FREE WATER IN BEAN SEEDS: THE IMBIBITION PROCESS ACCORDING TO THE MAGNETIC RESONANCE MICROTOMOGRAPHY DATA

Holzforschung ◽  
2020 ◽  
Vol 74 (11) ◽  
pp. 1021-1032 ◽  
Author(s):  
Sami Hiltunen ◽  
Arttu Mankinen ◽  
Muhammad Asadullah Javed ◽  
Susanna Ahola ◽  
Martti Venäläinen ◽  
...  

AbstractWood decay is an economically significant process, as it is one of the major causes of wood deterioration in buildings. In this study, the decay process of Scots pine (Pinus sylvestris) samples caused by cellar fungus (Coniophora puteana) was followed by nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) methods. Altogether, 30 wood sample pieces were exposed to fungus for 10 weeks. Based on the decrease of the dry mass, the samples were categorized into three classes: decomposed (mass decrease 50–70%), slightly decomposed (10–50%), and nondecomposed (<10%). MRI made it possible to identify the active regions of fungus inside the wood samples based on the signal of free water brought by the fungus and arisen from the decomposition of wood carbohydrates. MRI implies that free water is not only created by the decay process, but fungal hyphae also transports a significant amount of water into the sample. Two-dimensional 1H T1-T2 relaxation correlation NMR measurements provided detailed information about the changes in the microstructure of wood due to fungal decomposition. Overall, this study paves the way for noninvasive NMR and MRI detection of fungal decay at early stages as well as the related structural changes.


2021 ◽  
Vol 22 (10) ◽  
pp. 5216
Author(s):  
Koji Kamagata ◽  
Christina Andica ◽  
Ayumi Kato ◽  
Yuya Saito ◽  
Wataru Uchida ◽  
...  

There has been an increasing prevalence of neurodegenerative diseases with the rapid increase in aging societies worldwide. Biomarkers that can be used to detect pathological changes before the development of severe neuronal loss and consequently facilitate early intervention with disease-modifying therapeutic modalities are therefore urgently needed. Diffusion magnetic resonance imaging (MRI) is a promising tool that can be used to infer microstructural characteristics of the brain, such as microstructural integrity and complexity, as well as axonal density, order, and myelination, through the utilization of water molecules that are diffused within the tissue, with displacement at the micron scale. Diffusion tensor imaging is the most commonly used diffusion MRI technique to assess the pathophysiology of neurodegenerative diseases. However, diffusion tensor imaging has several limitations, and new technologies, including neurite orientation dispersion and density imaging, diffusion kurtosis imaging, and free-water imaging, have been recently developed as approaches to overcome these constraints. This review provides an overview of these technologies and their potential as biomarkers for the early diagnosis and disease progression of major neurodegenerative diseases.


Neurosurgery ◽  
2021 ◽  
Author(s):  
Fraser Henderson Jr ◽  
Drew Parker ◽  
Anupa A Vijayakumari ◽  
Mark Elliott ◽  
Timothy Lucas ◽  
...  

Abstract BACKGROUND A limitation of diffusion tensor imaging (DTI)-based tractography is peritumoral edema that confounds traditional diffusion-based magnetic resonance metrics. OBJECTIVE To augment fiber-tracking through peritumoral regions by performing novel edema correction on clinically feasible DTI acquisitions and assess the accuracy of the fiber-tracks using intraoperative stimulation mapping (ISM), task-based functional magnetic resonance imaging (fMRI) activation maps, and postoperative follow-up as reference standards. METHODS Edema correction, using our bi-compartment free water modeling algorithm (FERNET), was performed on clinically acquired DTI data from a cohort of 10 patients presenting with suspected high-grade glioma and peritumoral edema in proximity to and/or infiltrating language or motor pathways. Deterministic fiber-tracking was then performed on the corrected and uncorrected DTI to identify tracts pertaining to the eloquent region involved (language or motor). Tracking results were compared visually and quantitatively using mean fiber count, voxel count, and mean fiber length. The tracts through the edematous region were verified based on overlay with the corresponding motor or language task-based fMRI activation maps and intraoperative ISM points, as well as at time points after surgery when peritumoral edema had subsided. RESULTS Volume and number of fibers increased with application of edema correction; concordantly, mean fractional anisotropy decreased. Overlay with functional activation maps and ISM-verified eloquence of the increased fibers. Comparison with postsurgical follow-up scans with lower edema further confirmed the accuracy of the tracts. CONCLUSION This method of edema correction can be applied to standard clinical DTI to improve visualization of motor and language tracts in patients with glioma-associated peritumoral edema.


