Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing

The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel activation.In this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy consumption.Simulations of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy consumption.As a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information processing.This discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.

Two‑Dimensional Metal Halides for X‑Ray Detection Applications

Metal halide perovskites have recently emerged as promising candidates for the next generation of X-ray detectors due to their excellent optoelectronic properties.Especially,two-dimensional(2D)perovskites afford many distinct properties,including remarkable structural diversity,high generation energy,and balanced large exciton binding energy.With the advantages of 2D materials and perovskites,it successfully reduces the decomposition and phase transition of perovskite and effectively suppresses ion migration.Meanwhile,the existence of a high hydrophobic spacer can block water molecules,thus making 2D perovskite obtain excellent stability.All of these advantages have attracted much attention in the field of X-ray detection.This review introduces the classification of 2D halide perovskites,summarizes the synthesis technology and performance characteristics of 2D perovskite X-ray direct detector,and briefly discusses the application of 2D perovskite in scintillators.Finally,this review also emphasizes the key challenges faced by 2D perovskite X-ray detectors in practical application and presents our views on its future development.

Electromagnetic Form Factors of Λ Hyperon in the Vector Meson Dominance Model and a Possible Explanation of the Near-Threshold Enhancement of the e^(+)e^(-)→ ΛΛ Reaction

The near-threshold e^(+)e^(-)→ΛΛ reaction is studied with the assumption that the production mechanism is due to a near-ΛΛ-threshold bound state. The cross section of the e^(+)e^(-)→ΛΛ reaction is parameterized in terms of the electromagnetic form factors of Λ hyperon, which are obtained with the vector meson dominance model.It is shown that the contribution to the e^(+)e^(-)→ΛΛ reaction from a new narrow state with quantum numbersJ~(PC)= 1--is dominant for energies very close to threshold. The mass of this new state is around 2231 Me V,which is very close to the mass threshold of ΛΛ, while its width is just a few Me V. This gives a possible solution to the problem that all previous calculations seriously underestimated the near-threshold total cross section of the e^(+)e^(-)→ΛΛ reaction. We also note that the near-threshold enhancement can also be reproduced by including these well established vector resonances ω(1420), ω(1650), Φ(1680), or Φ(2170) with a Flatté form for their total decay width, and a strong coupling to the ΛΛ channel.

Study of singly anti-charmed pentaquark production in b-factory

The b-factories,such as BelleII,BarBar,and LHCb,emphasize the increasing importance of exotic hadron research.In this paper,we discuss the possible production of singly anti-charmed pentaquark states cqqqq from B mesons in a b-factory under SU(3)symmetry analysis.Discussions of both possibilities have been driven by the hypothesis that the pentaquark state considered in this work,known as the lowest lying state P_(c),could be bound or unbound.We find the golden channels for the production of the pentaquark ground states,such as B^(0)→P_(csudu)^((′)0)Σ^(0).We further estimate the branching ratios for the production of the ground states P_(c) from B meson decays.Thus,multiple channels are available for experiments,which may remove certain obstacles to the discovery of new pentaquark states.

Critical Opalescence and Its Impact on the Jet Quenching Parameter q

Jet quenching parameter q is essential for characterizing the interaction strength between jet partons and nuclear matter.Based on the quark-meson model,we develop a new framework for calculating q at finite chemical potentials,in which q is related to the spectral function of the chiral order parameter.

Non-monotonic behavior of jam probability and stretchedexponential distribution in pedestrian counterflow

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow movingin a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians tryingto move to the same target location. By means of computer simulations, we show that the complementary cumulative distributionof the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponentialdistribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by theflow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibitsa non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristicsof the pedestrians may attributed to the anticipation mechanism of collision avoidance.

Analysis of Strong Coupling Constant with Machine Learning and Its Application

We investigate the nature of the strong coupling constant and related physics.Through the analysis of accumulated experimental data around the world,we employ the ability of machine learning to unravel its physical laws.The result of our efforts is a formula that captures the expansive panorama of the distribution of the strong coupling constant across the entire energy range.

Renormalization Group Theory of Eigen Microstates

We propose a renormalization group(RG)theory of eigen microstates,which are introduced in the statistical ensemble composed of microstates obtained from experiments or computer simulations.A microstate in the ensemble can be considered as a linear superposition of eigen microstates with probability amplitudes equal to their eigenvalues.Under the renormalization of a factor b,the largest eigenvalueσ1 has two trivial fixed points at low and high temperature limits and a critical fixed point with the RG relationσb1=bβ/νσ1,whereβandνare the critical exponents of order parameter and correlation length,respectively.With the Ising model in different dimensions,it has been demonstrated that the RG theory of eigen microstates is able to identify the critical point and to predict critical exponents and the universality class.Our theory can be used in research of critical phenomena both in equilibrium and non-equilibrium systems without considering the Hamiltonian,which is the foundation of Wilson’s RG theory and is absent for most complex systems.

