Search Results - "Dabek, Juhani"

Hybrid ultra-low-field MRI and magnetoencephalography system based on a commercial whole-head neuromagnetometer by Vesanen, Panu T., Nieminen, Jaakko O., Zevenhoven, Koos C. J., Dabek, Juhani, Parkkonen, Lauri T., Zhdanov, Andrey V., Luomahaara, Juho, Hassel, Juha, Penttilä, Jari, Simola, Juha, Ahonen, Antti I., Mäkelä, Jyrki P., Ilmoniemi, Risto J.

“…Ultra‐low‐field MRI uses microtesla fields for signal encoding and sensitive superconducting quantum interference devices for signal detection. Similarly,…”
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Marked difference in liver fat measured by histology vs. magnetic resonance-proton density fat fraction: A meta-analysis by Qadri, Sami, Vartiainen, Emilia, Lahelma, Mari, Porthan, Kimmo, Tang, An, Idilman, Ilkay S., Runge, Jurgen H., Juuti, Anne, Penttilä, Anne K., Dabek, Juhani, Lehtimäki, Tiina E., Seppänen, Wenla, Arola, Johanna, Arkkila, Perttu, Stoker, Jaap, Karcaaltincaba, Musturay, Pavlides, Michael, Loomba, Rohit, Sirlin, Claude B., Tukiainen, Taru, Yki-Järvinen, Hannele

“…Pathologists quantify liver steatosis as the fraction of lipid droplet-containing hepatocytes out of all hepatocytes, whereas the magnetic resonance-determined…”
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Suppressing multi-channel ultra-low-field MRI measurement noise using data consistency and image sparsity by Lin, Fa-Hsuan, Vesanen, Panu T, Hsu, Yi-Cheng, Nieminen, Jaakko O, Zevenhoven, Koos C J, Dabek, Juhani, Parkkonen, Lauri T, Simola, Juha, Ahonen, Antti I, Ilmoniemi, Risto J

“…Ultra-low-field (ULF) MRI (B 0 = 10-100 µT) typically suffers from a low signal-to-noise ratio (SNR). While SNR can be improved by pre-polarization and signal…”
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Marked underestimation of liver fat content as measured by magnetic resonance versus histology—a systematic review and meta-analysis by Qadri, Sami, Porthan, Kimmo, Juuti, Anne, Penttilä, Anne, Dabek, Juhani, Lehtimäki, Tiina E., Seppänen, Wenla, Arola, Johanna, Arkkila, Perttu, Yki-Järvinen, Hannele

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The PNPLA3 I148M variant increases intrahepatic lipolysis and beta oxidation and decreases de novo lipogenesis and hepatic mitochondrial function in humans by Luukkonen, Panu, Porthan, Kimmo, Ahlholm, Noora, Rosqvist, Fredrik, Dufour, Sylvie, Zhang, Xian-Man, Dabek, Juhani, Lehtimäki, Tiina, Seppänen, Wenla, Orho-Melander, Marju, Hodson, Leanne, Petersen, Kitt Falk, Shulman, Gerald I., Yki-Järvinen, Hannele

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Determination of head conductivity frequency response in vivo with optimized EIT-EEG by Dabek, Juhani, Kalogianni, Konstantina, Rotgans, Edwin, van der Helm, Frans C.T., Kwakkel, Gert, van Wegen, Erwin E.H., Daffertshofer, Andreas, de Munck, Jan C.

“…Electroencephalography (EEG) benefits from accurate head models. Dipole source modelling errors can be reduced from over 1cm to a few millimetres by replacing…”
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Detecting millisecond-range coupling delays between brainwaves in terms of power correlations by magnetoencephalography by Dabek, Juhani, Nikulin, Vadim V., Ilmoniemi, Risto J.

“…[Display omitted] •A new method to detect power correlations (PCs) between brainwaves is presented.•The millisecond resolution of the PC method is demonstrated…”
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Temperature dependence of relaxation times and temperature mapping in ultra-low-field MRI by Vesanen, Panu T., Zevenhoven, Koos C.J., Nieminen, Jaakko O., Dabek, Juhani, Parkkonen, Lauri T., Ilmoniemi, Risto J.

“…•Relaxation times of agarose gel are measured at fields of 50μT–3T and at temperatures of 5–45°C.•Interestingly, the effect of temperature on agarose gel T1…”
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Avoiding eddy-current problems in ultra-low-field MRI with self-shielded polarizing coils by Nieminen, Jaakko O., Vesanen, Panu T., Zevenhoven, Koos C.J., Dabek, Juhani, Hassel, Juha, Luomahaara, Juho, Penttilä, Jari S., Ilmoniemi, Risto J.

