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• Two different FBG line-by-line apodization techniques called as the edge-weak-coupling inscription technique are proposed. • The superiority of the edge-weak-coupling methods in the FBG apodization is demonstrated theoretically and experimentally. • The experiment data visually demonstrates the influence of the coupling strength profile on the apodized FBG performance. The apodization profiles have a great influence on the performance of apodized fiber Bragg gratings (AFBGs). Different apodization profiles can significantly affect the side lobe suppression ratio (SLSR) of AFBGs. In this work, we demonstrate theoretically and experimentally that the reduction of the local coupling strength of Gaussian AFBG edges can promote the side lobe suppression of the AFBG. Compared to the femtosecond laser line-by-line (LbL) inscription method of tailoring the track length, the two proposed different edge-weak-coupling LbL inscription methods improve the SLSR of the AFBGs by about 2.4 dB and 7.2 dB owing to the different reductions of the edge local coupling strength in the Gaussian apodization profiles. The SLSR of the direct-writing AFBG is expected to be improved further by optimizing the coupling strength profile. [ABSTRACT FROM AUTHOR]

Fold-and-thrust belts (FTBs) evolve over a mechanically weak basal décollement that separates the overlying intensely deformed rocks from the underlying less deformed ones. Although deformation structures in FTBs commonly show lateral continuity, a closer inspection reveals distinctive variations in structural style (e.g., fold style) along and across mountain belts. This study uses laboratory-scale viscous models to investigate the influence of lateral décollement strength variations on the spatio-temporal evolution of strain patterns in FTBs. These experiments, simulating crustal-scale deformation, show notable changes in the mode of tectonic wedge growth, including the topographic evolution and ductile strain pattern distribution. For example, the deformation front propagates faster over weakly coupled décollement than the laterally adjacent strongly coupled segment, leading to along-strike variations of the topographic slope and curved outline of the deformation front. Constrictional strain, characteristic of regions of weak coupling, is transient and replaced by flattening strain beyond ∼20 % bulk shortening. The latter prevails in regions over strong décollement, whereas complex strain histories mark the transition zone between weak and strong décollements. Based on our modelling results, we propose that variations in décollement strength may cause the segmentation of deformation processes and the development of transverse faults in FTBs. • We use laboratory models to explain the widespread deformation heterogeneity in fold-and-thrust belts. • Along-strike décollement strength variations in FTBs cause structural segmentation and formation of curved deformation front. • Orogen-transverse faults possibly represent a transition zone between weakly and strongly coupled décollements. • Multiple surface slope breaks in orogenic wedges may result from across-strike variations in décollement strength. [ABSTRACT FROM AUTHOR]

Excessive neural synchronization in the cortico-basal ganglia-thalamocortical circuits in the beta (β) frequency range (12–35 Hz) is closely associated with dopamine depletion in Parkinson's disease (PD) and correlated with movement impairments, but the neural basis remains unclear. In this work, we establish a double-oscillator neural mass model for the cortico-basal ganglia-thalamocortical closed-loop system and explore the impacts of dopamine depletion induced changes in coupling connections within or between the two oscillators on neural activities within the loop. Spectral analysis of the neural mass activities revealed that the power and frequency of their principal components are greatly dependent on the coupling strengths between nuclei. We found that the increased intra-coupling in the basal ganglia-thalamic (BG-Th) oscillator contributes to increased oscillations in the lower β frequency band (12–25 Hz), while increased intra-coupling in the cortical oscillator mainly contributes to increased oscillations in the upper β frequency band (26–35 Hz). Interestingly, pathological upper β oscillations in the cortical oscillator may be another origin of the lower β oscillations in the BG-Th oscillator, in addition to increased intra-coupling strength within the BG-Th network. Lower β oscillations in the BG-Th oscillator can also change the dominant oscillation frequency of a cortical nucleus from the upper to the lower β band. Thus, this work may pave the way towards revealing a possible neural basis underlying the Parkinsonian state. • A two oscillator model is built to explore the Parkinsonian beta oscillations. • Intra- and inter-coupling have different roles in inducing the beta oscillations. • Cortical oscillator may also be the origin of the lower beta oscillations. [ABSTRACT FROM AUTHOR]

