Email Spam Filtering: A Systematic Review surveys current and proposed spam filtering techniques with particular emphasis on how well they work. The primary focus is on spam filtering in email, while similarities and differences with spam filtering in other communication and storage media - such as instant messaging and the Web - are addressed peripherally. Email Spam Filtering: A Systematic Review examines the definition of spam, the user's information requirements and the role of the spam filter as one component of a large and complex information universe. Well known methods are detailed sufficiently to make the exposition self-contained; however, the focus is on considerations unique to spam. Comparisons, wherever possible, use common evaluation measures and control for differences in experimental setup. Such comparisons are not easy, as benchmarks, measures and methods for evaluating spam filters are still evolving. The author surveys these efforts, their results and their limitations.In spite of recent advances in evaluation methodology, many uncertainties (including widely held but unsubstantiated beliefs) remain as to the effectiveness of spam filtering techniques and as to the validity of spam filter evaluation methods. Email Spam Filtering: A Systematic Review outlines several uncertainties and proposes experimental methods to address them. Email Spam Filtering: A Systematic Review is a highly recommended read for anyone conducting research in the area or charged with controlling spam in a corporate environment.
Gastric secretions contain hydrogen ions at a concentration that is more than one million times higher than their intracellular concentration. This phenomenal gradient as well as the demonstrated ability of gastric juice to digest tissues has motivated clinicians and investigators alike to emphasize acid secretion and acid ablation in studying the pathogenesis and therapy of peptic ulcer disease. Conse- quently, over the past 150 years, we have made considerable progress in under- standing the mechanisms and regulation of acid secretion by the stomach. Not surprisingly, therapy for both peptic disease and mucosal injury has also been predominantly directed at either neutralizing acid or suppressing its production. During the past 10 years, attention has been focused on factors other than acid in the genesis and therapy of ulcer disease. Work done worldwide demon- strated that acid hypersecretion is not a common event in peptic ulcer disease. Therefore, we began realizing that factors other than acid secretion may be important in the genesis of ulcer disease or in gastroduodenal mucosal damage. In addition, new physiological information has established that the gas- troduodenal mucosa is normally protected by a complex series of events includ- ing mucus and bicarbonate secretion, cell renewal, surface mucosal restitution, and preservation of the microvasculature and mucosal proliferative zone.
Zone Labs Articles
Zone Labs Books