2018 Conference on Precision Electromagnetic Measurements (CPEM 2018), 2018
A novel technique to extract the quotient of gyromagnetic ratios in a comagnetometer system is pr... more A novel technique to extract the quotient of gyromagnetic ratios in a comagnetometer system is presented. This technique aims to probe the quotient in a regime which is free from the spin-relaxation related systematic effects. It is based on the measurement of spin precession frequencies in a gaseous mixture of 129Xe and3He at ultralow magnetic field. The resultant quotient value appears to be close to the literature value.
Otto J, Migas K, Järvinen H, Burghoff M. Interkulturelle Kompetenz von Lehrkräften. Mythos, Trend... more Otto J, Migas K, Järvinen H, Burghoff M. Interkulturelle Kompetenz von Lehrkräften. Mythos, Trend oder pädagogische Notwendigkeit? In: McElvany N, Bos W, Holtappels HG, Jungermann A, eds. Ankommen in der Schule. Chancen und Herausforderungen bei der Integration von Kindern und Jugendlichen mit Fluchterfahrung. Münster: Waxmann; 2017: 69-85
High resolution magnetocardiography (HR MCG) is a new and promising method of studying heart acti... more High resolution magnetocardiography (HR MCG) is a new and promising method of studying heart activity. One of the most interesting clinical applications of HR MCG is the localization of pathological cardiac sources which has often been demonstrated (Erne, 1985, Fenici et al., 1985, Katila et al., 1987). For the localization appropriate source and thorax models are needed.
Magnetic fields over the lower back generated by electric action currents in stimulated leg nerve... more Magnetic fields over the lower back generated by electric action currents in stimulated leg nerves were recorded inside a magnetically shielded room with a multichannel dc-SQUID system. Spatio-temporal field maps show the propagation of these action currents along the nerves. The proposed analysis of the nerve magnetic fields is based on the multipole expansion and takes into account that activated nerve segments are linearly extended field sources. This source analysis allows the estimation of characteristic source parameters, such as depth below the body surface, spatial extent, and current strength.
The knowledge of the temporal relation between neuronal activity and the accompanying changes in ... more The knowledge of the temporal relation between neuronal activity and the accompanying changes in the vascular system of the brain may foster a better understanding of fMRI. We have devised a triple-modality measurement setup comprising broadband DC-magnetoencephalography (DC-MEG), time-resolved near-infrared spectroscopy (trNIRS) and peripheral physiological signal monitoring. The neuronal activity was measured using a broadband DC-MEG with a temporal resolution on the scale of tens of ms. In order to obtain trNIRS signals reflecting cortical vascular processes the variance was derived for the distributions of time-of-flight of photons. Confounding physiological signals such as heart beat, respiration, and electromyographical activity (EMG) were recorded simultaneously. The subjects had to repeat a sequence of 30 s of finger movement followed by 30s of rest motivating the EMG. Independent component analysis (ICA) was applied separately to the DC-MEG and the trNIRS data for preproces...
The detection of neuronal currents (NC) may foster the understanding of the flow of information i... more The detection of neuronal currents (NC) may foster the understanding of the flow of information in the brain. Existing methods of NC detection like electro- and magnetoencephalography (EEG/MEG) are limited by the ambiguity of the inverse problem, while imaging methods like fMRI monitor secondary effects (e.g., blood oxygenation changes). On the other hand, attempts to directly detect NC in high field NMR techniques by a local shift of the 1H resonance frequency have yielded controversial results. In magnetic fields around 1 microTesla, the relative contribution of the biomagnetic field generated by neuronal currents is orders of magnitude higher than in conventional high fields. This may make the situation much more favourable.
2018 Conference on Precision Electromagnetic Measurements (CPEM 2018), 2018
A novel technique to extract the quotient of gyromagnetic ratios in a comagnetometer system is pr... more A novel technique to extract the quotient of gyromagnetic ratios in a comagnetometer system is presented. This technique aims to probe the quotient in a regime which is free from the spin-relaxation related systematic effects. It is based on the measurement of spin precession frequencies in a gaseous mixture of 129Xe and3He at ultralow magnetic field. The resultant quotient value appears to be close to the literature value.
Otto J, Migas K, Järvinen H, Burghoff M. Interkulturelle Kompetenz von Lehrkräften. Mythos, Trend... more Otto J, Migas K, Järvinen H, Burghoff M. Interkulturelle Kompetenz von Lehrkräften. Mythos, Trend oder pädagogische Notwendigkeit? In: McElvany N, Bos W, Holtappels HG, Jungermann A, eds. Ankommen in der Schule. Chancen und Herausforderungen bei der Integration von Kindern und Jugendlichen mit Fluchterfahrung. Münster: Waxmann; 2017: 69-85
High resolution magnetocardiography (HR MCG) is a new and promising method of studying heart acti... more High resolution magnetocardiography (HR MCG) is a new and promising method of studying heart activity. One of the most interesting clinical applications of HR MCG is the localization of pathological cardiac sources which has often been demonstrated (Erne, 1985, Fenici et al., 1985, Katila et al., 1987). For the localization appropriate source and thorax models are needed.
Magnetic fields over the lower back generated by electric action currents in stimulated leg nerve... more Magnetic fields over the lower back generated by electric action currents in stimulated leg nerves were recorded inside a magnetically shielded room with a multichannel dc-SQUID system. Spatio-temporal field maps show the propagation of these action currents along the nerves. The proposed analysis of the nerve magnetic fields is based on the multipole expansion and takes into account that activated nerve segments are linearly extended field sources. This source analysis allows the estimation of characteristic source parameters, such as depth below the body surface, spatial extent, and current strength.
The knowledge of the temporal relation between neuronal activity and the accompanying changes in ... more The knowledge of the temporal relation between neuronal activity and the accompanying changes in the vascular system of the brain may foster a better understanding of fMRI. We have devised a triple-modality measurement setup comprising broadband DC-magnetoencephalography (DC-MEG), time-resolved near-infrared spectroscopy (trNIRS) and peripheral physiological signal monitoring. The neuronal activity was measured using a broadband DC-MEG with a temporal resolution on the scale of tens of ms. In order to obtain trNIRS signals reflecting cortical vascular processes the variance was derived for the distributions of time-of-flight of photons. Confounding physiological signals such as heart beat, respiration, and electromyographical activity (EMG) were recorded simultaneously. The subjects had to repeat a sequence of 30 s of finger movement followed by 30s of rest motivating the EMG. Independent component analysis (ICA) was applied separately to the DC-MEG and the trNIRS data for preproces...
The detection of neuronal currents (NC) may foster the understanding of the flow of information i... more The detection of neuronal currents (NC) may foster the understanding of the flow of information in the brain. Existing methods of NC detection like electro- and magnetoencephalography (EEG/MEG) are limited by the ambiguity of the inverse problem, while imaging methods like fMRI monitor secondary effects (e.g., blood oxygenation changes). On the other hand, attempts to directly detect NC in high field NMR techniques by a local shift of the 1H resonance frequency have yielded controversial results. In magnetic fields around 1 microTesla, the relative contribution of the biomagnetic field generated by neuronal currents is orders of magnitude higher than in conventional high fields. This may make the situation much more favourable.
Uploads
Papers by Martin Burghoff