The analysis of land-atmosphere water and energy interactions requires reliable representation of soil moisture (SM) and evapotranspiration (ET) coupling strength (ρ). However, ρ in current land surface models (LSMs) is prone to bias and its error sources remain unclear. This study aims to identify error sources controlling LSM ρ biases. To this end, we first use a well-established algorithm to produce debiased reference ρ map based on multi-source remote sensing data. Then, ρ values from three LSMs (Variable Infiltration Capacity (VIC), Catchment Land Surface Model (CLSM), and Noah) in Global Land Data Assimilation System (GLDAS) are evaluated against our reference ρ map. Results show that all the three LSMs demonstrate strong ρ in the northern part of China (dominated by arid and semi-arid climates). In contrast, the biases of modeled ρ are marginal in the (relatively) humid southern part of China. Across the three LSMs, Noah and CLSM contain substantial positive biases in ρ representation, while VIC-based ρ estimates are significantly lower than the remotely sensed reference ρ values. Based on our analysis, it appears that the relative importance of transpiration and soil evaporation determines the overall magnitude of ρ and the inter-model ρ differences. However, the LSMs employ different schemes in land surface energy balance. Therefore, the exact process and/or parameter controlling the transpiration and soil evaporation partitioning may be model-specific. • The SM-ET coupling strengths of GLDAS LSMs are evaluated. • Large coupling differences exist between LSMs in arid and semi-arid climates. • Transpiration fraction dominates inter-model coupling differences. [ABSTRACT FROM AUTHOR]

• A new formula for calculating bibliographic coupling strength is provided. • It is based on the TF-IDF formula as used in information retrieval. • A derived formula for similarity calculation between documents is provided. • The feasibility of these new formulae is shown on a large dataset. We propose a new method for computing the bibliographic coupling strength between two documents. This new method is based on the TF-IDF formula from the field of information retrieval. It is shown that this formula is a valid alternative for the original formula introduced by Kessler and is, from a probabilistic point of view, a correction of the Vladutz-Cook formula. We further define a cosine based similarity formula generalizing the Sen-Gan coupling angle formula. [ABSTRACT FROM AUTHOR]

Abstract Recently, coupling between groups of neurons or different brain regions has been widely studied to provide insights into underlying mechanisms of brain functions. To comprehensively understand the effect of such coupling, it is necessary to accurately extract the coupling strength information among multivariate neural signals from the whole brain. This study proposed a new method named multivariate permutation conditional mutual information (MPCMI) to quantitatively estimate the coupling strength of multivariate neural signals (MNS). The performance of the MPCMI method was validated on the simulated MNS generated by multi-channel neural mass model (MNMM). The coupling strength feature of simulated MNS extracted by MPCMI showed better performance compared with standard methods, such as permutation conditional mutual information (PCMI), multivariate Granger causality (MVGC), and Granger causality analysis (GCA). Furthermore, the MPCMI was applied to estimate the coupling strengths of two-channel resting-state electroencephalographic (rsEEG) signals from different brain regions of 19 patients with amnestic mild cognitive impairment (aMCI) with type 2 diabetes mellitus (T2DM) and 20 normal control (NC) with T2DM in Alpha1 and Alpha2 frequency bands. Empirical results showed that the MPCMI could effectively extract the coupling strength features that were significantly different between the aMCI and the NC. Hence, the proposed MPCMI method could be an effective estimate of coupling strengths of MNS, and might be a viable biomarker for clinical applications. [ABSTRACT FROM AUTHOR]

A new model of neural networks in terms of the memristive Hindmarsh–Rose equations is proposed. Globally dissipative dynamics is shown with absorbing sets in the state spaces. Through sharp and uniform grouping estimates and by leverage of integral and interpolation inequalities tackling the linear network coupling against the memristive nonlinearity, it is proved that exponential synchronization at a uniform convergence rate occurs when the coupling strengths satisfy the threshold conditions which are quantitatively expressed by the parameters. [ABSTRACT FROM AUTHOR]

The robustness of interdependent networks has received extensive attention from the inter-disciplinary fields. In reality, many interdependent systems have interdependence relationships not only between nodes but also between edges. Different from previous studies focusing on edge-coupled interdependent networks without consideration on coupling strength, in this paper, a weighted edge-coupled interdependent network model with coupling strength is proposed. Then, the cascading failure propagation mechanism caused by attacking a small percentage of edges is studied. Based on the self-consistent probability theory, theoretical framework is established to provide the mathematical analysis of robustness of weighted edge-coupled interdependent networks under edge attacks. The current results can help to understand the vulnerability of interdependent networks and provide useful suggestions for the protection and optimization of complex networked systems. • Robustness of weighted edge-coupled interdependent networks with coupling strength under edge attacks is addressed. • Percolation behaviors in the propagation mechanism of cascading failures are theoretically analyzed. • Theoretical framework is based on the self-consistent probability theory. • First-order phase transition can be found with different coupling strength. [ABSTRACT FROM AUTHOR]

