Submitted on: 27 January 2004.
Revised on: 22 February 2004.
Accepted on: 27 March 2004.
___________________Advances in Gerontology---PLEIADES PUBLISHING INC
Submitted on: 04 October 2008.
Revised on: 08 January 2009.
Accepted on: 03 February 2009.
___________________Advances in Gerontology---PLEIADES PUBLISHING INC
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Submitted on: 27 May 2008.
Revised on: 10 August 2008.
Accepted on: 05 September 2008.
___________________Advances in Gerontology---PLEIADES PUBLISHING INC
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