bluuebunny/crossref_metadata_2025 huggingface dataset:
The magnetic field of a magnetohydrodynamic disk wind: Water maser observations and simulations
Authors: Moscadelli L. , Oliva A. , Surcis G. , Sanna A. , Beltrán M. T. , Kuiper R.
Published: October 2023

Context. Although star-formation models predict that the magnetic field plays an important role in regulating disk-mediated accretion and launching and collimating protostellar jets, observations of the magnetic field close enough (within a few 100 au) to the forming stars are still sparse.

Aims. Our goal is to measure and model the magnetic field distribution in the disk wind of the young stellar object (YSO) IRAS 21078+5211.

Methods. We performed sensitive global very long baseline interferometry observations of the polarized emission of the 22 GHz water masers tracing individual streamlines of the magnetohydrodynamic (MHD) disk wind in IRAS 21078+5211. Our resistive-radiativegravito-MHD simulations of a jet around a forming massive star are able to closely reproduce the observed maser kinematics in the inner jet cavity.

Results. We measure a weak level of 0.3–3.2% of linear and circular polarization in 24 and 8 water masers, respectively. The detected polarized masers sample the direction and the strength of the magnetic field along five distinct streamlines within the inner 100 au region of the disk wind. Along the four streamlines at smaller radii from the jet axis (≤25 au), the sky-projected direction of the magnetic field forms, in most cases, a small offset angle of ≤30º with the tangent to the streamline. Along the stream at larger radii (50–100 au), the magnetic field is sampled at only three separated positions, and it is found to be approximately perpendicular to the streamline tangent at heights of ≈10 and 40 au, and parallel to the tangent at ≈70 au. According to our simulations, the magnetic field lines should coincide with the flow streamlines in the inner jet cavity. The small tilt in the magnetic field direction observed along the inner streams can be well explained by Faraday rotation, assuming a realistic low level of ionization for the molecular shell of the jet of namely ~10−2. The magnetic field amplitudes measured from maser circular polarization are all within a relatively small range of 100–700 mG, which is in good agreement with the simulation results and consistent with reduced magnetic diffusivity in the jet cavity owing to efficient shock ionization.

Conclusions. By comparing observations achieving sub-au linear resolution with source-specific simulations, this work presents a very detailed study of the gas kinematics and magnetic field configuration in the MHD disk wind associated with the YSO IRAS 21078+5211. The close correspondence between flow streamlines and magnetic field lines together with the relatively high strength of the magnetic field indicate that the magnetic field has a dominant role in the launch and collimation of the YSO jet.
Period bouncers as detached magnetic cataclysmic variables
Authors: Schreiber Matthias R. , Belloni Diogo , van Roestel Jan
Published: October 2023

Context. The general prediction that more than half of all cataclysmic variables (CVs) have evolved past the period minimum is in strong disagreement with observational surveys, which show that the relative number of these objects is just a few percent.

Aims. Here, we investigate whether a large number of post-period minimum CVs could detach because of the appearance of a strong white dwarf magnetic field potentially generated by a rotation- and crystallization-driven dynamo.

Methods. We used the MESA code to calculate evolutionary tracks of CVs incorporating the spin evolution and cooling as well as compressional heating of the white dwarf. If the conditions for the dynamo were met, we assumed that the emerging magnetic field of the white dwarf connects to that of the companion star and incorporated the corresponding synchronization torque, which transfers spin angular momentum to the orbit.

Results. We find that for CVs with donor masses exceeding ∼0.04 M⊙, magnetic fields are generated mostly if the white dwarfs start to crystallize before the onset of mass transfer. It is possible that a few white dwarf magnetic fields are generated in the period gap. For the remaining CVs, the conditions for the dynamo to work are met beyond the period minimum, when the accretion rate decreased significantly. Synchronization torques cause these systems to detach for several gigayears even if the magnetic field strength of the white dwarf is just one MG.

Conclusions. If the rotation- and crystallization-driven dynamo – which is currently the only mechanism that can explain several observational facts related to magnetism in CVs and their progenitors – or a similar temperature-dependent mechanism is responsible for the generation of magnetic field in white dwarfs, most CVs that have evolved beyond the period minimum must detach for several gigayears at some point. This reduces the predicted number of semi-detached period bouncers by up to ∼60 − 80%.
Calibration and testing of measurement devices at infrasound frequencies: proof from malfunctioning devices at site
Authors: Rust Marvin , Kling Christoph , Koch Christian , Barham Richard
Published: October 2023

With the growing prevalence of infrasound and potential for annoyance comes the need for noise assessment. Performance validation of measuring instruments is an established necessity for reliable measurement data at conventional frequencies. However, infrasound measurements are critically dependent on the integrity of the microphone. A case study is presented showing that errors in excess of 20 dB result if the microphone diaphragm is perforated, and that such a defect cannot be detected by visual examination or with a typical sound calibrator. A further laboratory study validates the findings, and a scheme is proposed for identifying when such an issue exists.
A strongly conservative hybridizable discontinuous Galerkin method for the coupled time-dependent Navier–Stokes and Darcy problem
Authors: Cesmelioglu Aycil , Lee Jeonghun J. , Rhebergen Sander
Published: October 2023

