Article
Multidisciplinary Sciences
Sha Li, Yaguo Tang, Lisa Ortmann, Bradford K. Talbert, Cosmin I. Blaga, Yu Hang Lai, Zhou Wang, Yang Cheng, Fengyuan Yang, Alexandra S. Landsman, Pierre Agostini, Louis F. DiMauro
Summary: Studies have been mostly theoretical on laser-driven strong field processes under a (quasi-)static field, but this study provides experimental evidence by using a bichromatic approach for high harmonic generation (HHG) in a dielectric. The authors investigate the physics behind the THz field induced static symmetry breaking and its effects on even-/odd-order harmonics, and demonstrate the modulation of harmonic distribution as a way to probe HHG dynamics. They also report a delay-dependent frequency shift in even-order harmonics, suggesting limitations in the static symmetry breaking interpretation and opening opportunities in precise attosecond pulse shaping.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Chemical
Lu Wang, Jiayi Kang, Chenglong Zhu, Zhongxiang Zhou, Shaojin Wang, Zhi Huang
Summary: This study explores the use of an angle-adjustable rotating device to improve the radio frequency (RF) heating uniformity of packaged food powder. The researchers established a mathematical model and conducted experiments to predict the effects of different rotation directions, speeds, and package dimensions on the temperature uniformity of red pepper powder (RPP). The results showed that the best heating uniformity of RPP could be achieved with an inclined angle of 20 degrees and a rotation speed of 4 rad min(-1). The laboratory-scale rotating device could lay a substantial foundation for its large-scale applications in RF systems and make food products more controllable.
JOURNAL OF FOOD ENGINEERING
(2023)
Article
Astronomy & Astrophysics
Thomas Madler, Emanuel Gallo
Summary: Using a quasispherical approximation and affine-null coordinates, this paper presents high order approximations of the metric functions for a slowly rotating stationary and axisymmetric vacuum spacetime. It verifies the equivalence of the metric with the Kerr metric in the slowly rotating approximation and shows that the additional integration constants can be absorbed into the overall Komar mass and Komar angular momentum of a slowly rotating black hole.
Article
Neurosciences
Muthumeenakshi Subramanian, Chia-Chu Chiang, Nicholas H. Couturier, Dominique M. Durand
Summary: The study demonstrates that electric field coupling can propagate various types of neural signals, including interictal spikes, theta waves, and seizures, through a volume conductor in vivo. The propagation speed is not affected by transection, and the amplitude and duration of the signals influence the probability of propagation.
EXPERIMENTAL NEUROLOGY
(2022)
Article
Physics, Particles & Fields
Muhammad Zahid, Javlon Rayimbaev, Furkat Sarikulov, Saeed Ullah Khan, Jingli Ren
Summary: Testing gravity theories using astrophysical observations is an important and interesting issue in relativistic astrophysics. Recent research has analyzed the shadow of supermassive black holes located at the center of the Milky Way and Meissner 87 galaxies, obtained from the Event Horizon Telescope collaboration, to provide insights into the spacetime around these black holes.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Multidisciplinary Sciences
Aleksandr Y. Ukhorskiy, Kareem A. Sorathia, Viacheslav G. Merkin, Chris Crabtree, Alex C. Fletcher, David M. Malaspina, Steven J. Schwartz
Summary: This paper investigates plasma convection in the Earth's magnetosphere and its connection to various kinetic processes. The study shows that mesoscale dipolarization flows generate suprathermal electron instabilities, leading to the observed kinetic waves and structures. These findings provide valuable insights into the dynamics of magnetospheric plasma and wave activities.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Electrical & Electronic
Young-Pyo Hong, Jeong-Il Park, Tae-Weon Kang, Joo-Gwang Lee, No-Weon Kang
Summary: This article presents a standard field generation system with an antenna for calibrating a Ka-band electric-field probe. By measuring system parameters and minimizing variations in probe orientation and separation distance, the overall uncertainty is reduced. The system is expected to generate a standard field higher than 10 V/m in the frequency range of 26.5-40 GHz, with an expanded uncertainty of 5.1-5.3% at different frequencies.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Physics, Fluids & Plasmas
Christopher L. Sercel, Tate M. Gill, Benjamin A. Jorns
Summary: The induced magnetic field during acceleration in a pulsed rotating magnetic field (RMF) thruster is experimentally investigated. The plasma currents induced in the thruster are shown to be able to form a field-reversed configuration plasmoid, and the Lorentz force resulting from the induced magnetic field contributes to about 25% of the measured thrust.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Mathematics, Applied
Jiaqi Yang
Summary: The study focuses on an incompressible and inviscid conducting fluid with surface tension and vertical electric field. Local-in-time estimates on the interface in H-3k(+1) and the velocity fields in H-3k were obtained using the reduced equations and a method introduced by Shatah and Zeng. Estimates of a vertical electric field were also derived from the estimates of the interface and elliptic estimates.
