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All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Highly Efficient Training, Refinement, and Validation of a Knowledge-based Planning Quality-Control System for Radiation Therapy Clinical Trials

Purpose: To demonstrate an efficient method for training and validation of a knowledge-based planning (KBP) system as a radiation therapy clinical trial plan quality-control system. Methods and Materials: We analyzed 86 patients with stage IB through IVA cervical cancer treated with intensity modulated radiation therapy at 2 institutions according to the standards of the INTERTECC (International Evaluation of Radiotherapy Technology Effectiveness in Cervical Cancer, National Clinical Trials Network identifier: 01554397) protocol. The protocol used a planning target volume and 2 primary organs at risk: pelvic bone marrow (PBM) and bowel. Secondary organs at risk were rectum and bladder. Initial unfiltered dose-volume histogram (DVH) estimation models were trained using all 86 plans. Refined training sets were created by removing sub-optimal plans from the unfiltered sample, and DVH estimation models… and DVH estimation models were constructed by identifying 30 of 86 plans emphasizing PBM sparing (comparing protocol-specified dosimetric cutpoints V{sub 10} (percentage volume of PBM receiving at least 10 Gy dose) and V{sub 20} (percentage volume of PBM receiving at least 20 Gy dose) with unfiltered predictions) and another 30 of 86 plans emphasizing bowel sparing (comparing V{sub 40} (absolute volume of bowel receiving at least 40 Gy dose) and V{sub 45} (absolute volume of bowel receiving at least 45 Gy dose), 9 in common with the PBM set). To obtain deliverable KBP plans, refined models must inform patient-specific optimization objectives and/or priorities (an auto-planning “routine”). Four candidate routines emphasizing different tradeoffs were composed, and a script was developed to automatically re-plan multiple patients with each routine. After selection of the routine that best met protocol objectives in the 51-patient training sample (KBP{sub FINAL}), protocol-specific DVH metrics and normal tissue complication probability were compared for original versus KBP{sub FINAL} plans across the 35-patient validation set. Paired t tests were used to test differences between planning sets. Results: KBP{sub FINAL} plans outperformed manual planning across the validation set in all protocol-specific DVH cutpoints. The mean normal tissue complication probability for gastrointestinal toxicity was lower for KBP{sub FINAL} versus validation-set plans (48.7% vs 53.8%, P<.001). Similarly, the estimated mean white blood cell count nadir was higher (2.77 vs 2.49 k/mL, P<.001) with KBP{sub FINAL} plans, indicating lowered probability of hematologic toxicity. Conclusions: This work demonstrates that a KBP system can be efficiently trained and refined for use in radiation therapy clinical trials with minimal effort. This patient-specific plan quality control resulted in improvements on protocol-specific dosimetric endpoints.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS080949 and Philips Healthcare research grant C32.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Pycheron: A Python-Based Seismic Waveform Data Quality Control Software Package

Supplementing an existing high-quality seismic monitoring network with openly available station data could improve coverage and decrease magnitudes of completeness; however, this can present challenges when varying levels of data quality exist. Without discerning the quality of openly available data, using it poses significant data management, analysis, and interpretation issues. Incorporating additional stations without properly identifying and mitigating data quality problems can degrade overall monitoring capability. If openly available stations are to be used routinely, a robust, automated data quality assessment for a wide range of quality control (QC) issues is essential. To meet this need, we developed Pycheron, a Python-based library for QC of seismic waveform data. Pycheron was initially based on the Incorporated Research Institutions for Seismology’s Modular Utility for STAtistical kNowledge Gathering but has been expanded to include more functionality. Pycheron can be implemented at the beginning of a data processing pipeline or can process stand-alone data sets. Its objectives are to (1) identify specific QC issues; (2) automatically assess data quality and instrumentation health; (3) serve as a basic service that all data processing builds on by alerting downstream processing algorithms to any quality degradation; and (4) improve our ability to process orders of magnitudes more data through performance optimizations. This article provides an overview of Pycheron, its features, basic workflow, and an example application using a synthetic QC data set.