Abstract Dark matter (DM) interacts with ordinary matter through weakly coupling to nucleons. We analyze the coupling strength for DM-proton and DM-neutron respectively utilizing the available data from the most sensitive experiments, XENON1T and SuperCDMS, for a higher (>10 GeV/ c 2) and a lower mass (<10 GeV/ c 2) range of DM particles. Subsequently, we calculate the coupling strength constrained by the DAMA claim and a similar experiment (KIMS) using CsI. The results indicate that XENON1T and SuperCDMS are almost fully sensitive to the DM-nucleon coupling strength predicted by the Fermi weak interaction in the higher mass range. As a result, XENON1T is sensitive to the expected small energy associated with the DM-nucleon weak interaction and hence XENON1T provides a strong constrain on the effective mass of DM from ∼1 MeV/ c 2 to ∼100 MeV/ c 2 , which excludes the mass range of DM between 10 GeV/ c 2 to 104 GeV/ c 2 from being detected. In the lower mass range, four experiments are all not sensitive to the DM-nucleon coupling strength expected from the Fermi weak interaction. The DM-nucleon coupling strength, (Z f p + N f n) 2 , determined by the DAMA data can be fully ruled out by the most sensitive experiments. This work launches new direction for the current DM experiments to provide the constrains on DM-nucleon coupling strength, which sheds light on DM-nucleon coupling properties between impinging DM particles and target nucleons with null experimental results. [ABSTRACT FROM AUTHOR]

We report substantial advance of our low-energy angle-resolved photoemission study of nodal quasiparticles in Bi 2 Sr 2 CaCu 2 O 8 + δ . The new data cover the samples from underdoped down to heavily underdoped levels. We also present the nodal Fermi velocities that determined by using an excitation-photon energy of h ν = 7.0 eV over a wide doping range. The consistency between the results with h ν = 8.1 and 7.0 eV allows us to rule out the effect of photoemission matrix elements. In comparison with the data previously reported, the nodal effective mass increases by a factor of ∼ 1.5 in going from optimally doped to heavily underdoped levels. We find a rapid enhancement of the nodal quasiparticle mass at low doping levels near the superconductor-to-insulator transition. The effective coupling spectrum, λ ( ω ) , is extracted directly from the energy derivatives of the quasiparticle dispersion and scattering rate, as a causal function of the mass enhancement factor. A steplike increase in Re λ ( ω ) around ∼ 65 meV is demonstrated clearly by the Kramers-Kronig transform of Im λ ( ω ) . To extract the low-energy renormalization effect, we calculated a simple model for the electron-boson interaction. This model reveals that the contribution of the renormalization at | ω | ≤ 15 meV to the quasiparticle mass is larger than that around 65 meV in underdoped samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • The radiative and non-radiative decay rate calculations reveal the emission and absorption bright and dark modes for the interaction between emitter-heterodimer system. • The location and orientation dependences signify the broadband and directional antenna properties of the plasmonic system. • The near-field enhancement plots simulation provides the directional flow of energy in the dimer system of silver and gold. • The exciting possibility of the interaction between a dipole emitter and a plasmonic system is revealed by the predicted Purcell factor, coupling strength, and quantum yield in relation to the emission energy and distance. Based on the concept of optical nanoantennas, light-matter interaction between metal heterodimer (Ag and Au spherical nanoparticles) and single dipole emitter system are numerically simulated utilizing a MATLAB toolbox MNPBEM17 based on boundary element method (BEM). The precise position and orientation of the dipole emitter systematically controls not only the (non)radiative losses, but also the efficiency of excitation (absorption) and respective emission processes in the vicinity of the plasmonic optical antenna system. The overall (non)radiative decay rates and associated surface charge distributions help estimate the spatio-directional dependency of dipole emitter emission, analogous to that of the SERS enhancement. Furthermore, the Poynting vector analysis of our present hybrid plasmonic antenna system effectively assesses the flow of electromagnetic energy, thus accounting for improvement in both near- and far-field propagation modes. The calculation of Purcell factor and coupling strength along with quantum yield evaluate the detailed optical response of a nanoantenna characteristics simultaneously based on the dipole emitter position and orientation, offering better scope for understanding the underlying mechanisms governing such intriguing interactions in complex geometries as well. [ABSTRACT FROM AUTHOR]