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS
(2021)
Article
Multidisciplinary Sciences
Wei Wang, John E. Vidale
Summary: The differential rotation of Earth's inner core relative to the mantle was investigated using precisely located nuclear explosions. It was found that the inner core displayed both subrotation and superrotation, contradicting current rotation models. These observations support a model of oscillation between the inner core and mantle, indicating a balance between them.
Article
Astronomy & Astrophysics
Matteo Buzzegoli, Jonathan D. Kroth, Kirill Tuchin, Nandagopal Vijayakumar
Summary: In this study, we investigated the synchrotron radiation emitted by a charged fermion in a constant magnetic field parallel to the axis of rotation. The rotation is classical and independent of the magnetic field. We derived the intensity, spectrum, and chirality of the electromagnetic radiation using the exact solution of the Dirac equation. Our numerical calculations demonstrate that the effect of rotation on the radiation intensity increases with the particle energy and can either strongly enhance or suppress the radiation, depending on the relative orientation of the vectors omega and B and the sign of the electric charge.
Article
Chemistry, Physical
Roni Kroll, Yoav Tsori
Summary: We propose a model that describes ion-induced nucleation in fluids, which can be induced by various charged particles such as molecular aggregates, large ions, colloids, or aerosol particles. This model extends the Thomson model to polar environments and solves the Poisson-Boltzmann equation to determine the potential profiles and energy around the charged core. Our results are analytical under the Debye-Huckel limit and numerical otherwise. By analyzing the Gibbs free energy curve, we identify the metastable and stable states, as well as the energy barrier between them, under different saturation values, core charges, and salt concentrations. Additionally, we calculate the phase lines in the phase diagram of supersaturation and core charge, revealing different regions of electro-prewetting, spontaneous nucleation, ion-induced nucleation, and classical-like nucleation.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Kosuke Yasuji, Tomo Sakanoue, Fumihiro Yonekawa, Katsuichi Kanemoto
Summary: The recombination between electrons and holes in electroluminescence processes has never been directly evaluated. In this study, the operation dynamics of light-emitting electrochemical cells were visualized with spectroscopic techniques, leading to a rapid device evaluation.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Environmental
Yong Han, Shuren Ma, Jun Ma, Pascal Guiraud, Xiaoqiang Guo, Yingjie Zhang, Tifeng Jiao
Summary: In this study, molecular dynamics simulations were used to investigate the effect of an electric field on the adsorption characteristics of APAP on GO under alkaline conditions. The results showed that the external electric field weakened the interaction between GO and APAP, and altered the hydrophobicity on both sides of GO.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Geosciences, Multidisciplinary
D. P. Hartley, I. W. Christopher, C. A. Kletzing, W. S. Kurth, O. Santolik, I. Kolmasova, M. R. Argall, N. Ahmadi
Summary: A new sheath impedance model is developed to explain the effect of variable coupling impedance between Van Allen Probes instruments and ambient plasma on electric field wave measurements. The study quantifies the impact of this sheath correction on measured chorus wave properties and finds that the sheath-corrected electric field wave power is typically 2 to 9 times larger than the uncorrected measurement. The sheath correction also affects the Poynting vector, increasing the Poynting flux by a factor of 2 and changing the propagation direction in 2% of cases.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Engineering, Multidisciplinary
Ying Xie, Ping Zhou, Jun Ma
Summary: This paper investigates the problem of information exchange and signal encoding between neural circuits. The results show that adaptive synchronization between different neural circuits can be achieved through coupling, and energy diversity plays an important role in controlling synchronization.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Mathematics, Interdisciplinary Applications
Zhigang Zhu, Xiaofeng Zhang, Yisen Wang, Jun Ma
Summary: This paper investigates the adaptation and filtering capability of a sound-sensitive neural circuit using a FitzHugh-Nagumo based autaptic neuron. The results show that the excitatory chemical autapse can act as a narrow-band filter, while the inhibitory chemical autapse enables the neuron to converge its amplitude and exhibits bursting adaptation. Additionally, the electrical autaptic neuron's response can be modulated by both time-delay feedback gains.
INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS
(2023)
Article
Computer Science, Artificial Intelligence
Dong Liu, Yong Wang, Chenhong Luo, Jun Ma
Summary: This study proposes an improved autoencoder to address the challenges of sparsity and uneven distribution of rating data in the recommendation domain. Two recommendation schemes based on the improved autoencoder are presented for rating prediction and top -N ranking tasks. Experimental results demonstrate about 5% and 3% improvements in rating prediction and top -N ranking, respectively. Therefore, the improved model effectively handles the challenges and achieves good recommendation performance.
KNOWLEDGE-BASED SYSTEMS
(2023)
Article
Engineering, Mechanical
Ying Xie, Ying Xu, Jun Ma
Summary: Identical nonlinear oscillators can achieve synchronous states through regulation, while non-identical oscillators can reach phase lock when the coupling channels are controllable. Continuous energy supply and pumping are crucial for periodic or chaotic oscillators and energy exchange occurs when coupling channels are activated. In biological neurons, continuous diffusion of intracellular and extracellular ions activates an electromagnetic field, and the inner field energy can be approximated by the equivalent Hamilton energy of the neuron. This paper investigates the impact of energy diversity on the desynchronization of neurons with parameter diversity, and emphasizes the importance of distinct energy diversity in preventing seizures accompanied by synchronous bursting in neurons.
NONLINEAR DYNAMICS
(2023)
Article
Mathematics, Applied
Fuqiang Wu, Yitong Guo, Jun Ma, Wuyin Jin
Summary: In this paper, an equivalent circuit is designed using two memristive Josephson junctions coupled by a resistor and two inductors to mimic the characteristics of biological neurons. The circuit can reproduce bursting activities similar to neurons through numerical simulation. Additionally, the coupled memristive Josephson junctions can achieve in-phase and antiphase synchronization. The synchronous behaviors are analyzed by discerning the interspike interval of phase difference and average Hamilton energy.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Mathematics, Applied
Veli Baysal, Ramazan Solmaz, Jun Ma
Summary: The signal encoding capacity of the nervous system is significantly related to the spiking regime of neurons. Chaotic fluctuations in the neuronal medium are thought to enhance cognitive functions. External chaotic activity at a suitable level enhances the weak signal encoding performance of neurons, especially when the weak signal frequency matches the chaotic fluctuations-induced sub-threshold oscillations frequencies. This manipulation is explained by chaotic resonance.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Mathematics, Applied
Shidong Zhai, Penglei Zhao, Yongtao Xie, Jun Ma
Summary: This paper introduces a complex network of interaction between human behavior and virus transmission, and analyzes the influence of individual group behavior on virus transmission, as well as the reciprocal influence of virus transmission on individual group behavior. The paper also examines the effects of evolving network structures on cluster synchronization and provides discriminant conditions for distinguishing between aggregation behavior and virus extinction. Through simulations conducted under various conditions, the findings are rigorously validated, confirming their validity and reliability.
