsequently denoted as flickering. This variability could mimic solar-like oscillations exhibited by luminous red giants.
Aims. We aim to investigate whether it is possible to utilize the precise observations of the NASA TESS mission to detect flickering in symbiotic stars, despite the fact that such studies are usually performed at shorter wavelengths than those of TESS observations. Additionally, our goal is to develop a quantitative method for the detection of accretion-induced flickering that does not rely solely on a subjective assessment of the light curves.
Methods. We obtained the light curves of known symbiotic stars and a comprehensive control sample of assumed single red giants from the TESS full-frame images. To ensure consistency, all the data were processed using the same methodology, which involves filtering out the background, systematic, and long-term trends. From the processed light curves and their power spectral densities, we measured the amplitudes of the variability and other relevant parameters.
Results. We introduce a method that enables a differentiation between flickering sources and stars that do not exhibit this type of variability. We detected flickering-like variability in 20 symbiotic stars utilizing TESS data, of which 13 had not previously been identified as flickering sources. Moreover, the TESS observations facilitate the detection of related variations occurring over timescales of a few days, as well as changes in the flickering behavior across multiple sectors.
Conclusions. The flickering is now likely to be detected in a total of 35 known symbiotic stars. While this represents only a small subset of all symbiotic binaries, when focusing solely on accreting-only symbiotic stars where the detection of flickering is presumably more straightforward, the fraction could reach as high as ∼80%. This result suggests that accretion disks may indeed be prevalent in these binaries.
Solar extreme ultraviolet variability as a proxy for nanoflare heating diagnostics
Authors: Ulyanov Artem , Reva Anton , Kirichenko Alexey , Loboda Ivan , Bogachev Sergey 
Published: January 2024

Aims. We aim to improve the existing techniques to probe the nanoflare hypothesis for the coronal heating problem. For this purpose, we propose using the solar extreme ultraviolet (EUV) emission variability registered with modern space-based imagers.
Methods. We followed a novel model-based approach. As a starting point, we used the EBTEL 0d hydrodynamic model. We integrated the arising system of stochastic differential equations to calculate the covariance matrix for plasma parameters. We then employed a Taylor expansion technique to relate model parameters with observable EUV intensity variation statistics.
Results. We found that in the high-frequency approximation, the variability of the EUV emission is defined by the dimensionless factor ϖ, which is inversely proportional to the frequency. We calculated the factor ϖ throughout the solar disk and found that it does not exceed 0.01, except for the finite number of compact regions. The distribution of ϖ follows the power law with an index of ≈ − 2.6. To validate our approach, we used it to probe the temperature of the coronal plasma. We show that the line-of-sight temperature distribution is close to homogeneous with a mode of ≈1.25 MK, which is in perfect agreement with the results of the spectroscopic diagnostics.
Un cas de péricardite hémorragique aseptique idiopathique chez une vache Prim’Holstein de 3 ans
Authors: Collin Floriane 
Published: January 2024

Une vache Prim’Holstein de 3 ans, est référée le 17/11/2022 aux hôpitaux de médecine des animaux d’élevage d’Oniris pour suspicion de péricardite traumatique par corps étranger évoluant. Les signes évoluent depuis un mois et demi, avec dans un premier temps une chute en lait et un avortement à 7 mois de gestation. L’examen clinique met en évidence des signes marqués d’insuffisance cardiaque congestive droite, une atténuation bilatérale des bruits cardiaques, une matité des bruits respiratoires à droite crânio-ventralement, une diarrhée liquide malodorante sans éléments figurés et des signes de douleur ou d’inconfort.
Une échocardiographie révèle un épanchement péricardique anéchogène, de 10 cm de profondeur et une tamponnade. La mise en place d’un drain péricardique permet l’écoulement progressif de 5,5 litres d’un épanchement hémorragique inodore. Les analyses cytologiques et bactériologiques mettent en évidence un exsudat de type hémopéricarde inflammatoire aseptique pouvant correspondre à une péricardite idiopathique ou un traumatisme vasculaire au niveau du péricarde. Une échographie pulmonaire met en évidence un épanchement pleural focal anéchogène en portion crânio-ventrale à droite. L’analyse révèle un exsudat aseptique compatible avec une insuffisance cardiaque droite.
L’évolution est favorable : augmentation de l’appétit, disparition de la diarrhée en 3 jours, et réduction des signes d’insuffisance cardiaque droite après 10 jours. Les contrôles échocardiographiques montrent un épanchement stable de 2 cm de profondeur et une disparition de la tamponnade. Après un gain d’environ 30 kg, la vache est abattue, avec absence de saisie.
Direct-Acting Oral Anticoagulants in patients at extremes of body weight: a review of pharmacological considerations and clinical implications
Authors: Talerico Rosa , Pola Roberto , Klok Frederikus Albertus , Huisman Menno Volkert 
Published: January 2024