Previous research on articulatory correlates of syllable structure suggests that the temporal organization of syllables varies as a function of the segmental make-up of the onset cluster, yet there is currently little understanding of the details conditioning this variation. We pursue the hypothesis that consonantal coarticulation resistance is one such segment-based determinant of onset-vowel timing. In order to test this we recorded articulography data for Polish and systematically varied the coarticulation resistance of C2 in #C1C2V clusters. We examined singleton and cluster onsets with different vowel-adjacent consonants in terms of temporal lag measurements as done in previous studies as well as in terms of tongue body position measurements. Both analyses revealed parallel results and substantiate the hypothesized interaction of coarticulation resistance of the vowel-adjacent consonant and onset-vowel organization. We discuss how this interaction between articulator dominance and temporal overlap can be modeled within the gestural approach to syllable organization by giving a novel interpretation to the coupling strength parameter in terms of coarticulation resistance. [ABSTRACT FROM AUTHOR]

This paper investigates the group consensus phenomenon for multiple interacting clusters of double-integrator agents in the presence of both cooperative and competitive inter-cluster couplings under two different frameworks, viz., the framework that all agents share the same position and velocity interaction topology and the framework that the position and velocity topologies are modeled by totally independent graphs. Both the case without leaders and the leader-following (meaning there is a single leader for each cluster of agents) case are systematically investigated. Different systems models are systematically analyzed accordingly using various different techniques. Theoretical analysis shows that for most cases, there holds a consistent structural result that group consensus can be achieved if the underlying topology for each cluster of agents satisfies certain connectivity assumptions and further, the intra-cluster couplings are sufficiently strong. Some lower bounds for such strengths are explicitly specified as well. [ABSTRACT FROM AUTHOR]

A cavitation model considering the second-order derivative and bubble-bubble interaction is proposed. The bubble wall velocities are obtained by integrating the modified Rayleigh equation. The bubble-bubble interaction is measured by the coupling strength, which is modified for the hydrodynamic cavitating flows during the evaporation and decreases sharply at the cluster boundary during the condensation. The phase change rates are greatly reduced when the bubble-bubble interaction is considered, except at extremely low vapor volume fraction. Numerical results are given for the collapse of cavitation clusters and the unsteady cavitating flows around two NACA0015 hydrofoils. Comparisons are made with the experimental data and Zwart–Gerber–Belamri cavitation model. [ABSTRACT FROM AUTHOR]

We examined whether movement synchronization is different during coordination with another person than during coordination with a moving object. In addition, the influence of belief in the other person’s agency was assessed. Participants synchronized their lower-arm movements with a computer-controlled rhythmic reference movement. The reference movements were pre-recorded, biological movements and were identical in all conditions. They were presented either by means of a confederate’s arm in a motor-driven manipulandum or by means of movements of the manipulandum alone. To assess the influence of the belief in the confederate’s agency, participants either were or were not informed that the confederate's movements were motor driven. The strength of coupling between the participant’s movements and the reference movements was assessed in terms of the standard deviation of relative phase and the time needed to re-establish the coordination pattern after an unexpected perturbation of the reference signal. Mean relative phase indicated whether the participant was leading or lagging the reference movements. Coupling strength was not affected by the presence of another person in the coordination task, nor by the belief in this person’s agency. However, participants had a stronger tendency to lead while synchronizing with the manipulandum, indicating that they responded differently to the observed kinematics of this moving object than to the kinematics of the confederate’s arm movements, at least when the confederate’s agency was assumed. Hence, although neither the involvement of another person nor the participant’s belief in this person’s agency affected coupling strength , the form of the coupling seemed to be influenced by the former factor, suggesting a different attunement to the reference movements during a joint-action situation. Future research is required to determine whether these interpretations extend to unintentional and bidirectional coordination, in which agency is not only assumed but actually effectuated. [ABSTRACT FROM AUTHOR]

We analyze the plasmonic resonant properties in engineered coplanar graphene nanoribbons by using the finite-difference time-domain (FDTD) method. A numerical analysis is introduced to calculate the coupling strength from frequency. Using this method, the coupling strengths of the first-order plasmon mode are calculated in two kinds of models, one is built with different doping concentration in graphene nanoribbons, the other is created with increasing period. As emulational examples of application of the method, a continuously tuning of the number of transmission dips from one to four is achieved for the first time, which is realized by severally varying the Fermi level of nanoribbons via electrostatic gating. Meanwhile, the novel hybridized plasmon resonances are realized based on periodic graphene nanoribbon pairs. The present paper is helpful for designing coupled plasmonic structures, which demonstrates much promise for applications in graphene-based optoelectronic nanodevices. [ABSTRACT FROM AUTHOR]

This paper attempts to probe into the calcium oscillation behavior in a biological mathematical model, from which the conditions of complete synchronization are derived based on gap-junction. And thus the ranges of coupling strength g are obtained under the ring coupling and the global one for identical cells. It is observed that bigger synchronization threshold is needed for the ring coupling than the global one. In particular, we point out that the unidentical cells require stronger coupling to make the system reach nearly complete synchronization by means of numeric simulation. [ABSTRACT FROM AUTHOR]

