Approximate Subject Specific Pseudo MRI from an Available MRI Dataset for MEG Source Imaging

Gohel, Bakul,Lim, Sanghyun,Kim, Min-Young,Kwon, Hyukchan,Kim, Kiwoong Frontiers Media S.A. 2017 Frontiers in neuroinformatics Vol.11 No.-

<P>Computation of headmodel and sourcemodel from the subject's MRI scan is an essential step for source localization of magnetoencephalography (MEG) (or EEG) sensor signals. In the absence of a real MRI scan, pseudo MRI (i.e., associated headmodel and sourcemodel) is often approximated from an available standard MRI template or pool of MRI scans considering the subject's digitized head surface. In the present study, we approximated two types of pseudo MRI (i.e., associated headmodel and sourcemodel) using an available pool of MRI scans with the focus on MEG source imaging. The first was the first rank pseudo MRI; that is, the MRI scan in the dataset having the lowest objective registration error (ORE) after being registered (rigid body transformation with isotropic scaling) to the subject's digitized head surface. The second was the averaged rank pseudo MRI that is generated by averaging of headmodels and sourcemodels from multiple MRI scans respectively, after being registered to the subject's digitized head surface. Subject level analysis showed that the mean upper bound of source location error for the approximated sourcemodel in reference to the real one was 10 ± 3 mm for the averaged rank pseudo MRI, which was significantly lower than the first rank pseudo MRI approach. Functional group source response in the brain to visual stimulation in the form of event-related power (ERP) at the time latency of peak amplitude showed noticeably identical source distribution for first rank pseudo MRI, averaged rank pseudo MRI, and real MRI. The source localization error for functional peak response was significantly lower for averaged rank pseudo MRI compared to first rank pseudo MRI. We conclude that it is feasible to use approximated pseudo MRI, particularly the averaged rank pseudo MRI, as a substitute for real MRI without losing the generality of the functional group source response.</P>

Dynamic pattern decoding of source-reconstructed MEG or EEG data: Perspective of multivariate pattern analysis and signal leakage

Gohel, Bakul,Lim, Sanghyun,Kim, Min-Young,Kwon, Hyukchan,Kim, Kiwoong Elsevier 2018 Computers in biology and medicine Vol.93 No.-

<P><B>Abstract</B></P> <P>Recently, an increasing number of studies have employed multivariate pattern analysis (MVPA) rather than univariate analysis for the dynamic pattern decoding of event-related responses recorded with a MEG/EEG sensor. The use of the MVPA approach for source-reconstructed MEG/EEG data is uncommon. For these data, we need to consider the source orientation information and the signal leakage among brain regions. In the present study, we evaluate the perspective of the MVPA approach in the context of source orientation information and signal leakage in source-reconstructed MEG data. We perform face vs. tool object category decoding (FvsT-OCD) of event-related responses from single or multiple voxels from a brain region using a univariate analysis approach and/or the MVPA approach. We also propose and perform symmetric signal leakage correction of source-reconstructed data using an independent component analysis-based approach. FvsT-OCD using single voxel information shows higher sensitivity for the MVPA approach than univariate analysis, as the MVPA approach efficiently utilizes information on all three dipole orientations and is less affected by inter-subject variability. The MVPA approach shows higher sensitivity for FvsT-OCD when considering information from multiple voxels than for a single voxel in a brain region. This finding suggests that the MVPA approach captures the latent multivoxel distributed pattern. However, the results may be partly or entirely attributable to signal leakage between brain regions, as the sensitivity is substantially reduced after signal leakage correction. A consideration of signal leakage is therefore essential during the evaluation of MVPA outcomes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The multivariate pattern analysis (MVPA) is increasingly used in cognitive studies. </LI> <LI> Use of the MVPA approach is uncommon for source-reconstructed M/EEG data analysis. </LI> <LI> The study takes account of the source orientation and signal leakage issue. </LI> <LI> The MVPA method can effectively use information from all three source orientations. </LI> <LI> Signal leakage and its correction significantly influence the MVPA outcomes. </LI> </UL> </P>