Article
Mathematics, Applied
Yitong Guo, Fuqiang Wu, Feifei Yang, Jun Ma
Summary: This study investigates the control mechanism of neuron membrane potential and the adaptive characteristics of neurons. By simulating the physical properties of cell membranes and adding an induction channel, coherence resonance and mode selection under adaptive excitation are discovered. An adaptive control law is proposed to explain the controllability of cell membranes under external stimuli.
Letter
Mathematics, Interdisciplinary Applications
Ping Zhou, Jun Ma, Ying Xu
CHAOS SOLITONS & FRACTALS
(2023)
Article
Engineering, Mechanical
Yitong Guo, Ying Xie, Jun Ma
Summary: This article discusses the methods for setting the energy function of memory resistors in neurons, and proposes two schemes to obtain the equivalent energy function. The research shows that maps are more suitable for investigating neural activities than neuron oscillators.
NONLINEAR DYNAMICS
(2023)
Article
Optics
Feifei Yang, Jun Ma
Summary: A controllable photosensitive neuron model is built by incorporating two phototubes in parallel in the FitzHugh-Nagumo neural circuit. The generated photocurrents from the different illuminations activate different firing modes in this light-sensitive neuron. Switching between the two phototubes induces significant pattern transitions in the neural activity.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Mathematics, Applied
Ya Wang, Liang Wang, Huawei Fan, Jun Ma, Hui Cao, Xingang Wang
Summary: Recent in vivo experiments have shown that astrocytes, a type of glial cell previously thought to provide structural and metabolic support to neurons, actively participate in brain functions by regulating neural firing activities. In this study, the authors propose a complex neuron-astrocyte network model and investigate the role of astrocytes in regulating cluster synchronization behaviors of chaotic neurons. They find that a specific set of neurons form a synchronized cluster while the remaining neurons remain desynchronized. Moreover, the cluster switches between synchronous and asynchronous states in an intermittent fashion, known as the breathing cluster phenomenon. The authors conduct theoretical investigations on the synchronizability of the cluster and reveal that the cluster contents are determined by network symmetry, while the breathing of the cluster is attributed to the interplay between the neural network and the astrocyte.
Article
Computer Science, Artificial Intelligence
D. Vignesh, Jun Ma, Santo Banerjee
Summary: In this article, a discrete fractional Hopfield neural network model is proposed to investigate the influence of external stimuli in the presence of electromagnetic induction and radiation. The network model exhibits chaotic dynamics and coexisting behavior. The study also explores the generation of multi-scroll attractors by varying the level of the pulse function introduced to electromagnetic induction. The findings contribute to our understanding of discrete fractional memristors and shed light on the dynamical behavior of neurons and their electrical activity in the brain.
Article
Computer Science, Artificial Intelligence
Fuqiang Wu, Hao Meng, Jun Ma
Summary: Employing electronic components such as memristor and Josephson junction to imitate biological neurons and synapses has been a popular research topic in recent years. This paper revisits a previous work on memristive Josephson junction and proposes a new model called inductive memristive Josephson junction (L-MJJ) by adding an inductor with internal resistor. The L-MJJ model can reproduce the square-wave bursting behavior of classical neuronal models and achieve bursting synchronization similar to nonlinear coupling neurons. This research aims to build a bridge between superconducting physics and theoretical neuroscience, and demonstrates the potential feasibility of using this junction in designing neuron-inspired computations for larger-scale neuromorphic networks.
Article
Mathematics, Applied
Jun Ma
Summary: Continuous dynamical systems with different nonlinear terms can exhibit rich dynamical characteristics. In this study, reliable algorithms for discretization and equivalent maps are proposed to reproduce similar dynamics as the nonlinear oscillators. The application of scale transformation helps convert maps into equivalent nonlinear oscillators and define energy function. Additionally, a generic memristive term is introduced into the map, which can be used to develop memristive oscillators and clarify the energy function and oscillatory characteristics.
APPLIED MATHEMATICS AND COMPUTATION
(2024)
