Abstract: The present disclosure describes luminescent solar concentrators that include photoluminescent nanoparticles. The photoluminescent nanoparticles include a semiconductor nanocrystal that sensitizes the luminescence of a defect. The defect can include, for example, an atom, a cluster of atoms, or a lattice vacancy. The defect can be incorporated into the semiconductor nanocrystal, adsorbed onto, or otherwise associated with the surface of the semiconductor nanocrystal.

Abstract: Methods and systems for securing remotely-operable devices are provided. A security device can receive a plurality of commands to control a remotely-operable device in a remote environment. At least one command in the plurality of commands can include command data that is related to the remotely-operable device. The security device can receive a plurality of responses to the plurality of commands. The security device can process the plurality of commands and the plurality of responses to determine a signature related to an operator that issued the plurality of commands for the remotely-operable device. The security device can determine an identity of the operator based on the signature. The security device can generate an identity report that includes the identity of the operator.

Abstract: An ultrasound based technique for detecting and imaging vibrations in tissue caused by eddies produced during bleeding through punctured arteries or from organs. A clutter signal, normally suppressed in conventional color flow imaging, is employed to detect and characterize local tissue vibrations, to detect internal bleeding in an image, or as an audible or palpable signal, or a readout. Using a tissue vibration image, the origin and extent of vibrations relative to the underlying anatomy and blood flow can be visualized in real time, enabling measurements of vibration amplitude, frequency, and spatial distribution. Bleeding rate can be determined from the frequency and amplitude of the vibrations. Signal processing algorithms usable to identify tissue vibrations from an ensemble of 2D ultrasound data include those based on phase decomposition, spectral estimation using eigendecomposition, and spectral estimation using autoregressive modeling for isolating vibrations from clutter, blood flow, and noise.