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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Modern Outcomes of Inflammatory Breast Cancer

Purpose: To report contemporary outcomes for inflammatory breast cancer (IBC) patients treated in the modern era of trastuzumab and taxane-based chemotherapy. Methods and Materials: We retrospectively reviewed the charts of 104 patients with nonmetastatic IBC treated between January 2000 and December 2009. Patients who received chemotherapy, surgery, and radiation therapy were considered to have completed the intended therapy. Kaplan-Meier curves estimated locoregional control (LRC), distant metastases-free survival (DMFS), and overall survival. Results: The median follow-up time was 34 months; 57 (55%) patients were estrogen receptor progesterone receptor (ER/PR) negative, 34 (33%) patients were human epidermal growth factor receptor 2 (her2)/neu amplified, and 78 (75%) received definitive postoperative radiation. Seventy-five (72%) patients completed all of the intended therapy, of whom 67 (89%) received a taxane and 18/28 (64%) of her2/neu-amplified patients received trastuzumab. For the entire cohort, the 5-year rates of overall survival, LRC, and DMFS were 46%, 83%, and 44%, respectively. The ER/PR-negative patients had a 5-year DMFS of 39% vs. 52% for ER/PR-positive patients (p = 0.03). The 5-year DMFS for patients who achieved a pathologic complete response compared with those who did not was 83% vs. 44% (p < 0.01). Those patients who received >60.4 Gy (n = 15) to the chest wall had a 5-year LRC rate of 100% vs. 83% for those who received 45 to 60.4 Gy (n = 49; p = 0.048). On univariate analysis, significant predictors of DMFS included achieving a complete response to neoadjuvant chemotherapy (hazard ratio [HR] = 5.8; 95% confidence interval [CI] = 1.4-24.4; p = 0.02) and pathologically negative lymph nodes (HR = 4.1; 95% CI = 1.4-11.9; p < 0.01), but no factor was significant on multivariate analysis. Conclusions: For IBC patients, the rate of distant metastases is still high despite excellent local control, particularly for patients who received >60.4 Gy to the chest wall. Despite the use of taxanes and trastuzumab, outcomes remain modest, particularly for those with ER/PR-negative disease and those without a pathologic complete response.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Association of Clinical Response and Long-term Outcome Among Patients With Biopsied Orbital Pseudotumor Receiving Modern Radiation Therapy

Purpose: To retrospectively evaluate institutional outcomes for patients treated with modern radiation therapy (RT) for biopsied orbital pseudotumor (OP). Methods and Materials: Twenty patients (26 affected orbits) with OP were treated with RT between January 2002 and December 2011. All patients underwent biopsy with histopathologic exclusion of other disease processes. Sixteen patients (80%) were treated with intensity modulated RT, 3 (15%) with opposed lateral beams, and 1 (5%) with electrons. Median RT dose was 27 Gy (range 25.2-30.6 Gy). Response to RT was evaluated at 4 months post-RT. Partial response (PR) was defined as improvement in orbital symptoms without an increase in steroid dose. Complete response (CR) 1 and CR 2 were defined as complete resolution of orbital symptoms with reduction in steroid dose (CR 1) or complete tapering of steroids (CR 2). The median follow-up period was 18.6 months (range 4-81.6 months). Results: Seventeen patients (85%) demonstrated response to RT, with 7 (35%), 1 (5%), and 9 (45%) achieving a PR, CR 1, and CR 2, respectively. Of the 17 patients who had ≥PR at 4 months post-RT, 6 (35%) experienced recurrence of symptoms. Age (>46 years vs ≤46 years, P=.04) and clinical response to RT (CR 2 vs CR 1/PR, P=.05) were significantly associated with pseudotumor recurrence. Long-term complications were seen in 7 patients (35%), including 4 with cataract formation, 1 with chronic dry eye, 1 with enophthalmos, and 1 with keratopathy. Conclusions: RT is an effective treatment for improving symptoms and tapering steroids in patients with a biopsy supported diagnosis of OP. Older age and complete response to RT were associated with a significantly reduced probability of symptom recurrence. The observed late complications may be related to RT, chronic use of steroids/immunosuppressants, medical comorbidities, or combination of factors.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Results of a 5-Week Schedule of Modern Total Skin Electron Beam Radiation Therapy