Perfect DD^(*) Molecular Prediction Matching the T_(cc) Observation at LHCb

In 2012,we investigated the possible molecular states composed of two charmed mesons[Phys.Rev.D 88(2013)114008;2012 arXiv:1211.5007[hep-ph]].The D^(*)D𝐷system with the quantum numbers of I(J^(P))=0(1^(+))was found to be a good candidate of the loosely bound molecular state.This state is very close to theD*D threshold with a binding energy around 0.47 MeV.This prediction was confirmed by the new LHCb observation of𝑇T^(+)_(cc)[see Franz Muheim’s talk at the European Physical Society conference on high energy physics 2021].

High-fidelity topological quantum state transfers in a cavity-magnon system

We propose a scheme for realizing high-fidelity topological state transfer via the topological edge states in a onedimensional cavity-magnon system.It is found that the cavity-magnon system can be mapped analytically into the generalized Su-Schrieffer-Heeger model with tunable cavity-magnon coupling.It is shown that the edge state can be served as a quantum channel to realize the photonic and magnonic state transfers by adjusting the coupling strength between adjacent cavity modes.Further,our scheme can realize the quantum state transfer between photonic state and magnonic state by changing the cavity-magnon coupling strength.With the numerical simulation,we quantitatively show that the photonic,magnonic and magnon-to-photon state transfers can be achieved with high fidelity in the cavity-magnon system.Spectacularly,three different types of quantum state transfer schemes can be even transformed into each other in a controllable fashion.The Su-Schrieffer-Heeger model based on the cavity-magnon system provides us a tunable platform to engineer the transport of photon and magnon,which may have potential applications in topological quantum processing.

Engineering topological state transfer in four-period Su–Schrieffer–Heeger chain

An extended Su–Schrieffer–Heeger(SSH) model containing four periods of the hopping coefficients, called SSH4 model, is constructed to explore robust quantum state transfer. The gap state protected by the energy gap plays the role of the topological channel where the particle initially located at the last lattice site has the probability to arise at the first and all even lattice sites equally. Serving those sites as ports, a multi-port router can be realized naturally, and the fidelity reaches unity in a wide range of parameters under the long chain and random disorder. Further, when we reduce the third intracell hopping to a small value, the occupancy probability of the second lattice site in every unit cell will reduce to zero, by which a new topological router can be induced. In addition, our SSH4 model can work as a 1/3 beam splitter. Namely, the particle initially occupies the first lattice site and finally appears with equal probability at three lattice sites. We can also realize a 1/2 beam splitter. Our four-period SSH model provides a novel way for topological quantum information processing and can engineer two kinds of quantum optical devices.

Real-time dynamics in strongly correlated quantum-dot systems

We investigate the real-time dynamical properties of Rabi-type oscillation through strongly correlated quantum-dot systems by means of accurate hierarchical equations of motion.It is an extension of the hierarchical Liouville-space approach for addressing strongly correlated quantum-dot systems.We study two paradigmatic models,the single quantum-dot system,and serial coupling double quantum-dot system.We calculate accurately the time-dependent occupancy of quantum-dot systems subject to a sudden change of gate voltage.The Rabi-type oscillation of the occupancy and distinct relaxation time of the quantum-dot systems with different factors are described.This is helpful to understand dissipation and decoherence in real-time dynamics through nanodevices and provides a theoretical frame to experimental investigation and manipulation of molecular electronic devices.

A pseudoclassical theory for the wavepacket dynamics of the kicked rotor model

In this study, we propose a generalized pseudoclassical theory for the kicked rotor model in an attempt to discern the footprints of the classical dynamics in the deep quantum regime. Compared with the previous pseudoclassical theory that applies only in the neighborhoods of the lowest two quantum resonances, the proposed theory is applicable in the neighborhoods of all quantum resonances in principle by considering the quantum effect of the free rotation at a quantum resonance. In particular, it is confirmed by simulations that the quantum wavepacket dynamics can be successfully forecasted based on the generalized pseudoclassical dynamics, offering an intriguing example where it is feasible to bridge the dynamics in the deep quantum regime to the classical dynamics. The application of the generalized pseudoclassical theory to the PT-symmetric kicked rotor is also discussed.

Self organizing optimization and phase transition in reinforcement learning minority game system

Whether the complex game system composed of a large number of artificial intelligence(AI)agents empowered with reinforcement learning can produce extremely favorable collective behaviors just through the way of agent self-exploration is a matter of practical importance.In this paper,we address this question by combining the typical theoretical model of resource allocation system,the minority game model,with reinforcement learning.Each individual participating in the game is set to have a certain degree of intelligence based on reinforcement learning algorithm.In particular,we demonstrate that as AI agents gradually becomes familiar with the unknown environment and tries to provide optimal actions to maximize payoff,the whole system continues to approach the optimal state under certain parameter combinations,herding is effectively suppressed by an oscillating collective behavior which is a self-organizing pattern without any external interference.An interesting phenomenon is that a first-order phase transition is revealed based on some numerical results in our multi-agents system with reinforcement learning.In order to further understand the dynamic behavior of agent learning,we define and analyze the conversion path of belief mode,and find that the self-organizing condensation of belief modes appeared for the given trial and error rates in the AI system.Finally,we provide a detection method for period-two oscillation collective pattern emergence based on the Kullback–Leibler divergence and give the parameter position where the period-two appears.

