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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Opportunities for Improvement in FRMAC's Assessment Method for Ingestion of Contaminated Crops

This report provides recommendations to improve the assessment method of the Federal Radiological Monitoring and Assessment Center (FRMAC) for the ingestion of crops contaminated with radionuclides. The current FRMAC method of calculating investigation levels (ILs) and crop derived response levels (DRLs) is detailed. Recommended modifications to these calculations are presented based on the following aspects: handling radionuclide mixtures, no immediate equilibrium, washing of contaminated crops, and updated dietary intake rates.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Deciphering Time-Dependent DNA Damage Complexity, Repair, and Oxygen Tension: A Mechanistic Model for FLASH-Dose-Rate Radiation Therapy

Irradiation with ultrahigh dose rates (FLASH) has reemerged as a promising radiation therapy approach to effectively lower potential damage burden on normal tissue without sacrificing tumor control. However, the large number of recent FLASH studies have been conducted under vastly different experimental conditions and circumstances (ie, investigated biological endpoint, radiation quality, and environmental oxygen level), with unverified biological mechanisms of action and unexplored interplay effect of the main dependencies. To facilitate radiobiological investigation of FLASH phenomena and assessment of clinical applicability, we present an extension of the mechanistic radiobiological model “UNified and VERSatile bio response Engine” (UNIVERSE).

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2021

Correlations Between Panoramic Imagery and Gamma-Ray Background in an Urban Area

When searching for radiological sources in an urban area, a vehicle-borne detector system will often measure complex, varying backgrounds primarily from natural gamma-ray sources. Much work has been focused on developing spectral algorithms that retain sensitivity and minimize the false-positive rate even in the presence of such spectral and temporal variability. However, information about the environment surrounding the detector system might also provide useful clues about the expected background, which if incorporated into an algorithm, could improve performance. Recent work has focused on extensive measuring and modeling of urban areas with the goal of understanding how these complex backgrounds arise. This work presents an analysis of panoramic video images and gamma-ray background data collected in Oakland, California, by the radiological multisensor analysis platform (RadMAP) vehicle. Features were extracted from the panoramic images by semantically labeling the images and then convolving the labeled regions with the detector response. A linear model was used to relate the image-derived features to gamma-ray spectral features obtained using nonnegative matrix factorization (NMF) under different regularizations. Here we find some gamma-ray background features correlate strongly with image-derived features that measure the response-adjusted solid angle subtended by sky and buildings, and we discuss the implications for the development of future, contextually aware detection algorithms.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2022

Utility of Circulating MicroRNA-150 for Rapid Evaluation of Bone Marrow Depletion After Radiation and Efficiency of Bone Marrow Reconstitution

Total body irradiation (TBI) is a common myeloablative preparative regimen used in acute myeloid and lymphoblastic leukemia patients before allogenic hematopoietic stem cell transplantation (HSCT). The inefficient clearance of tumor cells and radiation-induced toxicity to normal tissues is attributed to relapse and morbidity in a significant fraction of patients. Developing biomarkers that indicate an individual's physiological response to radiation will allow personalized treatment and follow-up. We investigated the utility of circulating microRNA150-5p (miR150) for evaluation of radiation dose response.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

Radiological Considerations Supporting the American Medical Isotope Producer Niowave

This report provides a summary of work performed by Savannah River National Laboratory (SRNL) during FY22 in support of Niowave, an American Medical Isotope Production (AMIP) facility. SRNL served in a technical support role, funded by NA-231, supporting Niowave in the beginning of non radiological functional testing of their airport facility in FY22. Through this agreement, SRNL provides Niowave access to subject matter experts (SMEs) for questions that may arise during the drafting of engineering plans, facility policies, and/or response procedures. This report summarizes discussions between SRNL and Niowave about guidance concerning issues with the floor of the hot cells, dispersible removable contamination (beta emitting fission product), hot cell operation specifically utilization of cameras or mirrors, and the process for removing contaminated waste from the hot cell. Lessons learned and other various resources provided to Niowave by SRNL during FY22 are referenced in this report. This work was funded through NNSA’s Office of Material Management and Minimization, Conversion Office (NA-231).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

Financial Exposure After a Sealed-Source Release: Insurance Limits, Federal Cost Pathways, and Implications for Gamma Irradiator Substitution