Purpose: To report the outcomes of a 5-week schedule of total skin electron beam radiation therapy (TSEB) for mycosis fungoides (MF). Methods: Over 5 years, 41 patients with confirmed MF were treated with a modern TSEB technique delivering 30 Gy in 20 fractions over 5 weeks to the whole skin surface. Data were collected prospectively and entered into the skin tumor unit research database. Skin modified skin weighted assessment tool score data were collected to determine response, duration of response, survival, and toxicity. The outcomes were analyzed according to the patient's stage before TSEB, prognostic factors, and adjuvant treatments. Results: Seventeen patients were stage 1B, 19 were stage IIB, 3 were stage III, and 2 were stage IV. The overall response rate was 95%, with a complete response rate of 51%. Seventy-six percent of patients had relapsed at median follow-up of 18 months. The median time to relapse was 12 months, to systemic therapy was 15 months, and to modified skin weighted assessment tool progression above baseline was 44 months. The complete response rate was 59% in stage IB and 47% in stage IIB patients. The median time to skin relapse was longer in stage IB compared with stage IIB, 18 months versus 9 months. The median time to systemic therapy was longer in stage IB compared with stage IIB, >56 months versus 8 months. The median overall survival was 35 months: >56 months for stage IB, 25 months for stage IIB, 46 months for stage III, and 23.5 months for stage IV. Fifteen patients received adjuvant psoralen + ultraviolet A treatment with no difference seen in the time to relapse. Conclusions: This 5-week schedule of TSEB for MF has a high response rate with comparable duration of response to other regimens. Future studies are needed to find adjuvant and combination treatments to improve the duration of response.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Doses to Carotid Arteries After Modern Radiation Therapy for Hodgkin Lymphoma: Is Stroke Still a Late Effect of Treatment?

Purpose: Hodgkin lymphoma (HL) survivors are at an increased risk of stroke because of carotid artery irradiation. However, for early-stage HL involved node radiation therapy (INRT) reduces the volume of normal tissue exposed to high doses. Here, we evaluate 3-dimensional conformal radiation therapy (3D-CRT), volumetric-modulated arc therapy (VMAT), and proton therapy (PT) delivered as INRT along with the extensive mantle field (MF) by comparing doses to the carotid arteries and corresponding risk estimates. Methods and Materials: We included a cohort of 46 supradiaphragmatic stage I-II classical HL patients. All patients were initially treated with chemotherapy and INRT delivered as 3D-CRT (30 Gy). For each patient, we simulated MF (36 Gy) and INRT plans using VMAT and PT (30 Gy). Linear dose-response curves for the 20-, 25-, and 30-year risk of stroke were derived from published HL data. Risks of stroke with each technique were calculated for all patients. Statistical analyses were performed with repeated measures analysis of variance. Results: The mean doses to the right and left common carotid artery were significantly lower with modern treatment compared with MF, with substantial patient variability. The estimated excess risk of stroke after 20, 25, and 30 years was 0.6%, 0.86%, and 1.3% for 3D-CRT; 0.67%, 0.96%, and 1.47% for VMAT; 0.61%, 0.96%, and 1.33% for PT; and 1.3%, 1.72%, and 2.61% for MF. Conclusions: INRT reduces the dose delivered to the carotid arteries and corresponding estimated risk of stroke for HL survivors. Even for the subset of patients with lymphoma close to the carotid arteries, the estimated risk is low.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Breast Cancer Laterality Does Not Influence Survival in a Large Modern Cohort: Implications for Radiation-Related Cardiac Mortality

