Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.1-9
핵 의학 영상 획득에 대한 이해와 발전
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.
Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.10-15
반복 경두개 자기 자극의 프로토콜 및 임상 적용
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.
Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.16-25
면역진단용 자성-형광 복합체 기술의 특허 동향
Immunoassay is a protein-based
Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.26-33
자기공명영상장치에서 양전자방출단층촬영 모듈의 와전류 영향 평가
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 (
Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.34-38
[Co/Ni]-NiFe 교환스프링 자석의 자성 특성에 관한 연구
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 (
Journal of the Korean Magneitcs Society, 23 Feb 2021, Vol.31 , No.1, pp.39-52
고성능 Nd-Fe-B 소결자석 제조를 위한 입계 확산 공정의 개발 방향
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.