Letters and Viewpoints Letters to the Editor and Viewpoints are welcome. Letters

to the Editor discuss material recently published in the Jour-nal. Letters will have the best chance of acceptance if they are received within 8 weeks of an article’s publication. Letters to the Editor may be published with a response from the authors of the article being discussed. Discussions beyond the initial letter and response will not be published. Letters to the Editor are not usually peer reviewed, but the Journal may invite replies from the authors of the original publication. Viewpointspertain to issues of general interest, even if they are not related to items previously published (such as unique techniques, brief technology updates, technical notes, and so on). Please note the following criteria for Letters an