Abstract:
:We investigated the utility of ICA for evaluation of fetal rhythm in five uncomplicated twin pregnancies and in five twin pregnancies complicated by fetal arrhythmia. Using objective and subjective criteria, we sought to determine how the signal-to-noise ratio, signal fidelity and interference rejection are affected when synthesizing the fetal signal using all the signal-containing ICA components (rank-p ICA) versus using the single dominant component (rank-1 ICA). The signal of each fetus was most commonly distributed over 1 or 2 ICA components, as previously observed in studies of singleton pregnancies; however, in 8 of 26 (31%) cases the signal of each fetus was distributed over 3, 4 or even 5 ICA components. Rank-1 ICA provided the highest SNR and interference rejection, but at the cost of reduced signal fidelity. Our results corroborate that in twin pregnancies, including twin pregnancies complicated by fetal arrhythmia, rank-1 ICA is very effective in isolating the QRS complexes of each fetus; however, it has some limitations when used for fetal rhythm evaluation due to signal distortion. Occasionally, rank-1 ICA completely separates the P-wave and the T-wave from the QRS complex, thus requiring the mixing of several ICA components to achieve acceptable signal fidelity.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Mensah-Brown NA,Lutter WJ,Comani S,Strasburger JF,Wakai RTdoi
10.1088/0967-3334/32/1/004subject
Has Abstractpub_date
2011-01-01 00:00:00pages
51-64issue
1eissn
0967-3334issn
1361-6579pii
S0967-3334(11)60778-2journal_volume
32pub_type
杂志文章abstract::Electrical impedance tomography (EIT) is very sensitive to deformations of the medium boundary shape. For lung imaging, breathing and changes in posture move the electrodes and change the chest shape, resulting in image artefacts. Several approaches have been proposed to improve the reconstructed images; most methods ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/6/S08
更新日期:2008-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/32/10/002
更新日期:2011-10-01 00:00:00
abstract:OBJECTIVE:Bioimpedance has been used to investigate changes in electrical parameters during ischemia in various tissues. The small intestine is a multi-layered structure, with several distinct tissue types, and ischemia related changes occur at different times in the different intestinal layers. When investigating how ...
journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2017-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/10/006
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/11/2319
更新日期:2014-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/10/014
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doi:10.1088/1361-6579/ab525c
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更新日期:2018-07-16 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aaa455
更新日期:2018-02-26 00:00:00
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journal_title:Physiological measurement
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更新日期:2020-10-06 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/6/009
更新日期:2010-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aa8a1a
更新日期:2017-09-21 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/5/763
更新日期:2014-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac553
更新日期:2018-06-19 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/19/1/008
更新日期:1998-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/28/2/007
更新日期:2007-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba80f
更新日期:2020-09-04 00:00:00
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doi:10.1088/0967-3334/30/10/002
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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journal_title:Physiological measurement
pub_type: 杂志文章
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journal_title:Physiological measurement
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更新日期:2006-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/19/2/013
更新日期:1998-05-01 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aaa749
更新日期:2018-03-23 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/8/001
更新日期:2007-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2005-12-01 00:00:00
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pub_type: 杂志文章
doi:10.1088/0967-3334/22/4/401
更新日期:2001-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1088/0967-3334/36/10/2159
更新日期:2015-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/7/S19
更新日期:2007-07-01 00:00:00