Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 23 for “"Apparent diffusion coefficient"”.
-
The “Apparent” Diffusion Coefficient of Electrons Through a Nafion Membrane
… into account rotation rate dependence and the apparent diffusion of electrons through the membrane.</p>
-
The diffusion of water and aviation fuel in polysulphide sealants
The diffusion and permeation of aviation fuel (Avtur) and water in commercial and 'model' polysulphide sealants have been studied using simple gravimetric techniques. For Avtur, the mass uptake behaviour is explicable in terms of normal, Fickian diffusion, and the diffusion coefficient determined …
-
Chloride penetration in concrete: evaluation of rapid conductivity methods and development of a service life prediction model for marine conditions
… are rapid alternatives to the time-consuming diffusion tests for the characterisation and quality control of concrete mixtures. To estimate the long-term behaviour of a concrete mixture in marine conditions, however, and propose a proper combination of adequate cover depth and concrete …
-
A Model for Studying Vasogenic Brain Edema
… staining verified that VE has formed. However, apparent diffusion coefficient (ADC) and histological examination revealed also that some possible cytotoxic edema formed.This model provides a reproducible technique for generating a large area of edema for CED study. Further studies with lower …
-
A numerical study of the effects of inhomogeneous media in diffusion weighted imaging
Diffusion Weighted Imaging (DWI) -a common Magnetic Resonance Imaging (MRI) technique - is used to infer material properties of tissues from the average diffusion of water molecules over brief time intervals. In particular, the Apparent Diffusion Coefficient (ADC), a measure of the magnitude of …
-
Chloride Penetration Resistance and link to Service Life Design of Virginia Bridge Decks
… chloride concentration and chloride migration coefficient. The service life estimations for a case study bridge in Virginia from three service life models were compared. The first model is based on the fib Bulletin 34 Model Code for Service Life Design, the second is a finite element solution …
-
Quantification of Pulmonary Ventilation using Hyperpolarized 3He Magnetic Resonance Imaging
… structural measurements of disease (using the apparent diffusion coefficient (ADC) derived from diffusion-weighted images) may provide a new method for phenotyping this smoking-related lung disease.
-
A Lattice Boltzmann method model of diffusion-weighted magnetic resonance imaging in skeletal muscle
… protocols we can investigate non-invasively diffusion phenomena within skeletal muscle. This project focuses on the numerical study of the effect of microstructure on the effective diffusion coefficient via a Lattice Boltzmann model (LBM). Specifically, we aim to characterize how variations …
-
Impact of Specification Changes on Chloride Induced Corrosion Service Life of Virginia Bridge Decks
… and simple bootstrap. Emphasis was placed on the diffusion portion of the diffusion-cracking model, but advances can be readily included for the time for corrosion deterioration after corrosion initiation. Data collected from ten bridge decks built in Virginia between 1981 and 1994 was used to …
-
Detection of prostate cancer using multi-parametric magnetic resonance
… T2-weighted, T2-mapping, and Line Scan Diffusion lmaging(LSDI). From these MR sequences, 4 sets of image intensities were obtained: T2-weighted(T2W) from T2-weighted imaging, Apparent Diffusion Coefficient(ADC) from LSDI, and Proton Density (PD) and T2 (T2Map) from T2-mapping imaging. …
-
Characterization of Normal Development and Injury in the Premature Baboon Brain
… magnetic resonance imaging: MRI) and diffusion tensor imaging: DTI) was obtained on fixed brains. In addition, histopathology was obtained. Analysis of this model led to the following conclusions.: 1) MRI/DTI findings during brain maturation closely paralleled those from live premature …
-
MRI at 3 T of brain functions and fibre tracts adjacent to intracranial tumors
… variability (Paper 3); to determine whether the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) can distinguish tumor-infiltrated edema of gliomas from pure edema of meningiomas and metastases (Paper 4). Results: Strict somatotopic organisation in the primary sensory cortex …
-
Investigation of Microstructure of Uterine Fibroids in Magnetic Resonance guided High Intensity Focused Ultrasound Therapy
… approaches to assess tissue microstructure (diffusion and perfusion) to distinguish treatable and non-treatable fibroids. It is found that with T2-correction, f (blood volume ratio in IVIM) is different for different types of fibroids. (3) Three potential non-contrast based methods to …
-
Functional Magnetic Resonance Imaging of Breast Cancer
… thesis compares the diagnostic performance of diffusion-weighted imaging (DWI) models in the breast using a systematic review and meta-analysis. Advanced diffusion models have been proposed that may improve the performance of standard DWI using the apparent diffusion coefficient (ADC) to …
-
Quantifying, Understanding and Predicting Differences Between Planned and Delivered Dose to Organs at Risk in Head & Neck Cancer Patients Undergoing Radical Radiotherapy to Promote Intelligently Targeted Adaptive Radiotherapy
… Changes in salivary gland volumes and relative apparent diffusion coefficient (ADC) values were measured and related to toxicity events. Results: Spinal cord dose differences were small, and not predicted by weight loss or shape change. Mean DA to all other OARs was higher than DP; factors …
-
Integration of Biomedical Imaging and Translational Approaches For Management of Head and Neck Cancer
… Our findings showed that delta changes of apparent diffusion coefficient parameters derived from diffusion-weighted images at mid-RT can be used to predict local recurrence and recurrence free-survival. We also showed that K<sup>trans</sup> and V<sub>e</sub> vascular parameters derived from …
-
Novel approaches to MRI of glioma
… as well as changes in the tissue microstructure. Diffusion-Weighted Imaging (DWI) and the apparent diffusion coefficient (ADC), have been extensively studied as potential imaging biomarkers for cellularity and tissue architecture. However, several studies have shown partial overlap in the measured …
-
Phase Behaviour and Mass Transfer of Solvent(s)-CO2-Heavy Oil Systems Under Reservoir Conditions
… methods have been performed to determine the diffusion coefficient of each component in the solvent(s)-CO2 mixture or the apparent diffusion coefficient of the mixture in heavy oil. It is found that the gas-phase solvent fraction decreases as diffusion proceeds, while the gas-phase CO2 …
-
Dynamic Contrast-Enhanced MRI and Diffusion-Weighted MRI for the Diagnosis of Bladder Cancer
… 3T dynamic contrast-enhanced MRI (DCE-MRI) and diffusion-weighted MRI (DWI) to improve the detection and staging and to enable the prediction of chemotherapeutic response in bladder cancer. A total of fifty-three patients were enrolled in the study. Different inclusion criteria were established …
Page 1 of 2