The presence of chaos in traffic flow is studied using a modified discrete dynamic coupled map model which is derived from both the flow–density–speed fundamental diagram and Del Castillo’s speed–density model. The modified model employs occupancy as its new variable and introduces a coupling strength with the consideration of effect of the front adjacent vehicle. And we analyze its stability of the control system and provide a procedure to design the decentralized delayed-feedback controllers for the traffic control system. These theoretical results are illustrated by numerical simulations. [ABSTRACT FROM AUTHOR]

• The decoupling effect of soil moisture was observed in the Larix gmelinii forest. • The CDF exhibited a superior performance relative to the ExpF for the study site. • Decoupling significantly reduces the accuracy of subsurface soil moisture simulation. • The incorporation of (de)coupling improves the subsurface soil moisture simulation. Soil moisture is a crucial component of the forest ecosystem because it primarily controls vegetation growth. However, the potential for predicting the subsurface from the surface soil moisture through (de)coupling in boreal larch forest (Larix gmenilii) in China has rarely been investigated. In the present study, the regression and residual as well as cross-correlation analyses were used to evaluate the relationship between the surface (5 cm) and subsurface (10, 20, and 40 cm as well as the profile soil moisture) soil moisture in the Larix gmenilii forest. The applicability of the exponential filter (ExpF) and cumulative distribution function matching (CDF) methods for estimating the subsurface using the surface soil moisture in the study area and the impacts of (de)coupling on the simulation accuracy were assessed. Our results shown that the coupling between surface and subsurface soil moisture decreased with soil depth increasing and decoupling is dominant in the range varying between 0.11 and 0.22 cm3cm−3. The CDF method exhibits superiority for estimating the subsurface soil moisture relative to the ExpF method in the study area. Furthermore, the surface soil moisture values in the coupling range capture the dynamics of the subsurface soil moisture, while decoupling significantly reduces the accuracy of simulating the subsurface soil moisture. Thus, we propose an approach involving the reconstruction of the coupling time series associated with the (de)coupling, which improves the accuracy of the subsurface soil moisture simulation, particularly at depth, where the coupling is weak. Thus, the (de)coupling effect should henceforth be incorporated in the future subsurface soil moisture simulation studies and is helpful to understand the hydrological process of soil, improve regional models and the associated parameters. [ABSTRACT FROM AUTHOR]

Abstract: We study the outcomes in a general measurement with postselection, and derive upper bounds for the pointer readings in weak measurement. The probabilities inferred from weak measurements change along with the coupling strength; and the true probabilities can be obtained when the coupling is strong enough. By calculating the information gain of the measuring device about which path the particles pass through, we show that the “negative probabilities” only emerge for cases when the information gain is little due to very weak coupling between the measuring device and the particles. When the coupling strength increases, we can unambiguously determine whether a particle passes through a given path every time, hence the average shifts always represent true probabilities, and the strange “negatives probabilities” disappear. [Copyright &y& Elsevier]

Abstract: Synchronization of coupled neurons is thought to be important for information communication in neuronal systems. In this paper, phase synchronization of an electrically coupled small-world neuronal network is explored. A small- world Hindmarsh-Rose neuronal network is set up first and then the effects of various network parameters and the heterogeneity of the network on phase synchronization are discussed with some biological explanations. It is demonstrated that the necessary coupling strengths for phase synchronization decrease with the increase of the number of neurons, the degree of nodes and the connection density, and the network heterogeneity has an adverse effect on the synchronizability of the neuronal network. [Copyright &y& Elsevier]

Abstract: Synchronization of electrically coupled chaotic neuronal networks with various topologies is explored in this paper. A general synchronization condition of chaotic neuronal network is obtained by using Master Stability Function method first. Then the condition is applied in chain, ring, star and global coupling networks respectively, while numerical simulations are also performed to check the effectiveness of the condition. It is shown that Master Stability Function method is effective for determining synchronization condition of diffusively coupled neuronal networks and networks with various topologies have different synchronization abilities, which means the speed of information circulation varies a lot in different types of neuronal networks in human brain. [Copyright &y& Elsevier]