Thermodynamic limits on neural information processing efficiency

In What is Life?,Schr?dinger defined life as processes maintaining negative entropy.His ideas highlighted physics’ability to interpret complex biological systems,including the human brain.Following in this scientific lineage,a field that seeks to understand brain design,function,and capacities from the perspective of fundamental physical laws has emerged.Specifically,the energy efficiency hypothesis suggests evolutionary pressures shaped neural systems to maximize information processing per energy unit.

Gravitational form factors of the proton from near-threshold vector meson photoproduction

We systematically analyze the quark and gluon gravitational form factors(GFFs)of the proton by connecting the energy-momentum tensor and near-threshold vector meson photoproduction(NTVMP).Specifically,the quark contributions of GFFs are determined by applying global fitting to the cross section of the lightest vector mesonρ0 photoproduction.Combined with the gluon GFFs obtained from heavy quarkonium J/ψphotoproduction data,the complete GFFs are obtained and compared with the experimental results and lattice quantum chromodynamics determinations.In addition,we use the resonance via Padé(RVP)method based on the Schlessinger point method to obtain a model-independent quark D-term distribution through direct analytical continuation of deeply virtual Compton scattering experimental data.If errors are considered,the results obtained with RVP are essentially consistent with those obtained by NTVMP.Moreover,the comprehensive information on GFFs helps to uncover the mass distribution and mechanical properties inside the proton.This study is not only an important basis for delving into the enigmatic properties of the proton,but also has significance for theoretically guiding future JLab and EIC experimental measurements.

Localization of q-form fields on a de Sitter brane in chameleon gravity

Recently,it was found that the vector field can be naturally localized on the thick brane in chameleon gravity.In this work,we extend this study to encompass de Sitter brane scenario.We focus on the localization of q-form fields.The scalar and vector fields can be localized on the de Sitter brane,while the KR field cannot be localized.The condition for localization of the scalar and vector fields is obtained.Furthermore,we investigate the localization characteristics in two examples with given conformal factor b(ϕ).In the first case,the effective potentials and KK modes of the matter fields are obtained asymmetric even though the de Sitter brane has Z2 symmetry.In the second case,volcano-like effective potentials are generated in the de Sitter brane model.

Measurement of integrated luminosities at BESⅢ for data samples at center-of-mass energies between 4.0 and 4.6 GeV

The integrated luminosities of data samples collected in the BESⅢ experiment in 2016-2017 at centerof-mass energies between 4.19 and 4.28 GeV are measured with a precision better than 1% by analyzing large-angle Bhabha scattering events.The integrated luminosities of old datasets collected in 2010-2014 are updated by considering corrections related to detector performance,offsetting the effect of newly discovered readout errors in the electromagnetic calorimeter,which can haphazardly occur.

Electromagnetic form factors of neutron and neutral hyperons in the oscillating point of view

Based on the recent precise measurements by the BESIII collaboration for electron–positron annihilation into a neutron and antineutron pair,the effective form factors of the neutron were determined in the time-like region,and it was found that the effective form factors of the neutron are smaller than those of the proton.The effective form factors of the neutron show a periodic behaviour,similar to those of the proton.Here,a comparative analysis forΛ,∑^(0)and■hyperons is performed.Fits of the available data on the effective form factors ofΛ,∑^(0)and■with zero charge show an interesting phenomenon in the oscillating behavior of their effective form factors.However,this will need to be confirmed by future precise experiments.Both theoretical and experimental investigations of this phenomenon can shed light on the reaction mechanisms of the electron–positron annihilation processes.

Less is more: a new machine-learning methodology for spatiotemporal systems

Machine learning provides a way to use only portions of the variables of a spatiotemporal system to predict its subsequent evolution and consequently avoids the curse of dimensionality.The learning machines employed for this purpose,in essence,are time-delayed recurrent neural networks with multiple input neurons and multiple output neurons.We show in this paper that such kinds of learning machines have a poor generalization ability to variables that have not been trained with.We then present a one-dimensional time-delayed recurrent neural network for the same aim of model-free prediction.It can be trained on different spatial variables in the training stage but initiated by the time series of only one spatial variable,and consequently possess an excellent generalization ability to new variables that have not been trained on.This network presents a new methodology to achieve finegrained predictions from a learning machine trained on coarse-grained data,and thus provides a new strategy for certain applications such as weather forecasting.Numerical verifications are performed on the Kuramoto coupled oscillators and the Barrio-Varea-Aragon-Maini model.