SEARCH · Engineering Papers

Results for “57”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31

All sources NASA NTRS DOE OSTI

DOE OSTI2013

Molecular analysis of the human SLC13A4 sulfate transporter gene promoter

Highlights: ► Basal promoter activity of SLC13A4 −57 to −192 nt upstream of transcription initiation site. ► Human SLC13A4 5′-flanking region has conserved motifs with other placental species. ► Putative NFY, SP1 and KLF7 motifs in SLC13A4 5′-flanking region enhance transcription. -- Abstract: The human solute linked carrier (SLC) 13A4 gene is primarily expressed in the placenta where it is proposed to mediate the transport of nutrient sulfate from mother to fetus. The molecular mechanisms involved in the regulation of SLC13A4 expression remain unknown. To investigate the regulation of SLC13A4 gene expression, we analysed the transcriptional activity of the human SLC13A4 5′-flanking region in the JEG-3 placental cell line using luciferase reporter assays. Basal transcriptional activity was identified in the region −57 to −192 nucleotides upstream of the SLC13A4 transcription initiation site. Mutational analysis of the minimal promoter region identified Nuclear factor Y (NFY), Specificity protein 1 (SP1) and Krüppel like factor 7 (KLF7) motifs which conferred positive transcriptional activity, as well as Zinc finger protein of the cerebellum 2 (ZIC2) and helix–loop–helix protein 1 (HEN1) motifs that repressed transcription. The conserved NFY, SP1, KLF7, ZIC2 and HEN1 motifs in the SLC13A4 promoter of placental species but not in non-placental species, suggests a potential role for these putative transcriptional factor binding motifs in the physiological control of SLC13A4 mRNA expression.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2026

Sub-melt nanosecond pulsed-laser induced densification and strain-field relaxation in single-crystal diamond

Dislocations and polishing-induced defect networks in synthetic diamond introduce local strain fields and broaden Raman features, limiting performance in optical, thermal, and electronic applications. Laser annealing is emerging as a promising approach to repair surface and near-surface defects in diamond without entering the melt regime, yet surface densification, defect-state modification, and associated structural changes have not been well quantified. In this work, we show that sub-melt nanosecond pulsed-laser annealing (PLA) induces near-surface densification and defect-mediated strain relaxation in single-crystal Chemical Vapor Deposition (CVD) diamond. Single- and two-pulse PLA were applied, and structural evolution was quantified using co-registered ISO 25,178 white-light interferometry, depth-resolved Raman spectroscopy, and cross-sectional STEM with geometric phase analysis (GPA). Across a 5 × 6 grid (n = 30), responsive regions exhibit large reductions in local slope (Sdq 45–65%), developed area (Sdr 60–90%), height spread (Sp, Sz 30–65%), void volume (Vv 57–60%), and roughness amplitude (Sa, Sq 48–57%), consistent with densification of ∼4–6.5 nm. Raman profiling shows narrowing of the diamond line and improved spectral uniformity to depths of ∼2–3 μm. Given that the Raman probing depth significantly exceeds the densified layer thickness, this response is interpreted as consistent with long-range strain-field redistribution originating from the near-surface region. STEM-GPA strain maps further support this interpretation, showing smoother strain fields, suppressed hotspots, and redistribution of localized strain concentrations following PLA. These results are consistent with defect-mediated strain relaxation and densification-driven modification of the near-surface energy state. The approach provides a scalable pathway for improving near-surface structural quality in diamond relevant to electronic, photonic, and quantum applications.

Areal surface metrology (ISO 25,178)↗

DOE OSTI2022

Biofilm formation and genomic features of Listeria monocytogenes strains isolated from meat and dairy industries located in Piedmont (Italy)

Listeria monocytogenes is considered a major challenge for the food industry as it can persist for long periods in food processing plants by forming biofilms. The aims of this study were: i) to assess the biofilm producing ability of 57 Listeria monocytogenes isolates previously subjected to whole-genome sequencing (WGS); ii) to compare the levels of biofilm formation with the presence or absence of biofilm associated genes. To determine the presence or absence of a known set of biofilm associated genes, a comparative genomic analysis was performed on each strain. Among Listeria monocytogenes isolates, 58 %, 38.5 % and 3.5 % exhibited weak, moderate or strong biofilm production, respectively. No difference in biofilm production was observed between food and environmental isolates. The percentage of Listeria monocytogenes strains isolated from meat products (57 %) classified as moderate or strong biofilm producers was higher than the percentage obtained for strains isolated from dairy products (28 %). Here, the presence of the Stress Survival Islet 1, the arsD stress gene and the truncated inlA protein was significantly associated with increased levels of biofilm. Combining biofilm phenotype with molecular and genotyping data may provide the opportunity to better understand the relationship between genes linked to biofilm formation in Listeria monocytogenes.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2011