Objectives: Radiation therapy for left-sided breast cancer has been associated with an elevated risk of cardiac mortality, based on studies predating treatment planning based on computed tomography. This study assessed the impact of tumor laterality on overall survival (OS) in a large cohort treated with modern techniques, to indirectly determine whether left-sided treatment remains associated with increased cardiac mortality. Methods and Materials: Patients treated for breast cancer with breast conserving surgery and adjuvant external beam radiation therapy were identified in the National Cancer Database, and OS was compared based on tumor laterality using Kaplan-Meier analysis. Separate analyses were performed for noninvasive and invasive carcinoma and for breast-only and breast plus regional nodal radiation therapy. Multivariate regression analysis of OS was performed with demographic, pathologic, and treatment variables as covariates to adjust for factors associated with breast cancer–specific survival. Results: We identified 344,831 patients whose cancer was diagnosed from 1998 to 2006 with a median follow-up time of 6.04 years (range, 0-14.17 years). Clinical, tumor, and treatment characteristics were similar between laterality groups. Regional nodal radiation was used in 14.2% of invasive cancers. No OS difference was noted based on tumor laterality for patients treated with breast-only (hazard ratio [HR] 0.984, P=.132) and breast plus regional nodal radiation therapy (HR 1.001, P=.957). In multivariate analysis including potential confounders, OS was identical between left and right sided cancers (HR 1.002, P=.874). No significant OS difference by laterality was observed when analyses were restricted to patients with at least 10 years of follow-up (n=27,725), both in patients treated with breast-only (HR 0.955, P=.368) and breast plus regional nodal radiation therapy (HR 0.859, P=.155). Conclusions: Radiation therapy for left-sided breast cancer does not appear to increase the risk of death in this national database relative to right-sided tumors. Consequently, radiation therapy–induced cardiac disease may be less prominent than previously demonstrated.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Total Skin Electron Therapy for Cutaneous T-Cell Lymphoma Using a Modern Dual-Field Rotational Technique

Purpose: To report our experience with rotational total skin electron irradiation (RTSEI) in cutaneous T-cell lymphoma (CTCL), and to examine response by disease stage and race. Methods and Materials: We reviewed our outcomes for 68 CTCL patients who received RTSEI (≥30 Gy) from 2000 to 2013. Primary outcomes were complete clinical response (CCR), recurrence-free survival (RFS), and overall survival (OS). Using log–rank tests and Cox proportional hazards, OS and RFS were compared across tumor stages at time of RTSEI with further racial subgroup analysis. Results: Median age at diagnosis and at time of radiation was 52 and 56 years, respectively. Median follow-up was 5.1 years, 49% were African American, and 49% were female. At time of treatment, 18, 37, and 13 patients were T stage 2, 3, and 4, respectively. At 6 weeks after RTSEI, overall CCR was 82% (88%, 83%, and 69% for T2, T3, and T4, respectively). Median RFS was 11 months for all patients and 14, 10, and 12 months for stage T2, T3, and T4, respectively. Tumor stage was not associated with RFS or CCR. Maintenance therapy after RTSEI was associated with improved RFS in both crude and multivariable analysis, controlling for T stage. Median OS was 76 months (91 and 59 months for T3 and T4, respectively). With the exception of improved OS in African Americans compared with whites at stage T2, race was not associated with CCR, RFS, or OS. Conclusions: These results represent the largest RTSEI clinical outcomes study in the modern era using a dual-field rotational technique. Our observed response rates match or improve upon the standard set by previous outcome studies using conventional TSEI techniques, despite a large percentage of advanced CTCL lesions in our cohort. We found that clinical response after RTSEI did not seem to be affected by T stage or race.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Modern Radiation Therapy for Primary Cutaneous Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

Primary cutaneous lymphomas are a heterogeneous group of diseases. They often remain localized, and they generally have a more indolent course and a better prognosis than lymphomas in other locations. They are highly radiosensitive, and radiation therapy is an important part of the treatment, either as the sole treatment or as part of a multimodality approach. Radiation therapy of primary cutaneous lymphomas requires the use of special techniques that form the focus of these guidelines. The International Lymphoma Radiation Oncology Group has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the International Lymphoma Radiation Oncology Group steering committee on the use of radiation therapy in primary cutaneous lymphomas in the modern era.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Modern Radiation Therapy for Extranodal Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Risk of Pathologic Upgrading or Locally Advanced Disease in Early Prostate Cancer Patients Based on Biopsy Gleason Score and PSA: A Population-Based Study of Modern Patients