We present a strongly conservative and pressure-robust hybridizable discontinuous Galerkin method for the coupled time-dependent Navier–Stokes and Darcy problem. We show existence and uniqueness of a solution and present an optimal a priori error analysis for the fully discrete problem when using Backward Euler time stepping. The theoretical results are verified by numerical examples.
The Comparison of Laser Diffraction, PDA and Photogrammetry for Aerosol Measurement
Authors: Huněk Adam , Bartoš Ondřej
Published: October 2023

Optical methods are established as a standard tool for aerosol size measurement. The aim of this paper is to compare the results of two commercial optical instruments based on the phase-Doppler anemometry (PDA) and laser diffraction (LD) with the inhouse optical photogrammetric measurement method. For the purpose of this measurement, a new inhouse image processing procedure was developed with the use of MATLAB script. The accuracy of this method was tested on several calibration particle samples with a sufficient agreement with the PDA and LD commercial instruments. Subsequently, the water droplet distributions of a two-phase nozzle were evaluated by all three methods. The knowledge of the detailed droplet size distribution of the nozzle is then to be used for the development of a new facility for the study of heterogeneous droplet nucleation. Moreover, these results are useful for determining the advantages and disadvantages of these methods for their application in the wider field of aerosol technology.
Traumatic Carotid Artery Dissection — A Case Report
Authors: Berres Taís Otilia , Padua Wagner Lazaretto , Martio Artur Eduardo , Escher Yasmynni , Manzato Luciano Bambini , Vanzin José Ricardo , Karam Octávio Ruschel , Mesquita Filho Paulo Moacir
Published: October 2023

Traumatic carotid artery dissection (TCAD) usually occurs after a direct cervical trauma or blunt trauma that causes hyperextension and excessive rotation of the neck. The most frequent presentation of TCAD is stroke, with 80% of patients developing a stroke in the first week after the trauma. Recent data indicate that symptoms start later in non-survivors (19.5 hours after trauma) compared with survivors (12.5 hours). In this case report, a young boy, 14 years-old, developed TCAD after he fell from his bike. He developed ischemic stroke symptomatology in the eighth day of hospitalization, with full recovery of symtoms after acetylsalicylic acid (AAS) administration. The use of antithrombotic medication is recommended, aiming for better neurological outcomes and prevention of stroke in TCAD patients, as highlighted by our case. However, the treatment recommendations are based on observational studies and expert opinion, owing to the lack of concrete data on the treatment of carotid artery blunt trauma. New studies and data are required to improve diagnosis and treatment of TCAD.
Intraoperative Ultrasonography in Neurosurgery: Experience of an Institution
Authors: Marques Robinson Antonio Menegotto , Marques Adriana Hernandez , Marques Amanda Hernandez
Published: October 2023

Objective Intraoperative ultrasound (IOUS) is an imaging method that can be used in various neurosurgical procedures. It assists in the removal of brain tumors, hematomas, in the insertion of ventricular catheters, and in spinal and peripheral nerve surgeries. The original studies using IOUS were performed with devices that produced lower-quality images, generating little interest in their use. The introduction of ultrasound devices that yielded higher-quality images associated with a relative low cost and ease of use rendered IOUS attractive. Thus, we started using it in multiple neurosurgical procedures, studying its practicality, efficacy and limitations.

Materials and methods A retrospective case study on the use of IOUS in neurosurgery from August 2014 to December 2020 at a single institution, evaluating its practicality, efficacy and limitations.

Results A total of 127 IOUS scans were performed in 112 patients aged 19 to 83 (mean: 53.8) years: 106 scans of the brain, 4 of the spinal cord, and 2 of the peripheral nerves. Brain tumors were the majority, with 86 cases (67.8%). The IOUS was unsatisfactory in 9 cases (7.1%), and there were no cases of infection related to the IOUS.

Conclusion The IOUS is a dynamic, safe, and practical exam. It can be performed in a few minutes and repeated several times during the surgical procedure. It enables surgeons to observe the pulsation of tissues and vessels, the displacement of lumps in liquid collections, and to monitor the drainage of cysts and collections, in vivid, interactive and real-time images.
Declining population and GDP growth
Authors: Lianos Theodore P. , Pseiridis Anastasia , Tsounis Nicholas
Published: October 2023

Businesspeople and politicians seem to be afraid that population reduction will be accompanied by economic recession. In this paper we examine the experience of some countries of various sizes in which population has been declining and observe how GDP, GDP per capita, unemployment rate, and labour force participation rate are evolving during the period that population is declining. Using the pooled mean group (PMG) estimation method, we find that population decline can go hand in hand with growing GDP and increasing per capita GDP, and at the same time the labour participation rate may increase and unemployment may fall.
From the coast to the interior: global economic evolution patterns and mechanisms
Authors: Jin Xiaoming , Luan Weixin , Yang Jun , Yue Wenze , Wan Shulin , Yang Di , Xiao Xiangming , Xue Bing , Dou Yue , Lyu Fangzheng , Wang Shaohua
Published: October 2023

