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. 2021 Jul 12;21:225. doi: 10.1186/s12890-021-01599-z

Table 1.

Rheological parameters of the sputum using a sputum: additive ratio of 10:4

Untreated Water bicarbonate NaCl
Mean (SD) Mean (SD) p value Mean (SD) p value Mean (SD) p value
For all samples
G′ (at 1 rad/s) 82,037 (± 84,967) 64,556 (± 64,832) 0.0161 41,073 (± 45,478) 0.0009 24,741 (± 35,553) 0.0110
G″ (at 1 rad/s) 20,926 (± 20,403) 16,557 (± 16,337) 0.0597 10,854 (± 11,264) 0.0029 6480 (± 8756) 0.0312
tanδ (at 1 rad/s) 0.2647 (± 0.0426) 0.2665 (± 0.0596) 0.6548 0.3163 (± 0.1631) 0.0049 0.3051 (± 0.0999) 0.5052
G′ (at 10 rad/s) 101,422 (± 109,431) 80,410 (± 83,619) 0.0122 49,784 (± 54,697) 0.0013 47,712 (± 45,942) 0.0223
G″ (at 10 rad/s) 23,882 (± 25,490) 18,108 (± 18,133) 0.0467 11,963 (± 12,200) 0.0051 12,135 (± 10,962) 0.0799
tanδ (at 10 rad/s) 0.2391 (± 0.0479) 0.2575 (± 0.0817) 0.7346 0.3172 (0.1754) 0.0015 0.2823 (± 0.0504) 0.4369
n = 16 n = 16 n = 14 n = 9
For highly elastic sample (G′ > 100 000 Pa)
G′ (at 1 rad/s) 161,725 (± 95,700) 49,150 (± 47,894) < 0.0001 28,770 (± 34,739) < 0.0001 35,445 (± 33,747) < 0.0001
G″ (at 1 rad/s) 39,393 (± 27,405) 12,338 (± 12,035) < 0.0001 6823 (± 7914) < 0.0001 8614 (± 7765) < 0.0001
tanδ (at 1 rad/s) 0.2393 (± 0.0351) 0.2580 (± 0.0727) 0.9311 0.3104 (± 0.1853) 0.1883 0.2875 (± 0.0841) 0.5394
G′ (at 10 rad/s) 204,250 (± 123,409) 60,679 (± 61,262) < 0.0001 35,913 (± 43,801) < 0.0001 46,762 (± 42,154) < 0.0001
G″ (at 10 rad/s) 46,568 (± 35,515) 13,706 (± 13,323) 0.0002 8099 (± 9650) < 0.0001 10,937 (± 9471) 0.0002
tanδ (at 10 rad/s) 0.2192 (± 0.0312) 0.2431 (± 0.0895) 0.8880 0.3259 (± 0.2016) 0.0367 0.2665 (± 0.0522) 0.5963
n = 34 n = 34 n = 28 n = 22
For elastic sample (100 000 Pa > G′ > 1000 Pa)
G′ (at 1 rad/s) 33,999 (± 23,742) 18,133 (± 21,186) 0.0395 17,151 (± 23,067) 0.0398 27,299 (± 38,056) 0.6779
G″ (at 1 rad/s) 8435 (± 5620) 4919 (± 5606) 0.0943 4664 (± 6284) 0.0902 7122 (± 10,032) 0.8262
tanδ (at 1 rad/s) 0.2549 (± 0.0355) 0.2936 (± 0.0536) 0.1204 0.3377 (± 0.1364) 0.0003 0.2949 (0.0671) 0.1623
G′ (at 10 rad/s) 40,702 (± 28,571) 21,513 (± 25,010) 0.0486 20,935 (± 27,391) 0.0583 35,549 (± 50,749) 0.8957
G″ (at 10 rad/s) 9585 (± 6505) 5303 (± 5905) 0.0783 5298 (± 6824) 0.1046 8913 (± 12,723) 0.9811
tanδ (at 10 rad/s) 0.2421 (± 0.0379) 0.2683 (0.0630) 0.7026 0.3427 (± 0.2224) 0.0040 0.2962 (± 0.0835) 0.2315
n = 14 n = 14 n = 12 n = 6
For viscoelastic sample (1000 Pa > G)
G′ (at 1 rad/s) 272.3 (± 416.7) 368.7 (± 864.8) 0.9746 168.7 (± 268.6) 0.9660 729.7 (± 1031.5) 0.3555
G″ (at 1 rad/s) 117.2 (± 200.1) 129.4 (± 320.2) 0.4434 60.7 (± 109.5) 0.9831 183.6 (± 260.8) 0.9834
tanδ (at 1 rad/s) 0.3885 (± 0.0906) 0.3550 (± 0.1660) 0.9032 0.3815 (± 0.0986) 0.9988 0.3333 (± 0.2049) 0.7357
G′ (at 10 rad/s) 198.2 (± 246.7) 415.7 (± 965.8) 0.8411 217.2 (± 349.0) 0.9999 852.7 (± 1338.6) 0.1843
G″ (at 10 rad/s) 74.2 (± 100.8) 149.9 (± 366.57) 0.8290 74.2 (± 136.1)  > 0.9999 226.9 (± 377.3) 0.4675
tanδ (at 10 rad/s) 0.3446 (± 0.1088) 0.3545 (± 0.2431) 0.9991 0.3662 (± 0.2928) 0.9907 0.3766 (± 0.1579) 0.9818