{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T02:13:17Z","timestamp":1775787197709,"version":"3.50.1"},"reference-count":19,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T00:00:00Z","timestamp":1726617600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["23K11789"],"award-info":[{"award-number":["23K11789"]}]},{"name":"JSPS KAKENHI","award":["23H05493"],"award-info":[{"award-number":["23H05493"]}]},{"name":"JSPS KAKENHI","award":["Q23L-01"],"award-info":[{"award-number":["Q23L-01"]}]},{"name":"Research Institute for Science and Technology of Tokyo Denki University","award":["23K11789"],"award-info":[{"award-number":["23K11789"]}]},{"name":"Research Institute for Science and Technology of Tokyo Denki University","award":["23H05493"],"award-info":[{"award-number":["23H05493"]}]},{"name":"Research Institute for Science and Technology of Tokyo Denki University","award":["Q23L-01"],"award-info":[{"award-number":["Q23L-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Magnetoencephalography (MEG) systems are advanced neuroimaging tools used to measure the magnetic fields produced by neuronal activity in the human brain. However, they require significant amounts of liquid helium to keep the superconducting quantum interference device (SQUID) sensors in a stable superconducting state. Additionally, MEG systems must be installed in a magnetically shielded room to minimize interference from external magnetic fields. We have developed an advanced MEG system that incorporates a superconducting magnetic shield and a zero-boil-off system. This system overcomes the typical limitations of traditional MEG systems, such as the frequent need for liquid helium refills and the spatial constraints imposed by magnetically shielded rooms. To validate the system, we conducted an evaluation using signal source estimation. This involved a phantom with 50 current sources of known location and magnitude under active zero-boil-off conditions. Our evaluations focused on the precision of the magnetic field distribution and the quantification of estimation errors. We achieved a consistent magnetic field distribution that matched the source current, maintaining an estimation error margin within 3.5 mm, regardless of the frequency of the signal source current. These findings affirm the practicality and efficacy of the system.<\/jats:p>","DOI":"10.3390\/s24186044","type":"journal-article","created":{"date-parts":[[2024,9,19]],"date-time":"2024-09-19T04:59:54Z","timestamp":1726721994000},"page":"6044","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Superconducting Self-Shielded and Zero-Boil-Off Magnetoencephalogram Systems: A Dry Phantom Evaluation"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5334-9300","authenticated-orcid":false,"given":"Keita","family":"Tanaka","sequence":"first","affiliation":[{"name":"Department of Science and Engineering, Tokyo Denki University, Saitama 350-0394, Japan"}]},{"given":"Akihiko","family":"Tsukahara","sequence":"additional","affiliation":[{"name":"Department of Science and Engineering, Tokyo Denki University, Saitama 350-0394, Japan"}]},{"given":"Hiroki","family":"Miyanaga","sequence":"additional","affiliation":[{"name":"Sumitomo Heavy Industries, Ltd., Yokosuka 237-0061, Japan"}]},{"given":"Shoji","family":"Tsunematsu","sequence":"additional","affiliation":[{"name":"Sumitomo Heavy Industries, Ltd., Yokosuka 237-0061, Japan"}]},{"given":"Takanori","family":"Kato","sequence":"additional","affiliation":[{"name":"Sumitomo Heavy Industries, Ltd., Yokosuka 237-0061, Japan"}]},{"given":"Yuji","family":"Matsubara","sequence":"additional","affiliation":[{"name":"Sumitomo Heavy Industries, Ltd., Yokosuka 237-0061, Japan"}]},{"given":"Hiromu","family":"Sakai","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Waseda University, Tokyo 169-8555, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1038\/nn.4504","article-title":"Magnetoencephalography for brain electrophysiology and imaging","volume":"20","author":"Baillet","year":"2017","journal-title":"Nat. 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