Purpose: Radiation oncologists rely on available clinical information (biopsy Gleason score and prostate-specific antigen [PSA]) to determine the optimal treatment regimen for each prostate cancer patient. Existing published nomograms correlating clinical to pathologic extent of disease were based on patients treated in the 1980s and 1990s at select academic institutions. We used the Surveillance, Epidemiology, and End Results (SEER) database to examine pathologic outcomes (Gleason score and cancer stage) in early prostate cancer patients based on biopsy Gleason score and PSA concentration. Methods and Materials: This analysis included 25,858 patients whose cancer was diagnosed between 2010 and 2011, with biopsy Gleason scores of 6 to 7 and clinical stage T1 to T2 disease, who underwent radical prostatectomy. In subgroups based on biopsy Gleason score and PSA level, we report the proportion of patients with pathologically advanced disease (positive surgical margin or pT3-T4 disease) or whose Gleason score was upgraded. Logistic regression was used to examine factors associated with pathologic outcomes. Results: For patients with biopsy Gleason score 6 cancers, 84% of those with PSA <10 ng/mL had surgical T2 disease with negative margins; this decreased to 61% in patients with PSA of 20 to 29.9 ng/mL. Gleason score upgrading was seen in 43% (PSA: <10 ng/mL) to 61% (PSA: 20-29.9 ng/mL) of biopsy Gleason 6 patients. Patients with biopsy Gleason 7 cancers had a one-third (Gleason 3 + 4; PSA: <10 ng/mL) to two-thirds (Gleason 4 + 3; PSA: 20-29.9 ng/mL) probability of having pathologically advanced disease. Gleason score upgrading was seen in 11% to 19% of patients with biopsy Gleason 4 + 3 cancers. Multivariable analysis showed that higher PSA and older age were associated with Gleason score upgrading and pathologically advanced disease. Conclusions: This is the first population-based study to examine pathologic extent of disease and pathologic Gleason score upgrading based on clinically available information in modern patients. These data inform the selection of radiation therapy strategies and an understanding of whether prostatectomy alone is likely to be curative for patients with early prostate cancers.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

In the Modern Treatment Era, Is Breast Conservation Equivalent to Mastectomy in Women Younger Than 40 Years of Age? A Multi-Institution Study

Purpose: Mastectomy is often recommended for women ≤40 years of age with breast cancer, as young women were under-represented in the landmark trials comparing breast conservation therapy (BCT) to mastectomy. We hypothesized that, in the modern treatment era, BCT and mastectomy result in equivalent local control rates in young women. Methods and Materials: Breast cancer cases arising between 1975 and 2013 in women ≤40 years old were collected from the tumor registries of 2 large healthcare systems in Utah. Kaplan-Meier estimates and Cox proportional hazards models were used to analyze freedom from locoregional recurrence (FFLR), overall survival (OS), and relapse-free survival (RFS). Results: This analysis identified 853 BCT candidates. A comparison of BCT to mastectomy after 2000 showed FFLR, RFS, and OS were all similar. Rate for FFLR at 10 years was 94.9% versus 92.1% for BCT and mastectomy, respectively (P=.57). For women whose cancer was diagnosed after 2000, who received BCT, FFLR and RFS rates were improved compared to those whose cancer was diagnosed prior to 2000 (P<.05), whereas OS (P=.46) rates were similar. Among those who underwent mastectomy, FFLR, OS, and RFS were significantly improved (P<.05) with diagnosis after 2000. Conclusions: FFLR rates for young women, ≤40 years of age, have significantly improved for BCT and mastectomy over time. If patients were treated after 2000, BCT appears to be safe and equivalent to mastectomy at 10 years in terms of FFLR, OS, and RFS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Modern Radiation Therapy and Cardiac Outcomes in Breast Cancer

Purpose: Adjuvant radiation therapy, which has proven benefit against breast cancer, has historically been associated with an increased incidence of ischemic heart disease. Modern techniques have reduced this risk, but a detailed evaluation has not recently been conducted. The present study evaluated the effect of current radiation practices on ischemia-related cardiac events and procedures in a population-based study of older women with nonmetastatic breast cancer. Methods and Materials: A total of 29,102 patients diagnosed from 2000 to 2009 were identified from the Surveillance, Epidemiology, and End Results–Medicare database. Medicare claims were used to identify the radiation therapy and cardiac outcomes. Competing risk models were used to assess the effect of radiation on these outcomes. Results: Patients with left-sided breast cancer had a small increase in their risk of percutaneous coronary intervention (PCI) after radiation therapy—the 10-year cumulative incidence for these patients was 5.5% (95% confidence interval [CI] 4.9%-6.2%) and 4.5% (95% CI 4.0%-5.0%) for right-sided patients. This risk was limited to women with previous cardiac disease. For patients who underwent PCI, those with left-sided breast cancer had a significantly increased risk of cardiac mortality with a subdistribution hazard ratio of 2.02 (95% CI 1.23-3.34). No other outcome, including cardiac mortality for the entire cohort, showed a significant relationship with tumor laterality. Conclusions: For women with a history of cardiac disease, those with left-sided breast cancer who underwent radiation therapy had increased rates of PCI and a survival decrement if treated with PCI. The results of the present study could help cardiologists and radiation oncologists better stratify patients who need more aggressive cardioprotective techniques.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Role of Internal Mammary Node Radiation as a Part of Modern Breast Cancer Radiation Therapy: A Systematic Review