Notes : Statistical Optimization of Chitinase Production by Pantoea dispersa to Enhance Degradation of Crustacean Chitin Waste

( Gohel Vipul ),( Derick Jiwan ),( Pranav Vyas ),( H. S. Chhatpar ) 한국미생물 · 생명공학회 2005 Journal of microbiology and biotechnology Vol.15 No.1

Predictive maintenance architecture development for nuclear infrastructure using machine learning

Gohel Hardik A.,Upadhyay Himanshu,Lagos Leonel,Cooper Kevin,Sanzetenea Andrew 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.7

Nuclear infrastructure systems play an important role in national security. The functions and missions of nuclear infrastructure systems are vital to government, businesses, society and citizen's lives. It is crucial to design nuclear infrastructure for scalability, reliability and robustness. To do this, we can use machine learning, which is a state of the art technology used in various fields ranging from voice recognition, Internet of Things (IoT) device management and autonomous vehicles. In this paper, we propose to design and develop a machine learning algorithm to perform predictive maintenance of nuclear infrastructure. Support vector machine and logistic regression algorithms will be used to perform the prediction. These machine learning techniques have been used to explore and compare rare events that could occur in nuclear infrastructure. As per our literature review, support vector machines provide better performance metrics. In this paper, we have performed parameter optimization for both algorithms mentioned. Existing research has been done in conditions with a great volume of data, but this paper presents a novel approach to correlate nuclear infrastructure data samples where the density of probability is very low. This paper also identifies the respective motivations and distinguishes between benefits and drawbacks of the selected machine learning algorithms.

Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

J. E. Kim,Bakul Gohel,K. Kim,H. Kwon,Kyung-min An 한국초전도저온학회 (구 한국초전도저온공학회) 2015 한국초전도저온공학회논문지 Vol.17 No.4

Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

Kim, J.E.,Gohel, Bakul,Kim, K.,Kwon, H.,An, Kyung-min The Korea Institute of Applied Superconductivity a 2015 한국초전도저온공학회논문지 Vol.17 No.4

Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8-13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

Formulation and characterization of ternary complex of sublingual film of buspirone hydrochloride

Renuka Mishra,Arun Sharma,Tejal Mehta,Mukesh Gohel 한국약제학회 2015 Journal of Pharmaceutical Investigation Vol.45 No.4

Taste masked sublingual film of buspirone hydrochloride (BH) was developed with the objectives of taste masking, fast disintegration, increased dissolution and better patient compliance. The film was formulated using Polyox WSRN-10, polyvinyl pyrolidone (PVP) K-30 and propylene glycol as a plasticizer. Taste masking was obtained by ternary complexation between BH, β-cyclodextrin and PVP K-30. Optimized batch contained 3 % w/v of Polyox WSR N-10, 2 % w/v PVP K-30 and propylene glycol (20 % weight of Polyox WSR N-10). The optimized formulation also contained BH: β-CD (1:1.5 molar ratio), BH: sucralose (1:0.5 ratio) and 0.15 ml orange flavour. This batch was evaluated for % elongation, tensile strength, in vitro disintegration time and in vitro dissolution studies. In-vitro permeation studies employing rabbit sublingual mucosa, indicated higher drug permeability at the ventral surface than at the bottom surface of the mouth. In-vivo absorption studies in rabbits revealed that 50.27 ± 5.24 % of BH was absorbed sublingually from film within 5 min. The kinetics of in vivo drug absorbed from sublingual film in human volunteers indicated that there is no significant difference between ex vivo and in vivo data obtained for the drug absorption. The formulation, subjected to stability studies at 25 ˚C/60 % RH for 2 months, showed good stability indicating suitable packaging and storage conditions.

