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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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11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

National Climate Database (NCDB)

The National Climate Database (NCDB) is a high resolution, bias-corrected climate dataset consisting of the three most widely used variables of solar radiation- global horizontal (GHI), direct normal (DNI), and diffuse horizontal irradiance (DHI)- as well as other meteorological data. The goal of the NCDB is to provide unbiased high temporal and spatial resolution climate data needed for renewable energy modeling. The NCDB is modeled using a statistical downscaling approach with Regional Climate Model (RCM)-based climate projections obtained from the North American Coordinated Regional Climate Downscaling Experiment (NA-CORDEX; linked below). Daily climate projections simulated by the Canadian Regional Climate Model 4 (CanRCM4) forced by the second-generation Canadian Earth System Model (CanESM2) for two Representative Concentration Pathways (RCP4.5 or moderate emissions scenario and RCP8.5 or highest baseline emission scenario) are selected as inputs to the statistical downscaling models. The National Solar Radiation Database (NSRDB) is used to build and calibrate statistical models.

Array↗
DOE OSTI2019

Patterns in the Use of Axillary Operations for Patients with Node-Positive Breast Cancer After Neoadjuvant Chemotherapy: A National Cancer Database (NCDB) Analysis

Background: The American College of Surgeons Oncology Group (ACOSOG) Z1071 and Sentinel Neoadjuvant (SENTINA) trials of sentinel node biopsy for node-positive breast cancer treated with neoadjuvant chemotherapy (NAC) demonstrated false-negative rates that varied on the basis of surgical technique. This study evaluated trends in axillary operations before and after publication of these trials. Methods: This study analyzed patients from National Cancer Database (NCDB) with clinical T0 through T4, N1 and N2, M0 breast cancer who received NAC from 1 January 2012 to 31 December 2015 and sentinel lymph node biopsy (SNB) or axillary lymph node dissection (ALND). The patients were divided into the following groups: SNB, ALND, and (SNB + ALND). Results: Of the 32,036 evaluable patients identified in this study. 5565 had SNB, 19,930 had ALND, and 6541 had SNB + ALND. Compared with the ALND group, the SNB group was younger, had more invasive ductal cancers, and had lower clinical T- and N-stage disease (p < 0.001). The patients in the SNB group had a higher rate of estrogen receptor-positive and triple-negative breast cancers, but a lower rate of human epidermal growth factor receptor 2 (HER2)-positive cancer (p < 0.001). The nodal pathologic complete response (PCR) rate, defined as no residual invasive cancer, was 66.5% in the SNB group and 33.1% in the ALND group. Since 2013, the rate of ALND has decreased from 88.7 to 77.1% in both community and academic institutions (p < 0.001). Conclusion: Since publication of the ACOSOG Z1071 and SENTINA trials, the national rates of ALND in node positive breast cancer treated with NAC have decreased despite reported false-negative SNB rates and lack of prospective outcome data regarding the oncologic safety of ALND omission.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2024

The National Climate Data Base (NCDB): A Bias-Corrected High-Resolution Climate Dataset

Assessing renewable energy resources under future climate scenarios has been highlighted in recent years to analyze and understand potential impacts of future change in renewable generation on the power sector. Solar energy is well-known as the most plentiful among various renewable resources and usually converted to electricity using photovoltaics (PV) technologies, and the global deployment of PV technology has increased rapidly in recent decades. In this study, we develop a statistical technique to downscale the future projection of solar irradiance for PV energy-related applications. A set of Regional Climate Model (RCM)-based projections obtained from the North American Coordinated Regional Climate Downscaling Experiment (NA-CORDEX) are used as inputs to statistical methods to generate high-resolution global horizontal irradiance (GHI) over the contiguous United States (CONUS). The main steps of the statistical downscaling method include (1) regridding RCM output (0.22 degree and daily resolutions) to handle the modeled-observed data sets on a common grid, (2) correcting bias of RCM GHI using satellite-derived observation, and (3) implementing temporal and spatial downscaling to generate GHI at 8-km and hourly resolution. Basically, complex physical processes and interactions between solar radiation and various atmospheric constituents lead solar irradiance to be highly variable and uncertain. Underrepresentation of clouds from the RCM parameterizations is the main source of error and uncertainty in modeling solar irradiance. Thus, we adapt and use the high-quality satellite-derived data from the National Solar Radiation Database (NSRDB) to analyze the bias and error of RCM GHI as well as estimate the statistical parameters for spatial and temporal downscaling. This presentation will summarize the comprehensive analysis conducted to produce and assess the results under two climate scenarios (RCP4.5 and RCP8.5). We will also present a detailed validation demonstrating the strengths of the proposed downscaling method and future extension of this research.