Purpose: Despite data from multiple randomized trials, the role of internal mammary lymph node irradiation as a part of regional nodal irradiation (IMLN RT–RNI) remains unanswered. Recent noteworthy data and modern RT techniques might identify a subset of patients who will benefit from IMLN RT–RNI, lending insight into the balance between improved outcomes and acceptable toxicity. We evaluated the current role of IMLN RT–RNI by analyzing randomized, prospective, and retrospective data. Methods and Materials: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a review of the published data was performed using PubMed to evaluate published studies from 1994 to 2015. The information evaluated included the number of patients, follow-up period, technical aspects of RT, and outcomes (clinical outcomes, complications/toxicity). Results: We included 16 studies (4 randomized, 4 nonrandomized, 7 retrospective, and 1 meta-analysis). Although older randomized trials failed to show differences in clinical outcomes or toxicity with IMLN RT–RNI, recent randomized data suggest the potential for improved outcomes, including overall survival, with IMLN RT–RNI. Furthermore, nonrandomized data have suggested a potential benefit for central tumors with IMLN RT–RNI. Although recent data have suggested a potential increase in pulmonary complications with IMLN RT–RNI with the use of advanced radiation techniques, toxicity rates remain low with limited cardiac toxicity data available. Conclusions: Increasing data from recent randomized trials support the use of IMLN RT–RNI. IMLN RT can be considered based on the inclusion of IMLN RT as a part of RNI in recent trials and the inclusion criteria from IMLN RT–RNI trials and for patients with central or medial tumors and axillary disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2026

Re-evaluating probable maximum precipitation estimates: sensitivity to transposition domains and storm rotation using modern datasets

This study examines the sensitivity of Probable Maximum Precipitation (PMP) estimates to key methodological decisions embedded in the legacy approach adopted in the U.S. National Weather Service Hydrometeorological Reports No. 51 and No. 52. Although widely used for infrastructure design and risk regulation, fundamental aspects of PMP estimation—such as storm sample size, transposition domain, maximization procedures, and storm rotation—remain poorly constrained and lack formal guidance. Using the Red Rock watershed in Iowa as a case study, and leveraging the 2002–2023 NOAA Analysis of Record for Calibration (AORC) precipitation dataset, we systematically evaluate how each methodological choice, individually and in combination, influences PMP estimates. Our findings demonstrate that PMP is not a fixed physical upper bound but rather a modeling construct shaped heavily by user-defined assumptions. Notably, PMP values derived from modern gridded rainfall datasets can be substantially higher than the legacy estimate used in the original spillway design for Red Rock Dam. Decisions regarding storm sample size, domain extent, climatological window, and particularly storm rotation all contributed to higher PMP estimates. Storm rotation alone—a loosely constrained element in the current PMP practice—can amplify PMP by more than 25%. These results reveal the lack of standardized bounds in current PMP workflows and the need for systematic sensitivity and uncertainty analysis. As PMP estimation shifts toward probabilistic approaches, incorporating physically meaningful storm attributes will be key to developing more transparent, defensible methods for dam safety and climate-resilient infrastructure.

Probable maximum precipitation↗
DOE OSTI2018

Restructuring in high burnup UO 2 studied using modern electron microscopy

Modern electron microscopy techniques were used to conduct a thorough study of an irradiated urania fuel pellet microstructure to attempt at an understanding of high burnup structure formation in this material. The fuel was irradiated at low power to high burnups in a light water reactor, proving ideal for this purpose. Examination of grain size and orientation with strict spatial selectivity across the fuel pellet radius allowed for capturing the progression of the restructuring process, from its onset to full completion. Based on this information, the polygonization mechanism was shown to be responsible for restructuring, involving formation of low-angle grain boundaries with their initiation occurring at the original high-angle grain boundaries of the as-fabricated pellet and at the gas bubble-matrix interfaces. As a result, the low-angle character of boundaries between the subdivided grains disappeared in the fully developed high burnup structure, likely due to creep deformation in the pellet.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2019

Modern nanostructured ferritic alloys: A compelling and viable choice for sodium fast reactor fuel cladding applications

