Popular culture
Abilities of young people to hear high frequency tones inaudible to those over 25 or so has led to the development of technologies to disperse groups of young people around shops (The Mosquito), and development of a cell phone ringtone, Teen Buzz, for students to use in school, that older people cannot hear. In September 2006 this technique was used to make a dance track called Buzzin. The track had two melodies, one that everyone could hear and one that only younger people could hear. Animals
Many vertebrates such as fish, birds and amphibians do not experience presbycusis in old age as they are able to regenerate their cochlear sensory cells, whereas mammals including humans have genetically lost this ability. A number of laboratories worldwide are conducting comparative studies of birds and mammals that aim to find the differences in regenerative capacity, with a view to developing new treatments for human hearing problems. See also
Presbyopia – age-related degeneration of the eyes

References


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To minimise the cleft, it is necessary to fix together the metacarpals which used to border the cleft. Through repositioning flaps, the wound can be closed. Ueba
Ueba described a less complicated surgery. Transverse flaps are used to resurface the palm, the dorsal side of the transposed digit and the ulnar part of the first web space. A tendon graft is used to connect the common extensor tendons of the border digits of the cleft to prevent digital separation during extension. The closure is simpler, but has cosmetic disadvantage because of the switch between palmar and dorsal skin. Miura and Komada
The release of the first webspace has the same principle as the Snow-Littler procedure. The difference is the closure of the first webspace; this is done by simple closure or closure with Z-plasties. History
Literature shows that cleft hand is described centuries ago. The first reference to what might be considered a cleft hand was by Ambroise Paré in 1575. Hartsink (1770) wrote the first report of true cleft hand. In 1896, the first operation of the cleft hand was performed by Doctor Charles N. Dowed of New York City. However, the first certain description of what we know as a cleft hand as we know it today was described at the end of the 19th century. Symbrachydactyly
Historically, a U-type cleft hand was also known as atypical cleft hand. The classification in which typical and atypical cleft hand are described was mostly used for clinical aspects and is shown in table 1.