It is well established that nighttime light brightness value, which is measured from satellites, correlates with economic prosperity across the globe. Researchers have diverged over whether economic factors cluster in coastal areas or move to interior areas. By using nighttime light data and applying the random forest algorithm to measure the proportion of global “near regions” GDP, it was seen that global GDP decreased from 67.25% in 2000 to 63.02% in 2018. This research reveals that under the continuous promotion of economic globalization, there is still a spatial imbalance of economic development between global “near regions” and “far regions”; however, economic factors are gradually shifting to interior areas and forming a “coastal remoteness” evolution pattern. Within the intercontinental range, there are obvious differences in the evolution patterns and spatial structure of economic development between the sub-regions. The reduction of overseas transportation costs and diseconomies of scale are the primary reasons for the evolution of “coastal remoteness” in global economic development. Our findings can facilitate future policymaking and the management of global coastal and interior areas, as well as establish new horizons for relevant research topics within the context of land and marine-coordinated development.
The presence of high-energy neutrons in neutron pulses emitted from a kilojoule plasma focus device: Deuterium as a working gas
Authors: Jain Jalaj , Moreno Jose , Loyola Hernan , Davis Sergio , Bora Biswajit , Soto Leopoldo
Published: October 2023

In the present work, a kilo-joule plasma focus device, PF-2kJ, is used as a pulsed neutron generator. Time of flight and neutron spectroscopic measurements suggest neutron energies larger than 5 MeV in the radial and axial directions. The anisotropy in neutron emission suggested a beam-target nuclear fusion mechanism. A simulation tool kit Geant4 is used to interpret and verify the experimentally observed spectroscopic results of neutrons' energies. Based on the findings, it is hypothesized that the pinch and pre-pinch phases invoke suitable conditions for the D–D reaction that produces proton and tritium. The produced tritium nuclei further collide with deuterons in the pinch and post-pinch phases and produce high-energy neutrons. However, the observed high-energy neutrons could be of mixed origin of beam-target nuclear fusion mechanism and D–T fusion reactions.
Discovery of structure–property relations for molecules via hypothesis-driven active learning over the chemical space
Authors: Ghosh Ayana , Kalinin Sergei V. , Ziatdinov Maxim A.
Published: October 2023

The discovery of the molecular candidates for application in drug targets, biomolecular systems, catalysts, photovoltaics, organic electronics, and batteries necessitates the development of machine learning algorithms capable of rapid exploration of chemical spaces targeting the desired functionalities. Here, we introduce a novel approach for active learning over the chemical spaces based on hypothesis learning. We construct the hypotheses on the possible relationships between structures and functionalities of interest based on a small subset of data followed by introducing them as (probabilistic) mean functions for the Gaussian process. This approach combines the elements from the symbolic regression methods, such as SISSO and active learning, into a single framework. The primary focus of constructing this framework is to approximate physical laws in an active learning regime toward a more robust predictive performance, as traditional evaluation on hold-out sets in machine learning does not account for out-of-distribution effects which may lead to a complete failure on unseen chemical space. Here, we demonstrate it for the QM9 dataset, but it can be applied more broadly to datasets from both domains of molecular and solid-state materials sciences.
Describing the analog resistance change of HfOx-based neuromorphic synapses using a compact series trap-assisted tunneling and Ohmic conduction model
Authors: Athena Fabia F. , Vogel Eric M.
Published: October 2023

Changes in the resistance of Ti/HfOx synapses are known to be governed by a thin-oxide barrier associated with the oxidation/reduction of a Hf-rich conducting filament (CF). However, experimental characterization of the CF is challenging. Critical physical properties and processes, such as the barrier location, time-dependent thickness during analog pulsing, and the temperature-effect on current, need to be better established. In this work, a compact model based on Trap-Assisted-Tunneling and Ohmic transport is utilized to analyze the analog switching of HfOx synapses. The model agrees well with the experimentally observed current–voltage relation and its temperature dependence. The extracted barrier heights during analog pulsing are consistent with a barrier situated near the reset anode; the electrode is opposite to the Ti oxygen-reservoir layer. A Finite Element Analysis simulation, which incorporates oxygen-vacancy migration, independently supports this conclusion. The model further permits extraction of the barrier thickness in relation to the analog pulses.
Critical and controversial issues pertaining to the growth and properties of Cu2O in the context of energy conversion
Authors: Prountzou Eleni , Ioannou Andreas , Sapalidis Dimitrios , Pavlidou Eleni , Katsikini Maria , Othonos Andreas , Zervos Matthew
Published: October 2023

Cu2O has been deposited on m-, r-, and a-Al2O3 by reactive sputtering of Cu using Ar with different contents of O2 followed by annealing under carefully optimized conditions at 500 °C under Ar:H2 in order to prevent the oxidation and reduction of the Cu2O layers, which have a cubic crystal structure and are bulk-relaxed. We find that the content of O2 influences the structural and optical properties of the Cu2O layers that exhibited a detailed spectral structure and distinct peaks at 2.75, 2.54, and 2.17 eV corresponding to the indigo, blue, and yellow direct gap transitions of Cu2O as observed by ultrafast pump–probe spectroscopy at room temperature. However, we also observed a transition at 1.8 eV that is related to the occurrence of states ∼0.4 eV below the conduction band minimum of Cu2O. We discuss the controversial origin of these states, which are usually attributed to donor-like oxygen vacancy states, and suggest that the origin of these states may be related to traps at the interfaces of CuO/Cu2O nanostructures, which is important in the context of energy conversion pertaining to solar cells and photocatalysis.
Smooth particle mesh Ewald-integrated stochastic Lanczos many-body dispersion algorithm
Authors: Poier Pier Paolo , Lagardère Louis , Piquemal Jean-Philip
Published: October 2023

