Improving the performance of echo state networks through state feedback.

Reservoir computing, using nonlinear dynamical systems, offers a cost-effective alternative to neural networks for complex tasks involving processing of sequential data, time series modeling, and system identification. Echo state networks (ESNs), a type of reservoir computer, mirror neural networks but simplify training. They apply fixed, random linear transformations to the internal state, followed by nonlinear changes.

Microwave response in a topological superconducting quantum interference device.

Photon detection at microwave frequency is of great interest due to its application in quantum computation information science and technology. Herein are results from studying microwave response in a topological superconducting quantum interference device (SQUID) realized in Dirac semimetal CdAs. The temperature dependence and microwave power dependence of the SQUID junction resistance are studied, from which we obtain an effective temperature at each microwave power level.

αδ-4 Is Required for the Molecular and Structural Organization of Rod and Cone Photoreceptor Synapses.

αδ-4 is an auxiliary subunit of voltage-gated Ca1.4 L-type channels that regulate the development and mature exocytotic function of the photoreceptor ribbon synapse. In humans, mutations in the gene encoding αδ-4 cause heterogeneous forms of vision impairment in humans, the underlying pathogenic mechanisms of which remain unclear.

CaBP1 regulates Ca1 L-type Ca channels and their coupling to neurite growth and gene transcription in mouse spiral ganglion neurons.

CaBP1 is a Ca binding protein that is widely expressed in neurons in the brain, retina, and cochlea. In heterologous expression systems, CaBP1 interacts with and regulates voltage-gated Ca Ca channels but whether this is the case in neurons is unknown. Here, we investigated the cellular functions of CaBP1 in cochlear spiral ganglion neurons (SGNs), which express high levels of CaBP1.

Molecular moieties masking Ca-dependent facilitation of voltage-gated Ca2.2 Ca channels.

Voltage-gated Ca2.1 (P/Q-type) Ca channels undergo Ca-dependent inactivation (CDI) and facilitation (CDF), both of which contribute to short-term synaptic plasticity. Both CDI and CDF are mediated by calmodulin (CaM) binding to sites in the C-terminal domain of the Ca2.

Squeezed light in an optical parametric oscillator network with coherent feedback quantum control.

We present squeezing and anti-squeezing spectra of the output from a degenerate optical parametric oscillator (OPO) network arranged in different coherent quantum feedback configurations. One OPO serves as a quantum plant, the other as a quantum controller. The addition of coherent feedback enables shaping of the output squeezing spectrum of the plant, and is found to be capable of pushing the frequency of maximum squeezing away from the optical driving frequency and broadening the spectrum over a wider frequency band.

400 µJ 79 ns amplified pulses from a Q-switched fiber laser using an Yb(3+)-doped fiber saturable absorber.

We report a passively Q-switched all-fiber laser using a large mode area (LMA) Yb(3+)-doped fiber cladding-pumped at 915 nm and an unpumped single-mode Yb(3+)-doped fiber as the saturable absorber (SA). The saturable absorber fiber and gain fiber were coupled with a free-space telescope to optimize the coupling efficiency between the disparate fibers, preferentially bleaching the SA fiber before gain depletion in the pumped fiber. Using this scheme we first demonstrate a Q-switched oscillator with 40 μJ 79 ns pulses at 1026 nm, and show that pulses can be generated from 1020 nm to 1040 nm.

High-power all-fiber passively Q-switched laser using a doped fiber as a saturable absorber: numerical simulations.

We report a design for a power-scalable all-fiber passively Q-switched laser that uses a large mode area Yb-doped fiber as a gain medium adiabatically tapered to an unpumped single-mode Yb-doped fiber, which serves as a saturable absorber. Through the use of a comprehensive numerical simulator, we demonstrate a passively Q-switched 1030 nm pulsed laser with 14 ns pulse duration and 0.5 mJ pulse energy operating at 200 kHz repetition rate.

The effect of dispersion on spectral broadening of incoherent continuous-wave light in optical fibers.

In addition to fiber nonlinearity, fiber dispersion plays a significant role in spectral broadening of incoherent continuous-wave light. In this paper we have performed a numerical analysis of spectral broadening of incoherent light based on a fully stochastic model. Under a wide range of operating conditions, these numerical simulations exhibit striking features such as damped oscillatory spectral broadening (during the initial stages of propagation), and eventual convergence to a stationary, steady state spectral distribution at sufficiently long propagation distances.

Modal power decomposition of beam intensity profiles into linearly polarized modes of multimode optical fibers.

We calculate the modal power distribution of a randomly and linearly polarized (LP) multimode beam inside a cylindrical fiber core from knowledge of spatial-intensity profiles of a beam emitted from the fiber. We provide an exact analysis with rigorous proofs that forms the basis for our calculations. The beam from the fiber end is collimated by a spherical lens with a specific focal length.

Cryosurgical ablation of liver tumors in colon cancer patients increases the serum total ganglioside level and then selectively augments antiganglioside IgM.

Cryosurgical ablation (CSA) of tumors induces disruptive necrosis. Necrosis may release tumor gangliosides into circulation and they may augment serum antiganglioside antibodies depending on the nature of gangliosides released. The hypothesis is tested by determining the level of serum total gangliosides (STG) and their antibody titers in the sera of colon cancer patients with cryoablated liver tumors.

Serum anti-ganglioside IgM antibodies in soft tissue sarcoma: clinical prognostic implications.

Purpose: Gangliosides are tumor-associated antigens with many biologic functions, including complex interactions with cytokines and other modulators of the immune system. Serum total ganglioside level may be an ideal surrogate marker to predict tumor burden and response to treatment. Antibodies produced against tumor gangliosides may help predict survival.

Serum total gangliosides and TA90-IC levels: novel immunologic markers in colorectal cancer.

Background: Because of the challenge in defining prognostic markers predictive of recurrence or progression, carcinoembryonic antigen (CEA) remains the most frequently used marker in colorectal cancer, despite its low sensitivity. We hypothesized that TA90-IC status and serum ganglioside levels might be useful markers and might be of prognostic significance in colorectal cancer.

Methods: Serum samples from 68 patients undergoing surgical treatment for histologically proven colorectal cancer were analyzed for the presence of CEA, serum gangliosides, and TA90-IC.