AbstractPatients at extremes of body weight are underrepresented in randomized controlled trials of direct-acting oral anticoagulants (DOACs). Therefore, their optimal anticoagulant treatment remains a topic of debate.The aim of this narrative review is to summarize the evidence on the pharmacokinetic and pharmacodynamic profile of DOACs for treating patients at extremes of body weight in venous thromboembolism (VTE) and in the prevention of cardioembolic stroke in nonvalvular atrial fibrillation (NVAF). A literature search was conducted in the main bibliographic databases, and the most relevant reviews and original articles on the topic were selected.Although data in these patient groups are limited, apixaban and rivaroxaban show a favorable pharmacokinetic and pharmacodynamic profile in obese VTE treatment and NVAF patients and, in the case of apixaban, also in underweight patients. In particular, these drugs demonstrated comparable efficacy and safety to standard therapy. Very few data were available for dabigatran and edoxaban; the latter drug was safer at a lower dose, mainly in underweight patients.Our findings are in line with the last International Society of Haemostasis and Thrombosis position paper and European Heart Rhythm Association 2021 practical guide, suggesting the use of apixaban and rivaroxaban in morbidly obese patients (>120 kg or body mass index ≥40 kg/m2) and the reduced dosage of edoxaban in low-weight patients. Future studies should focus on large populations of patients at extremes of body weights to acquire more clinical and pharmacokinetic evidence on all available DOACs, especially those currently less investigated.
A multiscale FEM-MD coupling method for investigation into atomistic-scale deformation mechanisms of nanocrystalline metals under continuum-scale deformation
Authors: Yamazaki Yusuke , Murashima Takahiro , Kouznetsova Varvara , Muramatsu Mayu 
Published: January 2024

Abstract
This study aims to develop a multiscale bridging method for investigating nanocrystalline metals based on macro-scale deformation. For this purpose, we propose a hierarchical multiscale computational method that can focus on some of the elements in a finite element model for scale bridging to atomistic-scale models. This method assumes that atomistic-scale nanocrystalline models are related to the integration points in a finite element and deform based on the macro-scale deformation. Nanocrystalline aluminum was chosen for the validation of the multiscale method. The finite element method (FEM) and the molecular dynamics (MD) method were used for continuum-scale and atomistic-scale simulations, respectively. We utilized the notion of the CauchyBorn rule (CBR) for communicating deformation information from the continuum scale to the atomistic scale. We studied three different cases with two nanocrystalline models and two loading cases to compare differences resulting from crystal structures and loading. Based on the crystal structure change during relaxation, nonequilibrium grain boundaries (NEGBs) were shown to play a role as deformation mechanisms in the plastic regime and induce the onset and migration of crystal defects, including deformation twins, as reported in the experiment. Furthermore, the crystal orientation dependence of the onset of crystal defects was confirmed by the comparison of the results from the two different nanocrystalline models. The qualitative agreement of the results with experimental observations is also confirmed. The proposed ‘FEM-MD’ method can bridge a large-scale gap, for example, from a nano-scale to a continuum-scale such that an MD model can be coupled to a millimeter or centimeter scale compared to other embedding methods. The present method is ideal for investigating the dislocation behavior of nanocrystalline materials, which contain multi-grained nanostructure at finite temperature, undergoing various loading scenarios at the macro-scale.
The first-principles study on the magnetic and electronic properties of Janus Cr-based MXene
Authors: Sun Qian , Zong Wanzhen , Yang Zongxian , Zhang Xilin 
Published: January 2024

Abstract
Using the first-principles calculations, the geometric, magnetic and electronic properties of two-dimensional Janus MXenes Cr2CAB (A/B = F, O, OH) were investigated. The results show that Cr2COF, Cr2CO(OH) and Cr2CF(OH) all exhibit A-type antiferromagnetic. The Janus MXene Cr2CO(OH) and Cr2COF are half metals with the atomic orbital of Cr-d and O-p states contributing to the metal states at the Fermi level in spin up channel. However, Cr2CF(OH) is a semiconductor. Bader charge and geometric structure analyses show that the electron transfer number difference between the O2- and F-/OH- groups and the bond length difference between Cr-O and Cr-OH/F lead to an unequal interaction at the two ends, resulting in a transition from semiconductor properties of Cr2CT2 (T = F, OH) to half metal of Cr2CAB (A = O; B = F, OH). These findings highlight the importance of surface groups on tuning the magnetic and electronic properties of MXene, which benefits to the applications of two-dimensional Janus MXenes in spintronics.
Efficient quantum simulation of open quantum system dynamics on noisy quantum computers
Authors: Sun Shin , Shih Li-Chai , Cheng Yuan-Chung 
Published: January 2024

