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D C Hanna

Publications and source records attributed to D C Hanna.

At least 19 recordsLinked to original sources
PubMed2004

High-power femtosecond fiber-feedback optical parametric oscillator based on periodically poled stoichiometric LiTaO3.

We demonstrate a synchronously pumped high-gain optical parametric oscillator with feedback through a fiber, using a passively mode-locked Yb:YAG thin-disk laser as a pump source. We obtain as much as 19-W average signal power at a wavelength of 1.45 microm in 840-fs pulses and 7.8 W of idler power at 3.57 microm. The repetition rate of the pulses is 56 MHz, and the transverse beam quality of the generated signal is M2 < 1.6.

Journal Article↗
PubMed2003

Synchronously pumped CdSe optical parametric oscillator in the 9-10 microm region.

Continuous mode-locked operation of a singly resonant, synchronously pumped optical parametric oscillator (SPOPO) based on CdSe has produced idler output tuned over the range of 9.1-9.7 microm, the longest wavelength generated so far to our knowledge from a SPOPO. Average idler powers as high as approximately 70 mW are generated in the crystal. Tandem pumping with a diffraction-grating-tuned parametric oscillator in periodically poled lithium niobate provides a convenient and agile means of tuning the noncritically phase-matched CdSe device. The absence of any detrimental thermal effects in the CdSe crystal suggests that significant further power scaling should be possible, with idler tuning ranges extendable to cover 8-12 microm.

Journal Article↗
PubMed1987

Recurrent breast carcinoma at the time of breast reconstruction.

Detection of recurrent breast carcinoma following reconstruction of mastectomy defects is of concern to plastic surgeons and oncologists. During the past four years we have found recurrent, previously undetected breast cancer in 4 patients at the time of reconstruction. The recurrent disease presented differently in each patient: as fascial thickening, as a small node hidden under a pectoralis muscle stump, as a microscopical tumor contained within the mastectomy scar, and as a small mass which developed during the interim between the last office visit and the scheduled surgery. All of the patients received additional treatment and one has been reconstructed. Our study of these patients prompts the following recommendations: carefully reexamine the patient just prior to reconstruction; biopsy any abnormal tissue; submit all excised mastectomy scars for histological examination; create and examine the recipient pocket before raising a flap; and reconsider the patient for reconstruction following additional cancer therapy.

Adult↗
PubMed1979

Carcinoma of Stensen's duct.

The authors present 2 cases of carcinoma primary in Stensen's duct, one a mucoepidermoid carcinoma and the other an adenoid cystic carcinoma. This is an unusual site for a primary carcinoma and these are apparently the thirteenth and fourteenth cases to be reported in the English literature. The authors review the diagnosis and treatment for primary carcinoma of Stensen's duct.

Carcinoma↗
PubMed1978

Submandibular gland tumors.

Tumors involving the submandibular gland are rare. However, the incidence of malignancy is much higher than in the parotid (approaching 50 percent). In addition, the 5-year survival rate in patients with malignant tumors of the submandibular gland is much poorer in our series--28 percent versus 71.8 percent for the parotid gland. Because of the poor prognosis in patients with malignant tumors involving the submandibular gland we feel that composite resections should be carried out for all tumors except low-grade mucoepidermoid tumors. In addition, postoperative radiation should be given for specific indications (detailed in the article).

Age Factors↗
PubMed1976

Management of recurrent salivary gland tumors.

The management of 129 patients with recurrent tumors of the salivary glands is analyzed, Principles of approaching recurrent tumors and guidelines for their management are outlined in detail. Age distribution, symptoms, time to recurrence, cases that showed possible malignant degeneration, and complications are reviewed. The surgical procedures, recurrence rate, and survival rates are recorded.

Adolescent↗
PubMed1969

Parotid tumors.

Explore the source record for details and available documents.

Facial Paralysis↗