The evident advantage of high-field MR (magnetic resonance) scanners is their higher signal-to-noise ratio, which results in improved imaging. While no reliable efficacy studies exist that compare the diagnostic capabilities of low- versus high-field scanners, the adoption and acceptance of low-field MRI (magnetic resonance imaging) is subject to biases. On the other hand, the cost savings associated with low-field MRI hardware are obvious. The running costs of a non-superconductive low-field scanner show even greater differences in favor of low-field scanners. Patient anxiety and safety issues also reflect the advantages of low-field scanners. Recent technological developments in the realm of low-field MR scanners will lead to higher image quality, shorter scan times, and refined imaging protocols. Interventional and intraoperative use also supports the installation of low-field MR scanners. Utilization of low-field systems has the potential to enhance overall cost reductions with little or no loss of diagnostic performance.

The morning overshoot in electron temperature, Te, which occurs in the sunlit atmosphere of low electron density during early morning hours, is a well known phenomenon. Studies of the phenomenon carried out using the Hinotori satellite observations reveal that the overshoot enhances in the topside equatorial F-region for a short period of time in the morning. The enhancement in the overshoot is found to depend on season and solar activity; it is strong during the northern summer months and grows with the increase in solar activity. Theoretical model calculations show that the enhancement in Te is caused by a reduction in electron density in the topside ionosphere due to a downward drift of plasma.

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By the impedance probe (IMP) on board the Hinotori satellite, that was profiles of electron density contain the data of the equatorial plasma bubbles. Preliminary statistic studies on the occurrence frequency indicate that there are at least three types of the plasma bubbles. The plasma bubbles that belong to the first type grow mainly from the evening to the midnight period with large depletion rates of electron density; since the depletion regions are sequencially aligned those are called here multiple plasma bubbles (MPB). The second type plasma bubbles are enhanced mainly after midnight, even in sunlit condition, with periodic features and are called here quasi periodic plasma bubbles (QPB). There is a third type of plasma bubble characterized by its solitary features called here solitary plasma bubble (SPB). The SPB phenomena takes place in all of the night time period. In the topside region of the ionosphere near the edge of the occurrence region of the plasma bubble, there frequently appear electron density enhancements with deviation of a few percent to the background electron density. These newly discovered phenomena are called here plasma blob. Occurrence characteristics of the plasma blob are also discussed.