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A comprehensive characterization of key mechanisms underlying signal transmission within the human brain remains an unsolved problem. The neuronal surface, composed principally of phosphatidylcholine (POPC), has a known ordering effect on water. This produces highly organized water layers (OWLs) at the neuron-water interface--the neurochemical implications of which are not currently understood. The human brain is 75% water by volume, with folds and grooves to maximize surface area, suggesting that characterization of neuronal OWLs may contribute to an understanding of neuronal signal transmission. Previous experimental work has measured enhanced conductivity of POPC OWLs relative to bulk water. The mechanism underlying this conductivity is still debated. Using quantum chemical methods on a POPC-water interface model system, we present data characterizing OWL conductance. Non-equilibrium Green's function calculation results demonstrate that there is negligible electron transfer-based conductivity through the OWL at biological temperatures. This is consistent with existing studies suggesting the Grotthuss mechanism as the most likely explanation for experimentally observed enhanced conductivity at the POPC-water interface. The broader implications of enhanced proton conductivity at the neuron-water interface are discussed. Key words: interfacial water, organized water, conductance, neuronal lipid, quantum chemical, Introduction The main function of the brain is the transmission and processing of information. Traditionally this has been conceptualized within the context of synaptic transmission. However, the search for alternative [...]

The article presents a complete analysis of the forward and reverse bias capacitance-voltage and conductance-voltage characteristics exhibited by the organic-based Schottky barrier diodes. The impact of the illumination intensity on these electrical properties is also analyzed.

The article presents a newly developed novel method, which can be employed for calculating the maximum conductance that is exhibited by the random nanostructured networks. The approach is also shown to be easily implementable to the one-dimensional conductors.

The magnetic field microscopy technique is employed to explain the conductance of the individual channels present in a carbon nanotube field-effect transistor. The variations observed in the threshold gate bias and transconductance in the different channels of the transistors are also analyzed.

Several studies are conducted to explain the magnetic, as well as the transport properties of the several different diluted granular multilayers with low nominal thicknesses. The conductance of these multilayers is shown to be completely dependent on the temperature.

The conductance method is employed to study the minority, as well as majority carrier responses taking place in the Ge metal-insulator-semiconductor (MIS) interface traps. The discussed MIS capacitors, as well as the electron capture cross section are both shown to be completely independent of the energy.

Byline: Mohammad Mardaani, Ali A. Shokri Theoretical studies on electrical conductance in nanostructures which consist of two semi-infinite leads separated by a typical molecular wire are carried out within Green's function (GF) formalism in the linear regime. For this reason, the GF of extended molecular wire is obtained. Hence, the electrical conductance of the system is derived theoretically, using the GF elements and wire self-energies, within the tight-binding approach and in the ballistic regime. Based on this formalism, the electrical conductance of a linear molecular wire such as poly-acetylene is calculated. The results show that for this chain, a gap appears in the band structure. Moreover, the formalism is generalised to the quasi one dimensional chain such as cyclic benzene wires attached to the metallic leads in the cis and trans classes. Our results show that in the trans class, the conductance of benzene chain decreases as increases the length of the chain.

An analytical modeling based on electrostrictive equations is established for predicting a current that can be obtained from the first flexural mode of a beam which is attached by the electrostrictive polymers. The study is carried out on polyurethane films, either without filler or filled with nanosized SiC or a carbon nanopowder, and they have shown that the incorporation of nanofillers in polyurethane has increased the obtained current.

Planarly aligned cholesteric liquid crystals of short pitch are applied by the in-plane electric field and the reorientation of the director, increasing pitch and flexoelectricity has induced the change of transmission. The flexoelectricity has deterred the change in the birefringence induced by the dielectric response, which is very fast for the effectively thin periodic boundary of the half-pitch of liquid crystal.

The preparation of phase pure multiferroic YMn[O.sub.3] thin films on sapphire (0001) with conducting ZnGaO buffer contact layer by using pulsed laser deposition technique is described and the effect of epitaxial strain on the magneto-electric coupling of these thin films is examined. The studies have shown that it is possible to tune the multiferroic property of YMn[O.sub.3] via changes in ferroelastic route.

SiC doped Mg[B.sub.2]/Ti/Cu wires are made by powder-in-tube technique by using precursor prepared by mixing of Mg[B.sub.2] with Mg in variable ex situ/in situ ratio and the critical current densities are measured. The new process has used the advantages of both techniques, lower Mg[B.sub.2] porosity typical ex situ and better grain connectivity and effective C-substitution through SiC addition obtained by in situ.

