Development of an EPR imager for the cerebral function analysis

用于脑功能分析的 EPR 成像仪的开发

• 批准号: 14205061
• 负责人: ONO Mitsuhiro
• 金额: $ 35.28万
• 依托单位: Yamagata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14205061/
• 关键词: cerebral function; dog head; EPR; EPRI; ESR; resonator; ATC; AMC

The goal of this study was the development of an EPR imager for the cerebral function analysis. A key problem of the image reconstruction in EPR imaging was tacked. A systematic selection of filtering function to obtain the optimum image resolution was investigated. The direct Fourier transformation reconstitution(DFTR)method is suitable to understand the effect of the filter characteristics. We paid attention to the signal-to-noise ratio of the spectra to determine the cut-off frequency in the filter function. Although the usefulness of the image reconstruction by this technique should be verified in the imaging of more realistic samples, our fundamental concept was confiemed. The frequency characteristics of the noise can be treated as the white noise. Moreover, the technology using the optical device that enables remote control of the resonant frequency was developed for of the volume coil such as a loop-gap resonator. This realized the tuning circuit with less electromagnetic induction by magnetic field modulation which becomes a problem in the use of a varactor diode. The sensitivity was decreased by using the automatic tuning control, but the stability of the measurements was improved. It is necessary to improve the sensitivity in the future. Although it was a research for a very large goal, namely, the development of the EPR imager for the cerebral function analysis, we solved some technical problems. The systematic approach to selecting the cut-off frequency in image reconstruction and the optical technique to control the resonance frequency are useful for EPR study.

本研究的目标是开发用于脑功能分析的 EPR 成像仪。解决了EPR成像中图像重建的关键问题。研究了过滤函数的系统选择以获得最佳图像分辨率。直接傅里叶变换重构（DFTR）方法适合了解滤波器特性的影响。我们关注频谱的信噪比来确定滤波器函数中的截止频率。尽管该技术的图像重建的有用性应该在更真实的样本的成像中得到验证，但我们的基本概念被证实了。噪声的频率特性可以视为白噪声。此外，还针对环隙谐振器等体积线圈开发了使用能够远程控制谐振频率的光学器件的技术。这通过磁场调制实现了具有较小电磁感应的调谐电路，这成为使用变容二极管的问题。使用自动调谐控制会降低灵敏度，但会提高测量的稳定性。以后有必要提高灵敏度。虽然这是一个非常大的目标的研究，即开发用于脑功能分析的EPR成像仪，但我们解决了一些技术问题。选择图像重建截止频率的系统方法和控制共振频率的光学技术对于 EPR 研究非常有用。

项目成果

M.Ono, K.Yamanaka, Y.Nishimoto, H.Susaki, Y.Shimoyama: "Development of a split-type bridged loop-gap resonator"Instrumentation of EPR Spectroscopy (held at Yonezawa, Japan). 18 (2003)

M.Ono、K.Yamanaka、Y.Nishimoto、H.Susaki、Y.Shimoyama：“分体式桥接环隙谐振器的开发”EPR 光谱仪（在日本米泽举行）。

Y.Mase, K.Haga, M.Ono, H.Susaki, Y.Shimoyama: "Development of a cylindrical TE011 cavity resonator used for dog head EPRI"Instrumentation of EPR Spectroscopy (held at Yonezawa, Japan). 20 (2003)

Y.Mase、K.Haga、M.Ono、H.Susaki、Y.Shimoyama：“用于狗头 EPRI 的圆柱形 TE011 空腔谐振器的开发”EPR 光谱仪（在日本米泽举行）。

Mitsuhiro Ono, Tomonori Mase, Koji Haga, Hitoshi Susaki, Yuhei Shimoyama: "Development of a Cylindrical TE_<011> Cavity Resonator used for Dog Head EPRI"The 42th Annual meeting of the society of Electron Spin Science and technology. 1B01 (2003)

Mitsuhiro Ono、Tomonori Mase、Koji Haga、Hitoshi Susaki、Yuhei Shimoyama：“用于狗头 EPRI 的圆柱形 TE_<011> 腔谐振器的开发”电子自旋科学技术学会第 42 届年会。

W.Bodaiji, H.Hirata, M.Ono: "Optically tunable bridged loop-gap resonator"Instrumentation of EPR Spectroscopy (held at Yonezawa, Japan). 15 (2003)

W.Bodaiji、H.Hirata、M.Ono：“光学可调谐桥接环隙谐振器”EPR 光谱仪（在日本米泽举行）。