A. J. Walker

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In a series of South African populations, mean faecal pH values were found to be: rural and urban blacks, 6.12 and 6.15; Indians 6.21; coloureds (Eur-African-Malay), 6.29; these are significantly lower (p less than 0.01) than that of whites, 6.88. Apart from that of the coloureds, mean values for series of children and adults did not differ significantly.(More)
INTRODUCTION The present study aimed to explore how athletes respond to different behaviors of their opponents. METHODS Twelve moderately to highly physically active participants with at least two years of cycling experience completed four 4-km time trials on a Velotron cycle ergometer. After a familiarization time trial (FAM), participants performed(More)
BACKGROUND AND OBJECTIVES Development of symptomatic pseudocysts after acute pancreatitis is a common occurrence. Endoscopic ultrasound (EUS)-guided transmural drainage has become the treatment of choice for symptomatic pseudocysts. Following this procedure, stent migration can occur. A recently developed fully covered biliary metal stent with antimigration(More)
Background. There has been a growing use of both capsule endoscopy (CE) and double balloon enteroscopy (DBE) to diagnose and treat patients with obscure gastrointestinal blood loss and suspected small bowel pathology. Aim. To compare and correlate sequential CE and DBE findings in a large series of patients at two tertiary level hospitals in Wisconsin.(More)
Nekrashevych conjectured that iterated monodromy groups of quadratic poly-nomials with a pre-periodic kneading sequence have intermediate growth. In this paper we prove intermediate growth for two such groups. We also provide a new proof of intermediate growth for a class of groups containing the Grigorchuk group, previously known to have intermediate(More)
1. Introduction Diffusion controls most physical and chemical processes in the solid Earth. While experiments are limited to conditions of the shallow lower mantle, ab initio calculations allow us to probe conditions at any pressure and temperature. By applying harmonic transition state theory (Vineyard-theory [1]), we have calculated self-diffusion(More)