This report assesses whether private insurance and existing federal authorities would likely provide meaningful financial protection to private operators of self-shielded gamma irradiators after a major sealed-source release. It does not answer this question quantitatively because publicly observable data on premiums, limits, uptake, and claims outcomes for this risk class appear sparse. Instead, it uses a qualitative structural analysis based on prior literature, review of relevant federal authorities, limited observable insurance-market evidence, expert outreach, and historical analogs. The analysis finds that available public and private mechanisms do not combine into a clear, dependable, or readily verifiable compensation structure for ordinary private sealed-source operators. Institutions therefore should not assume that either insurance or government response will make them financially whole after a severe incident. Source reduction and replacement remain more dependable than post-event financial mechanisms for reducing institutional exposure and broader radiological risk.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2020

Rewilding of Fukushima's human evacuation zone

There is substantial interest in understanding the ecological impacts of the nuclear accidents at the Chernobyl and Fukushima Daiichi nuclear power plants. However, population‐level data for large mammals have been limited, and there remains much speculation regarding the status of wildlife species in these areas. Using a network of remote cameras placed along a gradient of radiological contamination and human presence, we collected data on population‐level impacts to wildlife (that is, abundance and occupancy patterns) following the 2011 Fukushima Daiichi nuclear accident. We found no evidence of population‐level impacts in mid‐ to large‐sized mammals or gallinaceous birds, and show several species were most abundant in human‐evacuated areas, despite the presence of radiological contamination. These data provide unique evidence of the natural rewilding of the Fukushima landscape following human abandonment, and suggest that if any effects of radiological exposure in mid‐ to large‐sized mammals in the Fukushima Exclusion Zone exist, they occur at individual or molecular scales, and do not appear to manifest in population‐level responses.

Lyons, Phillip C.↗
DOE OSTI2021

Potentiating Antitumor Efficacy Through Radiation and Sustained Intratumoral Delivery of Anti-CD40 and Anti-PDL1

Mounting evidence demonstrates that combining radiation therapy (RT) with immunotherapy can reduce tumor burden in a subset of patients. However, conventional systemic delivery of immunotherapeutics is often associated with significant adverse effects, which force treatment cessation. The aim of this study was to investigate a minimally invasive therapeutics delivery approach to improve clinical response while attenuating toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

Drones for Decommissioning

The U.S. Nuclear Regulatory Commission has responsibility for regulating the safe decommissioning of facilities and sites to meet the License Termination Rule in 10 Code of Federal Regulations (CFR) Part 20, Standards for Protection Against Radiation, Subpart E “Radiological Criteria for License Termination.” Decommissioning is performed in accordance with 10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities, as part of license termination (§50.82) and release of the facility or site for unrestricted use (§50.83). The guidance currently demonstrates the minimum requirements and necessary conditions for conducting radiological surveys by a person carrying a radiation detector(s). The Pacific Northwest National Laboratory (PNNL) evaluated the use of an unoccupied aerial vehicle (UAV) to conduct radiological surveys that could be used in decommissioning to potentially reduce time, cost, and worker safety compared to current survey methods. The objective of this project was to evaluate the performance and limitations of a UAV to support a decommissioning radiological survey and compare it to a radiological survey conducted by a human. The primary research questions of interest evaluated were: 1. Did observed UAV paths differ from human paths and, if so, how much? 2. Did survey path deviation affect survey results and, if so, how? 3. Were radiological measurements from human and UAV surveys significantly different? To answer these research questions, an experimental field was set up at PNNL’s 3440 test track, and it included radiological sources commonly surveyed during decommissioning: cobalt-60 (Co-60), cesium-137 (Cs-137), and americium-241 (Am-241). Nine check sources (three each of Am-241, Cs-137, and Co-60) with activities ranging from 3.54 µCi to 39.34 µCi were set over a path that also included an area for measuring background radiation. An Aurelia X6 UAV coupled with a GPS and lidar unit was used to conduct the radiological surveys. UAV and human surveys were conducted using two different NaI(Tl) scintillation radiation detectors (2 in. × 2 in. Ludlum, Inc. and 2 in. × 0.04 in. Alpha Spectra, Inc.) at a travel velocity of approximately 0.2 m/s at a low (15–40 cm median altitude) or high (87–105 cm median altitude) survey altitude. Since the survey velocity and altitude parameters were atypical for normal UAV operations, testing was done prior to conducting the radiological surveys to establish airworthiness, evaluate the navigation system, and establish flight control. Human and UAV surveys were paired according to the detector type and altitude regime to compare the survey data. The results of this proof-of-concept research determined that the UAV and human surveys followed similar survey paths and detected the radiological sources with no significant statistical difference (in 33 out of 36 surveys). However, further research is needed prior to deploying UAVs for decommissioning surveys.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2022

