Demonstration of a semiconductor external cavity laser using a UVwritten grating in a planar silica waveguide

The authors report the first demonstration of a semiconductor external cavity waveguide laser, modulated at 2.5 Gbit/s over 100 km of standard optical fibre using a UV written grating in a planar silica waveguide as the feedback element     

Oculomotor paralysis. The perspective of a neuro-ophthalmology consultation

Ocular paresis is a usual diagnosis in neuro-ophthalmologic consultation, and its aetiology is indeed a challenge. The authors studied 3400 records concerning this consultation, between 1982 and the third quarter of 1993. During this period 221 cases with ocular paresis were selected. During this retrospective study we point out the following items: the cranial nerve affected; the neuro-ophthalmologic semiology; the aetiology and clinical evolution, according to the age groups. From 221 cases selected, 111 were paresis from the VIth pair (50.2%), 88 from the IIIrd pair (39.8%), 14 multiple paresis (6.4%) and 8 paresis from the IVth pair (3.6%). The most frequent complaint was diplopia (> 90%). As far as the aetiological diagnosis is concerned, this was easier to establish in patients > 50 years of age. In this age group the most usual aetiology was vascular and traumatic pathologies. In younger patients the most frequent pathologies were traumatic and tumoral. The prognostic was better in the vascular group, the paresis recovery being > 50% in all other pathologies, except the tumoral one.     

A general interaction analysis for large deformations

A method is presented for the finite element analysis of the interaction of geometrically and materially non-linear bodies. Interaction is considered at predefined interfaces. Equations for interaction forces are assembled via static condensation, and the solution for these forces is utilized for the full analysis of the problem. An interface function using the interpolating functions is defined to maintain the equilibrium of interaction forces and the displacement compatibility at the interface nodes. The method permits large rotations and slipping as well as the occurrence of new contacts at the interfaces. Additionally, solutions can be found using high- or low-order elements and when nodes at either side of the interface are not aligned.     

Roxatidine versus ranitidine in the treatment of duodenal ulcer: a randomized, double blind, controlled, multicenter study in Thailand

BACKGROUND: Roxatidine acetate is a novel H2-receptor antagonist and several studies have shown that it is effective in healing duodenal ulcers. We evaluated the efficacy of roxatidine in a non-western society with particular different features and its healing of duodenal ulcers was compared in Thailand with that of ranitidine. METHOD: The design was controlled, randomized, double-blind, and multicenter. The study recruited a total of 215 patients who were endoscoped at the start of the trial and then randomized to receive a single capsule of roxatidine acetate, 150 mg, or an identical capsule containing ranitidine, 300 mg, both to be taken at night. Patients were evaluated at 1, 2, and 4 weeks, including endoscopy at the last session, as well as at 6 weeks with repeat endoscopy if the ulcer had not healed. RESULT: Both drugs relieved pain rapidly, usually within a week, and at repeat endoscopy at 4 weeks most ulcers (78%) were healed, 77.0 and 79.5 per cent in ranitidine and roxatidine, and in those patients in whom healing was not completed the healing rate had risen appreciably to 89.8 and 93.8 per cent respectively at 6 weeks. Small ulcers tended to heal quicker than larger ones, but smoking and alcohol intake had no negative effects on the results. CONCLUSION: The study was valid proof that roxatidine, in a single evening dose of 150 mg, was found to be both safe and effective in the rapid healing of duodenal ulcers when compared with 300 mg ranitidine.