climate data↗
DOE OSTI2024

The National Climate Database (NCDB): An Unbiased 100-Year Dataset for PV Modeling

In this study, we develop a statistical technique to downscale the future projection of solar irradiance for photovoltaics (PV) energy-related applications. A set of Regional Climate Model (RCM)-based projections obtained from the North American Coordinated Regional Climate Downscaling Experiment (NA-CORDEX) are used as inputs to statistical methods to generate high-resolution global horizontal irradiance (GHI) over the contiguous United States (CONUS). The main steps of the statistical downscaling method include (1) regridding RCM output (0.22 degree and daily resolutions) to handle the modeled-observed data sets on a common grid, (2) correcting bias of RCM GHI using satellite-derived observation, and (3) implementing temporal and spatial downscaling to generate GHI at 8-km and hourly resolution. Basically, complex physical processes and interactions between solar radiation and various atmospheric constituents lead solar irradiance to be highly variable and uncertain. Underrepresentation of clouds from the RCM parameterizations is the main source of error and uncertainty in modeling solar irradiance. Thus, we adapt and use the high-quality satellite-derived data from the National Solar Radiation Database (NSRDB) to analyze the bias and error of RCM GHI as well as estimate the statistical parameters for spatial and temporal downscaling. This presentation will summarize the comprehensive analysis conducted to produce and assess the results under two climate scenarios (RCP4.5 and RCP8.5). We will also present a detailed validation demonstrating the strengths of the downscaling method, a summary of the 100-year dataset from 2001-2100, and future extension of this research.

bias correction↗
DOE OSTI2015

Management Trends and Outcomes for Stage I to II Mantle Cell Lymphoma Using the National Cancer Data Base: Ascertaining the Ideal Treatment Paradigm

Purpose: Mantle cell lymphoma (MCL) is a rare, albeit aggressive subset of non-Hodgkin lymphoma, resulting in varied treatment approaches. Given the paucity of data defining the optimal management for early-stage MCL, we conducted an analysis using the National Cancer Data Base (NCDB) to identify practice patterns and outcomes. Methods and Materials: The NCDB was queried for patients with stage I to II MCL diagnosed from 1998 to 2012 receiving chemotherapy (CT) or radiation therapy (RT), or both (CT+RT). Univariate and multivariable analyses for factors associated with treatment selection were completed using logistic regression. Propensity scores with inverse probability treatment weighting (IPTW) were calculated based on the conditional probability of receiving CT+RT. The log-rank test and Cox proportional hazards modeling with IPTW adjustment were conducted for the survival analyses. Results: In total, 2539 patients were identified. The key characteristics were as follows: 69% were male, 71% were aged ≥60 years, 28% had extranodal involvement, and 51% had stage I disease. Of the 2539 patients, 70% underwent CT, 11% underwent RT, and 19% underwent CT+RT. The use of CT+RT decreased from 23.1% to 14.1% in 1998 to 2002 and 2010 to 2012 (P<.001). CT+RT usage was lower for patients with the following characteristics: age ≥60 years, female sex, stage II disease, and the presence of B symptoms. With a median follow-up period of 42.8 months, the unadjusted 3-year overall survival estimates for patients receiving CT, RT, or CT+RT were 67.8%, 72.4%, and 79.8%, respectively (P<.001). After correcting for indication bias through IPTW-adjusted modeling, CT+RT reduced the risk of overall mortality compared with monotherapy (hazard ratio 0.65, P=.029). Conclusions: Although uncommon, patients with stage I-II MCL can have favorable outcomes. Despite a continued decline in the usage of consolidative RT, combined modality therapy improves survival in this cohort compared with monotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Postoperative Chemoradiation Therapy in High-Risk Cervical Cancer: Re-evaluating the Findings of Gynecologic Oncology Group Study 109 in a Large, Population-Based Cohort