We derive and implement an alternative formulation of the Stochastic Lanczos algorithm to be employed in connection with the Many-Body Dispersion model (MBD). Indeed, this formulation, which is only possible due to the Stochastic Lanczos’ reliance on matrix-vector products, introduces generalized dipoles and fields. These key quantities allow for a state-of-the-art treatment of periodic boundary conditions via the O(Nlog(N)) Smooth Particle Mesh Ewald (SPME) approach which uses efficient fast Fourier transforms. This SPME-Lanczos algorithm drastically outperforms the standard replica method which is affected by a slow and conditionally convergence rate that limits an efficient and reliable inclusion of long-range periodic boundary conditions interactions in many-body dispersion modelling. The proposed algorithm inherits the embarrassingly parallelism of the original Stochastic Lanczos scheme, thus opening up for a fully converged and efficient periodic boundary conditions treatment of MBD approaches.
Flow and acoustic fields investigation of noise reduction by micro vortex generators in supersonic nozzles
Authors: Saleem M. , Karnam A. , Rodriguez O. , Liu J. , Gutmark E.
Published: October 2023

The role of micro-vortex generators (MVGs) in supersonic jet noise reduction is investigated. Studies are performed to understand the noise reduction mechanisms of these devices. MVGs are implemented on a scale model representative of GE-F404 nozzles. Configurations consisting of single and dual arrays of MVGs were tested for pressure ratios relevant to takeoff operating conditions. A combination of laboratory measurements and large-eddy simulations are used. Particle image velocimetry reveals that MVGs placed inside the nozzle form oblique shocks that interact with the jet plume's shock cell structure and greatly modify the shock-cell structure issued from the nozzle throat. This modification can weaken the jet plume shock-cell structure and even reduce the jet core velocities. Convective velocities estimated from the high-speed Schlieren imaging showed a significant reduction in magnitude caused by MVGs. When compared to the baseline design, the MVG nozzles showed noise reduction up to 10 dB in the upstream direction and near 5 dB in the peak downstream radiation angle at cold jet conditions. Near-field acoustic measurements showed a significant reduction of low-frequency turbulent mixing noise. Scaling analysis showed that MVGs are capable of delivering the same noise reduction performance across different model scales.
The murine retinal pigment epithelium requires peroxisomal β-oxidation to maintain lysosomal function and prevent dedifferentiation
Authors: Kocherlakota Sai , Das Yannick , Swinkels Daniëlle , Vanmunster Maarten , Callens Manon , Vinckier Stefan , Vaz Frédéric M. , Sinha Debasish , Van Veldhoven Paul P. , Fransen Marc , Baes Myriam
Published: October 2023

Retinal pigment epithelium (RPE) cells have to phagocytose shed photoreceptor outer segments (POS) on a daily basis over the lifetime of an organism, but the mechanisms involved in the digestion and recycling of POS lipids are poorly understood. Although it was frequently assumed that peroxisomes may play an essential role, this was never investigated. Here, we show that global as well as RPE-selective loss of peroxisomal β-oxidation in multifunctional protein 2 (MFP2) knockout mice impairs the digestive function of lysosomes in the RPE at a very early age, followed by RPE degeneration. This was accompanied by prolonged mammalian target of rapamycin activation, lipid deregulation, and mitochondrial structural anomalies without, however, causing oxidative stress or energy shortage. The RPE degeneration caused secondary photoreceptor death. Notably, the deterioration of the RPE did not occur in an
Mfp2/rd1
mutant mouse line, characterized by absent POS shedding. Our findings prove that peroxisomal β-oxidation in the RPE is essential for handling the polyunsaturated fatty acids present in ingested POS and shed light on retinopathy in patients with peroxisomal disorders. Our data also have implications for gene therapy development as they highlight the importance of targeting the RPE in addition to the photoreceptor cells.
Cognate facilitation in single- and dual-language contexts in bilingual children’s word processing
Authors: Koutamanis Elly , Kootstra Gerrit Jan , Dijkstra Ton , Unsworth Sharon
Published: October 2023

We examined the extent to which cognate facilitation effects occurred in simultaneous bilingual children’s
production and comprehension and how these were modulated by language dominance and language context. Bilingual Dutch-German
children, ranging from Dutch-dominant to German-dominant, performed picture naming and auditory lexical decision tasks in
single-language and dual-language contexts. Language context was manipulated with respect to the language of communication (with
the experimenter and in instructional videos) and by means of proficiency tasks. Cognate facilitation effects emerged in both
production and comprehension and interacted with both dominance and context. In a single-language context, stronger cognate
facilitation effects were found for picture naming in children’s less dominant language, in line with previous studies on
individual differences in lexical activation. In the dual-language context, this pattern was reversed, suggesting inhibition of
the dominant language at the decision level. Similar effects were observed in lexical decision. These findings provide evidence
for an integrated bilingual lexicon in simultaneous bilingual children and shed more light on the complex interplay between
lexicon-internal and lexicon-external factors modulating the extent of lexical cross-linguistic influence more generally.
On the constitutional relevance of non‑discursive enlanguaged doings to sociomaterial practices
Authors: Gahrn-Andersen Rasmus
Published: October 2023

