Using radioactive isotopes and non-sealed labeling compounds, the brain’s mechanism of action could be analyzed from a molecular perspective using the characteristics of a positron emission tomography (PET) image, which could identify molecular changes in the region of interest in the human body in three dimensions. Similarly, magnetic resonance imaging (MRI) images provide high-resolution anatomical information to determine the activity of nerve cells that reflect the activity of brain neurotransmitters and receptors. After measuring the brain neurotransmitter through MRI images and the amount of Blood Oxygenation Level Dependent (BOLD) produced by receptors, certain areas of the brain could identify activation changes. The development of positron emission tomography-magnetic resonance imaging (PET-MRI) has been made to reflect the respective characteristics of PET and MRI images at the same time.

The purpose of this study was to find out how to apply repetitive transcranial magnetic stimulation (rTMS) for neurological condition in clinical practice. Repetitive transcranial magnetic stimulation (rTMS) can be largely applied in four rTMS protocol: low frequency rTMS (LF-rTMS), high frequency rTMS (HF-rTMS), theta burst stimulation (TBS), and paired associative stimulation (PAS). Specifically, LF-rTMS and continuous TBS (cTBS) are methods of suppressing the excitability of the cerebral cortex, and HF-rTMS and intermittent TBS (iTBS) are used as methods of increasing the excitability of the cortex. PAS is being introduced as a method in which excitability can be suppressed or increased depending on the price between stimulation for afferent information and stimulation for TMS. In addition, rTMS can be used in combination with residual effects and other protocol depending on the differences in applied methods. Further research will have to be explained by including effects such as differences in the number and intensity of stimulation used in the rTMS clinical application. Through the four clinical applications of rTMS presented in this study, it is expected to be used as a basis for future TMS protocol.

Immunoassay is a protein-based in vitro diagnostic method using the antigen-antibody immune response of an analyte. Immunoassay is widely used in point-of-care testing in the form of an assay kit for detecting diseases and biochemicals inexpensively and quickly in addition to hospitals and laboratories. Recently, immunoassay devices using a fluorescence analyzer have been developed and distributed to increase detection sensitivity and enable signal quantification. Besides, a technology to further increase the sensitivity by concentrating a low-concentration analyte using magnetic nanoparticles is being developed. In this paper, the patent trend of the magnetic-fluorescent composite technology is investigated and analyzed. Three hundred thirty-four patents filed in Korea, the United States, Europe, Japan, and China were analyzed for fluorescent particles, magnetic particles, and lateral flow strip sensors used in immunoassay. The number of applications is large in the order of China, Japan, the United States, Korea, and Europe, and has been increasing rapidly in the 2010s. Technologies relating to fluorescent particles used for immunoassay are actively progressing, and applications for magnetic-fluorescent composites are increasing in recent years. China is actively developing magnetic-fluorescent composites and strip sensor applications. In Korea, the United States, Europe, and Japan, applications were evenly filed for all fields of particles for immunoassay. For strip sensors, patent applications for the device and analysis method can be found.

Non-invasive imaging techniques such as Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) provide morphological and functional images having important diagnostic information. The combination of the two devices can provide optimal biological and anatomical imaging technology, but when the two systems are combined, electromagnetic interference occurs, which causes the degradation of the resultant image. In this paper, the eddy current that distorts the MR image by inducing heterogeneity in the internal main magnetic field (B₀ field) of the MRI by acquiring and analyzing the image of the metallic shield installed inside the MRI and constituting the integrated Silicon Photomultiplier (SiPM) detector module. An evaluation method for the effect of eddy current was proposed by quantifying the magnetic field interference which induced from the shielding body of the PET detector in the hybrid MRI system.

We investigate the magnetic proprieties of [Co/Ni]-NiFe exchange spring magnets having 1) different thick NiFe layers, 2) two different stack sequences, and 3) different thick Cu spacer between [Co/Ni] multilayers and NiFe layer. We show that the magnetization tilt angle can be tuned from out-of-plane (OOP) to in-plane (IP) by varying the NiFe thickness (t_NiFe) larger than t_NiFe = 1.5 nm, while similar transition occurs from thinner t_NiFe when NiFe layer was deposited earlier than [Co/Ni] multilayers. Finally, we insert Cu spacer between [Co/Ni] multilayers and NiFe layer to figure out how strongly these are coupled. We find the rapid decoupling behavior as a increase of Cu spacer thickness (t_Cu) between 0.5 and 1.3 nm.

We propose a guideline on development of grain boundary diffusion process for high-performance Nd-Fe-B sintered magnets based on recent analytical works revealing the microstructural characteristics of HRE (Heavy Rare-earth)-rich shells and Nd-rich phases in grain boundary diffusion processed magnets. A different diffusion behavior of HRE within the magnets depending on the type of diffusing materials was characterized, and the systematic changes in structure and chemistry of the Nd-rich grain boundary phases during the grain boundary diffusion process were analyzed. Through a detailed microstructure observation using the SEM and HAADF-STEM combined with the EDS and WDS, the formation mechanism of HRE-rich shell could be established from two perspectives: i) solid diffusion of HRE atoms and ii) chemically induced liquid film migration (CILFM). Thereby, the origin of the asymmetric feature of HRE-rich shells along the grain boundary phases was also clarified. Based on the results from microstructure characterization, a microstructure control technique for further improving the coercivity of Nd-Fe-B sintered magnets by the grain boundary diffusion process will be proposed.