Impact of Sequencing of Postmastectomy Radiotherapy and Breast Reconstruction on Timing and Rate of Complications and Patient Satisfaction

Purpose: There are few long-term studies of how the sequencing of postmastectomy radiotherapy (PMRT) and breast reconstruction (BR) affects the time to development of complications or patient satisfaction with BR. We therefore studied this issue. Methods and Materials: One hundred thirteen women who underwent BR at Beth Israel Deaconess Medical Center (Boston, MA) from 1999-2006 and also received PMRT were included. Complications requiring surgery were categorized as early (within 90 days of BR) or late. The median length of follow-up after BR was 46.5 months. Patients' general and esthetic satisfaction was assessed with a validated questionnaire. Results: Complications occurred among 32% of 57 women receiving PMRT before BR and 44% of 57 patients having BR before PMRT (p = 0.176). Early complications were more frequent in patients who had PMRT first (18%) than for those with BR first (11%) (p = 0.210); conversely, late complication rates in the two groups were 14% and 33%, respectively (p = 0.009). General satisfaction was comparable between the PMRT-first and BR-first groups (68% and 68%, respectively; p = 0.995); esthetic satisfaction rates were also similar (50% and 62%, respectively; p = 0.238). Conclusions: The sequencing of PMRT and BR did not have a substantial impact on the total risk of complications or patients' general and esthetic satisfaction. However, early complications tended to develop in patients having PMRT first, whereas patients having BR first had a higher risk of late complications. Additional study of the effects of sequencing of PMRT on particular types of reconstructions may help devise strategies for reducing these risks.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2011

Palliation by Low-Dose Local Radiation Therapy for Indolent Non-Hodgkin Lymphoma

Purpose: The purpose of this study was to assess the efficacy of a 2 Multiplication-Sign 2 Gy (total dose, 4 Gy) palliative radiation therapy (RT) regimen for treating patients with indolent non-Hodgkin lymphoma (NHL) in terms of response rate, response duration, and symptom relief. Methods and Materials: A retrospective chart review was conducted. Between 2003 and 2007, 54 patients with NHL were treated to 85 anatomical sites with a 2 Multiplication-Sign 2 Gy palliative regimen. Local response was assessed by clinical and/or radiographic data. Symptoms before and after treatment for each site treated were obtained from clinical notes in patient medical records. Median follow-up time was 1.3 years. Results: For the 54 patients, the median age at time of treatment was 71.1 years old, and 57% of them were male. Of the 85 disease sites treated, 56% of sites had indolent histology, 28% of sites were diagnosed with chronic lymphocytic leukemia (CLL), 13% of sites had aggressive histology, and 2% of sites were shown to have other histology. Overall response rate (ORR) was 81% (49% complete response [CR], 32% partial response [PR]). The 2-year rate for freedom from local progression was 50% (95% CI, 37%-61%). The ORR for follicular lymphoma, Mucosa associated lymphoid tissue (MALT), and marginal zone lymphoma (MZL) histology was 88%, compared with a 59% rate for CLL histology (p = 0.005). While the ORR was similar for tumors of different sizes, the CR rate for patients with tumors <5 cm tended to be higher than those with tumors >10 cm (CR rate of 57% vs. 27%, respectively; p = 0.06). For the 48 sites with clearly documented symptoms at pretreatment, 92% of sites improved after low-dose RT. Conclusions: Short-course low-dose palliative radiotherapy (2 Multiplication-Sign 2 Gy) is an effective treatment that results in high response rates for indolent non-Hodgkin lymphoma. This treatment regimen provides effective symptomatic relief for tumor bulk of all sizes.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2011

Reirradiation for Head-and-Neck Cancer: Delicate Balance Between Effectiveness and Toxicity