Abstract: Dynamical behaviors of unidirectionally, linearly coupled as well as isolated calcium subsystems are investigated by taking into account the internal noise resulting from finite system size and thus small numbers of interacting molecules. For an isolated calcium system, the internal noise can induce stochastic oscillations for a steady state close to the Hopf-bifurcation point, and the regularity of those stochastic oscillations depends resonantly on the system size, exhibiting system-size resonance. For the coupled system consisting of two subsystems, the system-size resonance effect observed in the subsystem subject to coupling is significantly amplified due to the nontrivial effects of coupling. [Copyright &y& Elsevier]

Abstract: The relation between movement amplitude and the strength of interlimb interactions was examined by comparing bimanual performance at different amplitude ratios (1:2, 1:1, and 2:1). For conditions with unequal amplitudes, the arm moving at the smaller amplitude was predicted to be more strongly affected by the contralateral arm than vice versa. This prediction was based on neurophysiological considerations and the HKB model of coupled oscillators. Participants performed rhythmic bimanual forearm movements at prescribed amplitude relations. After a brief mechanical perturbation of one arm, the relaxation process back to the initial coordination pattern was examined. This analysis focused on phase adaptations in the unperturbed arm, as these reflect the degree to which the movements of this arm were affected by the coupling influences stemming from the contralateral (perturbed) arm. The thus obtained index of coupling (IC) reflected the relative contribution of the unperturbed arm to the relaxation process. As predicted IC was larger when the perturbed arm moved at a larger amplitude than did the unperturbed arm, indicating that coupling strength scaled with movement amplitude. This result was discussed in relation to previous research regarding sources of asymmetry in coupling strength and the effects of amplitude disparity on interlimb coordination. [Copyright &y& Elsevier]

Abstract: In this work, the effects of coupling on two calcium subsystems were investigated, the cooperation between coupling and internal noise was also considered. When two non-identical subsystems are in steady state, coupling can induce oscillations, and distinctly enlarge the oscillatory region in bifurcation diagram. Besides, coupling can make the two non-identical oscillators synchronized. With the increment of the coupling strength, the cross-correlation time of the two oscillators firstly increases and then decreases to be constant, showing the synchronization without tuning coupling strength. When internal noise is considered, similar phenomena can also be obtained under the cooperation between coupling and internal noise. [Copyright &y& Elsevier]

Abstract: In a multicellular system of rat hepatocytes and even in an intact liver, cytoplasmic calcium oscillations are synchronized and highly coordinated. In this paper, the mean-field coupling term has been introduced to describe the coupling flux, which is more efficient than gap junctional coupling terms. An optimal coupling strength and an optimal stimulation level for the synchronization of the coupled system have been observed in this paper. Moreover, it has been proved that these results are independent of the cells number. Interestingly, it has been observed that the intracellular noise and the extracellular noise have different effects on the synchronization of the coupled system. [Copyright &y& Elsevier]

Abstract: The frequency of free cytosolic calcium concentration ([Ca2+]) oscillations elicited by a given agonist concentration differs between individual hepatocytes. However, in multicellular systems of rat hepatocytes and even in the intact liver, [Ca2+] oscillations are synchronized and highly coordinated. In this paper, we have investigated theoretically the effects of gap junction permeable to calcium and of the total Ca2+ channel number located on endoplasmic reticulum on intercellular synchronization. Figures of ratio between mean oscillating frequency of coupled cells describe visually the process of phase-locking. By virtue of a set of phase analysis, we can observe a gradual transition from synchronous behavior to nonsynchronous behavior. Furthermore, a signal-to-noise ratio in two dimensional parameter space (coupling strength-total Ca2+ channel number) has suggested that, coherence resonance will occur for appropriate noise and coupling. [Copyright &y& Elsevier]

Abstract: The frequency of free cytosolic calcium concentration ([Ca2+]) oscillations elicited by a given agonist concentration differs between individual hepatocytes. However, in multicellular systems of rat hepatocytes and even in the intact liver, [Ca2+] oscillations are synchronized and highly coordinated. In this paper, we have investigated theoretically the gap junction permeable to calcium and to IP3 on intercellular synchronization by means of a mathematical model, respectively. It is shown that gap junction permeable to calcium and to IP3 are effective on synchronizing calcium oscillations in coupled hepatocytes. Our theoretical results are similar either for the case of Ca2+ acting as coordinating messenger or for the case of IP3 as coordinating messenger. There exists an optimal coupling strength for a pair of connected hepatocytes. Appropriate coupling strength and IP3 level can induce various harmonic locking of intercellular [Ca2+] oscillations. Furthermore, a phase diagram in two-dimensional parameter space of the coupling strength and IP3 level (or the velocity of IP3 synthesis) has been predicted, in which the synchronization region is similar to Arnol''d tongue. [Copyright &y& Elsevier]

