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Magnetoencephalography (MEG) records the brain magnetic field signals. Optically pumped magnetometer (OPM) is a novel technology for MEG measurement in its infancy, it is essential to demonstrate its performance on the key neuroimaging features, such as phase-locking value. In this paper, the inter-trial phase-locking value (ITPL) and inter-region phase-locking value (IRPL) were analyzed by simulation and measurement experiments using OPM-MEG, the superconducting quantum interference device (SQUID) data was applied for the compare. The simulation results show that OPMs could offers good characterization on phase-locking value under higher noise intensity. In experiments, the similarity ratios of ITPL and IRPL between OPM-MEG and SQUID-MEG are >0.90. The significantly increased frequencies of IRPL in pure tone and somatosensory stimulation are at about 10–20 Hz and 8–13 Hz respectively, with Spearman correlation coefficients >0.7. The results provide experimental evidence of the ability of OPM-MEG for measuring phase synchronization and functional connectivity on sensor signals. [Display omitted] • OPM offers good characterization on phase-locking value under higher noise level. • With SNR increased within 0–15 dB, phase-locking value increases linearly. • This is the first study to measure IRPL on sensor signals using OPM. • The correlation of IRPL is >0.7 between OPM and SQUID. [ABSTRACT FROM AUTHOR]

Climate changes, including sea level rise (SLR) and typhoon intensification (TI), have been widely accepted in coastal communities and significantly affect coastal engineering. In this work, an integrally-coupled tide-surge-wave model was developed to simulate storm tides and waves around the coastal area of Qingdao. The model was validated with observed data under historical typhoon events. The simulated results illustrate that tides change obviously at most representative stations within Jiaozhou Bay. Meanwhile, the effect of SLR on astronomical tide in the flood and the ebb period is more significant than that of the peak tide period. Further investigations reveal that SLR and TI affect storm tides and waves in different ways and the influences are different within Jiaozhou Bay and along the open coast. Besides, the combined effects of SLR and TI on peak storm tides and wave heights are remarkable, which are not a simply linear superposition and present a spatially non-uniform and non-liner pattern. Therefore, it is essential to adopt the coupled model to estimate the possible maximum risk of storm surges and waves around the coastal area of Qingdao. Taking SLR and TI into consideration, the peak of elevation near shore could experience a significant amplification in the future. • An integrally-coupled tide-surge-wave model is developed. • Storm surge and wave modeling in the coastal area of Qingdao is carried out. • The differences of storm surge between coupled and uncoupled models are analyzed. • The effects of climate changes on tides, storm surges and waves are investigated in the study area. • The possible maximum risk of storm surges and waves in 2100 is estimated around the coastal area of Qingdao. [ABSTRACT FROM AUTHOR]