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In this paper, the effects of external DC electric fields on the neuro-computational properties are investigated in the context of Morris–Lecar (ML) model with bifurcation analysis. We obtain the detailed bifurcation diagram in two-dimensional parameter space of externally applied DC current and trans-membrane potential induced by external DC electric field. The bifurcation sets partition the two-dimensional parameter space in terms of the qualitatively different behaviors of the ML model. Thus the neuron's information encodes the stimulus information, and vice versa, which is significant in neural control. Furthermore, we identify the electric field as a key parameter to control the transitions among four different excitability and spiking properties, which facilitates the design of electric fields based neuronal modulation method.

We report on photoreflectance anisotropy (PRA) spectroscopy of InGaAs/AlAs/AlAsSb coupled double quantum wells (CDQWs) with extremely thin coupling AlAs barriers grown by molecular beam epitaxy (MBE), with no intentional doping. By probing the in-plane interfacial optical anisotropies (OAs), it is shown that PRA spectroscopy has the ability to detect and distinguish semiconductor layers with quantum dimensions, as the anisotropic photoreflectance (PR) signal stems entirely from buried quantum wells (QWs). In order to account for the experimental PRA spectra, a theoretical model at k = 0, based on a linear electro-optic effect through a piezoelectric shear strain, has been employed to quantify the internal electric fields across the QWs. The dimensionalities of the PR lineshapes were tested by using reciprocal (Fourier) space analysis. Such a complementary test is used in order to correctly employ the PRA model developed here.

There has been recent renewed interest in electrocapillary and electrowetting phenomena given its potential for microfluidic actuation and manipulation. Different approaches, in which a variety of electrode configurations have been adopted, however, have dominated the developments in this field. These different approaches have given rise to rich and varied behavior, which has often led to some overlap and confusion in the literature. In this article, we delineate the different observations and elucidate the relationship between these phenomena by re-stressing classical concepts and examining their limitations. Particular emphasis is placed on the distinction between static and spontaneous electrowetting. In the former, a static change in the liquid–solid macroscopic contact angle results when a dielectric film-coated planar plate electrode is employed. In the latter, a spontaneous thin fron-t-running electrowetting film is pulled out ahead of the macroscopic drop with the use of planar parallel line electrodes. This dynamically evolving electrowetting film advances much faster than the macroscopic drop itself and behaves in a self-similar manner analogous to gravity spreading films.

As an environmental vegetable insulation oil, camellia oil will be decomposed into dissolvable gases in the presence of electric field. In this work, the characteristic gases of camellia oil were measured by experiments with partial discharge and breakdown discharge, and the decomposition process of triglyceride, which is the main component of camellia oil, was investigated using molecular simulations (MSs). The experimental results demonstrate that H₂ is the main characteristic gas caused by the partial discharge while C₂H₂ is the main decomposition products for the breakdown discharge. According to the MS results, the C–O bond connected to the center carbon in glycerol breaks initially when the electric field strength is lower, and the C–(O–C) bond in the triglyceride molecule breaks while the electric field strength exceeded critical value with increase of voltage. The decomposition gas generates gradually through decomposition and recombination of radicals, H₂ and CH₄ are the main gas products generated by triglyceride with low electric field strength, while the C₂H₂ increases gradually and becomes the main gas product with the energy of the system accumulated.

Accurate positioning of endocardial catheters inside cardiovascular structures is crucial in electrophysiology (EP) procedures. Improvements in cardiac mapping are required for a better understanding and treatment of arrhythmias. The proposed Electroloc system is a simple, fast and accurate method for endocardial catheters localization. The key features of Electroloc are the use of conventional EP catheters and the simple data processing for providing localization. Electroloc is able to locate any conventional EP mapping catheter with respect to a noncontact EP catheter used as reference, by sequentially passing a sub-threshold current between the mapping electrode (ME) of the mapping catheter and each electrode of the reference catheter. This creates different potential gradients across the reference catheter used to compute two spatial coordinates (horizontal and vertical coordinates) intended for positioning the ME in the cardiac chamber. In vitro experiments demonstrated that Electroloc is a reliable and sensitive system for localizing the ME with a spatial resolution of 2 mm in the vertical localization and of 5 mm in the horizontal localization. Further studies will be required to improve Electroloc accuracy and to extend its sensitivity range.

In earlier models, synaptic plasticity forms the basis for cellular signaling underlying learning and memory. However, synaptic computation of learning and memory in the brain remains controversial. In this paper, we discuss ways in which synaptic plasticity remodels subcellular networks by deflecting trajectories in neuronal state-space as regulating patterns for the synthesis of dynamic continuity that form cognitive networks of associable representations through endogenous dendritic coding to consolidate memory.

We describe a quantum theory of atomic and molecular collisions in the presence of external electromagnetic fields based on the fully uncoupled space-fixed basis representation of the scattering wave functions. The fully uncoupled basis leads to simple expressions for the matrix elements of the Hamiltonian providing all operators of fine and hyperfine interactions as well as the operators describing interatomic and intermolecular interactions are represented as direct products of spherical tensors defined in the laboratory-fixed coordinate system. We present a general expression for the electrostatic interaction operator of two atoms in arbitrary electronic states in terms of uncoupled products of space-fixed spherical tensors and describe recent studies of molecular collisions in external fields.