Scalp attached tangential magnetoencephalography using tunnel magneto-resistive sensors

Author(s):  
Akitake Kanno ◽  
Nobukazu Nakasato ◽  
Mikihiko Oogane ◽  
Kosuke Fujiwara ◽  
Takafumi Nakano ◽  
...  

Abstract Non-invasive human brain functional imaging with millisecond resolution can be achieved only with magnetoencephalography (MEG) and electroencephalography (EEG). MEG has better spatial resolution than EEG because signal distortion due to inhomogeneous head conductivity is negligible in MEG but serious in EEG. However, this advantage has been practically limited by the necessary setback distances between the sensors and scalp, because the Dewar vessel containing liquid helium for superconducting sensors requires a thick vacuum wall. Latest developments of high critical temperature (high-Tc) superconducting or optically pumped magnetometers have not allowed scalp-attached MEG due to cold or hot temperatures at the sensing point, respectively. Here we applied tunnel magneto-resistive (TMR) sensors that operate at room temperature. Improvement of TMR sensitivity with magnetic flux concentrators enabled scalp-attached and scalp-tangential MEG to target the largest signal component produced by the neural current below. In a healthy subject, our single-channel TMR-MEG system clearly demonstrated the N20m, the initial cortical component of the somatosensory evoked response after median nerve stimulation. Multisite measurement confirmed a spatially and temporally steep peak of N20m, immediately above the source at a latency around 20 ms, indicating a new approach to non-invasive functional brain imaging with millimeter and millisecond resolutions.

Author(s):  
Neha Mehta ◽  
Svav Prasad ◽  
Leena Arya

Ultrasound imaging is one of the non-invasive imaging, that diagnoses the disease inside a human body and there are numerous ultrasonic devices being used frequently. Entropy as a well known statistical measure of uncertainty has a considerable impact on the medical images. A procedure for minimizing the entropy with respect to the region of interest is demonstrated. This new approach has shown the experiments using Extracted Region Of Interest Based Sharpened image, called as (EROIS) image based on Minimax entropy principle and various filters. In this turn, the approach also validates the versatility of the entropy concept. Experiments have been performed practically on the real-time ultrasound images collected from ultrasound centers and have shown a significant performance. The present approach has been validated with showing results over ultrasound images of the Human Gallbladder.


1993 ◽  
Vol 22 (5) ◽  
pp. 479-484 ◽  
Author(s):  
R. D. Feldman ◽  
T. D. Harris ◽  
J. E. Zucker ◽  
D. Lee ◽  
R. F. Austin ◽  
...  

Pancreatology ◽  
2021 ◽  
Vol 21 ◽  
pp. S89-S90
Author(s):  
K. Lesko ◽  
G. Varvanina ◽  
D. Bordin ◽  
E. Dubtsova ◽  
M. Malykh ◽  
...  

2004 ◽  
Vol 08 (06) ◽  
pp. 297-308

Ai Scientific Awarded R&D Start Grant. CSIRO Drug Effective against Bird Flu. AustCancer Commences Anti-cancer Vaccine Phase II Trial. New Approach against Cancer. Non-invasive Cancer Test. China’s Chemical Pharmaceutical Sector Q1 2003 Performance. International Generic Companies Target India’s Manufacture Infrastructure. Cardinal Health Sets up Regional Office in Singapore. BRV Enters Agreement with Genedata.


2021 ◽  
Author(s):  
Natalia Browarska ◽  
Jaroslaw Zygarlicki ◽  
Mariusz Pelc ◽  
Michal Niemczynowicz ◽  
Malgorzata Zygarlicka ◽  
...  

2021 ◽  
Vol 21 ◽  
Author(s):  
Sara Memarpour ◽  
Ghazaleh Khalili-Tanha ◽  
Awa Alizadeh Ghannad ◽  
Masoud Sharifian Razavi ◽  
Mona Joudi ◽  
...  

: Gastrointestinal (GI) cancer is one of the most common cancers globally. Genetic and epigenetic mechanisms are involved in its pathogenesis. The conventional methods for diagnosis and screening for GI cancers are often invasive and have other limitations. In the era of personalized medicine, a novel non-invasive approach called liquid biopsy has been introduced for the detection and management of GI cancers, which focuses on the analysis of circulating tumor cells (CTCs) and circulating cell-free tumor DNA (ctDNA). Several studies have shown that this new approach allows for an improved understanding of GI tumor biology and will lead to an improvement in clinical management. The aim of the current review is to explore the clinical applications of CTCs and ctDNA in patients with GI cancer.


Author(s):  
Christopher A. Lerch ◽  
Richard H. Lyon

Abstract A method termed harmonic tracking is developed to recover time dependent gear motion from machine casing vibration. The harmonic tracking method uses short-time spectral generation and a subsequent set of algorithms to locate and track gear meshing frequencies as functions of time. The meshing frequencies are then integrated with respect to time to obtain the rotation of individual gears. More specifically, spectral generation is performed using the discrete Fourier transform, and the locating and tracking algorithms involve locating tones in each short-time spectrum and tracking them through successive spectra to recover gear meshing harmonics. The harmonic tracking method is found to be more robust than demodulation-based methods in the presence of measurement noise and signal distortion from the structural transfer function between gears and the casing. The harmonic tracking method is tested, both through simulation and experiments involving motor-operated valves (MOV’s) as part of the development of a diagnostic system for MOV’s. In all cases, the harmonic tracking method is found to recover gear motion with sufficient accuracy to perform diagnostics. The harmonic tracking method should be generally applicable to situations in which a non-invasive technique is required for determining the time-dependent angular speeds and displacements of gearbox input, intermediary, and output shafts.


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