The addition of a chiral non-racemic dopant to a nematic liquid crystal (LC) has the effect of transferring the molecular chirality to the phase organization and a chiral nematic phase is formed. This molecular chirality amplification in the LC provides a unique possibility for investigating the relationship between molecular structure, intermolecular interactions, and mesoscale organization. I...

The current state of the art for identification of motor related neural activity during deep brain stimulation (DBS) surgery utilizes manual movements of the patient's joints while observing the recorded raw data of a single electrode. Here we describe an intra-operative method for detection of the motor territory of the subthalamic nucleus (STN) during DBS surgery. The method incorporates eigh...

Topological quantum field theories containing matter fields are constructed by twisting N = 2 supersymmetric quantum field theories. It is shown that N = 2 chiral (antichiral) multiplets lead to topological sigma models while N = 2 twisted chiral (twisted antichiral) multiplets lead to Landau-Ginzburg type topological quantum field theories. In addition, topological gravity in two dimensions is...

The relationship between discreteand continuous-time State Task Network (STN) representations is studied. We show that the continuous-time model of Maravelias and Grossmann (2003) is a generalization of the discrete-time model of Shah et al. (1993). More specifically, discrete-time models can be shown to be a special case of continuous-time models if two restrictions are imposed on the latter: ...

I describe new phases of a chiral liquid crystal with nematic and hexatic order. I find a conical phase, similar to that of a cholesteric in an applied magnetic field for Frank elastic constants K2 > K3. I discuss the role of fluctuations in the context of this phase and the possibility of satisfying the inequality for sufficiently long polymers. In addition I discuss the topological constraint...

In the framework of linear elasticity, we study the limit of a class of discrete free energies modeling strain-alignment-coupled systems by a rigorous coarse-graining procedure, as the number of molecules diverges. We focus on three paradigmatic examples: magnetostrictive solids, ferroelectric crystals and nematic elastomers, obtaining in the limit three continuum models consistent with those c...

A Simple Temporal Network (STN) is a structure containing time-points and temporal constraints that an agent can use to manage its activities. A Simple Temporal Network with Uncertainty (STNU) augments an STN to include contingent links that can be used to represent actions with uncertain durations. The most important property of an STNU is whether it is dynamically controllable (DC)—that is, w...

An individual defect in a nematic liquid crystal moves not only in response to its interaction with other defects but also in response to an external field. We analyze the motion of a wedge disclination in the presence of an applied field of strength H . We neglect backflow and seek steadily travelling patterns. The stationary picture yields a semi-infinite wall of strength π, bounded by the de...

We have investigated the magnetoelectric properties of (Ca1−xSrx)2CoSi2O7 (0 ≤ x ≤ 1) crystals with a quasi-two-dimensional structure. In Ca2CoSi2O7 (x = 0), a canted antiferromagnetic transition occurs at 5.6 K. The transition temperature TN is increasing with increasing Sr concentration, and the rises of the magnetization and dielectric constant become larger. Since the dielectric constant sh...