Active control optical terahertz modulator based on incorporating n-type GaAs film as the active media into plasmon-induced transparency metasurface, was investigated theoretically and experimentally. From the experimental results it could be found that the resonances transmission of the plasmon-induced transparency was optically modulated and the transmission modulation depth of 87% was achieved at 0.56 THz. This may be due to the fact that when the pump excitation power was tuned from 0 mW to 1000 mW, larger numbers of excited carriers were excited in the electronic "p-n" junction and diffused across the heterojunction to the n-type GaAs film. It increased the conductivity of the n-type GaAs film from 2.29 × 103 S/m to 1.56 × 104 S/m. As a results, the capacitive split gaps of the PIT split-ring resonators were short-circuited and the coupling strength between the resonators was decreased owing to the screening effect caused by the photo-excited carriers. • Optical control of THz PIT based on a GaAs/Si hybrid heterojunction was investigated. • Large numbers of the carriers were generated in GaAs thin film. • These carriers short-circuited the split gap of the PIT split-ring resonators. • These carriers suppress the coupling strength between the PIT resonators. • The resonance transmission of the PIT metamaterial could be modulated optically. [ABSTRACT FROM AUTHOR]

• An integrated framework for probing technology emergence is proposed by combining topic modeling with several new indicators. • The proposed indicators of coupling strength and coupling velocity enrich the relevant methodology on technology emergence. • In the case study on artificial intelligence, some managerial implications for the policy-making could be inspired. With the spillover of the relevant knowledge on AI (artificial intelligence), an increasing number of scientific topics in the field of AI are meeting many opportunities, including transformation and applications in a multitude of areas; therefore, exploring the TE (technology emergence) and TO (technology opportunities) related to AI highlights the meaning and value. To further visualize the TE or underlying TO on AI, a perspective of coupling analyses and a computing framework on coupling relationships between publications and patents are proposed. AI has become a complicated interdisciplinarity field, and increasingly different categories are involved in the domain of AI; therefore, identifying the relevant TE or TO related to AI has become a relatively intractable but valuable problem, and our work presented in this paper can broaden the vision and bring some insights into AI development. Moreover, the proposed indicators of the coupling strength and coupling velocity and their computing methods can provide new insights or perspectives for exploring the TE or TO of a specific topic and can also enrich the relevant methodologies for technical opportunity analysis and coupling analysis between publications and patents. [ABSTRACT FROM AUTHOR]

• Bubble–bubble interaction can suppress or enlarge the radial pulsations of bubbles. • The suppression or enlargement depends on the ultrasound parameters, the radii, the distances and the bubble number. • The frequency response curve of expansion ratio decreases and shifts to left due to bubble–bubble interaction. • The larger the coupling strength is, the more the left-shifting is. Using a model that with or without considering the interaction between bubbles through the radiated pressure waves, numerical simulations of cavitation bubbles have been performed in order to study the effect of the bubble–bubble interaction on radial pulsations of bubbles. Comparing the results obtained by with or without considering the bubble–bubble interaction, it is suggested that the suppression or enlargement property of expansion ratios of bubbles due to the bubble–bubble interaction largely depends on the ultrasound parameters, the ambient bubble radii, the distances between bubbles and the number of bubbles (in multi-bubble environment, the last two aspects can be expressed using the coupling strength). The frequency response curve of expansion ratio decreases and shifts to left due to the bubble–bubble interaction and the larger the coupling strength is, the more the left-shifting is. [ABSTRACT FROM AUTHOR]

