Alternans of action potential duration has been associated with T wave alternans and the development of arrhythmias because it produces large gradients of repolarization. However, little is known about alternans dynamics in large mammalian hearts. Using optical mapping to record electrical activations simultaneously from the epicardium and endocardium of 9 canine right ventricles, we demonstrat...

A deep insight into the inherent anisotropic optical properties of silicon is required to improve the performance of silicon-waveguide-based photonic devices. It may also lead to novel device concepts and substantially extend the capabilities of silicon photonics in the future. In this paper, for the first time to the best of our knowledge, we present a three-dimensional finite-difference time-...

Polarization control using single plasmonic nanoantennas is of interest for subwavelength optical components in nano-optical circuits and metasurfaces. Here, we investigate the role of two mechanisms for polarization conversion by plasmonic antennas: Structural asymmetry and plasmon hybridization through strong coupling. As a model system we investigate L-shaped antennas consisting of two ortho...

Magnetic levitation, which uses a magnetic field to suspend objects in a fluid, is a powerful and versatile technology. We develop a compact magnetic levitation platform compatible with a smart-phone to separate micro-objects and estimate the density of the sample based on its levitation height. A 3D printed attachment is mechanically installed over the existing camera unit of a smart-phone. Mi...

The effects of semantic and phonetic radicals on Chinese character decoding were examined. Our results suggest that semantic and phonetic radicals are each available for access when a corresponding task emphasizes one or the other kind of radical. But in a more neutral lexical recognition task, the semantic radical is more informative. Semantic radicals that correctly pertain to character meani...

In metropolitan optical networks, with the increasing growth and demand for capability, high bit rate transmission has recently become an important part of communication. Duobinary modulation is more efficient format for transmitting high speed optical signals over bandwidth limited channel. The duobinary modulation format for long haul and WDM transmission links is the one that has a narrow sp...

We demonstrate that the magnitude and sign of the third-order nonlinear susceptibility of plasmonic metals can be controlled by nanostructuring. By patterning a gold film on the nanoscale to support a high quality plasmonic mode, enhancement of its two-photon absorption coefficient by two orders of magnitude is realized. With a response time of <115 fs, nonlinear gold metamaterials have potenti...

Our long-term goal is to understand (1) the properties of densely concentrated, thin layers of planktonic biota that can occur in coastal ocean environments, (2) the interacting physical, chemical, biological and optical processes responsible for establishment, maintenance and breakdown of layers, (3) the impact of thin layers on the dynamics of plankton populations and the performance of optic...

We study the effective third-order nonlinear susceptibility of a graded metal–dielectric composite film of anisotropic particles with weak nonlinearity by invoking the local field effects within the Maxwell–Garnett theory. We further numerically demonstrate that the film can serve as a novel optical material to produce a broad structure in both the linear and the nonlinear response and an enhan...