Characterization of the responses of brain macrophages to focused ultrasound-mediated blood-brain barrier opening.

The opening of the blood-brain barrier (BBB) by focused ultrasound (FUS) coupled with intravenously injected microbubbles can be leveraged as a form of immunotherapy for the treatment of neurodegenerative disorders. However, how FUS BBB opening affects brain macrophages is not well understood. Here by using single-cell sequencing to characterize the distinct responses of microglia and central nervous system-associated macrophages (CAMs) to FUS-mediated BBB opening in mice, we show that the treatment remodels the immune landscape via the recruitment of CAMs and the proliferation of microglia and via population size increases in disease-associated microglia.

Modeling SARS-CoV-2 infection in individuals with opioid use disorder with brain organoids.

The COVID-19 pandemic has aggravated a preexisting epidemic: the opioid crisis. Much literature has shown that the circumstances imposed by COVID-19, such as social distancing regulations, medical and financial instability, and increased mental health issues, have been detrimental to those with opioid use disorder (OUD). In addition, unexpected neurological sequelae in COVID-19 patients suggest that COVID-19 compromises neuroimmunity, induces hypoxia, and causes respiratory depression, provoking similar effects as those caused by opioid exposure.

Experimental demonstration of robustness and accuracy of a DLI-based OSNR monitor under changes in the transmitter and link for different modulation formats and baud rates.

We experimentally studied the performance of a delay-line interferometer-based optical signal-to-noise ratio (OSNR) monitor that is pre-calibrated in optimal conditions for 25-Gbaud pol-muxed quadrature-amplitude-modulation (QAM) signals, when unpredicted changes outside the monitor occurred either in the transmitter or the link.

Phase correction for a distorted orbital angular momentum beam using a Zernike polynomials-based stochastic-parallel-gradient-descent algorithm.

A stochastic-parallel-gradient-descent algorithm (SPGD) based on Zernike polynomials is proposed to generate the phase correction pattern for a distorted orbital angular momentum (OAM) beam. The Zernike-polynomial coefficients for the correction pattern are obtained by monitoring the intensity profile of the distorted OAM beam through an iteration-based feedback loop. We implement this scheme and experimentally show that the proposed approach improves the quality of the turbulence-distorted OAM beam.

Optical Nyquist channel generation using a comb-based tunable optical tapped-delay-line.

We demonstrate optical Nyquist channel generation based on a comb-based optical tapped-delay-line. The frequency lines of an optical frequency comb are used as the taps of the optical tapped-delay-line to perform a finite-impulse response (FIR) filter function. A single optical nonlinear element is utilized to multiplex the taps and form the Nyquist signal.

100 Tbit/s free-space data link enabled by three-dimensional multiplexing of orbital angular momentum, polarization, and wavelength.

We investigate the orthogonality of orbital angular momentum (OAM) with other multiplexing domains and present a free-space data link that uniquely combines OAM-, polarization-, and wavelength-division multiplexing. Specifically, we demonstrate the multiplexing/demultiplexing of 1008 data channels carried on 12 OAM beams, 2 polarizations, and 42 wavelengths. Each channel is encoded with 100 Gbit/s quadrature phase-shift keying data, providing an aggregate capacity of 100.

Reconfigurable orbital angular momentum and polarization manipulation of 100 Gbit/s QPSK data channels.

We demonstrate reconfigurable orbital angular momentum (OAM) and polarization manipulation of OAM- and polarization-multiplexed 100 Gbit/s quadrature phase shift keying (QPSK) data channels. Each data channel's OAM value and its polarization state can be arbitrarily changed by taking advantage of the unique wavefront profile of OAM beams using liquid crystal on silicon-based spatial light modulators. The manipulation operation introduces a power penalty of <1 dB for 100 Gbit/s QPSK signals.