Purpose: To analyze the effectiveness and toxicity of reirradiation (re-RT) for head-and-neck cancer. Methods and Materials: A retrospective data analysis was performed of 58 patients who underwent re-RT with curative intent. Re-RT was given as definitive treatment in 53% of patients, whereas salvage surgery preceded reirradiation in 47%. The median cumulative RT dose was 119 Gy (range, 76-140). Concurrent chemotherapy was administered with re-RT (CRT) in 57% of patients. Event-free survival was defined as survival without recurrence and without serious toxicity ({>=}Grade 3). Results: Median follow-up was 57 months (range, 9-140). Locoregional (LR) control was 50% at 2 and 5 years. The 2-year and 5-year overall survival (OS) was 42% and 34%. The following factors were associated with improved OS: postoperative re-RT (vs. primary re-RT), treatment with RT only (vs. CRT) and interval >3 years between previous RT and re-RT. For patients treated with postoperative re-RT and definitive re-RT, the 5-year OS was 49% and 20%, respectively. Patients treated with CRT had a 5-year OS of 13%. Serious (late) toxicity {>=}Grade 3 was observed in 20 of 47 evaluable patients (43%). Three cases of treatment-related death were recorded. The 2- and 5-year serious toxicity-free interval was 59% and 55%, respectively. Associated with increased risk of serious toxicity were CRT and higher re-RT dose. The event-free survival rates at 2 and 5 years were 34% and 31%, respectively. Conclusions: Re-RT in head-and-neck cancer is associated with poor survival rates of 13-20% in patients with inoperable disease treated with primary (chemo-) re-RT. For this subgroup, however, no other curative options are available. Long-term disease control and survival can be achieved in patients who receive re-RT as an adjunct to surgical resection. The rates of serious toxicity after re-RT are high, with an incidence of approximately 45% at 5 years. Approximately 1 in 3 patients survived re-RT without recurrence and severe complications.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2012

Frequency and Clinical Significance of Previously Undetected Incidental Findings Detected on Computed Tomography Simulation Scans for Breast Cancer Patients

Purpose: To determine the frequency and clinical significance of previously undetected incidental findings found on computed tomography (CT) simulation images for breast cancer patients. Methods and Materials: All CT simulation images were first interpreted prospectively by radiation oncologists and then double-checked by diagnostic radiologists. The official reports of CT simulation images for 881 consecutive postoperative breast cancer patients from 2009 to 2010 were retrospectively reviewed. Potentially important incidental findings (PIIFs) were defined as any previously undetected benign or malignancy-related findings requiring further medical follow-up or investigation. For all patients in whom a PIIF was detected, we reviewed the clinical records to determine the clinical significance of the PIIF. If the findings from the additional studies prompted by a PIIF required a change in management, the PIIF was also recorded as a clinically important incidental finding (CIIF). Results: There were a total of 57 (6%) PIIFs. The 57 patients in whom a PIIF was detected were followed for a median of 17 months (range, 3-26). Six cases of CIIFs (0.7% of total) were detected. Of the six CIIFs, three (50%) cases had not been noted by the radiation oncologist until the diagnostic radiologist detected the finding. On multivariate analysis, previous CT examination was an independent predictor for PIIF (p = 0.04). Patients who had not previously received chest CT examinations within 1 year had a statistically significantly higher risk of PIIF than those who had received CT examinations within 6 months (odds ratio, 3.54; 95% confidence interval, 1.32-9.50; p = 0.01). Conclusions: The rate of incidental findings prompting a change in management was low. However, radiation oncologists appear to have some difficulty in detecting incidental findings that require a change in management. Considering cost, it may be reasonable that routine interpretations are given to those who have not received previous chest CT examinations within 1 year.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

Historical Trends in the Use of Radiation Therapy for Pediatric Cancers: 1973-2008

