Table 3.

Estimated model parameters obtained with the Kelvin, the arctangent, and the sigmoid models for the thoracic descending aorta (TDA) and carotid artery (CA). Expt refers to the experimental conditions under which the data were collected (S - ex for ovine vessels ex vivo, S - in for ovine vessels in vivo, and H - in for human vessels in vivo), and # refer to the number of data sets used to generate the summary statistics.

Kelvin model
	Expt (#)	r0 cm	Eh mmHg cm	A1 -	b1 ×10−1 sec	J × 10−4 cm4
TDA	S - ex (11)	0.88 ± 0.02	750 ± 78	0.68 ± 0.16†,‡	0.52 ± 0.15	22 ± 6
	S - in (10)	0.79 ± 0.05	493 ± 83	0.98 ± 0.07	0.25 ± 0.07	3.5 ± 1.7
CA	S - ex (11)	0.41 ± 0.03	3295 ± 419	0.84 ± 0.19	0.36 ± 0.14	2.9 ± 1.2
	H - in (10)	0.28 ± 0.04	309 ± 206	0.79 ± 0.18	1.24 ± 0.80	23 ± 13

Arctangent model
	Expt (#)	r0 cm	p0 mmHg	p1 mmHg	A1†,‡-	b1 ×10−1 sec	J × 10−4 cm4
TDA	S -ex (11)	0.62 ± 0.08†	26 ± 6	42 ± 13†	0.90 ± 0.16	0.35 ± 0.11	8.9 ± 4.3
	S -in (10)*	0.59 ± 0.28	229 ± 157‡	25 ± 56‡	1.0 ± 0.01	0.21 ± 0.11	3.3 ± 1.6
CA	S -ex (11)**	0.29 ± 0.02	0 ± 0	6. 2 ± 0.7	1.0 ± 0.00	0.19 ± 0.03	6.1 ± 2.3
	H -in (10)*	0.23 ± 0.06	122 ± 174	90 ± 101	0.93 ± 0.12	0.59 ± 0.20	19 ± 9.6

Sigmoid model
	Expt (#)	r0 cm	k -	α mmHg	A1†,‡-	b1 ×10−1 sec	J × 10−4 cm4
TDA	S -ex (11)	0.93 ± 0.02†	5.8 ± 1.3‡	83 ± 5	0.95 ± 0.08	0.32 ± 0.09†,‡	8.6 ± 4.3
	S -in (9)	0.90 ± 0.06	28 ± 12	89 ± 8	0.93 ± 0.11	0.37 ± 0.11	1.4 ± 1.1
CA	S -ex (11)	0.41 ± 0.03	6.1 ± 0.6	94 ± 3	0.98 ± 0.08	0.27 ± 0.04	3.2 ± 1.4
	H -in (10)	0.31 ± 0.04	13 ± 5.0	113 ± 14	0.98 ± 0.03	0.53 ± 0.16	28 ± 14

^*Large variation in parameter estimates.

^**Two outliers excluded from analysis.

Experimentally measured ex vivo r₀ in ovine thoracic descending aorta was 0.86 ± 0.03 cm, and in ovine CA r₀ was 0.41 ± 0.02 cm.

^†Comparison of means ex vivo vs. in vivo not statistically different (p>0.05).

^‡Comparison of means between anatomical locations not statistically different (p>0.05).