Changes in Soil Water Content Resulting from Ricinus Root Uptake Monitored by Magnetic Resonance Imaging

2008 ◽  
Vol 7 (3) ◽  
pp. 1010-1017 ◽  
Author(s):  
A. Pohlmeier ◽  
A. Oros-Peusquens ◽  
M. Javaux ◽  
M. I. Menzel ◽  
J. Vanderborght ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Root Uptake ◽  
Resonance Imaging

scholarly journals Magnetic Resonance Imaging of Water Content and Flow Processes in Natural Soils by Pulse Sequences with Ultrashort Detection

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5130
Author(s):  
Sabina Haber-Pohlmeier ◽  
David Caterina ◽  
Bernhard Blümich ◽  
Andreas Pohlmeier
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Content ◽  
Soil Water ◽  
Spin Echo ◽  
Pulse Sequences ◽  
Relaxation Times ◽  
Natural Soil ◽  
Resonance Imaging ◽  
Transverse Relaxation

Magnetic resonance imaging is a valuable tool for three-dimensional mapping of soil water processes due to its sensitivity to the substance of interest: water. Since conventional gradient- or spin-echo based pulse sequences do not detect rapidly relaxing fractions of water in natural porous media with transverse relaxation times in the millisecond range, pulse sequences with ultrafast detection open a way out. In this work, we compare a spin-echo multislice pulse sequence with ultrashort (UTE) and zero-TE (ZTE) sequences for their suitability to map water content and its changes in 3D in natural soil materials. Longitudinal and transverse relaxation times were found in the ranges around 80 ms and 1 to 50 ms, respectively, so that the spin echo sequence misses larger fractions of water. In contrast, ZTE and UTE could detect all water, if the excitation and detection bandwidths were set sufficiently broad. More precisely, with ZTE we could map water contents down to 0.1 cm3/cm3. Finally, we employed ZTE to monitor the development of film flow in a natural soil core with high temporal resolution. This opens the route for further quantitative imaging of soil water processes.

Magnetic Resonance Imaging Spatial and Time Study of Lung Water Content in Newborn Lamb: Methods and Preliminary Results

2008 ◽  
Vol 43 (6) ◽  
pp. 470-480 ◽  
Author(s):  
Romain Viard ◽  
Pierre Tourneux ◽  
Laurent Storme ◽  
Julie-Marie Girard ◽  
Nacim Betrouni ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Content ◽  
Time Study ◽  
Resonance Imaging ◽  
Lung Water ◽  
Newborn Lamb ◽  
Preliminary Results ◽  
Lung Water Content

scholarly journals Increased fasting small‐bowel water content in untreated coeliac disease and scleroderma as assessed by magnetic resonance imaging

2019 ◽  
Vol 7 (10) ◽  
pp. 1353-1360 ◽  
Author(s):  
Ching Lam ◽  
David S Sanders ◽  
Peter Lanyon ◽  
Klara Garsed ◽  
Stephen Foley ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Small Bowel ◽  
Coeliac Disease ◽  
Water Content ◽  
Resonance Imaging

scholarly journals An Absolute Measurement of Brain Water Content Using Magnetic Resonance Imaging in Two Focal Cerebral Ischemic Rat Models

2000 ◽  
Vol 20 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Weili Lin ◽  
Ramesh Venkatesan ◽  
Kilichan Gurleyik ◽  
Yong Y. He ◽  
William J. Powers ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Content ◽  
Spin Density ◽  
Absolute Measurement ◽  
Brain Water Content ◽  
Resonance Imaging ◽  
Regional Brain ◽  
Brain Water

Magnetic resonance imaging (MRI) was utilized to obtain absolute estimates of regional brain water content (W), and results were compared with those obtained with conventional wet/dry measurements. In total, 31 male Long-Evans rats were studied and divided into two groups based on the surgical procedures used to induce cerebral focal ischemia: suture (n = 18) and three-vessel ligation (TVL; n = 13) groups. Both relative spin density and T1 were extracted from the acquired MR images. After correcting for radiofrequency field inhomogeneities, T2* signal decay, and temperature effects, in vivo regional brain water content, in absolute terms, was obtained by normalizing the measured relative brain spin density of animals to that of a water phantom. A highly linear relationship between MR-estimated brain water content based on the normalized spin density and wet/dry measurements was obtained with slopes of 0.989 and 0.986 for the suture ( r = 0.79) and TVL ( r = 0.83) groups, respectively. Except for the normal subcortex of the TVL group ( P < 0.02) and the normal hemisphere of the suture group ( P < 0.003), no significant differences were observed between MR-estimated and wet/dry measurements of brain water content. In addition, a highly linear relationship between MR-measured R1 (= 1/T1) and 1/W of wet/dry measurements was obtained. However, slopes of the linear regression lines in the two groups were significantly different ( P < 0.02), indicating that different R1 values were associated with the same water content depending on the model. These results show that an absolute measurement of in vivo regional brain water content can be obtained with MRI and potentially serves as a noninvasive means to monitor different therapeutic interventions for the management of brain edema subsequent to stroke and head trauma.

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