58 GEOSCIENCES↗
DOE OSTI2014

TU-F-18A-01: Preliminary Results of a Prototype Quality Control Process for Spectral CT

Purpose: A prototype quality control (QC) phantom and analysis process has been designed specifically to monitor dual-energy CT and address the current lack of quantitative oversight of the spectral capabilities of these scanners. Methods: A prototype solid water phantom was designed with multiple material inserts, and to support both head and body protocols. Inserts included tissue equivalent and material rods (iodine, iron, calcium) at various concentrations. The oval body phantom, measuring 30cm×40cm×15cm, was scanned using four dual-energy protocols with CTDIvol ranges of 19.6–62mGy (0.516 pitch) and 10.3–32.5mGy (0.984 pitch), and rotation times ranging from 0.5-1sec. The circular head phantom, measuring 22cm in diameter by 15cm, was scanned using three dual-energy protocols with CTDIvol ranges of 67–132.6mGy (0.531 pitch) and 36.7–72.7mGy (0.969 pitch), and rotation times ranging from 0.5–0.9sec. All images were reconstructed at 50, 70, 110 and 140 keV, and using a water-iodine material basis pair. The images were evaluated for iodine quantification accuracy and stability of monoenergetic reconstructions. The phantom was scanned twice on ten GE 750HD CT scanners to evaluate inter-scanner agreement, as well as ten times on a single scanner over a oneweek period to evaluate intra-scanner repeatability. Results: Preliminary analysis revealed consistent (inter- and intra-scanner) iodine quantification accuracy within 10% was only achieved for protocols in the upper half of dose levels assessed when grouped by pitch. Although all scanners undergo rigorous daily single-energy QC, iodine quantification accuracy from one scanner unexpectedly deviated from the other nine substantially. In general, inter-scanner agreement and intra-scanner repeatability varied with dose, rotation time and reconstructed keV. Conclusion: Preliminary results indicate the need for a dual-energy QC process to ensure inter-scanner agreement and intra-scanner repeatability. In particular, iodine quantification accuracy within 10% may not be achievable using lower dose techniques. Future plans include longer term dual-energy CT QC data collection. In-kind financial support was provided by GE Healthcare.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

SU-C-BRD-01: A Statistical Modeling Method for Quality Control of Intensity- Modulated Radiation Therapy Planning

Purpose: To apply a statistical modeling approach, threshold modeling (TM), for quality control of intensity-modulated radiation therapy (IMRT) treatment plans. Methods: A quantitative measure, which was the weighted sum of violations of dose/dose-volume constraints, was first developed to represent the quality of each IMRT plan. Threshold modeling approach, which is is an extension of extreme value theory in statistics and is an effect way to model extreme values, was then applied to analyze the quality of the plans summarized by our quantitative measures. Our approach modeled the plans generated by planners as a series of independent and identically distributed random variables and described the behaviors of them if the plan quality was controlled below certain threshold. We tested our approach with five locally advanced head and neck cancer patients retrospectively. Two statistics were incorporated for numerical analysis: probability of quality improvement (PQI) of the plans and expected amount of improvement on the quantitative measure (EQI). Results: After clinical planners generated 15 plans for each patient, we applied our approach to obtain the PQI and EQI as if planners would generate additional 15 plans. For two of the patients, the PQI was significantly higher than the other three (0.17 and 0.18 comparing to 0.08, 0.01 and 0.01). The actual percentage of the additional 15 plans that outperformed the best of initial 15 plans was 20% and 27% comparing to 11%, 0% and 0%. EQI for the two potential patients were 34.5 and 32.9 and the rest of three patients were 9.9, 1.4 and 6.6. The actual improvements obtained were 28.3 and 20.5 comparing to 6.2, 0 and 0. Conclusion: TM is capable of reliably identifying the potential quality improvement of IMRT plans. It provides clinicians an effective tool to assess the trade-off between extra planning effort and achievable plan quality. This work was supported in part by NIH/NCI grant CA130814.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2026

Mu2e straw tube tracker gas flow quality control

Here, we present a tracker gas flow quality control method developed for the Mu2e straw tube tracker. Using time-dependent current measurements, we quantify the onset time of ionization gain induced by an 55 F source during gas exchange, which is correlated to the gas conductance in the straw. This allows for the identification of channels with inadequate flow. This approach is broadly applicable to other gaseous detectors that require high-channel-count screening.

Flow↗
DOE OSTI2014

WE-D-9A-06: Open Source Monitor Calibration and Quality Control Software for Enterprise Display Management

Purpose: Medical display monitor calibration and quality control present challenges to medical physicists. The purpose of this work is to demonstrate and share experiences with an open source package that allows for both initial monitor setup and routine performance evaluation. Methods: A software package, pacsDisplay, has been developed over the last decade to aid in the calibration of all monitors within the radiology group in our health system. The software is used to calibrate monitors to follow the DICOM Grayscale Standard Display Function (GSDF) via lookup tables installed on the workstation. Additional functionality facilitates periodic evaluations of both primary and secondary medical monitors to ensure satisfactory performance. This software is installed on all radiology workstations, and can also be run as a stand-alone tool from a USB disk. Recently, a database has been developed to store and centralize the monitor performance data and to provide long-term trends for compliance with internal standards and various accrediting organizations. Results: Implementation and utilization of pacsDisplay has resulted in improved monitor performance across the health system. Monitor testing is now performed at regular intervals and the software is being used across multiple imaging modalities. Monitor performance characteristics such as maximum and minimum luminance, ambient luminance and illuminance, color tracking, and GSDF conformity are loaded into a centralized database for system performance comparisons. Compliance reports for organizations such as MQSA, ACR, and TJC are generated automatically and stored in the same database. Conclusion: An open source software solution has simplified and improved the standardization of displays within our health system. This work serves as an example method for calibrating and testing monitors within an enterprise health system.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Quality control of mislocalized and orphan proteins

