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Biomedical Engineering and Bioengineering Commons™
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Full-Text Articles in Biomedical Engineering and Bioengineering
Varying The Time Delay Of An Action Potential Elicited With A Neural-Electronic Stimulator, Robert B. Szlavik, Frank Jenkins
Varying The Time Delay Of An Action Potential Elicited With A Neural-Electronic Stimulator, Robert B. Szlavik, Frank Jenkins
Biomedical Engineering
There have been various theoretical and experimental studies presented in the literature that focus on interfacing neurons with discrete electronic devices such as transistors. It has also been demonstrated experimentally that neural-electronic devices can be used to elicit action potentials in a target neuron in close proximity to the neural-electronic stimulator. The time delay between stimulus and the onset of the neural action potential can be varied by varying the pulse amplitude and width generated by the neural-electronic stimulator (transistor).
Do Microcracks Decrease Or Increase Fatigue Resistance In Cortical Bone?, O. S. Sobelman, J. C. Gibeling, S. M. Stover, S. J. Hazelwood, O. C. Yeh, D. R. Shelton, R. B. Martin
Do Microcracks Decrease Or Increase Fatigue Resistance In Cortical Bone?, O. S. Sobelman, J. C. Gibeling, S. M. Stover, S. J. Hazelwood, O. C. Yeh, D. R. Shelton, R. B. Martin
Biomedical Engineering
Fatigue of cortical bone produces microcracks; it has been hypothesized that these cracks are analogous to those occurring in engineered composite materials and constitute a similar mechanism for fatigue resistance. However, the numbers of these linear microcracks increase substantially with age, suggesting that they contribute to increased fracture incidence among the elderly. To test these opposing hypotheses, we fatigued 20 beams of femoral cortical bone from elderly men and women in load-controlled four point bending having initial strain ranges of 3000 or 5000 microstrain. Loading was stopped at fracture or 106 cycles, whichever occurred first, and microcrack density and length …
A Theoretical Analysis Of Long-Term Bisphosphonate Effects On Trabecular Bone Volume And Microdamage, Jeffry S. Nyman, Oscar C. Yeh, Scott J. Hazelwood, R. Bruce Martin
A Theoretical Analysis Of Long-Term Bisphosphonate Effects On Trabecular Bone Volume And Microdamage, Jeffry S. Nyman, Oscar C. Yeh, Scott J. Hazelwood, R. Bruce Martin
Biomedical Engineering
Bisphosphonates increase bone mass and reduce fracture risk, but their anti-resorptive action may lead to increases in fatigue microdamage. To investigate how bisphosphonate effects influence changes in bone volume and microdamage in the long term, a strain-adaptive model of bone remodeling and microdamage balance was developed for a continuum-level volume of postmenopausal trabecular bone by invoking Frost's mechanostat hypothesis. Both disuse and fatigue microdamage were assumed to stimulate the activation frequency of basic multicellular units (BMUs) such that bone remodeling served to remove excess bone mass and microdamage. Bisphosphonate effects were simulated as follows: low, intermediate, high, or complete suppression …
Long Stemmed Total Knee Arthroplasty With Interlocking Screws: A Computational Bone Adaptation Study, Jeffry S. Nyman, Scott J. Hazelwood, Juan J. Rodrigo, R. Bruce Martin, Oscar C. Yeh
Long Stemmed Total Knee Arthroplasty With Interlocking Screws: A Computational Bone Adaptation Study, Jeffry S. Nyman, Scott J. Hazelwood, Juan J. Rodrigo, R. Bruce Martin, Oscar C. Yeh
Biomedical Engineering
The ability of an interlocking screw fixation technique to minimize bone loss related to stress shielding in the tibia was investigated and compared to the abilities of cement and press-fit fixation. Full bony ingrowth has been associated with greater stress shielding than partial ingrowth; therefore, the effect of intimate bonding of the stem to bone on subsequent bone loss was also studied. A damage-and disuse-based remodeling theory was coupled with a two-dimensional finite element model of the tibia to predict changes in bone remodeling following long stemmed total knee arthroplasty (TKA) for four different fixation techniques (cement, press-fit, interlock with …