In expanding on the ‘dynamics first, symbols afterwards’ principle (Cowley
2009) of Distributed Language research, I propose that embodied linguistic competencies comprise the prerequisite for
human agents to engage in sociomaterial practices. I make the case that human practical activity is fundamentally ‘enlanguaged’
and that linguistic skills are not only trans-practical in the sense of enabling agents to engage in diverse activities across
practices but also that they constitute the basis for adult skill acquisition (see Dreyfus and
Dreyfus 1986) more generally. Specifically, I explore language-relative skills as the enablers of more diverse
activities than what is prescribed to them by Saussurean linguistic tradition i.e., the denotative relations intrinsic to
linguistic signs as well the rule-governed combinations of such signs into meaningful sentences.
How micron-sized exocrine vesicles release content: A comparison with sub-micron endocrine vesicles
Authors: Wei Lisi , Wang Xin , Wu Ling-Gang
Published: October 2023

Exocytosis releases vesicular contents to mediate physiological functions. In this issue, Biton et al. (https://doi.org/10.1083/jcb.202302112) found four modes of releasing micron-sized exocrine vesicles and the underlying mechanisms involving actomyosin and BAR domain proteins. We highlight their discovery, compare it with much smaller/faster neuroendocrine vesicle fusion, and draw distinct and conserved principles regarding their membrane transformations, pore dynamics, and underlying mechanisms.
On the problem of the classical limit for statistical characteristics of a quantum Coulomb plasma
Authors: Trigger S A
Published: October 2023

The general structure of the perturbation theory series for the thermodynamic potential of a system of electrons and point ions is discussed. In the classical limit, when Planck’s constant ℏ → 0, the particular terms of the perturbation theory series diverge due to the impossibility of maintaining of stability of a purely classical system of the opposite sign charges attracted to each other. At the same time, it is known that in a certain range of parameters, a thermodynamic potential that does not contain Planck’s constant is a good approximation. Such thermodynamic functions describes the experimental data well and corresponds to the molecular dynamics calculations of model quasi-Coulomb systems. It is shown that the transition to a purely classical description, which implies the limit ℏ → 0, is impossible, but the terms of the series containing ℏ are small for certain plasma parameters and can be discarded. This is the rationale explanation of using classical models and approximations to describe plasma in certain parameter ranges. On this basis, a hypothesis is formulated about the absence of a classical limit for all measurable physical properties (including kinetic characteristics) of the Coulomb model of plasma, in which point particles interact according to the Coulomb law and, therefore, there are no adjustable parameters.
Consensus analysis of chain star networks coupled by leaf nodes
Authors: Chen Jing , Zhou Ling , Sun Weigang
Published: October 2023

Coupled star networks coupled by hub nodes have attracted significant interest due to the interplay between their coupling forms and dynamics. This paper introduces a novel family of chain star networks that are connected via a small number of leaf nodes. The coherence of these star networks is quantified using the Laplacian spectrum. By leveraging the network structures, we calculate the characteristic polynomial of the Laplacian matrix and obtain an exact solution for network coherence in relation to network parameters. In addition, we explore the robustness of network coherence against variations in network parameters. Furthermore, we compare the coherence performance of coupled star networks across different coupling forms Our findings demonstrate that the networks coupled by leaf nodes exhibit better coherence.
Analytical solution of local fractal continuum traffic flow model
Authors: Pokhriyal Bhawna , Goswami Pranay , Kumar Kranti
Published: October 2023

This study developed a continuum traffic flow model with local fractional derivatives. This model overcomes the non-differentiable traffic parameters arising in vehicular traffic flow. The proposed model is solved using the local fractional Laplace variational iteration method (LFLVIM) and is well suited for analyzing the dynamical evolution of non-differentiable traffic density and speed function. Furthermore, the stability of the solution for the continuum model has also been discussed. Illustrative examples are also discussed to show the effectiveness of employing LFLVIM in the suggested model. Additionally, numerical simulations for each instance have been displayed. This research indicates that the utilized iterative approach is efficient and may be used to derive the non-differentiable solution to the proposed continuum traffic model.
A four-tensor momenta equation for rolling physics
Authors: Güémez J , Mier J A
Published: October 2023

Relativistic four-tensor equation dJ

μ
ν
= M

μ
ν
dt is developed to analyse linear translation with rotation processes. The postulated cause-effect four-tensor equation, a relativistic generalisation for classical angular-impulse–angular-momentum variation equation dJ = Mdt, includes the Poinsot-Euler rotation (angular-impulse–angular-momentum variation) equation, Newton’s second law (linear-impulse–linear-momentum variation equation), and thermodynamics first law (work–energy equation). This four-tensor formalism is applied to describe three linear translation with rotation processes: a ring rolling on the floor by a horizontal force linear impulse and torque, fulfilling the rolling condition (mechanical energy conservation), a spinning ring placed on the ground until achieved the rolling condition (mechanical energy dissipation by friction), and a fireworks wheel ascending an incline (mechanical energy production by decreasing a thermodynamic potential).
Conservation laws, bound-state solitons and modulation instability for a variable-coefficient higher-order nonlinear Schrödinger equation in an optical fiber
Authors: Yang Sheng-Xiong , Wang Yu-Feng , Jia Rui-Rui
Published: October 2023

