IDBR: Development of a System for Measuring Dynamic Biological Responses in Plants using Coincidence Counting

IDBR：开发使用符合计数测量植物动态生物反应的系统

• 批准号: 0649924
• 负责人: Calvin Howell
• 金额: $ 29.7万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0649924&HistoricalAwards=false
• 关键词: IDBR; Development; System; Measuring; Dynamic

This award is for the development of short-lived radioisotope tracing instrumentation in order to track in real time the assimilation, translocation, and export of materials within and between living plants under controlled environmental conditions. The Radioisotope Tracing with Environmental Controls (RTEC) system is based on the use of short-lived radioisotopes and gamma-ray coincidence counting techniques. Coincidence counting is an efficient and economical method of tracing the accumulation of radioactively tagged compounds in applications where high spatial resolution is not required. The implementation of the system will utilize the plant growth facility and the nuclear laboratory at the university, which are less than 100 meters apart. This RTEC system will be used to improve the mechanistic understanding of plant physiological responses to environmental change. Nine research groups are currently involved in the collaboration. The proposed instrument will provide the capabilities for examining dynamic effects of environmental change on carbon (C) and nitrogen (N) allocation in plants. In particular, the RTEC system will enable researchers to make some of the first systematic measurements of carbon and nitrogen translocation in different plant species at the plant-soil interface and within single plants under precisely controlled environmental conditions, information that will dramatically improve understanding of the controls on plant carbon sequestration. The research enabled by the RTEC system will complement field research projects that study the effects of elevated CO2 levels on plant growth. This instrument will enable measurements that can potentially reveal the mechanisms responsible for the apparent lack of long-term carbon sequestration by mature trees that has been observed in large-scale Free Air Carbon Dioxide Enrichment experiments that are underway globally. In addition, this instrument will open opportunities for research on topics such as the dynamics of nutrient uptake and distribution (using Nitrogen-13 tagged nutrients), water absorption and transport (using both Fluorine-18 in solution and Oxygen-15 tagged water), the carbon-nitrogen balance in plant growth (using Nitrogen-13 tagged nutrients and Carbon-11 tagged CO2), and the role of microbial activities in the carbon-nitrogen cycle. In addition to its scientific benefits, this project will involve graduate and undergraduate students in frontier interdisciplinary research in biology and physics. For example, undergraduate biology and physics students will help with the assembly and testing of the gamma-ray detectors and will assist with the design, assembly and installation of the detector support structure in the growth chamber. Undergraduate students will also work on the design, installation and testing of the gas circulation loop used in the CO2 studies and with the overall system testing. Existing collaborations with physics faculty members at two regional historically black universities will encourage their use of this research instrumentation.

该奖项是为了开发短寿命放射性同位素示踪仪器，以便在受控的环境条件下，在真实的时间内跟踪活植物内和活植物之间的物质同化，转移和输出。放射性同位素示踪与环境控制（RTEC）系统基于短寿命放射性同位素和伽马射线符合计数技术的使用。符合计数是一种有效和经济的方法，在不需要高空间分辨率的应用中追踪放射性标记化合物的积累。该系统的实施将利用该大学的植物生长设施和核实验室，两者相距不到100米。 该RTEC系统将用于提高对植物对环境变化的生理反应的机制理解。目前有9个研究小组参与了合作。拟议的仪器将提供检查环境变化对植物中碳（C）和氮（N）分配的动态影响的能力。特别是，RTEC系统将使研究人员能够在精确控制的环境条件下对不同植物物种在植物-土壤界面和单个植物内的碳和氮转移进行首次系统测量，这些信息将大大提高对植物碳封存控制的理解。RTEC系统支持的研究将补充研究CO2水平升高对植物生长影响的实地研究项目。该仪器将能够进行测量，从而有可能揭示在全球正在进行的大规模自由空气二氧化碳富集实验中观察到的成熟树木明显缺乏长期碳封存的机制。此外，这一工具将为研究养分吸收和分配动态等专题提供机会（使用氮-13标记的营养素），水分吸收和运输（使用溶液中的氟-18和氧-15标记的水），植物生长中的碳-氮平衡（使用氮-13标记的营养素和碳-11标记的CO2），以及微生物活动在碳-氮循环中的作用。除了其科学效益，该项目将涉及研究生和本科生在生物学和物理学的前沿跨学科研究。例如，生物学和物理学本科生将帮助组装和测试伽马射线探测器，并协助设计、组装和安装生长室中的探测器支撑结构。本科生还将从事CO2研究中使用的气体循环回路的设计，安装和测试以及整体系统测试。现有的合作与物理教师在两个地区历史上的黑人大学将鼓励他们使用这种研究仪器。