Continuous ultraviolet to blue-green astrocomb.

Cosmological and exoplanetary science using transformative telescopes like the ELT will demand precise calibration of astrophysical spectrographs in the blue-green, where stellar absorption lines are most abundant. Astrocombs-lasers providing a broadband sequence of regularly-spaced optical frequencies on a multi-GHz grid-promise an atomically-traceable calibration scale, but their realization in the blue-green is challenging for current infrared-laser-based technology. Here, we introduce a concept achieving a broad, continuous spectrum by combining second-harmonic generation and sum-frequency-mixing in an MgO:PPLN waveguide to generate 390-520 nm light from a 1 GHz Ti:sapphire frequency comb.

Chronic T-cell Lymphocytic Leukemia in a Black Swan ( Cygnus atratus ): Diagnosis, Treatment, and Pathology.

An asymptomatic 14-year old, male black swan ( Cygnus atratus ) housed at a zoological institution was presented for routine preshipment examination. Hematologic findings indicated that the bird had a severe lymphocytic leukocytosis, consistent with chronic lymphocytic leukemia. Radiographs showed the presence of multiple soft tissue masses within the caudal coelomic cavity; ultrasound showed one mass to be an enlarged spleen, a cystic mass near the gonads, and a mass suspected to be associated with the ventriculus.