Reply to S. C. Mehrotra

Reply from C. L. Witham and S. N. Baker

We thank Drs Schouten and Campfens for their interest in our paper. We are more optimistic about the practical capabilities of directed coherence than the position they adopt in their letter, but we would also emphasise the need for caution in using these methods. At the basis of directed coherence (Granger causality) methods is an autoregressive model of the signals of interest. For the bivari...

Reply to S. Rastogi et al

Yellow fever vaccine-reply to S. arya

Letters tion centers in Lagos was fully potent, but potency in Osun and Oyo was 016 log 10 to 0.22 log 10 lower than the stipulated level (2). Furthermore, the titer of two vaccine lots that had been frozen after reconstitution from their lyophilized state dropped from the initial 3.15 log 10 to 3.53 log 10 to zero. If the United States were to implement an extended strategy, similar studies of...

Reply to Bonnie Gold ' s Review

With great interest we have read the review of our book by Bonnie Gold that appeared in the MAA online book review column. It is a serious and professional review and we are glad that she found our book "unique and fascinating" and "a significant contribution to our understanding to mathematics' relation to people." We also deeply appreciate her efforts to understand our work (which is not with...

author's reply

it is a great pleasure to receive two valuable comments about our article regarding sudden cardiac death (scd) in young athletes from two well known experts working in the field of preparticipation evaluation and prevention of sports injuries. we, as authors, generally agree with both authors' comments. however, some considerations should be re-emphasized here. .....