Dynamic regime of coherent population trapping and optimization of frequency modulation parameters in atomic clocks.

We theoretically investigate the dynamic regime of coherent population trapping (CPT) in the presence of frequency modulation (FM). We have formulated the criteria for quasi-stationary (adiabatic) and dynamic (non-adiabatic) responses of atomic system driven by this FM. Using the density matrix formalism for Λ system, the error signal is exactly calculated and optimized.

Renal cell carcinoma presenting as polymyalgia rheumatica. Resolution after nephrectomy.

Renal cell carcinoma can present as a variety of paraneoplastic, nonmetastatic conditions, including vasculitis. We describe a patient who presented with the polymyalgia rheumatica syndrome but did not respond to a trial of prednisone. An asymptomatic, nonmetastatic renal cell carcinoma was found during this patient's evaluation.