An Enhanced Optical Coherence Microscope for the Study of Dynamic Processes in the Early Development of Plants and Animals

Harvey Mudd学院的Richard Haskell博士获得了一笔拨款，用于建造光学相干显微镜（OCM），以捕捉植物和动物早期发育动态过程的三维图像。Harvey Mudd的一个由科学家和工程师组成的跨学科团队将记录发生在发育生物体表面以下300至500毫米处的关键事件，由于胚胎组织的强光散射特性，这一深度对其他基于光的方法来说太深了。OCM仪器能够对单个植物或动物的发育进行无创成像，这将为充分了解基因表达与组织发育过程中发生的结构变化之间的关系提供关键工具。OCM仪器的光源将是运行在近红外（1300 nm）的超快激光，以在生物组织中提供良好的深度穿透。激光输出将有一个广泛的光谱，结果在5毫米的显微镜的深度分辨率。横向分辨率由聚焦光斑直径提供，也是5毫米。为OCM开发的激光系统将由一家商业供应商销售，以便其他研究人员可以使用。此外，该仪器将能够测量散射运动，例如布朗运动，这在初步实验中已被证明可以在不同细胞类型之间提供有效的内在对比。局部折射率变化的测量也将作为本征对比度的来源。新的OCM仪器将用于研究青蛙胚胎的发育和植物芽尖组织的分化。OCM图像将被组装成动态过程的延时图像，允许对提出的细胞运动和分化模型进行第一次直接测试。研究团队将主要由Harvey Mudd学院的四名教员和四所研究型大学的合作者组成。他们的背景涵盖了物理学、生物学和工程学。来自Harvey Mudd所有6个主要项目的约30名本科生研究人员将在夏季和学年期间为该项目做出重大贡献。该项目的多学科性质为整合研究和教育提供了一个不同寻常的机会，从而为学生和教师提供了特殊的培训。参与者被激励在科学和工程领域发展事业，并追求跨越传统学科线的重大研究问题。

A grant has been awarded to Dr. Richard Haskell at Harvey Mudd College to construct an optical coherence microscope (OCM) to capture three-dimensional images of dynamic processes in the early development of plants and animals. An interdisciplinary team of scientists and engineers at Harvey Mudd will record critical events that occur 300 to 500 mm below the surface of a developing organism, too deep to be accessible to other light-based methods because of the strong light-scattering property of embryonic tissue. The ability of the OCM instrument to image non-invasively the development of an individual plant or animal will provide a key tool for gaining a full understanding of the relationship between gene expression and the structural changes that occur during tissue development.The light source of the OCM instrument will be an ultrafast laser operating in the near infrared (1300 nm) to provide good depth penetration in biological tissue. The laser output will have a broad spectrum that results in a depth resolution for the microscope of 5 mm. The lateral resolution is provided by the focused spot diameter, also 5 mm. The laser system developed for the OCM will be marketed by a commercial vendor so that it is available to other researchers. In addition, the instrument will be capable of measuring scatter motion, for example Brownian motion, which in preliminary experiments has been shown to provide effective intrinsic contrast between different cell types. Measurements of the local variation in refractive index will also serve as a source of intrinsic contrast. The new OCM instrument will be used to study the development of frog embryos and the differentiation of tissue at the apex of plant shoots. OCM images will be assembled to form time-lapse images of dynamic processes, permitting the first direct tests of proposed models of cell motions and differentiation. The research team will consist primarily of four faculty at Harvey Mudd College plus collaborators at four research universities. Their backgrounds span the disciplines of physics, biology, and engineering. An estimated 30 undergraduate researchers, drawn from all 6 major programs at Harvey Mudd, will make significant contributions to the program both during the summer and the academic year. The multidisciplinary nature of the project provides an unusual opportunity to integrate research and education resulting in exceptional training for students and faculty alike. Participants are motivated to develop careers in science and engineering, and to pursue significant research problems that stretch across traditional disciplinary lines.