Mode-locking pulse generation with MoS2-PVA saturable absorber in both anomalous and ultra-long normal dispersion regimes.

We experimentally demonstrate a stable and simple mode locked erbium doped fiber laser (EDFL) utilizing passive few-layer molybdenum disulfide (MoS2) as a saturable absorber. The MoS2 is obtained by liquid phase exfoliation before it is embedded in a polymer composite film and then inserted in the laser cavity. A stable soliton pulse train started at a low threshold pump power of 20 mW in the anomalous dispersion regime after fine-tuning the rotation of the polarization controller. The central wavelength, 3 dB bandwidth, pulse width, and repetition rate of the soliton pulses are 1574.6 nm, 9.5 nm, 790 fs, and 29.5 MHz, respectively. By inserting a 850 m long dispersion shifted fiber (DSF) in the cavity, a dissipative soliton with square pulse train is obtained in the normal dispersion regime where the operating wavelength is centered at 1567.44 nm with a 3 dB bandwidth of 19.68 nm. The dissipative soliton pulse has a pulse width of 90 ns at a low repetition rate of 231.5 kHz due to the long DSF used. These results are a contribution to the pool of knowledge in nonlinear optical properties of two-dimensional nanomaterials especially for ultrafast photonic applications.

Development of automated image stitching system for radiographic images.

Standard X-ray images using conventional screen-film technique have a limited field of view that is insufficient to show the full bone structure of large hands on a single frame. To produce images containing the whole hand structure, digitized images from the X-ray films can be assembled using image stitching. This paper presents a new medical image stitching method that utilizes minimum average correlation energy filters to identify and merge pairs of hand X-ray medical images. The effectiveness of the proposed method is demonstrated in the experiments involving two databases which contain a total of 40 pairs of overlapping and non-overlapping hand images. The experimental results are compared with that of the normalized cross-correlation (NCC) method. It is found that the proposed method outperforms the NCC method in classifying and merging the overlapping and non-overlapping medical images. The efficacy of the proposed method is further indicated by its average execution time, which is about five times shorter than that of the other method.

Acute lupus pneumonitis in the postpartum period: a case history and review of the literature.

A patient is described who developed acute lupus pneumonitis in the puerperium. The difficulty in arriving at this diagnosis and the confusion with infectious etiologies of postpartum illness is described. Other manifestations of pulmonary disease in systemic lupus erythematosis are discussed, and the literature regarding acute lupus pneumonitis in the postpartum period is reviewed.

Cryosurgical treatment of cervical intraepithelial neoplasia: four-year experience.

Cryosurgical therapy was used to treat 393 patients with cervical intraepithelial neoplasia. Therapeutic success was evaluated in relation to lesion size, grade, and endocervical extension. The overall cure rate with cryosurgical therapy was 84%. Size alone was found to be the major determinant of cryosurgical success. For one-quadrant lesions, there was a 99% cure rate. For two-quadrant lesions, the cure rate was 93%. For three- or four-quadrant lesions, the success rate was only 61%. Lesion size was found to be positively correlated with grade of dysplasia. As the grade of cervical intraepithelial neoplasia progressed, lesion size tended to increase. When this association was controlled for, grade of dysplasia was not a significant determinant of success rate. When endocervical extension occurred, although the upper limits of the lesion were seen, there was a significantly reduced success rate of 64%. Patients with large lesions or endocervical extension are at a much higher risk for failure with cryosurgical treatment. If cryotherapy is chosen for these patients, careful, long-term follow-up is essential to ensure adequate treatment of disease.