Purpose: This study was undertaken to assess historical trends in the use of radiation therapy (RT) for pediatric cancers over the past 4 decades. Methods: The National Cancer Institute's Surveillance, Epidemiology, and End Results database of the 9 original tumor registries (SEER-9) was queried to identify patients aged 0 to 19 years with acute lymphoblastic leukemia, acute myeloid leukemia, bone and joint cancer, cancer of the brain and nervous system, Hodgkin lymphoma, neuroblastoma, non-Hodgkin lymphoma, soft tissue cancer, Wilms tumor, or retinoblastoma from 1973 to 2008. Patients were grouped into 4-year time epochs. The number and percentage of patients who received RT as part of their initial treatment were calculated per epoch by each diagnosis group from 1973 to 2008. Results: RT use for acute lymphoblastic leukemia, non-Hodgkin lymphoma, and retinoblastoma declined sharply from 57%, 57%, and 30% in 1973 to 1976 to 11%, 15%, and 2%, respectively, in 2005 to 2008. Similarly, smaller declines in RT use were also seen in brain cancer (70%-39%), bone cancer (41%-21%), Wilms tumor (75%-53%), and neuroblastoma (60%-25%). RT use curves for Wilms tumor and neuroblastoma were nonlinear with nadirs in 1993 to 1996 at 39% and 19%, respectively. There were minimal changes in RT use for Hodgkin lymphoma, soft tissue cancer, or acute myeloid leukemia, roughly stable at 72%, 40%, and 11%, respectively. Almost all patients treated with RT were given external beam RT exclusively. However, from 1985 to 2008, treatments involving brachytherapy, radioisotopes, or combination therapy increased in frequency, comprising 1.8%, 4.6%, and 11.9% of RT treatments in brain cancer, soft tissue cancer, and retinoblastoma, respectively. Conclusions: The use of RT is declining over time in 7 of 10 pediatric cancer categories. A limitation of this study is a potential under-ascertainment of RT use in the SEER-9 database including the delayed use of RT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2013

Proton Beam Craniospinal Irradiation Reduces Acute Toxicity for Adults With Medulloblastoma

Purpose: Efficacy and acute toxicity of proton craniospinal irradiation (p-CSI) were compared with conventional photon CSI (x-CSI) for adults with medulloblastoma. Methods and Materials: Forty adult medulloblastoma patients treated with x-CSI (n=21) or p-CSI (n=19) at the University of Texas MD Anderson Cancer Center from 2003 to 2011 were retrospectively reviewed. Median CSI and total doses were 30.6 and 54 Gy, respectively. The median follow-up was 57 months (range 4-103) for x-CSI patients and 26 months (range 11-63) for p-CSI. Results: p-CSI patients lost less weight than x-CSI patients (1.2% vs 5.8%; P=.004), and less p-CSI patients had >5% weight loss compared with x-CSI (16% vs 64%; P=.004). p-CSI patients experienced less grade 2 nausea and vomiting compared with x-CSI (26% vs 71%; P=.004). Patients treated with x-CSI were more likely to have medical management of esophagitis than p-CSI patients (57% vs 5%, P<.001). p-CSI patients had a smaller reduction in peripheral white blood cells, hemoglobin, and platelets compared with x-CSI (white blood cells 46% vs 55%, P=.04; hemoglobin 88% vs 97%, P=.009; platelets 48% vs 65%, P=.05). Mean vertebral doses were significantly associated with reductions in blood counts. Conclusions: This report is the first analysis of clinical outcomes for adult medulloblastoma patients treated with p-CSI. Patients treated with p-CSI experienced less treatment-related morbidity including fewer acute gastrointestinal and hematologic toxicities.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

The Impact of Definitive Local Therapy for Lymph Node-Positive Prostate Cancer: A Population-Based Study

Purpose: To evaluate the survival outcomes for patients with lymph node-positive, nonmetastatic prostate cancer undergoing definitive local therapy (radical prostatectomy [RP], external beam radiation therapy [EBRT], or both) versus no local therapy (NLT) in the US population in the modern prostate specific antigen (PSA) era. Methods and Materials: The Surveillance, Epidemiology, and End Results database was queried for patients with T1-4N1M0 prostate cancer diagnosed from 1995 through 2005. To allow comparisons of equivalent datasets, patients were analyzed in separate clinical (cN+) and pathologically confirmed (pN+) lymph node-positive cohorts. Kaplan-Meier overall survival (OS) and prostate cancer-specific survival (PCSS) estimates were generated, with accompanying univariate log-rank and multivariate Cox proportional hazards comparisons. Results: A total of 796 cN+ and 2991 pN+ patients were evaluable. Among cN+ patients, 43% underwent EBRT and 57% had NLT. Outcomes for cN+ patients favored EBRT, with 10-year OS rates of 45% versus 29% (P<.001) and PCSS rates of 67% versus 53% (P<.001). Among pN+ patients, 78% underwent local therapy (RP 57%, EBRT 10%, or both 11%) and 22% had NLT. Outcomes for pN+ also favored local therapy, with 10-year OS rates of 65% versus 42% (P<.001) and PCSS rates of 78% versus 56% (P<.001). On multivariate analysis, local therapy in both the cN+ and pN+ cohorts remained independently associated with improved OS and PCSS (all P<.001). Local therapy was associated with favorable hazard ratios across subgroups, including patients aged ≥70 years and those with multiple positive lymph nodes. Among pN+ patients, no significant differences in survival were observed between RP versus EBRT and RP with or without adjuvant EBRT. Conclusions: In this large, population-based cohort, definitive local therapy was associated with significantly improved survival in patients with lymph node-positive prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

