and partly results of my Ph. D. student Richard Cleyton. It is a pleasure to thank the Erwin Schrrdinger Institute and the organisers of the program on Holonomy Groups in Diierential Geometry for their kind hospitality.

background gastroesophageal reflux disease (gerd) is a common problem seen in pediatrics and adolescents. the bravo tm ph monitoring system is a capsule that detects and quantifies the severity of reflux disease. this test is also valuable for evaluation of patients with extra-gastrointestinal manifestations of gerd such as asthma, chronic cough, hoarseness, aspiration pneumonia, and pre/post f...

We show that the complex PT -symmetric periodic potential V (x) = −(iξ sin 2x+ N)2, where ξ is real and N is a positive integer, is quasi-exactly solvable. For odd values of N ≥ 3, it may lead to exceptional points depending upon the strength of the coupling parameter ξ. The corresponding Schrödinger equation is also shown to go over to the Mathieu equation asymptotically. The limiting value of...

A logical explanation as to why the choice of