Dual-cavity digital laser for intra-cavity mode shaping and polarization control.

In this paper, we present a digital laser for on-demand modes with polarization control based on a single intra-cavity spatial light modulator (SLM). We employ a phase-only SLM as the back reflector in a dual-cavity resonator. We prove that we can digitally control and switch lasing modes with desired linear polarization at video rates.

Learning-based Approaches for Controlling Neural Spiking.

We consider the problem of controlling populations of interconnected neurons using extrinsic stimulation. Such a problem, which is relevant to applications in both basic neuroscience as well as brain medicine, is challenging due to the nonlinearity of neuronal dynamics and the highly unpredictable structure of underlying neuronal networks. Compounding this difficulty is the fact that most neurostimulation technologies offer a single degree of freedom to actuate tens to hundreds of interconnected neurons.

Recurrent Information Optimization with Local, Metaplastic Synaptic Dynamics.

We consider the problem of optimizing information-theoretic quantities in recurrent networks via synaptic learning. In contrast to feedforward networks, the recurrence presents a key challenge insofar as an optimal learning rule must aggregate the joint distribution of the whole network. This challenge, in particular, makes a local policy (i.

Homeostatic dynamics, hysteresis and synchronization in a low-dimensional model of burst suppression.

Burst suppression, a pattern of the electroencephalogram characterized by quasi-periodic alternation of high-voltage activity (burst) and isoelectric silence (suppression), is typically associated with states of unconsciousness, such as in deep general anesthesia and certain etiologies of coma. Recent computational models for burst suppression have attributed the slow (up to tens of seconds) time-scale of burst termination and re-initiation to cycling in supportive physiological process, such as cerebral metabolism. That is, activity-dependent substrate ('energy') depletion during bursts, followed by substrate recovery during suppression.

A mean field model for neural-metabolic homeostatic coupling in burst suppression.

Burst suppression is an inactivated brain state in which the electroencephalogram is characterized by intermittent periods of isoelectric quiescence. Recent modeling studies have suggested an important role for brain metabolic processes in governing the very slow time scales that underlie the duration of bursts and suppressions. In these models, a reduction in metabolism leads to substrate depletion and consequent suppression of action potential firing.

Controlled synthesis of olive-shaped Bi2S3/BiVO4 microspheres through a limited chemical conversion route and enhanced visible-light-responding photocatalytic activity.

Well-defined olive-shaped Bi(2)S(3)/BiVO(4) microspheres were synthesized through a limited chemical conversion route (LCCR), where olive-shaped BiVO(4) microspheres and thioacetamide (TAA) were used as precursors and sulfur source, respectively. The as-synthesized products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission microscope (HRTEM), X-ray photoelectron spectra (XPS), UV-visible diffuse-reflectance spectroscopy (UV-vis DRS), and photoluminescence (PL) spectra in detail. Compared with pure BiVO(4) microspheres and Bi(2)S(3) nanorods, the Bi(2)S(3)/BiVO(4) products showed obviously enhanced photocatalytic activity for the degradation of rhodamine B (Rh B) in aqueous solution under visible-light irradiation (λ > 400 nm).

Single-crystal NaY(MoO4)2 thin plates with dominant {001} facets for efficient photocatalytic degradation of dyes under visible light irradiation.

Single-crystal NaY(MoO(4))(2) thin plates dominated by high-energy {001} facets were hydrothermally synthesized under relatively mild conditions, free of organic additives, seeds and templates. The as-obtained NaY(MoO(4))(2) thin plates showed an excellent visible-light-responding photocatalytic activity for degradation of dyes in water.