Holzforschung ◽  
2017 ◽  
Vol 71 (11) ◽  
pp. 881-887 ◽  
Author(s):  
Xinyu Li ◽  
Yulei Gao ◽  
Minghui Zhang ◽  
Ximing Wang ◽  
Xinyue Wei

AbstractThe migration of bound water and free water has been investigated during microwave drying of wood by the time domain nuclear magnetic resonance (TD-NMR) technique. Both the heartwood (hW) and sapwood (sW) of Beijing poplar (Populus beijingensisW. Y. Hsu) and Qingpi poplar (Populus platyphyllaT. Y. Sun) were studied. The microwave drying is characterized by a fast drying rate, and there is a linear relation between moisture content (MC) and microwave drying time (t). The drying rate of free water is about 2.7 times more rapid than that of bound water. The spin-spin relaxation time (T2) revealed that most of the water was free water situated in smaller pores. The irregular T2 signal amplitudes of free water in hWs indicated that fractional water in smaller pores was transferred into bigger pores during drying.


1994 ◽  
Vol 267 (4) ◽  
pp. R1078-R1088 ◽  
Author(s):  
B. Rubinsky ◽  
J. S. Hong ◽  
K. B. Storey

Two visual techniques were used to analyze the patterns of natural freezing and thawing in freeze-tolerant hatchling painted turtles Chrysemys picta marginata. Directional solidification plus light microscopy of liver, heart, and skeletal muscle slices was used to compare freezing at -4 degrees C (a survivable temperature in vivo) and -20 degrees C (not survivable). At -4 degrees C tissues showed large amounts of ice in expanded extracellular and vascular spaces, occupying 36% (liver) and 61% (muscle) of total tissue volume. Cells at -4 degrees C were shrunken, but intracellular water remained; at -20 degrees C, however, cells showed little evidence of free water. Liver micrographs showed novel spherical shells of water associated with intracellular particles (apparently glycogen granules) suggesting that a noncolligative method of cell water retention was employed. Proton magnetic resonance imaging was used for noninvasive analysis of freezing and thawing in the intact animal. Images showed that freezing propagated in a directional manner through the body with ice formed first in extraorgan spaces (e.g., abdominal cavity, brain ventricles). However, thawing occurred uniformly throughout the body core, and organs melted more rapidly than the extraorgan ice surrounding them.


2020 ◽  
Vol 225 (1) ◽  
pp. 427-439 ◽  
Author(s):  
Marcelo Febo ◽  
Pablo D. Perez ◽  
Carolina Ceballos-Diaz ◽  
Luis M. Colon-Perez ◽  
Huadong Zeng ◽  
...  

Holzforschung ◽  
2017 ◽  
Vol 71 (1) ◽  
pp. 77-90 ◽  
Author(s):  
Maria Fredriksson ◽  
Lisbeth Garbrecht Thygesen

Abstract Low-field nuclear magnetic resonance (LFNMR) relaxometry was applied to determine the spin-spin relaxation time (T2) of water-saturated Norway spruce (Picea abies (L.) Karst.) specimens cut from mature sapwood (sW) and mature and juvenile heartwood (hW), where earlywood (EW) and latewood (LW) were separated. In combination with quantitative wood anatomy data focusing on the void volumes in various morphological regions, the NMR data served for a more reliable assignment of free-water populations found in water-saturated solid wood. Two free-water populations were identified within most sample types. One was assigned to water in the tracheid lumen and the other to water inside bordered pits. Whether water in the ray cell lumina was included in one or the other of these two populations depends on the curve-fit method applied (continuous or discrete). In addition, T2 differences between the different tissue types were studied and, for comparison, sorption isotherms were measured by means of a sorption balance. There was a significant difference between EW and LW as well as between juvenile wood and mature wood in terms of T2 related to the cell wall water. However, no differences were seen between the sorption isotherms, which indicates that the observed T2 differences were not due to differences in cell wall moisture content (MC).


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