Under investigation in this paper is a variable-coefficient sixth-order nonlinear Schrödinger equation, which describes the propagation of attosecond pulses in an optical fiber. Based on Lax pair, infinitely-many conservation laws are constructed. With the aid of auxiliary functions, bilinear forms are derived. In addition, the one- and two-soliton solutions are obtained via the Hirota method. The influences of variable coefficients for soliton velocity and profile are discussed. Particularly, the interaction periods and soliton separation factor of bound-state solitons are analyzed. Finally, modulation instability is investigated. The reported results could be used to understand related soliton molecule and optical instability phenomena in nonlinear optics.
Conservation laws, Lie symmetries, self adjointness, and soliton solutions for the Selkov–Schnakenberg system
Authors: Ali Kashif , Seadawy Aly R , Rizvi Syed T R , Aziz Noor
Published: October 2023

In this article, we explore the famous Selkov–Schnakenberg (SS) system of coupled nonlinear partial differential equations (PDEs) for Lie symmetry analysis, self-adjointness, and conservation laws. Moreover, miscellaneous soliton solutions like dark, bright, periodic, rational, Jacobian elliptic function, Weierstrass elliptic function, and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential equations. All these results are displayed graphically by 3D, 2D, and contour plots.
Properties of focused Laguerre–Gaussian beam propagating in anisotropic ocean turbulence
Authors: Wang 王 Xinguang 新光 , Ma 马 Yangbin 洋斌 , Yuan 袁 Qiujie 邱杰 , Chen 陈 Wei 伟 , Wang 王 Le 乐 , Zhao 赵 Shengmei 生妹
Published: October 2023

We analyze the properties of a focused Laguerre–Gaussian (LG) beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel principle. Under the Rytov approximation theory, we derive the analytical formula of the channel capacity of the focused LG beam in the anisotropic ocean turbulence, and analyze the relationship between the capacity and the light source parameters as well as the turbulent ocean parameters. It is found that the focusing mirror can greatly enhance the channel capacity of the system at the geometric focal plane in oceanic turbulence. The results also demonstrate that the communication link can obtain high channel capacity by adopting longer beam wavelength, greater initial beam waist radius, and larger number of transmission channels. Further, the capacity of the system increases with the decrease of the mean squared temperature dissipation rate, temperature-salinity contribution ratio and turbulence outer scale factor, and with the increase of the kinetic energy dissipation rate per unit mass of fluid, turbulence inner scale factor and anisotropy factor. Compared to a Hankel–Bessel beam with diffraction-free characteristics and unfocused LG beam, the focused LG beam shows superior anti-turbulence interference properties, which provide a theoretical reference for research and development of underwater optical communication links using focused LG beams.
Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf: TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS
Authors: Wang Jia-Qi , Jiang Xiao-Jun , Zheng Jie , Kellermann Hanna , Riffeser Arno , Wang Liang , Collins Karen A. , Bieryla Allyson , Buchhave Lars A. , Howell Steve B. , Furlan Elise , Girardin Eric , Gregorio Joao , Jensen Eric , Murgas Felipe , Yilmaz Mesut , Quinn Sam , Gao Xing , Zhou Ruo-Yu , Grupp Frank , Wang Hui-Juan
Published: October 2023

We report the confirmation of a sub-Saturn-size exoplanet, TOI-1194 b, with a mass of about

0.456

−
0.051

+
0.055

M
J, and a very low mass companion star with a mass of about 96.5 ± 1.5 M
J, TOI-1251 B. Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite (TESS) are suitable for further follow-up observations by ground-based telescopes with small and medium apertures. The analysis is performed based on data from several telescopes worldwide, including telescopes in the Sino-German multiband photometric campaign, which aimed at confirming TESS Objects of Interest (TOIs) using ground-based small-aperture and medium-aperture telescopes, especially for long-period targets. TOI-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric data. We measure an orbital period of 2.310644 ± 0.000001 days, the radius is

0.767

−
0.041

+
0.045

R
J and the amplitude of the RV curve is

69.4

−
7.3

+
7.9

m s−1. TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data, whose orbital period is

5.963054

−
0.000001

+
0.000002

days, radius is

0.947

−
0.033

+
0.035

R
J and amplitude of the RV curve is

9849

−
40

+
42

m s−1.
Relations between the Fractional Variation of the Ionizing Continuum and C iv Broad Absorption Lines with Different Ionization Levels
Authors: Lin Ying-Ru , Pan Cai-Juan , Lu Wei-Jian
Published: October 2023