Purpose: To review the National Cancer Database (NCDB) to evaluate postoperative high-risk cervical cancer patients for factors associated with a benefit from chemoradiation therapy (CRT) over external beam radiation therapy alone (EBRT). Methods and Materials: The National Cancer Database was queried for women with cervical cancer treated with hysterectomy and adjuvant EBRT from 2002 to 2012. Only patients with pathologic lymph node involvement (LN+), positive surgical margins, and/or parametrial invasion were included in our analysis (on the basis of Peter's criteria). Univariable and multivariable analyses (MVA) were performed, and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to investigate for factors associated with of CRT utilization and overall survival (OS). Results: A total of 3053 patients met inclusion criteria, and 2479 received adjuvant CRT (81%), whereas 574 (19%) received EBRT alone. Factors associated with increased CRT utilization on MVA included age <69 years, year of diagnosis ≥2008, non-adenocarcinoma histology, and LN+. Use of CRT improved OS among the entire cohort on MVA (HR 0.76, CI 0.601-0.962; P=.022). On MVA, CRT improved OS in patients with LN+ as their sole Peter's criteria (HR 0.58, CI 0.413-0.814; P=.002). Chemoradiation therapy did not improve OS in patients with only positive margins (P=.73), only parametrial invasion (P=.95), or any combination of these 2 factors without LN+ (P=.63). Conclusions: The use of adjuvant CRT after hysterectomy improves OS in patients with high-risk cervical cancer compared with EBRT alone, but this benefit seems to be restricted to patients with LN+. The benefits of adjuvant CRT over EBRT alone in patients with parametrial invasion and/or positive margins (without nodal involvement) are unknown.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Survival Outcomes of Whole-Pelvic Versus Prostate-Only Radiation Therapy for High-Risk Prostate Cancer Patients With Use of the National Cancer Data Base

Purpose/Objectives: The addition of whole pelvic (WP) compared with prostate-only (PO) radiation therapy (RT) for clinically node-negative prostate cancer remains controversial. The purpose of our study was to evaluate the survival benefit of adding WPRT versus PO-RT for high-risk, node-negative prostate cancer, using the National Cancer Data Base (NCDB). Methods and Materials: Patients with high-risk prostate cancer treated from 2004 to 2006, with available data for RT volume, coded as prostate and pelvis (WPRT) or prostate alone (PO-RT) were included. Multivariate analysis (MVA) and propensity-score matched analysis (PSM) were performed. Recursive partitioning analysis (RPA) based on overall survival (OS) using Gleason score (GS), T stage, and pretreatment prostate-specific antigen (PSA) was also conducted. Results: A total of 14,817 patients were included: 7606 (51.3%) received WPRT, and 7211 (48.7%) received PO-RT. The median follow-up time was 81 months (range, 2-122 months). Under MVA, the addition of WPRT for high-risk patients had no OS benefit compared with PO-RT (HR 1.05; P=.100). On subset analysis, patients receiving dose-escalated RT also did not benefit from WPRT (HR 1.01; P=.908). PSM confirmed no survival benefit with the addition of WPRT for high-risk patients (HR 1.05; P=.141). In addition, RPA was unable to demonstrate a survival benefit of WPRT for any subset. Other prognostic factors for inferior OS under MVA included older age (HR 1.25; P<.001), increasing comorbidity scores (HR 1.46; P<.001), higher T stage (HR 1.17; P<.001), PSA (HR 1.81; P<.001), and GS (HR 1.29; P<.001), and decreasing median county household income (HR 1.15; P=.011). Factors improving OS included the addition of androgen deprivation therapy (HR 0.92; P=.033), combination external beam RT plus brachytherapy boost (HR 0.71; P<.001), and treatment at an academic/research institution (HR 0.84; P=.002). Conclusion: In the largest reported analysis of WPRT for patients with high-risk prostate cancer treated in the dose-escalated era, the addition of WPRT demonstrated no survival advantage compared with PO-RT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Association Between Treatment at a High-Volume Facility and Improved Survival for Radiation-Treated Men With High-Risk Prostate Cancer

Purpose: Although the association between higher hospital volume and improved outcomes has been well-documented in surgery, there is little data about whether this effect exists for radiation-treated patients. We investigated whether treatment at a radiation facility that treats a high volume of prostate cancer patients is associated with improved survival for men with high-risk prostate cancer. Methods and Materials: We used the National Cancer Database (NCDB) to identity patients diagnosed with prostate cancer from 2004 to 2006. The radiation case volume (RCV) of each hospital was based on its number of radiation-treated prostate cancer patients. We used propensity-score based analysis to compare the overall survival (OS) of high-risk prostate cancer patients in high versus low RCV hospitals. Primary endpoint is overall survival. Covariates adjusted for were tumor characteristics, sociodemographic factors, radiation type, and use of androgen deprivation therapy (ADT). Results: A total of 19,565 radiation-treated high-risk patients were identified. Median follow-up was 81.0 months (range: 1-108 months). When RCV was coded as a continuous variable, each increment of 100 radiation-managed patients was associated with improved OS (adjusted hazard ratio [AHR]: 0.97; 95% confidence interval [CI]: 0.95-0.98; P<.0001) after adjusting for known confounders. For illustrative purposes, when RCV was dichotomized at the 80th percentile (43 patients/year), high RCV was associated with improved OS (7-year overall survival 76% vs 74%, log-rank test P=.0005; AHR: 0.91, 95% CI: 0.86-0.96, P=.0005). This association remained significant when RCV was dichotomized at 75th (37 patients/year), 90th (60 patients/year), and 95th (84 patients/year) percentiles but not the 50th (19 patients/year). Conclusions: Our results suggest that treatment at centers with higher prostate cancer radiation case volume is associated with improved OS for radiation-treated men with high-risk prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