Abstract
Quantum simulation represents the most promising quantum application to demonstrate quantum advantage on near-term noisy intermediate-scale quantum (NISQ) computers, yet available quantum simulation algorithms are prone to errors and thus difficult to realize with limited circuit depth on nowadays quantum devices. Herein, we propose a novel scheme to utilize intrinsic gate errors of NISQ devices to enable controllable simulation of open quantum system dynamics without ancillary qubits or explicit bath engineering, thus turning unwanted quantum noises into useful quantum resources. Specifically, we simulate the energy transfer process in a photosynthetic dimer system on IBM-Q cloud. By employing tailored decoherence-inducing gates, we show that quantum dissipative dynamics can be simulated efficiently across coherent-to-incoherent regimes with results comparable to those of the numerically exact classical method. Moreover, we demonstrate a calibration routine that enables consistent and predictive simulations of open-quantum system dynamics in the intermediate coupling regime. This work provides a new direction for quantum advantage in the NISQ era.
Analytical soliton solutions for the beta fractional derivative Gross–Pitaevskii system with linear magnetic and time dependent laser interactions
Authors: Yépez-Martínez H , Inc Mustafa , Alqahtani Rubayyi T 
Published: January 2024

Abstract
The local conformable beta Atangana derivative will be considered for the introduction of the fractional Gross–Pitaevskii model with conformable derivatives of beta type. Analytical expressions for soliton solutions are constructed by sub-equation method with elliptical functions. The main goal of the current research is to determine the general behavior of the soliton solutions, their dependence on the elliptical parameter and the influence of the fractional order parameter on the time and space scales of the solutions. New entire family of solitons were determined by considering the arising constrains over the parameters of the nonlinear fractional Gross–Pitaevskii system. The analytical expressions for the soliton solutions constructed for the fractional order case reduce to the well known solitons previously reported for hyperbolic and periodic tan-type singular solutions for the integer order limit value, when special cases of the Jacobi elliptic functions are considered. Solitons properties are depicted in 3-D level and 2-D illustrations. The fractional solitons here introduced possess some interesting time evolution behavior observed in the 3-D representations, these time properties are not present in the integer order case and has an important dependency on the fractional parameter of the beta derivative. The solitons here introduced for the nonlinear fractional Gross–Pitaevskii equation will be very useful in future works where additional interactions will be introduced for the study of different Bose–Einstein condensation phenomena, the coupled quasi-one dimensional Gross- Pitaevskii equation or other nonlinear phenomena where non regular oscillations will be involved.
The capacitance/conductance and surface state intensity characteristics of the Al/(CMAT)/p-Si structures
Authors: Çetinkaya H G , Bengi S , Sevgili O , Altındal Ş 
Published: January 2024

Abstract
To determine the Al/(CMAT)/p-Si structure’s admittance analysis, capacitance/conductance versus frequency (C/G-V-f) data was obtained in the 3 kHz-3 MHz and −2/4 V ranges at room temperature. The powder form of CeMgAl11O19: Tb (CMAT) was thermally evaporated onto the front of p-Si wafer at 10−6 Torr as interfacial layer. From the Nicollian and Brews method, voltage-dependent spectra of Rs were derived for various frequencies. The parallel conductance and low-high frequency capacitance (CLF-CHF) techniques, respectively, were used to determine the voltage and frequency dependent spectra of Nss and their lifetime (τ). Surface states (Nss), which are identified by admittance measurements, emerge at the M/S interlayer because of high capacitance and conductance values at low frequencies. This can also be explained by the Nss’s ability to track ac signals well at lower frequencies. The normalized parallel conductance versus frequency (Gp/ω-f) plot under various biases shows a peak because of Nss existence. x-ray diffractometer (XRD) was used for structural investigation and the average crystal size (D) of the nanocrystals (CMAT) was found to be less than 0.34 nm by using the Debye-Scherer’s equation.
Mass and tidal parameter extraction from gravitational waves of binary neutron stars mergers using deep learning
Authors: Soma Shriya , Stöcker Horst , Zhou Kai 
Published: January 2024

Abstract
Gravitational Waves (GWs) from coalescing binaries carry crucial information about their component sources, like mass, spin and tidal effects. This implies that the analysis of GW signals from binary neutron star mergers can offer unique opportunities to extract information about the tidal properties of NSs, thereby adding constraints to the NS equation of state. In this work, we use Deep Learning (DL) techniques to overcome the computational challenges confronted in conventional methods of matched-filtering and Bayesian analyses for signal-detection and parameter-estimation. We devise a DL approach to classify GW signals from binary black hole and binary neutron star mergers. We further employ DL to analyze simulated GWs from binary neutron star merger events for parameter estimation, in particular, the regression of mass and tidal deformability of the component objects.
The results presented in this work demonstrate the promising potential of DL techniques in GW analysis, paving the way for further advancement in this rapidly evolving field. The proposed approach is an efficient alternative to explore the wealth of information contained within GW signals of binary neutron star mergers, which can further help constrain the NS EoS.