The structural, magnetization, heat capacity and electrical resistivity measurements are carried out on a new ruthenate compound [La.sub.3.5][Ru.sub.4][O.sub.13]. The antiferromagnetic (AFM) order is associated with the AFM coupling of Ru ions of the quasi-2-dimensional layers and the resistivity and magnetic data have shown that the quasi-2D substructure has shown semiconducting behavior, while a metallic behavior is expected for the 1D slabs.

Different distributions of Si nanocrystals (nc-Si) in the gate oxide of Al/nc-Si embedded Si[O.sub.2]/p-Si diodes are prepared with Si ion implantation method and the current conduction in the diodes with different nc-Si distributions is examined. The studies have shown that the enhancement in the current conduction is due to the formation of many percolative conduction paths by the nc-Si connecting the gate to the Si substrate.

An omnidirectional perfect transmission is presented in the photonic band gap of a metamaterial, where positive-index and active negative-index materials are randomly stacked. A complete tunneling is obtained in the photonic band gap by introducing the matched impedance at the expected frequency and this kind of transparency is robust against incident angles, optical polarization and system disorder

Mechanical and electronic properties of an antiperovskite-type superconductor ZnN[Ni.sub.3] as well as isostructural and isovalent counterparts MnN[Ni.sub.3] and CdN[Ni.sub.3] are studied by using first-principles calculations. The studies have shown that although the component of M in the compounds has very small contributions to the Fermi level, it might lead to a small shift in the bands near the Fermi level and hence affect the values of the Fermi level, which has resulted in the ZnN[Ni.sub.3] superconductivity at [T.sub.c] while the other two components have shown no indication of superconducting transition down to the temperature.

The control of the magnetic domain nucleation and domain wall motion performed in glass covered amorphous microwires is examined by using the magneto-optical Kerr effect. The studies have shown that the combination of the dc electric current flowing along the wire and the phase shift in the nucleation coil has permitted to control the direction of the domain wall motion.

The analytical results obtained for the ensemble saturation velocity at high fields are applied to one-dimensional (1D) semiconducting graphene nanoribbons as well as semiconductor nanowires with parabolic bandgap. A generalized concept is described for the phonon-limited saturation currents in high-field transport in 1D structure.

The dependence of electronic and optical properties on the Ag thickness in transparent conductive indium tin oxide (ITO)-Ag-ITO (IMI) multilayer films deposited on polyethylene naphthalate flexible substrate by sputtering at room temperature is described. The effect of varying Ag midlayer thickness on transmittance behavior is discussed and a figure of merit is used for comparing the performance of the IMI multilayer systems as a function of Ag thickness.

The combination of in situ electrical measurements with cyclic loading was applied to monitor pressure-induced phase-transformation behavior exhibited by crystalline silicon. The results provide insight into pop-out at a critical Si-III/Si-XII volume that could occur on a subsequent cycle after which Si-III/Si-XII dominated the indent volume.

The measurement of dielectric spectroscopy over a broad frequency range is conducted to investigate the segmental motions in poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV) polyesters. The nearly constant loss (NCL) in PHBV has originated from the vibrational motion model and PHBV might be used as a biodegradable dielectric material.

The thermal conductivity measurements of micromachined 500 nm thick silicon-nitride (Si-N) beams suspended between two Si-N islands, in the temperature range from 77 to 325 K are presented. The measured thermal conductivity has matched with the prediction of the Wiedemann-Franz thermal conductivity determined from electrical conductivity.

An analytical study is used on a one-atom metallic wire for describing the tunneling resonance relative to the atom-lead coupling and for determining the total density of quasiresonant conduction states and the current versus electrochemical potential. The current intensity in the nanowire is expressed in terms of a commutative-semigroup structure.

Two of the most commonly employed test algorithms, the output and transfer curves were explored via a closed-form analysis to demonstrate the effect of parasitic resistance and bias-dependent mobility on device electrical characteristics. The findings for the common overestimation relative to intrinsic and output-estimated mobilities caused solely by gate-bias-dependent mobility and parasitic resistance could be applied for accurate mobility estimation and a dimensionless variable to evaluate the importance of contact resistance.

The fundamental operation of and mechanism of conduction occurring within metal-insulator varistors (MIVs) is examined. The electrical properties displayed by MIVs have shown a strong potential for use in the suppression of fast rise-time transients.

A theoretical model was developed to predict the reflectivity of thin planar surfaces imbedded with long conductive fibers. The predictions obtained from the effective medium model were found to be in good agreement with method of moments (MOM) calculations and experiment.

The direct current conductivity and morphology of a wide range of films made from bundled nanotubes were characterized to explore the conductivity of NT films and determine if it is affected by the properties of NTs themselves. The results obtained demonstrated the significance of the properties of both NTs and the network to develop high conductivity films.