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According to recent statistics from the American Academy of Pediatrics , more than ten thousand children are treated annually for lawnmower-and-tractor related injuries . This tax was designed to fund World War I and was instituted in an era where telephones were a luxury . Hopkins scientist Victor A. McKusick , M.D ., began establishing the clinical definitions of Marfan syndrome in the 1950s , but its molecular roots were not known until the late 1980s when Dietz and other researchers demonstrated that the primary defect was in the gene encoding fibrillin . Traditionally , scientists waited 10 to 12 weeks after conception to diagnose Marfan syndrome , says Hal Dietz , M.D ., lead investigator of the study , which appears in the August issue of Nature Medicine . Well , World War I should be paid for by now and phones are certainly no longer a luxury item . Eric D. Young , Ph.D ., professor of biomedical engineering , of neuroscience and of otolaryngology ( head and neck surgery ) at Johns Hopkins , has shown that our ability to localize sound is a completely different process from our ability to hear and is highly dependent on the external ear .