Magnetic resonance imaging (MRI) has been widely used as gold standard of many clinical diagnostics. However, traditional MRI systems have high demands on facility settings and are often costly. Recently, portable low-field MRI systems have shown promising compatibility to different conditions. In this work, we obtained image on two portable low-field MRI systems, using an open-source MRI control system called MaRCoS.

Steady-state visual evoked fields (SSVEF) signals have a wide range of applications in brain-computer interface (BCI). An SSVEF system commonly uses multi-channel sensors to measure the signals simultaneously, which reduces the portability and increases the cost of the system. This paper studies the distribution of the human brain visually evoked magnetic field experimentally and then presents an SSVEF system based on a single optically pumped magnetometer (OPM). The sensor is placed at the position with maximum magnetic signal amplitude. A BCI system employing a magnetic field compensation system to suppress the low-frequency magnetic field fluctuation and the power line interference is developed and tested, where the subject under test can control the movement of an object in a game to avoid objects based on the SSVEF measurement. This system can potentially be used to develop BCI games and medical aid instruments.

In this report, an antenna for wireless power feeding systems using sewing technology was described. The reflection loss of the antenna was -8 dB in a simulation and -11 dB The difference between the values in the simulation and measurement can be resulted from the dielectric material to support the antenna.

Litz wire has flexibility and low loss due to skin effect. Flexible coils can be fabricated by sewing or stitching the wire into cloth. Magnetic field resonant power transmission with those coils has been researched. In the magnetic resonant power transmission, it is important to increase the Q value of the coil. To increase the Q value of the coil, it is necessary to reduce the coil loss. Coil losses include DC loss, proximity effect, skin effect, and loss due to stray capacitance. In this study, we evaluated the losses in sewn coils in the frequency range from 1 to 15 MHz in terms of proximity effect and stray capacitance. As a result, the loss due to stray capacitance is significant for the loss between coils.

This paper describes the transmission efficiencies of fractal antennas using sewing technology for efficient wireless power transmission to implantable devices such as artificial hearts. Since the use of percutaneous power sources can cause infections, contactless power transmission is considered a safer option. The Vicsec fractal pattern antennas fabricated with a sewing technique were proposed. The size of the antennal can be reduced by using the pattern. The transmission efficiencies of a fabricated antenna were around -30 to -40 dB at a designed frequency.

In recent years, wireless power transmission has attracted attention as a method of supplying power to medical devices in the body. This study proposes magnetic field resonance wireless power transmission using an auxiliary coil sewn into clothing and a coil to match the impedance of the circuit. The system is designed to supply power to implantable medical devices while the patient is lying in bed, with the auxiliary coil sewn into the garment and the matching coil placed on the power transmission coil side. The auxiliary coil is used as a repeater to improve the coupling coefficient between the transmitter and receiver. The matching coil is installed to prevent reflection of electricity due to impedance mismatch. The conditions for efficient power transmission were investigated using a simulation software.

We develop a PCR method utilizing carbon-coated iron (Fe@C) nanoparticles. The outer carbon layers of the particles absorb near-infrared (NIR) light and release energy as heat. We carry out PCR performing thermal cycling via the on/off operation of NIR irradiation to the particles. We show that the total time of PCR is shortened compared to the conventional method thanks to rapid, efficient heating by Fe@C nanoparticles. We also show that the total amount of by-products is smaller than the conventional case, which may be attributed to the rapid thermal cycling.

Recently, wireless power transmission has been attracting attention as a method of supplying power to medical devices inside the body. Wireless power transmission using electromagnetic waves has been studied for long-distance transmission. In this report, a three-antenna system with a sewn auxiliary antenna is proposed. The auxiliary antenna sewn into clothing such as a shirt is worked as a repeater between power transmitting antennas and a receiving antenna inside the body. As a first step, the transmission characteristics between the auxiliary antenna and the power receiving antenna were evaluated.