Localization of active neural source (ANS) from measurements on head surface is vital in magnetoencephalography. As neuron-generated magnetic fields are extremely weak, significant uncertainties caused by stochastic measurement interference complicate its localization. This paper presents a novel computational method based on reconstructed magnetic field from sparse noisy measurements for enhanced ANS localization by suppressing effects of unrelated noise. In this approach, the magnetic flux density (MFD) in the nearby current-free space outside the head is reconstructed from measurements through formulating the infinite series solution of the Laplace's equation, where boundary condition (BC) integrals over the entire measurements provide "smooth" reconstructed MFD with the decrease in unrelated noise. Using a gradient-based method, reconstructed MFDs with good fidelity are selected for enhanced ANS localization. The reconstruction model, spatial interpolation of BC, parametric equivalent current dipole-based inverse estimation algorithm using reconstruction, and gradient-based selection are detailed and validated. The influences of various source depths and measurement signal-to-noise ratio levels on the estimated ANS location are analyzed numerically and compared with a traditional method (where measurements are directly used), and it was demonstrated that gradient-selected high-fidelity reconstructed data can effectively improve the accuracy of ANS localization.
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http://dx.doi.org/10.1007/s11517-015-1381-9 | DOI Listing |
Front Med (Lausanne)
December 2024
Division of Cardiovascular Sciences, School of Medical Sciences, University of Manchester, Manchester, United Kingdom.
Background: The sinoatrial node (SN) generates the heart rate (HR). Its spontaneous activity is regulated by a complex interplay between the modulation by the autonomic nervous system (ANS) and intrinsic factors including ion channels in SN cells. However, the systemic and intrinsic regulatory mechanisms are still poorly understood.
View Article and Find Full Text PDFActa Neurochir (Wien)
December 2024
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke Hospital, University of Cambridge, Cambridge, UK.
Background: Traumatic brain injury (TBI) can significantly disrupt autonomic nervous system (ANS) regulation, increasing the risk for secondary complications, hemodynamic instability, and adverse outcome. This retrospective study evaluated windowed time-lagged cross-correlation (WTLCC) matrices for describing cerebral hemodynamics-ANS interactions to predict outcome, enabling identifying high-risk patients who may benefit from enhanced monitoring to prevent complications.
Methods: The first experiment aimed to predict short-term outcome using WTLCC-based convolution neural network models on the Wroclaw University Hospital (WUH) database (P = 31 with 1,079 matrices, P = 16 with 573 matrices).
Chin J Dent Res
December 2024
Objective: To establish precise positional references for orthognathic surgery by examining the relative positioning of the infraorbital foramen (IOF) in relation to the anterior nasal spine (ANS) and the mental foramen (MF) in relation to the pogonion (Pog).
Methods: A cohort of 115 patients with CBCT images was randomly selected for analysis. Distances and positional relationships between the IOF and ANS, as well as the MF and Pog, were measured using 3D reconstruction images.
BMC Plant Biol
December 2024
College of Forestry and Prataculture, Ningxia University, Yinchuan, 750021, China.
Food Res Int
November 2024
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, College of Horticulture & Landscape Architecture, Northeast Agricultural University, Harbin 150030, China; National-Local Joint Engineering Research Center for Development and Utilization of Small Fruits in Cold Regions, Northeast Agricultural University, Harbin 150030, China. Electronic address:
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