Abstract:
:Contact forces are important in maintaining the twining habit of viny stems. A stem twining around a supporting pole puts itself into tension and uses a helical geometry to generate normal loads that are large relative to stem mass per unit length (Silk and Hubbard, Journal of Biomechanics 24(7):599-606, 1991). An electronic pressure-sensing device has been constructed to provide continuous, in vivo measurements of the forces exerted by twining stems. The pressure-sensing element is based on a thin beam load cell that is sheared by a twining stem ascending a split pole. Preliminary results show that after morning glory stems begin to coil around a supporting pole, the twining force increases in an oscillatory fashion over 3 or 4 d, corresponding to positions at least 200 mm from the apex. The force-measuring device should reveal relationships between twining forces and developmental attributes or environmental factors.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Matista A,Silk Wsubject
Has Abstractpub_date
1997-08-01 00:00:00pages
1164issue
8eissn
0002-9122issn
1537-2197pii
84/8/1164journal_volume
84pub_type
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100133
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journal_title:American journal of botany
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journal_title:American journal of botany
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journal_title:American journal of botany
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doi:
更新日期:1998-05-01 00:00:00
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更新日期:2000-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-03-01 00:00:00
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pub_type: 杂志文章
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