This paper explores the correlation between the fractional variation of the ionizing continuum and C iv broad absorption lines (BALs) with different ionization levels. Our results reveal anti-correlations between fractional variation of the continuum and fractional equivalency width (EW) variation of the C iv BALs without Al iii BAL/mini-BALs at corresponding velocities, providing evidence for the widespread influence of the ionizing continuum variability on the variation of HiBALs. Conversely, for C iv BALs accompanied by Al iii BAL/mini-BALs (LoBAL groups), no significant correction is detected. The absence of such a correlation does not rule out the possibility that variations in these low-ionization lines are caused by ionizing continuum variability, but rather suggests the influence of BAL saturation to some extent. This saturation effect is reflected in the distribution of the fractional EW variation, where the C iv BAL group accompanied by Al iii BAL has a smaller standard deviation for the best-fitting Gaussian component than the two BAL groups without Al iii BAL. However, the distribution of fractional variation of their continuum does not show any significant difference. Besides the saturation influence, another potential explanation for the lack of correlations in the LoBAL groups may be the effects of other variability mechanisms besides the ionization change, such as clouds transiting across the line of sight.
Quantitative Analysis of Seeing with Height and Time at Muztagh-Ata Site Based on ERA5 Database
Authors: Wu Xiao-Qi , Xiao Cun-Ying , Esamdin Ali , Xu Jing , Wang Ze-Wei , Xiao Luo
Published: October 2023

Seeing is an important index to evaluate the quality of an astronomical site. To estimate seeing at the Muztagh-Ata site with height and time quantitatively, the European Centre for Medium-Range Weather Forecasts reanalysis database (ERA5) is used. Seeing calculated from ERA5 is compared consistently with the Differential Image Motion Monitor seeing at the height of 12 m. Results show that seeing decays exponentially with height at the Muztagh-Ata site. Seeing decays the fastest in fall in 2021 and most slowly with height in summer. The seeing condition is better in fall than in summer. The median value of seeing at 12 m is 0.89 arcsec, the maximum value is 1.21 arcsec in August and the minimum is 0.66 arcsec in October. The median value of seeing at 12 m is 0.72 arcsec in the nighttime and 1.08 arcsec in the daytime. Seeing is a combination of annual and about biannual variations with the same phase as temperature and wind speed indicating that seeing variation with time is influenced by temperature and wind speed. The Richardson number Ri is used to analyze the atmospheric stability and the variations of seeing are consistent with Ri between layers. These quantitative results can provide an important reference for a telescopic observation strategy.
Monitoring of the offset between UTC and its prediction broadcast by the GNSS
Authors: Defraigne P , Pinat E , Petit G , Meynadier F
Published: October 2023

We present a new approach to report, in the section 4 of International Bureau of Weights and Measures Circular T, daily values of the offset between Coordinated Universal Time (UTC) and the predictions of UTC broadcast by the Global Navigation Satellite Systems (GNSS), this quantity we name bUTCGNSS. In this approach, the determination of UTC-bUTCGNSS is based on data collected by several multi-GNSS stations in selected time laboratories worldwide. Test computations over a 7-month period from July 2022 to January 2023 show that the offset between UTC and bUTCGNSS was between 30 and 50 ns for GLONASS, between 5 and 20 ns for BeiDou, and between −5 and +5 ns for GPS and Galileo. We derive the uncertainty on the reported values, which is 4.1 ns for BeiDou and GPS, 3.7 ns for Galileo and 6.6 ns for GLONASS and show that, over the test period, the reported values of UTC-bUTCGNSS and the solutions obtained from each multi-GNSS station are all consistent within the 1-sigma uncertainties.
Distally-referred surface electrical nerve stimulation (DR-SENS) for haptic feedback
Authors: Mesias Luis , Gormez M Akif , Tyler Dustin J , Makowski Nathaniel S , Graczyk Emily L , Fu Michael J
Published: October 2023

Objective. This study’s objective is to understand distally-referred surface electrical nerve stimulation (DR-SENS) and evaluates the effects of electrode placement, polarity, and stimulation intensity on the location of elicited sensations in non-disabled individuals. Approach. A two-phased human experiment was used to characterize DR-SENS. In Experiment One, we explored 182 electrode combinations to identify a subset of electrode position combinations that would be most likely to elicit distally-referred sensations isolated to the index finger without discomfort. In Experiment Two, we further examined this subset of electrode combinations to determine the effect of stimulation intensity and electrode position on perceived sensation location. Stimulation thresholds were evaluated using parameter estimation by sequential testing and sensation locations were characterized using psychometric intensity tests. Main Results. We found that electrode positions distal to the wrist can consistently evoke distally referred sensations with no significant polarity dependency. The finger-palm combination had the most occurrences of distal sensations, and the different variations of this combination did not have a significant effect on sensation location. Increasing stimulation intensity significantly expanded the area of the sensation, moved the most distal sensation distally, and moved the vertical centroid proximally. Also, a large anodic-leading electrode at the elbow mitigated all sensation at the anodic-leading electrode site while using symmetric stimulation waveforms. Furthermore, this study showed that the most intense sensation for a given percept can be distally referred. Lastly, for each participant, at least one of the finger-palm combinations evaluated in this study worked at both perception threshold and maximum comfortable stimulation intensities. Significance. These findings show that a non-invasive surface electrical stimulation charge modulated haptic interface can be used to elicit distally-referred sensations on non-disabled users. Furthermore, these results inform the design of novel haptic interfaces and other applications of surface electrical stimulation based haptic feedback on electrodes positioned distally from the wrist.
Crystallographic Study of Grain Refinement in Ni Alloys with Ni-RE Intermetallics
Authors: Zhong Zengyi , Wu Xianggang , Zha Dong , Zhang Xumin , Luo Lan
Published: October 2023

