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In this study, we present a novel low-frequency electrical stimulation paradigm for mesial temporal lobe epilepsy (MTLE). The paradigm utilizes the hippocampal commissure as a unique stimulation target to simultaneously influence large portions of the bilateral hippocampal network. When applied to an acute rat model of MTLE, animals that received stimulation exhibited an 88% reduction in the signal power of the bilateral epileptiform activity relative to the control group. In addition, the stimulation entrained the hippocampal network's spontaneous epileptiform activity and disrupted its bilateral synchrony.

Compound channels are a common hydraulic section of many alluvial and fluvial systems, serving as conduits for the flow of water and sediment. The proper design of these structures requires an understanding of the entrainment and mixing mechanisms in them. This paper presents a three-dimensional numerical study of lock-exchange flow in a compound channel covering the Reynolds numbers (Re) range of 17000–39000. This study investigates flow structures and mixing patterns for various geometries and flow characteristics. The results show that the entrainment coefficient decreases as the dense flow progresses, and the amplitude of instantaneous mixing fluctuations decreases with an increase in the width of the floodplain and reduced gravity. The averaged flux entrainment profiles show a minimum at $\mathrm{\text{Re}}=27000$ at different times in the front area. In the head area also, a downward concavity can be seen in the profiles around $\mathrm{\text{Re}}=27000$. This study also reveals that changes in floodplain height do not affect the establishment of lobe-and-cleft instability. The wider the floodplain channel, the larger the lobe-and-cleft instability created. Small-scale mixing dominates at high Reynolds numbers, leading to higher fluid mixing.

We experimentally study stochastic resonance (SR) in the human brain through a noise effect for entrainment dynamics of the alpha (α) wave. The measurement has been carried out under the following conditions in order to obtain clear evidence of the SR phenomenon in the central nervous system. The periodic and noisy stimuli are respectively applied to the right and the left eyes of the subject independently. When only periodic and constant (but weak enough) stimulus is applied to the right eye, it does not induce any global entrainment of α-oscillators to the stimulus frequency. In this situation increasing the amplitude of the noise stimulus (frequency bandwidth from 15 to 60 Hz), harmonic entrainment occurs for a certain range of the noise amplitude and shows a sharp peak in the power spectrum of brain waves. Plotting the amplitude of the peak against the noise amplitude, a bell-type shape is seen, i.e. the maximum signal amplitude at an optimum noise. It clearly indicates the SR phenomenon. Taking account of our experimental conditions and set-up, the present SR phenomenon occurs not on the retina but on the visual processing area in the central nervous systems beyond the optic chiasma.

Phase synchronization and entrainment of a linear array of loss modulated Nd:YAG lasers are experimentally investigated. The temporally shifting nature of phase synchronization with increasing modulation depth is studied. Chaotic intensity dynamics changes dramatically with increasing modulation, and exhibit entrainment to the modulation signal. Frequency filtered phase variables, defined from the laser intensity time series, uncover phenomena of phase synchronization and competition for phase synchronization that are otherwise hidden.

We propose a fairly general model of active media by considering of the interaction between pacemakers via their phase response curves. This model describes a network of pulse oscillators coupled by their response to the internal depolarization of mutual stimulations.

First, a macroscopic level corresponding to an arbitrary large number of oscillatory elements coupled globally is considered. As a specific and important case of the proposed model, the bidirectional interaction of two cardiac nodes is described. This case is generalized by means of an additional pacemaker, which can be expounded as an external stimulator. The behavior of such a system is analyzed. Second, the microscopic level corresponding to the representation of cardiac nodes by two-dimensional lattices of pulse oscillators coupled via the nearest neighbors is described. The model is a universal one in the sense that on its basis one can easily construct discrete distributed media of active elements, which interact via phase response curves.

The purpose of this paper is to analyze in some detail the arguably simplest case of diversity-induced resonance: that of a system of globally-coupled linear oscillators subjected to a periodic forcing. Diversity appears as the parameters characterizing each oscillator, namely its mass, internal frequency and damping coefficient are drawn from a probability distribution. The main ingredients for the diversity-induced-resonance phenomenon are present in this system as the oscillators display a variability in the individual responses but are induced, by the coupling, to synchronize their responses. A steady-state solution for this model is obtained. We also determine the conditions under which it is possible to find a resonance effect.