Prospective Evaluation of Dual-Energy Imaging in Patients Undergoing Image Guided Radiation Therapy for Lung Cancer: Initial Clinical Results

Purpose: A prospective feasibility study was conducted to investigate the utility of dual-energy (DE) imaging compared to conventional x-ray imaging for patients undergoing kV-based image guided radiation therapy (IGRT) for lung cancer. Methods and Materials: An institutional review board-approved feasibility study enrolled patients with lung cancer undergoing IGRT and was initiated in September 2011. During daily setup, 2 sequential respiration-gated x-ray images were obtained using an on-board imager. Imaging was composed of 1 standard x-ray image at 120 kVp (1 mAs) and a second image obtained at 60 kVp (4 mAs). Weighted logarithmic subtraction of the 2 images was performed offline to create a soft tissue-selective DE image. Conventional and DE images were evaluated by measuring relative contrast and contrast-to-noise ratios (CNR) and also by comparing spatial localization, using both approaches. Imaging dose was assessed using a calibrated ion chamber. Results: To date, 10 patients with stage IA to IIIA lung cancer were enrolled and 57 DE images were analyzed. DE subtraction resulted in complete suppression of overlying bone in all 57 DE images, with an average improvement in relative contrast of 4.7 ± 3.3 over that of 120 kVp x-ray images (P<.0002). The improvement in relative contrast with DE imaging was seen for both smaller (gross tumor volume [GTV] ≤5 cc) and larger tumors (GTV >5 cc), with average relative contrast improvement ratios of 3.4 ± 4.1 and 5.4 ± 3.6, respectively. Moreover, the GTV was reliably localized in 95% of the DE images versus 74% of the single energy (SE images, (P=.004). Mean skin dose per DE image set was 0.44 ± 0.03 mGy versus 0.43 ± 0.03 mGy, using conventional kV imaging parameters. Conclusions: Initial results of this feasibility study suggest that DE thoracic imaging may enhance tumor localization in lung cancer patients receiving kV-based IGRT without increasing imaging dose.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

Radiation Therapy to the Primary and Postinduction Chemotherapy MIBG-Avid Sites in High-Risk Neuroblastoma

Purpose: Although it is generally accepted that consolidation therapy for neuroblastoma includes irradiation of the primary site and any remaining metaiodobenzylguanidine (MIBG)-avid metastatic sites, limited information has been published regarding the efficacy of this approach. Methods and Materials: Thirty patients with high-risk neuroblastoma were treated at 1 radiation therapy (RT) department after receiving 5 cycles of induction chemotherapy and resection. All patients had at least a partial response after induction therapy, based upon international neuroblastoma response criteria. The primary sites were treated with 24 to 30 Gy whereas the MIBG-avid metastatic sites were treated with 24 Gy. RT was followed by high-dose chemotherapy with autologous stem cell rescue and 6 months of cis-retinoic acid. Results: The 5-year progression-free survival (PFS) and overall survival (OS) rates were 48% and 59%, respectively. The 5-year locoregional control at the primary site was 84%. There were no differences in locoregional control according to degree of primary surgical resection. The 5-year local control rate for metastatic sites was 74%. The 5-year PFS rates for patients with 0, 1, 2, and >3 postinduction MIBG sites were 66%, 57%, 20%, and 0% (P<.0001), respectively, whereas 5-year OS rates were 80%, 57%, 50%, and 0%, respectively (P<.0001). Conclusions: RT to the primary site and postinduction MIBG-positive metastatic sites was associated with 84% and 74% local control, respectively. The number of MIBG-avid sites present after induction chemotherapy and surgery was predictive of progression-free and overall survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

Incidence and Predictive Factors of Pain Flare After Spine Stereotactic Body Radiation Therapy: Secondary Analysis of Phase 1/2 Trials