• In the present study, for the first time, two types of multilayer in-plane Gr/ h -BN heterostructures (i.e., mixed heterostructures) are constructed, and their thermal transport properties are systematically explored. • The interfacial thermal conductance of multilayer heterostructures does not decrease continuously with increasing number of layers, which is superior to its parent materials (e.g., multi-layer graphene and multi-layer hexagonal boron nitride). • The underlying physical mechanisms are probed through the stress concentration factor, overlap of phonon vibrational spectra, and phonon participation ratio. In particular, the phonon participation rate is calculated from the perspective of MD. Combining both vertical and in-plane two-dimensional (2D) heterostructures opens up the possibility to create an unprecedented architecture using 2D atomic layer building blocks. The thermal transport properties of such multilayer-mixed heterostructures, critical to various applications in nanoelectronics, however, have not been thoroughly explored. Herein, we construct two configurations of multilayer in-plane graphene/hexagonal boron nitride (Gr/ h -BN) heterostructures (i.e., mixed heterostructures) via weak van der Waals (vdW) interactions and systematically investigate the dependence of their interfacial thermal conductance (ITC) on the number of layers using non-equilibrium molecular dynamics (NEMD) simulations. The computational results show that the ITC of two configurations of multilayer in-plane Gr/ h -BN heterostructures (MIGHHs) decrease with increasing layer number n and both saturate at n = 3. Surprisingly, we find that the MIGHH is more advantageous to interfacial thermal transport than the monolayer in-plane Gr/ h -BN heterostructure, which is in strong contrast to the commonly held notion that the multilayer structures of Gr and h -BN suppress the phonon transmission. The underlying physical mechanisms for these puzzling phenomena are probed through the stress concentration factor, overlap of phonon vibrational spectra and phonon participation ratio. In particular, by changing the stacking angle of MIGHH, a higher ITC can be obtained because of the thermal rectification behavior. Furthermore, we find that the ITC in MIGHH can be well-regulated by controlling the coupling strength between layers. Our findings here are of significance for understanding the interfacial thermal transport behaviors of MIGHH, and are expected to attract extensive interest in exploring its new physics and applications. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Sodium gadolinium phosphate oxide and sodium gadolinium oxyfluoride glasses doped with europium oxide were synthesized by melt-quenching method. The density, molar volume and refractive index of the glass samples were carried out. Density and molar volume of oxide glass is more than oxyfluoride glass. The average phosphate to phosphate distance for oxide glass seems to be more than oxyfluoride glass. Polaron radius, inter-ionic radius shows 1.181 nm, 2.88 nm and 1.174 nm, 2.86 nm for oxide glass and oxyfluoride glasses respectively. Oxide electronic Polarizability and optical basicity of the oxide glass are lower than oxy-fluoride glass. Theoretical optical basicity shows higher for oxide glass than oxyfluoride suggesting increase in covalency of the cation to oxygen bonds in oxide glass. Optical band gap was estimated and found to be 3.061eV and 3.204 eV for oxide and oxyfluoride glass. Theoretical two photon absorption coefficient β were evaluated and found to be 11.96 and 10.80 for oxide and oxyfluoride glasses respectively. Electron-phonon coupling strength were evaluated from the phonon side band spectra for the oxide and oxy-fluoride glasses. The asymmetry ratio (R) show higher for NaF doped glass than Na 2 O confirming their role in elevated ionicity for oxyfluoride glass than oxide glass. Furthermore, the glasses were subjected to study for their luminescence properties of the oxide and oxyfluoride glass samples. Image 1 • NaF/Na 2 O glasses were prepared with Eu3+ ions using melt quench technique. • Electron-Phonon coupling strength were measured for 5D 2 transitions. • Theoretical two photon absorption coefficient β were evaluated for these glasses. • Multiphonon relaxation rate shows lower in oxy-fluoride glass than oxide glass. • The asymmetry ratio (R) was evaluated for NaF/Na 2 O doped glasses. [ABSTRACT FROM AUTHOR]

Inspired by the fact that interdependent networks are more apt to describe real-world systems than isolated networks, this paper is devoted to the evolutionary ultimatum game on interdependent lattices. In particular, we aim to study the effects of the coupling strengths (denoted by α) on the emergence of fairness behaviours with two kinds of coupling schemes (i.e., symmetric coupling scheme and asymmetric coupling scheme). Here, the coupling strength determines the interdependency of utility between corresponding partners of the two interdependent lattices. By Monte Carlo simulations and the two-way analysis of variance, we quantitatively confirm that the coupling strength has a significant influence on the emergence of fairness. More specifically, the fairness level can be raised and facilitated when the coupling strength is introduced and increased (less than 1, i.e., with α < 1) compared with the traditional case. By comparison, the symmetric coupling case with mutual information communication performs better than the asymmetric case with unidirectional information communication. Under the symmetric coupling scheme, we find some counterintuitive but interesting phenomena when the coupling strength is set to 1: the greedy strategy (p < q) may occur in a few simulations, but the altruistic strategy (p ≫ q) emerges in most other simulations. In addition, we also investigate the evolution of strategies under the asymmetric coupling scheme and find quite different results compared to those of the symmetric coupling scheme. It is further demonstrated that both the coupling schemes and the coupling strength contribute to the successful promotion of fairness. Furthermore, temporal and spatial distributions and characteristic snapshots are provided to clarify the roles of the coupling strength and coupling scheme in the evolution of fairness. • The impact of network interdependency is denoted by coupling between the utility. • The coupling strength primarily determines the level of the mutual interdependency. • Fairness level can be raised when the coupling strength is introduced and increased. • Symmetric and asymmetric coupling schemes are provided and compared. • The symmetric coupling performs better than the asymmetric coupling. [ABSTRACT FROM AUTHOR]