CORE--NEUTRON ACTIVATION FACILITY

核心单元B将为项目资助(PPG)研究人员提供三项服务：H、C、N、O、Ca、P、Na和C1的高精度体内中子活化(IVNA)分析测量和K的全身计数；IVNA结果的专家协助解释和分析；以及新仪器设计和开发的物理咨询。在PPG I期间，开发了用于IVNA高精度人体成分测量的仪器，并配备了最先进的硬件。在PPG II期间，分析策略的后续改进扩大了研究对象的范围。通过使用新的和改进的模体，并通过实施蒙特卡罗代码(MCNP)对不同的身体形态和身高进行广泛的模拟，IVNA设备的测量精度得到了进一步提高。在此期间，随着结果的公布，与贝勒的研究人员进行了广泛的钙校准和交叉校准，并与核心单位A的研究人员进行了全身钾(TBK)的交叉校准。用较新的系统替换较旧的计算机使得能够从早期的软件环境转移到当代的操作系统。这些改进加上基本操作的升级，使得使用稳定的系统每周可以例行测量多达6名患者。在拟议的PPG III期间，将继续为临床研究项目提供核心支持，并将实施重要的新举措，包括：在项目3中测量肥胖患者的总胆红素和钙的新校准；与核心A建立部分/区域体内氮与总氮的相关性；为三个激活设施中的每个设施创建独立的MCNP输入文件，描述由BOMAB模型模拟的人体；并设计伽玛核共振吸收测量系统，用于体内元素成像。核心的活动符合能源部的任务，即开发新技术，在开发和测试阶段后将这些系统转移到合作实验室，并保持最先进的系统作为国家和内部参考标准。

Core Unit B will provide Program Project Grant (PPG) investigators with three services: high precision whole-body in vivo neutron activation (IVNA) analysis measurements of H, C, N, O, Ca, P, Na, and C1, and whole-body counting for K; expert assistance with interpretation and analysis of IVNA results; and physics consultations for new instrument design and development. Instrumentation for high precision measurements of body composition by IVNA were developed and equipped with state-of-the-art hardware during PPG I. Subsequent improvements in the analytical strategies extended the range of subjects that were included in the studies during PPG II measurement precisions of the IVNA facilities were further improved using new and improved phantoms and by implementing a Monte Carlo code (MCNP) to carry out extensive simulations for different body configurations and stature. During this period extensive calibrations and cross-calibrations with investigators at Baylor for Ca and with investigators at Core Unit A for total body potassium (TBK), were carried out with publication of results. Replacement of older computers with newer systems enabled transfer from an early software environment to contemporary operating systems. These improvements along with basic operations upgrades allowed measurement routinely of up to six patients per week with stabilized systems. Core support during the proposed PPG III for clinical research projects will continue and important new initiatives will be instituted, including: new calibrations for measuring TBK and Ca in obese patients in Project 3; correlation of partial/regional body nitrogen to total body nitrogen with Core A; creation of independent MCNP input files that describe the human body as simulated by a BOMAB phantom for each of the three activation facilities; and design of a Gamma Nuclear Resonance Absorptiometry system for elemental imaging in vivo. The Core's activities are consistent with the Department of Energy's mandate to develop novel technologies, to transfer these systems to cooperating laboratories following their developing and testing phase, and to maintain state-of-the art systems for use as national and internal reference standards.