Sodium fast reactor cores present a truly challenging environment for the fuel cladding and core structural materials that limit achievable fuel burnup in these systems. Modern nanostructured ferritic alloys have the potential to deliver the desired high performance characteristics where historic austenitic and ferritic/martensitic alloys fall short. Herein, a new nanostructured ferritic alloy, OFRAC ( O ak Ridge F ast R eactor A dvanced Fuel C ladding), is developed and demonstrated in cladding geometry with a length > 1 m. The alloy composition and microstructure are tailored to deliver dramatically improved strength and creep resistance. At 600 °C the ultimate tensile strength is ~600 MPa and the stress to induce a steady state strain rate of 10 -6 s -1 is 500 MPa vs. 200 MPa for traditional ferritic/martensitic alloys. A very high defect sink density was engineered in these alloys that is expected to further enhance the traditional good swelling and irradiation creep resistance of ferritic/martensitic steels. These significant improvements along with the demonstrated viability for seamless cladding production indicate that this alloy is a compelling and viable choice for sodium fast reactor fuel cladding applications.

36 MATERIALS SCIENCE↗
DOE OSTI2012

A beginner's guide to the modern theory of polarization

The so-called Modern Theory of Polarization, which rigorously defines the spontaneous polarization of a periodic solid and provides a route for its computation in electronic structure codes through the Berry phase, is introduced in a simple qualitative discussion. - Graphical abstract: Cartoon of Wannier functions in a covalent solid shifting to contribute to the ferroelectric polarization.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Physical and hydraulic properties of modern sinter deposits: El Tatio, Atacama

We report sinters are siliceous, sedimentary deposits that form in geothermal areas. Formation occurs in two steps. Hot water circulates in the subsurface and dissolves silica from the host rock, usually rhyolites. Silica then precipitates after hot water is discharged and cools. Extensive sinter formations are linked to up-flow areas of fluids originating from high temperature (> 175 °C) deep reservoirs. Fluid geochemistry, microbial communities, and environmental conditions of deposition determine the texture of sinter and pore framework. Porosity strongly influences physical and hydraulic properties of rocks. To better understand the properties controlling the transport of fluids, and interpret geophysical observations in geothermal systems, here we studied 17 samples of modern geyserite sinter deposits (< 10 ka) from the active El Tatio geothermal field in northern Chile. We measured the physical properties (hydraulic, seismic, and electrical), and internal microstructure (using μX-Ray computed tomography). We find that the pore structure, and thus hydraulic and physical properties, is controlled by the distribution of microbial matter. Based on velocity-porosity relationships, permeability-porosity scaling, and image analysis of the 3D pore structure; we find that the physical and hydraulic properties of sinter more closely resemble those of vesicular volcanic rocks and other material formed by precipitation in geothermal settings (i.e., travertine) than clastic sedimentary rocks.

15 GEOTHERMAL ENERGY↗
DOE OSTI2012

Modern Nuclear Data Evaluation with the TALYS Code System

This paper presents a general overview of nuclear data evaluation and its applications as developed at NRG, Petten. Based on concepts such as robustness, reproducibility and automation, modern calculation tools are exploited to produce original nuclear data libraries that meet the current demands on quality and completeness. This requires a system which comprises differential measurements, theory development, nuclear model codes, resonance analysis, evaluation, ENDF formatting, data processing and integral validation in one integrated approach. Software, built around the TALYS code, will be presented in which all these essential nuclear data components are seamlessly integrated. Besides the quality of the basic data and its extensive format testing, a second goal lies in the diversity of processing for different type of users. The implications of this scheme are unprecedented. The most important are: 1. Complete ENDF-6 nuclear data files, in the form of the TENDL library, including covariance matrices, for many isotopes, particles, energies, reaction channels and derived quantities. All isotopic data files are mutually consistent and are supposed to rival those of the major world libraries. 2. More exact uncertainty propagation from basic nuclear physics to applied (reactor) calculations based on a Monte Carlo approach: 'Total' Monte Carlo (TMC), using random nuclear data libraries. 3. Automatic optimization in the form of systematic feedback from integral measurements back to the basic data. This method of work also opens a new way of approaching the analysis of nuclear applications, with consequences in both applied nuclear physics and safety of nuclear installations, and several examples are given here. This applied experience and feedback is integrated in a final step to improve the quality of the nuclear data, to change the users vision and finally to orchestrate their integration into simulation codes.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