Opaque selling is a mechanism whereby a seller conceals product or price information from buyers prior to purchase. Over time opaque intermediaries, such as Hotwire and Priceline.com, have emerged as an established distribution channel for the travel industry. The opaque channel has two countervailing effects: it can increase sales by attracting price-sensitive travelers who may otherwise not p...

A key motivation for transparency regulations and disclosure rules is the view that corporations are more opaque than they could be. Traditional arguments attribute this tendency to agency problems between managers on one side and stakeholders and/or outsiders on the other. We propose a completely di erent argument for why corporations limit the ow of information. When secondary markets are sha...

colon transit time study with radio opaque markers is a simple method for assessment of colon motility disorder in patients with chronic idiopathic constipation. appendicitis caused by metallic objects has been reported repeatedly and is very important because of its complications. we report a case of acute appendicitis that was induced by impaction of radio opaque markers after colon transit t...

Complete opacification of a hemithorax on chest X-ray is termed opaque hemithorax (OH) and is a common finding in emergency room patients. Attending physicians encountering an OH should be able to make an immediate decision regarding the most appropriate approach. The differential diagnosis of an OH is primarily based on the volume of the affected hemithorax, as determined by the position of th...

Information leakage can have dramatic consequences on systems security. Among harmful information leaks, the timing occurs whenever an attacker successfully deduces confidential internal information. In this work, we consider that has access (only) to system execution time. We address following timed opacity problem: given a system, private location and final location, synthesize times from ini...