Purpose/Objective(s): To perform a secondary analysis of institutional prospective spine stereotactic body radiation therapy (SBRT) trials to investigate posttreatment acute pain flare. Methods and Materials: Medical records for enrolled patients were reviewed. Study protocol included baseline and follow-up surveys with pain assessment by Brief Pain Inventory and documentation of pain medications. Patients were considered evaluable for pain flare if clinical note or follow-up survey was completed within 2 weeks of SBRT. Pain flare was defined as a clinical note indicating increased pain at the treated site or survey showing a 2-point increase in worst pain score, a 25% increase in analgesic intake, or the initiation of steroids. Binary logistic regression was used to determine predictive factors for pain flare occurrence. Results: Of the 210 enrolled patients, 195 (93%) were evaluable for pain flare, including 172 (88%) clinically, 135 (69%) by survey, and 112 (57%) by both methods. Of evaluable patients, 61 (31%) had undergone prior surgery, 57 (29%) had received prior radiation, and 34 (17%) took steroids during treatment, mostly for prior conditions. Pain flare was observed in 44 patients (23%). Median time to pain flare was 5 days (range, 0-20 days) after the start of treatment. On multivariate analysis, the only independent factor associated with pain flare was the number of treatment fractions (odds ratio = 0.66, P=.004). Age, sex, performance status, spine location, number of treated vertebrae, prior radiation, prior surgery, primary tumor histology, baseline pain score, and steroid use were not significant. Conclusions: Acute pain flare after spine SBRT is a relatively common event, for which patients should be counseled. Additional study is needed to determine whether prophylactic or symptomatic intervention is preferred.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2016

Impact of Using Audit Data to Improve the Evidence-Based Use of Single-Fraction Radiation Therapy for Bone Metastases in British Columbia

Purpose: To assess the impact of a population-based intervention to increase the consistency and use of single-fraction radiation therapy (SFRT) for bone metastases. Methods and Materials: In 2012, an audit of radiation therapy prescriptions for bone metastases in British Columbia identified significant interphysician and -center (26%-73%) variation in the use of SFRT. Anonymous physician-level and identifiable regional cancer center SFRT use data were presented to all radiation oncologists, together with published guidelines, meta-analyses, and recommendations from practice leaders. The use of SFRT for bone metastases from 2007 through 2011 was compared with use of SFRT in 2013, to assess the impact of the audit and educational intervention. Multilevel logistic regression was used to assess the relationship between the usage of SFRT and the timing of the radiation while controlling for potentially confounding variables. Physician and center were included as group effects to account for the clustered structure of the data. Results: A total of 16,898 courses of RT were delivered from 2007 through 2011, and 3200 courses were delivered in 2013. The rates of SFRT use in 2007, 2008, 2009, 2010, 2011, and 2013 were 50.5%, 50.9%, 48.3%, 48.5%, 48.0%, and 59.7%, respectively (P<.001). Use of SFRT increased in each of 5 regional centers: A: 26% to 32%; B: 36% to 56%; C: 39% to 57%; D: 49% to 56%; and E: 73% to 85.0%. Use of SFRT was more consistent; 3 of 5 centers used SFRT for 56% to 57% of bone metastases RT courses. The regression analysis showed strong evidence that the usage of SFRT increased after the 2012 intervention (odds ratio 2.27, 95% confidence interval 2.06-2.50, P<.0001). Conclusion: Assessed on a population basis, an audit-based intervention increased utilization of SFRT for bone metastases. The intervention reversed a trend to decreasing SFRT use, reduced costs, and improved patient convenience. This suggests that dissemination of programmatic quality indicators in oncology can lead to increased utilization of evidence-based practice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2017

Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses

The capacity of simulated high-level radioactive waste borosilicate glasses to incorporate sulfate has been studied as a function of glass composition. Combined Raman, 57 Fe Mössbauer and literature evidence supports the attribution of coordination numbers and oxidation states of constituent cations for the purposes of modelling, and results confirm the validity of correlating sulfate incorporation in multicomponent borosilicate radioactive waste glasses with different models. A strong compositional dependency is observed and this can be described by an inverse linear relationship between incorporated sulfate (mol% SO 4 2- ) and total cation field strength index of the glass, Σ(z/a 2 ), with a high goodness-of-fit (R 2 ≈ 0.950). Similar relationships are also obtained if theoretical optical basicity, Λ th (R 2 ≈ 0.930) or non-bridging oxygen per tetrahedron ratio, NBO/T (R 2 ≈ 0.919), are used. Results support the application of these models, and in particular Σ(z/a 2 ), as predictive tools to aid the development of new glass compositions with enhanced sulfate capacities.