The Role of Adjuvant Radiotherapy in the Treatment of Pleural Mesothelioma

Background: Pleural mesothelioma is a rare but aggressive form of cancer. Local recurrence represents the majority of treatment failures and overall survival (OS) outcomes remain dismal. Adding locoregional treatment with radiotherapy after surgical resection has been considered but its role remains uncertain. Objective: The purpose of this study was to evaluate the outcomes of adjuvant radiation therapy (RT) for patients with malignant pleural mesothelioma. Methods: The National Cancer Data Base (NCDB) was queried (2004–2013) for patients with malignant mesothelioma. Patients were divided into three groups: observation, surgery alone, and surgery followed by adjuvant RT. Statistics included Fisher’s exact or Chi square tests to analyze categorical proportions between groups, Kaplan–Meier analysis to evaluate OS, and Cox proportional hazards modeling to determine variables associated with OS. Propensity matching was performed to make comparisons between homogenous groups. Results: Overall, the surgery plus radiotherapy group had a higher median survival (21.4 months) compared with surgery alone (16.59 months) [p < 0.001]. RT was more likely to be delivered after extrapleural pneumonectomy than with lung-sparing surgical approaches. On multivariable analysis, receipt of surgery plus radiotherapy, chemotherapy administration, and higher socioeconomic status were associated with improved OS (p < 0.0001). After propensity matching, receipt of surgery plus radiotherapy and chemotherapy administration were still associated with improved OS (p < 0.05). Conclusions: In the treatment of malignant pleural mesothelioma, adjuvant radiotherapy after surgical intervention was associated with improved OS. This study is the largest study of adjuvant radiotherapy to date, and our findings highlight the need for additional prospective data.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Better Defining the Role of Total Neoadjuvant Radiation: Changing Paradigms in Locally Advanced Pancreatic Cancer

Background: This study was designed to better define the role of radiation (Neo-Rad) in addition to neoadjuvant multiagent chemotherapy (NAT) for the treatment of locally advanced pancreatic cancer. Methods: Retrospective cohort study using the NCDB. Individuals with AJCC clinical T3/T4 pancreatic carcinoma who underwent resection and multiagent chemotherapy were included. Kaplan–Meier, logistic-regression, and Cox proportional-hazard models were used for analysis. Results: A total of 2703 patients were included; 2039 had T3 and 664 had T4 tumors, and 1092 (40.4%) received Neo-Rad. Median follow-up was 22.5 months. During the study period, there was increased use of NAT and a decline in the use of Neo-Rad. Addition of Neo-Rad did not affect 30-day (2.51% vs. 3.24%, p = 0.272) or 90-day mortality (5.23% vs. 6.38%, p = 0.216). Neo-Rad was not associated with improved overall survival on univariable (25.95 vs. 24.7 months, p = 0.202), or multivariable analyses (hazard ratio [HR] 0.94; 95% confidence interval [CI] 0.85–1.05). Time from diagnosis to definitive surgery was increased by Neo-Rad (204 vs. 115 days, p < 0.001). Neo-Rad was associated with increased pathologic downstaging in T3 (32.8% vs. 14.4%) (odds ratio [OR] 2.90; 95% CI 2.30–3.66) and T4 tumors (88.9% vs. 77.8%) (OR 2.29; 95% CI 1.44–3.67); complete pathologic response (5.3% vs. 1.6%) (OR 2.89; 95% CI 1.73–4.83), and increased R0 resection rates (85.7% vs. 76.8%) (OR 1.79; 95% CI 1.44–2.23). Conclusions: The use of neoadjuvant therapy is increasing for the treatment of locally advanced pancreatic cancer. The addition of radiation to neoadjuvant chemotherapy is associated with improved antineoplastic effectiveness (downstaging, complete pathologic response), surgical resection (R0 rates), but has no effect on overall survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