The interaction of dark energy and dark matter has been studied widely using various formalisms in an effort to understand the physics of such gravitational interactions. Such studies are motivated by the idea that they might hold the key to resolving some of the outstanding problems in cosmology. We will consider the relativistic convective variational formalism in our study of dark matter (hereafter DM)-dark energy (hereafter DE) interaction. In particular, we go beyond the gravitational interaction and consider the potential entrainment phenomena involving the two dark-sector constituents. Ours is a formalism paper and focuses on the theoretical considerations that inform the modeling of such interactions.

In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus is considered as the master circadian pacemaker. Each cell in the SCN contains an autonomous molecular clock, and the SCN is composed of multiple single-cell circadian oscillators. The fundamental question is how the individual cellular oscillators, expressing a wide range of periods, interact and assemble to achieve phase synchronization. In natural conditions, the interaction between the SCN neurons is non-negligible and coupling between cells in the SCN is achieved partly by neurotransmitters. Though there have been a lot of works about the synchronization of circadian oscillators coupled by neurotransmitter, most of the works are based on numerical simulation with little theoretical analysis. In this paper, from the theoretical analysis, we prove that the clocks can be synchronized by the neurotransmitter with mathematical knowledge. Our results also show that the coupling among neurons can synchronize circadian oscillators but the synchronized oscillators are not with period of 24 h, which indicates that environmental cues are necessary to entrain oscillators with period of 24 h. This work can offer theoretical basis to study circadian synchronization in a numerical or experimental way.

The dilution equations of coflowing, tee, staged, and alternating diffusers at strong ambient current conditions are derived and verified by experiments. Previous studies on the dilution processes of thermal diffusers are also reviewed. From a comparison of experimental results and the existing equations of previous researches, it was found that the predictions by existing equations agree reasonably well with the observed data under stagnant ambient and weak current conditions. However, the fits by existing equations are very poor when the momentum of the ambient current is strong. Thus, in this study, new equations representing the dilution behavior of the four diffuser types under strong ambient momentum conditions have been derived using the improved theoretical basis. Comparisons with the experimental results show that proposed equations provide accurate predictions, especially when the momentum ratio of ambient current to the effluent discharge is large. The theoretical approaches proposed in this study give better explanations to the dilution behavior of the four diffusers for complete range of the momentum ratio.

An analytical model was developed to explore the effect of swirl action on the mean evolution of a near flow field of turbulent jet. The equations of motion for turbulent flow were integrated to obtain the theoretical model with the aid of boundary layer approximations and the concept of self-preservation of velocity profiles. Vortex breakdown at the core of the jet, a phenomenon associated with swirling jets, was taken into account through the axial velocity distribution. Axial velocity profiles were described in terms of Gaussian curves and azimuthal velocity profiles described in terms of sinusoidal curves. Expressions were obtained which describe the decay of axial and azimuthal maximum velocities and the growth of jet half width. The proposed model proves that the initial swirling degree significantly influences the time-averaged jet characteristics. Collected data from various sources, covering weak to moderate degrees of swirling, were used to verify the theoretical model. The simulated results for the decay of axial and swirling velocities and the jet spread agree closely with the existing experimental findings. Compared to a non-swirling jet, the growth of the jet width is considerably large, and velocity field is suppressed in a swirling jet, and also the core length becomes shorter.

This paper deals with the seawater exchange caused by the density gradient between the outside and inside of Ohfunato Bay using a density profile around the mouth of the bay and velocity profile above the breakwater mound which has been constructed on the bottom of the bay mouth. The field observations are carried out in order to realize seasonal characteristics of current structures and water qualities behavior in Ohfunato Bay. As a result, it is revealed that the mechanism of seawater exchange is greatly influenced by the density intrusion depending on the longitudinal density gradient. When the density of the outside of the bay is smaller than that of the inside, the seawater exchange occurs in the upper layer and cannot be expected in the lower layer. On the other hand, when the density of the outside bay becomes bigger than that of the inside bay, the seawater exchange is accelerated by two types of density currents. One is intrusion of the outside bay water, and the other is outflow owing to an entrainment above the mound.