“…[Display omitted] ► We present a solution to the eddy-current problem in ultra-low-field MRI. ► Self-shielded polarizing coils produce weak stray fields. ►…”
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Rotary scanning acquisition in ultra-low-field MRI by Hsu, Yi-Cheng, Zevenhoven, Koos C.J., Chu, Ying-Hua, Dabek, Juhani, Ilmoniemi, Risto J., Lin, Fa-Hsuan

“…Purpose To develop a method of achieving large field of view (FOV) imaging with a smaller amount of data in ultra‐low‐field (ULF) MRI. Theory In rotary…”
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Efficient concomitant and remanence field artifact reduction in ultra-low-field MRI using a frequency-space formulation by Hsu, Yi-Cheng, Vesanen, Panu T., Nieminen, Jaakko O., Zevenhoven, Koos C.J., Dabek, Juhani, Parkkonen, Lauri, Chern, I-Liang, Ilmoniemi, Risto J., Lin, Fa-Hsuan

“…Purpose For ultra‐low‐field MRI, the spatial‐encoding magnetic fields generated by gradient coils can have strong concomitant fields leading to prominent image…”
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Optimized in vivo conductivity estimation using BEM by de Munck, Jan C, Dabek, Juhani, Hulshof, Joost

“…One of the most important factors limiting the accuracy of source localization with EEG is the ignorance of the conductivity of brain, skull and skin. Because…”
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Noise amplification in parallel whole-head ultra-low-field magnetic resonance imaging using 306 detectors by Lin, Fa-Hsuan, Vesanen, Panu T., Nieminen, Jaakko O., Hsu, Yi-Cheng, Zevenhoven, Koos C.J., Dabek, Juhani, Parkkonen, Lauri T., Zhdanov, Andrey, Ilmoniemi, Risto J.

“…In ultra‐low‐field magnetic resonance imaging, arrays of up to hundreds of highly sensitive superconducting quantum interference devices (SQUIDs) can be used…”
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SQUID-sensor-based ultra-low-field MRI calibration with phantom images: Towards quantitative imaging by Dabek, Juhani, Vesanen, Panu T., Zevenhoven, Koos C.J., Nieminen, Jaakko O., Sepponen, Raimo, Ilmoniemi, Risto J.

“…[Display omitted] ► An ultra-low-field (ULF) MR image of a phantom is measured. ► Corresponding images are generated by simulation. ► Sensor and…”
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The Spatial and Temporal Distortion of Magnetic Fields Applied Inside a Magnetically Shielded Room by Vesanen, Panu T., Nieminen, Jaakko O., Zevenhoven, Koos C. J., Dabek, Juhani, Simola, Juha, Sarvas, Jukka, Ilmoniemi, Risto J.

“…In the context of biomagnetism, a magnetically shielded room (MSR) is designed for shielding against external magnetic fields. Recently, several applications,…”
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Hybrid ultra-low-field MRI and magnetoencephalography system based on a commercial whole-head neuromagnetometer by Vesanen, Panu T., Nieminen, Jaakko O., Zevenhoven, Koos C. J., Dabek, Juhani, Parkkonen, Lauri T., Zhdanov, Andrey V., Luomahaara, Juho, Hassel, Juha, Penttilä, Jari, Simola, Juha, Ahonen, Antti I., Mäkelä, Jyrki P., Ilmoniemi, Risto J.

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Improved determination of FID signal parameters in low-field NMR by Dabek, Juhani, Nieminen, Jaakko O., Vesanen, Panu T., Sepponen, Raimo, Ilmoniemi, Risto J.

“…In this work, novel methods are suggested for assessing signal parameters of the free induction decay (FID) in nuclear magnetic resonance (NMR) experiments…”
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Relationship of electrocardiographic repolarization measures to echocardiographic left ventricular mass in men with hypertension by Porthan, Kimmo, Virolainen, Juha, Hiltunen, Timo P, Viitasalo, Matti, Väänänen, Heikki, Dabek, Juhani, Hannila-Handelberg, Tuula, Toivonen, Lauri, Nieminen, Markku S, Kontula, Kimmo, Oikarinen, Lasse

“…OBJECTIVEArterial hypertension often leads to an increase in left ventricular mass (LVM). Marked left ventricular hypertrophy (LVH) is associated with…”
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Short-term electrophysiological effects of losartan, bisoprolol, amlodipine, and hydrochlorothiazide in hypertensive men by Porthan, Kimmo, Viitasalo, Matti, Hiltunen, Timo P, Vaananen, Heikki, Dabek, Juhani, Suonsyrja, Timo, Hannila-Handelberg, Tuula, Virolainen, Juha, Nieminen, Markku S, Toivonen, Lauri, Kontula, Kimmo, Oikarinen, Lasse

“…Hypertension-induced left ventricular structural remodelling associates with repolarization abnormalities. We investigated if antihypertensive drugs can…”
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Relation of twelve-lead electrocardiographic T-wave morphology descriptors to left ventricular mass by Oikarinen, Lasse, Väänänen, Heikki, Dabek, Juhani, Kaartinen, Maija, Hänninen, Helena, Katila, Toivo, Nieminen, Markku S, Toivonen, Lauri, Viitasalo, Matti

“…Recently, novel T-wave morphology descriptors on the 12-lead ECG were shown to carry important prognostic information on arrhythmic susceptibility in patients…”
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