Biomedical Engineering Reference
In-Depth Information
Figure 5.10
Asymmetry index vs. time for a cell of radius 10
μ
movera
range 0
◦
<θ<
90
◦
.
The asymmetry index is shown for cells of varying radii (10-
100
μ
m) in Fig. 5.11. The results show that for a cell of radius
100
μ
m, equilibrium is reached in about 1,200 seconds. The other
cell radii have not reached equilibrium after 2,000 seconds. The
numerical results, while similar to those given by Poo, were all
somewhat higher than their experimental counterpart. For this
series of runs, the diffusion constant was calculated from radius in
accordance with Eq. (5.4). The result most like Poo's experimental
resultwasacellradiusof50
μ
m,allothercasesreachingequilibrium
either too quickly(100
μ
m) ortoo slowly (10 and20
μ
m).
Using the diffusion rate calculated for the 50
μ
m radius result
(5.1
×
10
−
12
m
−
1
s
−
1
), another series of runs was performed
varying the exposure level from 100 V m
−
1
to 1,000 V m
−
1
,again
to compare with Poo's results. The results shown in Fig. 5.12
are indeed similar to the experimental results obtained by Poo.
Once again, however, the asymmetry ratio is numerically somewhat
overestimated, although this time, the errors appeared smaller than
thepreviouscomparison,the1,000Vm
−
1
casebeingtheworstcase.
The lower exposure levels compared reasonably well, comparing
time againstthe asymmetry ratio.