Momentary level of slow default mode network activity is associated with distinct propagation and connectivity patterns in the anesthetized mouse cortex

Kang, Minseok,Lee, Young-Beom,Gohel, Bakul,Yoo, Kwangsun,Lee, Peter,Chung, Jinyong,Jeong, Yong American Physiological Society 2018 journal of neurophysiology Vol.119 No.2

Effects of Fabric Surface Energy on Human Thermophysiological Responses during Exercise and Recovery

Zhou, L.Y.,Li, Y.,Chung, J.,Tokura, H.,Gohel, M.D.I.,Kwok, Y.L.,Feng, X.W. The Korean Fiber Society 2007 Fibers and polymers Vol.8 No.3

The present paper reports a study on influences of fabric surface energy of cotton and polyester garments on clothing microclimates and human thermophysiological responses during intermittent exercise and recovery. Eight healthy males wearing the garments prepared performed exercises and rest according to the following protocol: rest for 30 min, run on treadmill for total 60 min of three sessions with different intensity and duration, and then sit quietly for 30 min for recovery, all at $30^{\circ}C$ and relative humidity of 30 %, while the microclimate humidity ($H_{mc}$) and temperature ($T_{mc}$), the clothing outside surface humidity ($H_{co}$) and temperature ($T_{co}$), the skin temperatures and ear canal temperature ($T_{ear_canal})$ were measured. The garments are made of: (a) hydrophilic and hydrophobic cotton knitted fabrics, and (b) hydrophilic and hydrophobic polyester knitted fabrics. During and after exercise, for cotton, hydrophilic garment resulted in significant lower ${\Delta}H_{mc}$, ${\Delta}H_{co}$, ${\Delta}T_{mc}$, during recovery, higher ${\Delta}{\bar{T}}_{sk}$, lower ${\Delta}T_{ear_canal}$ and ${\Delta}T_{forehead}$. For polyester, hydrophilic garment resulted in significantly lower ${\Delta}H_{co}$, ${\Delta}T_{co}$, higher ${\Delta}T_{forehead}$, during E1, E2 and recovery session but lower during E3. In summary, surface energy of cotton garments had significant influences on human thermophysiological responses during exercise and recovery, and hydrophilic cotton garment was better than hydrophobic one to reduce heat stress. Surface energy of polyester garments had influences of lower significance, and hydrophilic garment appeared better than hydrophobic garment.

Energy Characteristics and Failure Mechanisms for Textile Spread Tow Thin Ply Thermoplastic Composites under Low-velocity Impact

Somen K. Bhudolia,Sunil C. Joshi,Anthony Bert,Goram R. Gohel,Makam Raama 한국섬유공학회 2019 Fibers and polymers Vol.20 No.8

Carbon composites are deemed suitable for components with complex geometries which require high impactresistance. The broad range of industrial applications requires composite structures to be lighter and not to compromise withtheir mechanical performance. Non-crimp fabrics with lower fibre areal weight (FAW) are the class of reinforcement materialwhich will only bring the advantages of better mechanical properties but will also offer more longevity to the structures andreduced maintenance costs. This research aims at investigating the low-velocity impact performance of textile spread towthin ply (100 gsm) composites with an aim to study the load bearing capability, deflection characteristics and energycharacteristics. The results are compared with the baseline thick (200 gsm) fibre reinforced composites. There was 19.2 %,16.6 %, and 6.57 % higher peak load for spread tow thin ply composites when compared to thick ply composites at 25 J, 42 J,and 52 J impact energies respectively. Significantly lower residual deflection (40 % to 76 %) and higher major damageenergy (20 % to 33 %) were observed for spread tow thin ply laminates compared to the thick ply variant at different impactenergies. At 42 J and 52 J impact energies, the damage index (DI) was 2 times and 4 times higher for Thick ply laminateshighlighting extensive damage, which is also observed with detailed failure mechanisms study.