36 MATERIALS SCIENCE↗

DOE OSTI2014

An ensemble Kalman filter for statistical estimation of physics constrained nonlinear regression models

A central issue in contemporary science is the development of nonlinear data driven statistical–dynamical models for time series of noisy partial observations from nature or a complex model. It has been established recently that ad-hoc quadratic multi-level regression models can have finite-time blow-up of statistical solutions and/or pathological behavior of their invariant measure. Recently, a new class of physics constrained nonlinear regression models were developed to ameliorate this pathological behavior. Here a new finite ensemble Kalman filtering algorithm is developed for estimating the state, the linear and nonlinear model coefficients, the model and the observation noise covariances from available partial noisy observations of the state. Several stringent tests and applications of the method are developed here. In the most complex application, the perfect model has 57 degrees of freedom involving a zonal (east–west) jet, two topographic Rossby waves, and 54 nonlinearly interacting Rossby waves; the perfect model has significant non-Gaussian statistics in the zonal jet with blocked and unblocked regimes and a non-Gaussian skewed distribution due to interaction with the other 56 modes. We only observe the zonal jet contaminated by noise and apply the ensemble filter algorithm for estimation. Numerically, we find that a three dimensional nonlinear stochastic model with one level of memory mimics the statistical effect of the other 56 modes on the zonal jet in an accurate fashion, including the skew non-Gaussian distribution and autocorrelation decay. On the other hand, a similar stochastic model with zero memory levels fails to capture the crucial non-Gaussian behavior of the zonal jet from the perfect 57-mode model.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2025

Theory meets experiment: Insights into structure and magnetic properties of Fe 1-x Ni x B alloy

Here, we studied the structural and magnetic properties of the solid solution Fe 1-x Ni x B through theoretical and experimental approaches. Powder X-ray diffraction, X-ray Pair Distribution Function analysis, and energy dispersive X-ray spectroscopy reveal that the Fe 1-x Ni x B solid solution crystallizes in the β-FeB structure type up to x = 0.6–0.7 and exhibits anisotropic unit cell volume contraction with increasing Ni concentration. Magnetic measurements showed a transition from ferromagnetism to paramagnetism around x = 0.7. For x = 0.5, the low (< 0.3 μ B ) magnetic moments suggest itinerant magnetism despite the relatively high Curie temperature (up to 225 K). Theoretical calculations indicated different types of magnetic orderings depending on the Fe/Ni atomic order, with the antiferromagnetic state being stable for ordered FeNiB 2 , whereas the ground state is ferromagnetic for the disordered alloy. Calculations also predicted the coexistence of low- and high-spin states in Fe atoms around the composition with x = 0.5, in line with the experimental evidence from 57 Fe Mössbauer spectroscopy. The two magnetically distinct Fe sites for x = 0.3, 0.4, and 0.5 observed by 57 Fe Mössbauer spectroscopy can also be interpreted as two magnetically different regions or clusters. The formation of these clusters could affect the critical behavior near a quantum magnetic transition based on a potential ferromagnetic quantum critical point identified computationally and experimentally near x = 0.64. This work highlights the complex interplay between structure and magnetism in Fe 1-x Ni x B alloys, suggesting areas for future research on quantum critical behavior.

