Frequency modulated hybrid photonic crystal laser by thermal tuning.

We demonstrate frequency modulation (FM) in an external cavity (EC) III-V/silicon laser, comprising a reflective semiconductor optical amplifier (RSOA) and a silicon nitride (SiN) waveguide vertically coupled to a 2D silicon photonic crystal (PhC) cavity. The PhC cavity acts as a tunable narrowband reflector giving wavelength selectivity. The FM was achieved by thermo-optical modulation of the reflector via a p-n junction. Single-mode operation was ensured by the short cavity length, overlapping only one longitudinal laser mode with the reflector. We investigate the effect of reflector modulation theoretically and experimentally and predict a substantial tracking of the resonator by the laser frequency with very small intensity modulation (IM).

Preoperative irradiation and radical cystectomy for stages T2 and T3 squamous cell carcinoma of the bladder.

We treated 25 patients who had muscle invasive pure squamous cell carcinoma of the bladder with preoperative radiation and cystectomy. At operation the tumors in 10 patients (40%) were downstaged--3 of 5 from stage T2, 3 of 4 from stage T3a and 4 of 16 from stage T3b, while 6 patients (24%) had no residual tumor (pT0). The actuarial 5-year survival rate for all patients was 50%. Disease recurred in the pelvis in 7 patients, none of whose tumors had been downstaged (6 died of cancer). Median survival of patients with a pelvic recurrence was 9 months and without recurrence it was 86.7 months (p = 0.03). No patient whose tumor was downstaged had a recurrence or died of bladder cancer. We conclude that irradiation before cystectomy in patients with squamous cell bladder cancer may protect against pelvic recurrence, which is the predominant cause of death. Because effective adjuvant chemotherapy is not available to treat squamous cell carcinoma as it is for transitional cell carcinoma, we recommend irradiation before cystectomy for locally advanced squamous cell carcinoma of the bladder.

Foreign body aspiration of grass inflorescences as a cause of hemoptysis.

Although the sparsity of reports in the literature suggest aspiration of grass inflorescence is rare, in certain areas of the southern United States, aspiration of this type of foreign body is not so uncommon. Four cases of aspiration of Hordeum pusillium, often referred to as "cheat grass" are reported: three of the four patients had hemoptysis. The highest incidence of inhaled foreign bodies usually occur in young children, but all our four patients were older children or adolescents. The clinical manifestations of grass inflorescence are of the following two types: (1) the "lodging" type in which inflorescences remain in the respiratory passages causing bronchial obstruction with pneumonitis; and (2) the "extrusive type" in which the inflorescences migrate into the periphery of the lung and through the chest wall.