Validation of deep learning techniques for quality augmentation in diffusion MRI for clinical studies

The objective of this study is to evaluate the efficacy of deep learning (DL) techniques in improving the quality of diffusion MRI (dMRI) data in clinical applications. The study aims to determine whether the use of artificial intelligence (AI) methods in medical images may result in the loss of critical clinical information and/or the appearance of false information. To assess this, the focus was on the angular resolution of dMRI and a clinical trial was conducted on migraine, specifically between episodic and chronic migraine patients. The number of gradient directions had an impact on white matter analysis results, with statistically significant differences between groups being drastically reduced when using 21 gradient directions instead of the original 61. Fourteen teams from different institutions were tasked to use DL to enhance three diffusion metrics (FA, AD and MD) calculated from data acquired with 21 gradient directions and a b-value of 1000 s/mm2. The goal was to produce results that were comparable to those calculated from 61 gradient directions. The results were evaluated using both standard image quality metrics and Tract-Based Spatial Statistics (TBSS) to compare episodic and chronic migraine patients. The study results suggest that while most DL techniques improved the ability to detect statistical differences between groups, they also led to an increase in false positive. The results showed that there was a constant growth rate of false positives linearly proportional to the new true positives, which highlights the risk of generalization of AI-based tasks when assessing diverse clinical cohorts and training using data from a single group. The methods also showed divergent performance when replicating the original distribution of the data and some exhibited significant bias. In conclusion, extreme caution should be exercised when using AI methods for harmonization or synthesis in clinical studies when processing heterogeneous data in clinical studies, as important information may be altered, even when global metrics such as structural similarity or peak signal-to-noise ratio appear to suggest otherwise

Fabrication of new high temperature Gd2O3-ZrO2 insulation coatings on Ag tapes by sol-gel technique for magnet technology

WOS: 000410723100013Cost-effective and easy-to-apply materials are necessary for magnet technologies. This research covers a fabrication development of high temperature insulation coatings for magnet technologies. With this context, gel coatings were successfully deposited on Ag tapes using sol-gel technique by preparing transparent solutions from Gd-and Zr-based precursor materials, methanol and glacial acetic acid, and subsequently 0, 5, 8, and 12 mol% Gd2O3ZrO2 coatings were heat treated at 300, 500, and 800 degrees C which respectively indicate drying, heat treatment, and annealing processes. Prior to coating process, Gd2O3 effect on thermal, structural and microstructural, and electrical properties were observed and extensively discussed in the present study. FTIR revealed that when increasing heat treatment temperature from 25 to 800 degrees C, the frequencies of OH, C-H, and C=O bands decreased. According to XRD results, Gd2O3 additive has a propensity to generate tetragonal ZrO2 and help to stabilize it. It was also observed that the regular surface morphology generally forms when Gd2O3 content increase in ZrO2 from0 to 12mol%. The film thicknesses increased from 0.5 to 1.8 m as a function of number of dipping. The porosities of the insulation coatings can be estimated to be in the range of 25 and 40 vol%. Besides, as insulative layers, Gd2O3 additive improved ZrO2 coatings. As a result, commercial Ag and AgMg sheathed Bi-2212 long length tapes can be insulated with pure ZrO2 and Gd2O3-ZrO2 coatings and then the coated tapes can be wound to fabricate an electromagnet

Fabrication of new high temperature Gd2O3-ZrO2 insulation coatings on Ag tapes by sol-gel technique for magnet technology

WOS: 000410723100013Cost-effective and easy-to-apply materials are necessary for magnet technologies. This research covers a fabrication development of high temperature insulation coatings for magnet technologies. With this context, gel coatings were successfully deposited on Ag tapes using sol-gel technique by preparing transparent solutions from Gd-and Zr-based precursor materials, methanol and glacial acetic acid, and subsequently 0, 5, 8, and 12 mol% Gd2O3ZrO2 coatings were heat treated at 300, 500, and 800 degrees C which respectively indicate drying, heat treatment, and annealing processes. Prior to coating process, Gd2O3 effect on thermal, structural and microstructural, and electrical properties were observed and extensively discussed in the present study. FTIR revealed that when increasing heat treatment temperature from 25 to 800 degrees C, the frequencies of OH, C-H, and C=O bands decreased. According to XRD results, Gd2O3 additive has a propensity to generate tetragonal ZrO2 and help to stabilize it. It was also observed that the regular surface morphology generally forms when Gd2O3 content increase in ZrO2 from0 to 12mol%. The film thicknesses increased from 0.5 to 1.8 m as a function of number of dipping. The porosities of the insulation coatings can be estimated to be in the range of 25 and 40 vol%. Besides, as insulative layers, Gd2O3 additive improved ZrO2 coatings. As a result, commercial Ag and AgMg sheathed Bi-2212 long length tapes can be insulated with pure ZrO2 and Gd2O3-ZrO2 coatings and then the coated tapes can be wound to fabricate an electromagnet