Frontiers in Nuclear Magnetic Resonance and Magnetic Particle Imaging

该提案要求支持将探索与在极低磁场中进行的核磁共振（NMR）实验相关的基本问题以及与称为磁粒子成像（MPI）的新成像模式相关的机会的研究。NMR是一种非常成熟的实验技术，它使用磁场来探测原子核。它在科学、工程和医学中有许多应用，并构成了磁共振成像（MRI）的基础。MPI在某些方面类似于MRI。它还利用磁场;但不是探测原子核，而是能够检测并快速绘制出非常小的生物相容性磁性颗粒的分布。这些颗粒非常小，可以作为示踪剂注入血液，为研究人员希望成为心血管成像的强大方法打开了大门。 提出了三个不同但互补的调查路线。研究人员将使用甚低场（VLF）NMR来研究原子之间的复杂磁相互作用，首先用激光将它们极化，使它们的原子核最终在同一方向上对齐。这将导致混乱的行为，并将模仿可能限制未来一代NMR光谱仪分辨率的理解不足的过程。研究人员还将利用他们在VLF NMR和MRI设备设计方面的专业知识，帮助推进MPI的新兴和密切相关的领域。为此，他们已经构建了一个原型MPI系统，可以对小物体进行成像;他们现在将专注于从提高灵敏度和图像质量到理解和规避可能限制人类规模成像系统构建的因素等问题。最后，该提案将支持该小组继续和长期努力开发和改进VLF NMR和MRI的工具，技术和应用。

This proposal requests support for research that will explore fundamental questions related to Nuclear Magnetic Resonance (NMR) experiments conducted in very-low magnetic fields and opportunities related to a very new imaging modality, called Magnetic Particle Imaging (MPI). NMR is a very-well established experimental technique that uses magnetic fields to probe the nuclei of atoms. It has many applications in science, engineering, and medicine, and forms the basis for Magnetic Resonance Imaging (MRI). MPI is in some respects similar to MRI. It also makes use of magnetic fields; but instead of probing nuclei, it is able to detect and rapidly map out the distribution of very small biocompatible magnetic particles. These particles are so small that they can be injected into the bloodstream as tracers, opening the door to what researchers hope will become powerful method for cardiovascular imaging. Three distinct but complementary lines of inquiry are proposed. Researchers will use very-low field (VLF) NMR to study complex magnetic interactions between atoms after first polarizing them with lasers, so that their nuclei end up being aligned in the same direction. This will lead to chaotic behaviour and will mimic poorly-understood processes that could limit the resolution of future-generation NMR spectrometers. Researchers will also draw on their expertise in the design of apparatus for VLF NMR and MRI to help advance the emerging and closely-related field of MPI. To this end, they have already constructed a prototype MPI system that can image small objects; they will now focus on issues ranging from the enhancement of sensitivity and image quality to understanding and circumventing factors that might limit the construction of a human-scale imaging system. Finally, the proposal will support continuing and long-term efforts by this group to develop and refine tools, techniques, and applications for VLF NMR and MRI.