This paper introduces the notion of inter-organisational time, a dominant temporal institution at the organisational field level, and an environmental dimension absent from the extant literature. I argue that concepts such as temporal institutions and entrainment can help explain persistent dynamics in an organisational field that pace innovative activities. I use Quebec's biopharmaceutical field to illustrate a shift in inter-organisational time since the technology bubble burst. I suggest that including inter-organisational time in future analyses of organisational fields may improve understanding of the strategic context of innovation.

Good communication is indubitably the foundation of effective teamwork. Over time teams develop their own communication styles and often exhibit entrainment, a conversational phenomena in which humans synchronize their linguistic choices. Conversely, teams may experience conflict due to either personal incompatibility or differing viewpoints. We tackle the problem of predicting team conflict from embeddings learned from multiparty dialogues such that teams with similar post-task conflict scores lie close to one another in vector space. Embeddings were extracted from three types of features: (1) dialogue acts, (2) sentiment polarity, and (3) syntactic entrainment. Machine learning models often suffer domain shift; one advantage of encoding the semantic features is their adaptability across multiple domains. To provide intuition on the generalizability of different embeddings to other goal-oriented teamwork dialogues, we test the effectiveness of learned models trained on the Teams corpus on two other datasets. Unlike syntactic entrainment, both dialogue act and sentiment embeddings are effective for identifying team conflict. Our results show that dialogue act-based embeddings have the potential to generalize better than sentiment and entrainment-based embeddings. These findings have potential ramifications for the development of conversational agents that facilitate teaming.

Numerical study is conducted to confirm the effect of round flow path control and back panel open ratio on a performance of open refrigerating showcase in this study. The rounding control is applied to flow path of air discharger in various radii and the punched panel with various open ratios is applied to back panel of showcase. These structural changes have a significant impact on its aircurtain performance because both changes can affect flow pattern of showcase. To prove it, the two-dimensional steady simulation is performed using $k$–$\epsilon$ turbulent model. The performance of showcase is assessed using entrainment factor which is a ratio between cooled air and ambient air at the suction of refrigerating part. As a result of simulation, the curved path at air discharger reduces the entrainment factor by a maximum 9% less than typical design. The curved flow path removes the dead zone at the honeycomb structure of discharger. In addition, it is found that there is an optimal back panel open ratio at the storage space of the showcase. When the back panel open ratio is 0%, the cooled air from the discharge is attached to the cold storage area because of the Cowanda effect. However, the Cowanda effect is eliminated when back panel open ratio increases. Results address that the entrainment factor remains almost the same at back panel open ratio 3.93% or more. Lastly, the simulation of showcase with product in cold storage area is conducted to confirm the structure changes effect on performance of real use showcase according to KS Standard.

Circadian rhythms of the living organisms are 24hr oscillations found in behavior, biochemistry and physiology. Under constant conditions, the rhythms continue with their intrinsic period length, which are rarely exact 24hr. In this paper, we examine the effects of light on the phase of the gene expression rhythms derived from the interacting feedback network of a few clock genes, taking advantage of a computer simulation with Cell Illustrator. The simulation results suggested that the interacting circadian feedback network at the molecular level is essential for phase dependence of the light effects, observed in mammalian behavior. Furthermore, the simulation reproduced the biological observations that the range of entrainment to shorter or longer than 24hr light-dark cycles is limited, centering around 24hr. Application of our model to inter-time zone flight successfully demonstrated that 6 to 7 days are required to recover from jet lag when traveling from Tokyo to New York.

For more than three decades, the inner crust of neutron stars, formed of a solid lattice of nuclear clusters coexisting with a gas of electrons and neutrons, has been traditionally studied in the Wigner-Seitz approximation. The validity of this approximation is discussed in the general framework of the band theory of solids, which has been recently applied to the nuclear context. Using this novel approach, it is shown that the unbound neutrons move in the crust as if their mass was increased.