Bhaskar, Gourab [Iowa State Univ., Ames, IA (Unite↗

DOE OSTI2015

The Ho–Ni–Ge system: Isothermal section and new rare-earth nickel germanides

The Ho–Ni–Ge system has been investigated at 1070 K and up to ~60 at% Ho by X-ray diffraction and microprobe analyses. Besides the eight known compounds, HoNi{sub 5}Ge{sub 3} (YNi{sub 5}Si{sub 3}-type), HoNi{sub 2}Ge{sub 2} (CeAl{sub 2}Ga{sub 2}-type), Ho{sub 2}NiGe{sub 6} (Ce{sub 2}CuGe{sub 6}-type), HoNiGe{sub 3} (SmNiGe{sub 3}-type), HoNi{sub 0.2÷0.6}Ge{sub 2} (CeNiSi{sub 2}-type), Ho{sub 37÷34}Ni{sub 6÷24}Ge{sub 57÷42} (AlB{sub 2}-type), HoNiGe (TiNiSi-type), Ho{sub 3}NiGe{sub 2} (La{sub 3}NiGe{sub 2}-type), the ternary system contains four new compounds: Ho{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type), HoNi{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Ho{sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) and ~Ho{sub 5}Ni{sub 2}Ge{sub 3} (unknown structure). Quasi-binary solid solutions were observed at 1070 K for Ho{sub 2}Ni{sub 17}, HoNi{sub 5}, HoNi{sub 7}, HoNi{sub 3}, HoNi{sub 2}, HoNi and Ho{sub 2}Ge{sub 3}, but no detectable solubility was found for the other binary compounds in the Ho–Ni–Ge system. Based on the magnetization measurements, the HoNi{sub 5}Ge{sub 3}, HoNi{sub 3}Ge{sub 2} and Ho{sub 3}Ni{sub 11}Ge{sub 4} (and isostructural (Tb, Dy){sub 3}Ni{sub 11}Ge{sub 4}) compounds have been found to show paramagnetic behavior down to 5 K, whereas Ho{sub 3}Ni{sub 2}Ge{sub 3} exhibits an antiferromagnetic transition at ~7 K. Additionally, the crystal structure of the new isostructural phases (Y, Yb)Ni{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Er{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type) and (Y, Tb, Dy, Er, Tm){sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) has been also investigated. - Graphical abstract: The Ho–Ni–Ge system has been investigated at 1070 K and up to ~60 at.% Ho by X-ray and microprobe analyses. Besides the eight known compounds, i.e. HoNi{sub 5}Ge{sub 3} (YNi{sub 5}Si{sub 3}-type), HoNi{sub 2}Ge{sub 2} (CeAl{sub 2}Ga{sub 2}-type), Ho{sub 2}NiGe{sub 6} (Ce{sub 2}CuGe{sub 6}-type), HoNiGe{sub 3} (SmNiGe{sub 3}-type), HoNi{sub 0.2÷0.6}Ge{sub 2} (CeNiSi{sub 2}-type), Ho{sub 37÷34}Ni{sub 6÷24}Ge{sub 57÷42} (AlB{sub 2}-type), HoNiGe (TiNiSi-type), Ho{sub 3}NiGe{sub 2} (La{sub 3}NiGe{sub 2}-type), the ternary system contains four new compounds: Ho{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type), HoNi{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Ho{sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) and ~Ho{sub 5}Ni{sub 2}Ge{sub 3} (unknown structure). Quasi-binary solid solutions were found to form at 1070 K from the binary Ho{sub 2}Ni{sub 17}, HoNi{sub 5}, HoNi{sub 7}, HoNi{sub 3}, HoNi{sub 2}, HoNi and Ho{sub 2}Ge{sub 3} compounds, while no detectable solubility was observed for the other binary compounds in the Ho–Ni–Ge system. Based on the magnetization measurements, the HoNi{sub 5}Ge{sub 3}, HoNi{sub 3}Ge{sub 2} and Ho{sub 3}Ni{sub 11}Ge{sub 4} (and isostructural (Tb, Dy){sub 3}Ni{sub 11}Ge{sub 4}) compounds have been found to show paramagnetic behavior down to 5 K, whereas Ho{sub 3}Ni{sub 2}Ge{sub 3} exhibits an antiferromagnetic transition at ~7 K. Additionally, the crystal structure of the new isostructural phases (Y, Yb)Ni{sub 3}Ge{sub 2} (ErNi{sub 3}Ge{sub 2}-type), Er{sub 3}Ni{sub 11}Ge{sub 4} (Sc{sub 3}Ni{sub 11}Ge{sub 4}-type) and (Y, Tb, Dy, Er, Tm){sub 3}Ni{sub 2}Ge{sub 3} (Hf{sub 3}Ni{sub 2}Si{sub 3}-type) has been also investigated. - Highlights: • Ho–Ni–Ge system has been investigated at 1070 K and up to ~60 at% Ho. • Eight known ternary holmium nickel germanides were confirmed in Ho–Ni–Ge. • Four new holmium nickel germanides were detected in Ho–Ni–Ge. • Eight new rare earth nickel germanides were detected in (Y, Tb, Dy, Er–Yb)–Ni–Ge. • HoNi{sub 5}Ge{sub 3}, HoNi{sub 3}Ge{sub 2},(Tb, Dy, Ho){sub 3}Ni{sub 11}Ge{sub 4} and Ho{sub 3}Ni{sub 2}Ge{sub 3} are paramagnet down to 5–7 K.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