Let p be a prime congruent to 1 modulo 4, and let t, u be rational integers such that (t + u √ p )/2 is the fundamental unit of the real quadratic field Q(√p ). The Ankeny-Artin-Chowla conjecture (AAC conjecture) asserts that p will not divide u. This is equivalent to the assertion that p will not divide B(p−1)/2, where Bn denotes the nth Bernoulli number. Although first published in 1952, this...

tant in terms of further investigations and long term outcome. The American Thoracic Society guidelines on the management of malignant pleural effusion, published in 2000, estimated the incidence in the US to be between 80 000 and 160 000 new cases each year. Despite the seemingly clear distinction between exudates and transudates, the clinical reality of determining the cause of a pleural effu...

The parallel numerical solution of large scale elliptic boundary value problems is discussed. We analyze the parallel complexity of two block-circulant preconditioners when the conjugate gradient method is used to solve the sparse linear systems arising from such problems. A simple general model of the parallel performance is applied to the considered shared memory parallel architecture. Estima...

OBJECTIVE The purpose of this study was to determine the frequency of use of play equipment in public schools and parks in Brisbane, Australia, and to estimate an annual rate of injury per use of equipment, overall and for particular types of equipment. METHODS Injury data on all children injured from playground equipment and seeking medical attention at the emergency department of either of ...

BACKGROUND Obesity prevalence has risen in fifty years. While people generally expect media mentions of health risks like obesity prevalence to follow health risk trends, food consumption trends may precede obesity prevalence trends. Therefore, this research investigates whether media mentions of food predate obesity prevalence. METHODS Fifty years of non-advertising articles in the New York ...