Rare earth-doped nickel (Ni-RE) alloys are very attractive for the neutron shielding application for excellent neutron absorption and good mechanical behavior. Ni-RE intermetallics are important for their precipitation reinforcement in Ni alloys. In this work, Ni-RE intermetallics have been founded to be Ni grain refiners, which has been proved both by nucleation crystallography analysis and experiments. Ni-RE intermetallics could work as heterogeneous nucleation well, either different in atomic structures (for example, Ni17RE2, Ni5RE, Ni7RE2, Ni3RE, Ni2RE having matching orientation relationships as (111)Ni // (0004)Ni17Gd2 with

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, (111)Ni // (0002)Ni5Gd with

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, (111)Ni // (00018)Ni7Gd2 with

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, (111)Ni // (00012)Ni3Gd with

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, (111)Ni // (222)Ni2Gd with

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) or different in rare earth element (for example, (111)Ni // (0002)Ni5RE with

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is general matching orientation relationships (ORs) of Ni5RE (RE = Sc, Y, La ~ Lu) for Ni grains). When RE dopant mass fraction is 1 wt%, the grain size is reduced from ~50 μm to 15 μm, and the refinement effect reaches the best. The work proposes Ni-RE intermetallics as good heterogeneous nuclei for Ni grains with an atomic level understanding and provides theoretical guidance for high-strength nickel alloy design.
Denoising Method of Hydro-turbine Vibration Signal Based on Joint WOA-VMD and Improved Wavelet Threshold
Authors: Bi Lei , Yu Xiao , Jiang Dongrong , Peng Hailong , Hu Feng , Shi Keke , Liang Ke , Ye Xu
Published: October 2023

Comparing to the untreated signal, the traditional wavelet thresholding functions decomposed and reconstructed signal has a constant error. Variational mode decomposition (VMD) sets different penalty factor α and mode decomposition layer K during signal processing will lead to the final noise reduction results. Therefore, this paper introduces the Whale Optimization Algorithm (WOA)-VMD and improved wavelet threshold denoising for oscillation signal disposal of hydraulic turbine. Firstly, WOA was used to optimize the VMD decomposition parameters α and K with the local minimum of envelope entropy as the objective function, and the optimal noise reduction effect was obtained. Secondly, the vibration signals with noise were deconstructed into K intrinsic mode functions (IMF) after VMD, and their thresholds were set. Furthermore, the IMF component below the threshold value is denoised again by improving the wavelet threshold value. Finally, the IMF reorganization after de-noising is used to obtain the final noise reduction signal. Through the verification analysis, the combination of WOA-VMD and improved wavelet threshold function denoising method could effectively filter the noise in the signal and significantly improve the noise reduction effect of the hydraulic turbine vibration signal.
Study on Chloride Diffusion Behaviors of Recycled Concrete of Random Aggregates
Authors: Yao Zeliang , Zhang Yang , Linghu Tianjing , Qi Yalun , Lang Maosen , Dang Faning
Published: October 2023

Based on the chloride ions (Cl−) diffusion model and aggregate grading theory, PYTHON and COMSOL are used to construct a mesoscopic model of recycled concrete random polygon aggregate and verify its validity in combination with existing experimental results. The diffusion law of Cl− in recycled concrete and the law of influence of critical factors on the Cl− erosion resistance are studied by calculating and analyzing the Cl− erosion resistance of recycled concrete under different working conditions such as the diffusivity of new and old mortar, the thickness of old mortar and the replacement ratio of recycled aggregate. The results show that the simulation results agree well with the test results, and the method can better reproduce the Cl− diffusion process inside the recycled concrete. There are discontinuous features based on the relationship curves between the Cl− concentration and the depth of the recycled concrete. The Cl− concentration inside the concrete gradually increases with the increase of the diffusion rate of the old and new mortars. The resistance behavior of the recycled concrete to Cl− attack decreases with the increase of the thickness of the old mortar.
Regional Ionospheric Frequency Domain Characterization and Short-term Forecasting Methods
Authors: Kang Lihua , Wang Shuai , Cong Dianwei , Yin Yunxia , Li Lifeng
Published: October 2023

Total electron content (TEC) is an important characteristic parameter of the ionosphere, which has a great impact on applications such as navigation error correction. The paper addresses the need for short- and medium-term forecasting of regional ionospheric TEC. Firstly, we analyze the frequency domain characteristics of ionospheric TEC, and analyze the data in the frequency domain based on the characteristics of trend, periodicity and abruptness of ionospheric TEC changes influenced by solar activity, combined with the Prophet algorithm. Then, according to its frequency domain characteristics, Prophet is used to achieve hour-by-hour prediction. The computer modeling results show that the RMSE of the 7-day forecast is better than 1.262 TECU during the geomagnetically quiet period, and the method is suitable for the short- and medium-term forecasting of ionospheric TEC with good forecast accuracy and time efficiency.