Radiological Dispersal Device (RDD) Recovery Guidance: After Action Report from Pilots - Responding to Feedback from Pilots Reviewing RDD Recovery Guidance

The goal of this After Action report is to utilize feedback from the pilot participants to improve the guidance for responding to radiological dispersal device (RDD) events, which can include deliberate acts to release radioactive materials into the environment using explosives or other means or accidental releases (e.g., release from a medical isotope source). This longer-term recovery guidance is an extension of the initial response guidance that was released in a 2017 interagency report called RDD Response Guidance: Planning for the First 100 Minutes. Recovery teams reviewed the longer-term recovery guidance during pilot sessions that were held in Harris County, Texas (March 8-10, 2022) and Seattle, Washington (May 2-3, 2022). The pilot teams reviewed the RDD Recovery Guidance Presentation, which contains a summary of the more detailed RDD Recovery Guidance draft document. The feedback from both pilots was grouped and binned into unique themes (e.g., “checkpoint challenges”) that align with the recovery missions and tactics that they reviewed. PNNL authors of the recovery guidance then prepared responses that describe how they recommend addressing the feedback for each theme. The responses typically included recommendation plans for improving the guidance document, but also described when no changes are needed because the guidance already contains the suggested improvement. These pilot recommendations will be brought to the interagency team to finalize plans for updating and improving recovery guidance materials.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2021

Executive Summary of the American Radium Society Appropriate Use Criteria for Operable Esophageal and Gastroesophageal Junction Adenocarcinoma: Systematic Review and Guidelines

Limited guidance exists regarding the relative effectiveness of treatment options for nonmetastatic, operable patients with adenocarcinoma of the esophagus or gastroesophageal junction (GEJ). In this systematic review, the American Radium Society (ARS) gastrointestinal expert panel convened to develop Appropriate Use Criteria (AUC) evaluating how neoadjuvant and/or adjuvant treatment regimens compared with each other, surgery alone, or definitive chemoradiation in terms of response to therapy, quality of life, and oncologic outcomes.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2021

Coadministration of a Clinically Relevant Dexamethasone Dosage With Ablative Radiation Therapy Reduces Peripheral Lymphocytes But Does Not Alter In Vivo Intratumoral Lymphocyte Phenotype or Inhibit Efficacy of Radiation Therapy in a Murine Colorectal Tumor Model

Dexamethasone is commonly given during radiation therapy (RT) to manage toxicities. Our study examines if dexamethasone coadministration with RT inhibits the RT-induced antitumor T cell response in mouse.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

Niowave Ancillary Systems – FY21: In Partial Fulfillment of the Deliverable Requirement for Niowave Ancillary Systems Support by LANL

Niowave Inc. produces medical radioisotopes within the US. Lead-bismuth eutectic (LBE) is irradiated using an electron beam to produce neutrons that are used in the production of Molybdenum-99 (Mo-99). The medical community relies on a steady supply of Mo-99 which is primarily used in medical diagnostic imaging. The irradiation of LBE results in high temperatures within the molten metal, this work focusses on the design of ancillary systems associated with the liquid metal system. The LBE is initially at a temperature of 200°C and flows over a steel plate to create a waterfall. The electron beam is then aimed at the waterfall to generate neutrons. The peak temperatures of the LBE post irradiation depend on the beam energy of the LINAC. For a 15 MeV and 20 kW beam, the temperatures can range between 300°C and 350°C. The LBE is cycled through the system to create a closed loop that requires the post-irradiation LBE to be cooled back to 200°C. This work focuses on the heat exchanger and condenser system responsible for the cooling of the post-irradiation LBE.

36 MATERIALS SCIENCE↗