NSF Minority Postdoctoral Research Fellowship for FY 2009

本行动根据2009年美国复苏与再投资法案（公法111-5）资助国家科学基金会2009年度少数民族博士后研究奖学金。该奖学金支持奖学金获得者在主办实验室的研究和培训计划，该奖学金获得者还提出了扩大生物学参与的计划。Angelia Seyfferth的研究和培训计划的标题是“田间水稻（Oryza sativa L.）中砷吸收和转化的生理机制”。该奖学金支持的研究和培训是在斯坦福大学进行的。Scott Fendorf， Devaki Bhaya和Peter Vitousek。人们担心，南亚和东南亚地下水的砷污染正在造成人类历史上最大的暴露，那里有超过1.4亿人正在饮用砷含量达到危险水平的水。通过食用用这种受污染的地下水灌溉的水稻而暴露于砷的重要性可能与通过饮用水暴露于砷的重要性相等或更大，特别是对依靠大米维持生计的人口而言。植物对各种化学形式的砷的处理方式不同。因此，了解进入水稻根系的不同机制以及随后向可食用谷物的转运是很重要的。在田间种植的水稻根际和不同植物组分中，哪种化学形式占主导地位目前尚不清楚。本研究项目的总体目标是利用x射线吸收光谱和放射性标记砷的质量平衡来阐明水稻对砷的吸收、积累和植株转化的主要机制。具体的培训目标是获得生物学、化学、地质学和环境科学领域的现场经验，并学习新的分析工具和技术，以实现既定的科学目标。更广泛的影响包括向柬埔寨当地稻农伸出援手，并指导研究生和本科生。

This action funds an NSF Minority Postdoctoral Research Fellowship for FY 2009 and is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Angelia Seyfferth is "Physiological Mechanisms Underlying Arsenic Uptake and Transformation in Field-Grown Rice (Oryza sativa L.)." The research and training supported by this fellowship is being conducted at Stanford University under the sponsorships of Drs. Scott Fendorf, Devaki Bhaya, and Peter Vitousek.It is feared that arsenic (As) contamination of groundwaters in southern and southeastern Asia is causing the largest exposure in human history where more than 140 million people are drinking water with hazardous levels of arsenic. Exposure to arsenic through consumption of rice irrigated with this contaminated groundwater may be of equal or greater importance than exposure through drinking water, particularly for populations that rely on rice for sustenance. Plants do not deal with the various chemical forms of arsenic in the same way. Therefore, it is important to understand the different mechanisms of entry into rice roots and subsequent translocation toward the edible grain. Which chemical form is predominant in the rhizosphere of field-grown rice and within different plant fractions is presently unresolved. The overall goal of this research project is to elucidate the predominant mechanism of arsenic uptake, accumulation, and in planta transformation within field-grown rice utilizing both X-ray absorption spectroscopy and mass-balance with radiolableled arsenic. The specific training objectives are to gain field experience at the interface of biology, chemistry, geology, and environmental science and to learn new analytical tools and techniques to achieve the stated scientific goals. The broader impacts include outreach to local Cambodian rice farmers and mentoring graduate and undergraduate students.