Chiroptical Response of Aluminum Nanocrescents at Ultraviolet Wavelengths.

Manipulation of plasmon modes at ultraviolet wavelengths using engineered nanophotonic devices allows for the development of high-sensitivity chiroptical spectroscopy systems. We present here an experimental framework based on aluminum-based crescent-shaped nanostructures that exhibit a strong chiroptical response at ultraviolet wavelengths. Through utilization of higher-order plasmon modes in wavelength-scale nanostructures, we address the inherent fabrication challenges in scaling the response to higher frequencies. Additionally, the distinct far-field spectral response types are analyzed within a coupled-oscillator model framework. We find two competing chiroptical response types that contribute toward potential ambiguity in the interpretation of the circular dichroism spectra. The first, optical activity, originates from the interaction between hybridized eigenmodes, whereas the second manifests as a response superficially similar to optical activity but originating instead from differential near-field absorption modes. The study of the chiroptical response from nanoplasmonic devices presented here is expected to aid the development of next-generation chiroptical spectroscopy systems.

Stepping outside the box: an adolescent with a new-onset seizure.

First-time seizures are frightening to children and their families, but the practice parameter recommends minimal evaluation in the emergency department (ED) for the child who presents in a neurologically normal state. We report a 12-year-old girl with seizure whose evaluation in the ED included a computed tomographic scan, largely because of parental anxiety. Computed tomography demonstrated a cerebral cavernous hemangioma or cavernoma. Because of the high recurrence risk of seizures with cavernomas, she was discharged from the ED with a prescription for an antiepileptic drug.