A healthy and functional proteome is essential to cell physiology. However, this is constantly being challenged as most steps of protein metabolism are error-prone and changes in the physico-chemical environment can affect protein structure and function, thereby disrupting proteome homeostasis. Among a variety of potential mistakes, proteins can be targeted to incorrect compartments or subunits of protein complexes may fail to assemble properly with their partners, resulting in the formation of mislocalized and orphan proteins, respectively. Quality control systems are in place to handle these aberrant proteins, and to minimize their detrimental impact on cellular functions. Here, we discuss recent findings on quality control mechanisms handling mislocalized and orphan proteins. We highlight common principles involved in their recognition and summarize how accumulation of these aberrant molecules is associated with aging and disease.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

FQC Dashboard: integrates FastQC results into a web-based, interactive, and extensible FASTQ quality control tool

Abstract Summary FQC is software that facilitates quality control of FASTQ files by carrying out a QC protocol using FastQC, parsing results, and aggregating quality metrics into an interactive dashboard designed to richly summarize individual sequencing runs. The dashboard groups samples in dropdowns for navigation among the data sets, utilizes human-readable configuration files to manipulate the pages and tabs, and is extensible with CSV data. Availability and implementation FQC is implemented in Python 3 and Javascript, and is maintained under an MIT license. Documentation and source code is available at: https://github.com/pnnl/fqc.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Quality control for community-based sea-ice model development

A new collaborative organization for sea-ice model development, the CICE Consortium, has devised quality control procedures to maintain the integrity of its numerical codes' physical representations, enabling broad participation from the scientific community in the Consortium's open software development environment. Using output from five coupled and uncoupled configurations of the Los Alamos Sea Ice Model, CICE, we formulate quality control methods that exploit common statistical properties of sea-ice thickness, and test for significant changes in model results in a computationally efficient manner. New additions and changes to CICE are graded into four categories, ranging from bit-for-bit amendments to significant, answer-changing upgrades. These modifications are assessed using criteria that account for the high level of autocorrelation in sea-ice time series, along with a quadratic skill metric that searches for hemispheric changes in model answers across an array of different CICE configurations. These metrics also provide objective guidance for assessing new physical representations and code functionality.

58 GEOSCIENCES↗
DOE OSTI2025

UR 2 : Ultra-rapid reactivity test for real-time, low-cost quality control of calcined clays

To reduce cement's carbon footprint, there is growing interest in commercial adoption of sustainable SCMs such as calcined clays. However, the existing ASTM standard (R 3 test, C1897) to test the reactivity of such clays takes up to 7 days and cannot be used for real-time quality control in an industrial setting. We address this issue by introducing a 5-min Ultra-Rapid Reactivity (UR 2 ) test. By dissolving 47 clay specimens in 4 M NaOH solutions at 90°C, we report that a dissolution index of 1.54Al + Si correlates strongly to the 7-day R 3 heat (R 2 = 0.92, RMSE = 94.1 J/g). This dissolution index also correlates to the 28-day compressive strength for 14 clay mixtures (R 2 = 0.94, RMSE = 1.7 MPa). This UR 2 test relies on colorimetry and can be conducted via off-the-shelf, low-cost cameras. Overall, our new UR 2 test opens a pathway for real-time, low-cost quality control of calcined clays.

36 MATERIALS SCIENCE↗
DOE OSTI2021

RACGAP1 modulates ECT2-Dependent mitochondrial quality control to drive breast cancer metastasis

Most cancer deaths are due to the colonization of tumor cells in distant organs. More evidence indicates that overexpression of RACGAP1 plays a critical role in cancer metastasis. However, the underlying mechanism still remains poorly understood. Here we found that RACGAP1 promoted breast cancer metastasis through regulating mitochondrial quality control. Overexpression of RACGAP1 in breast cancer cells led to the fragmentation of mitochondria, increased mitophagy intensity, mitochondrial turnover, and aerobic glycolysis ATP production. We showed that RACGAP1 promoted mitochondrial fission through recruiting ECT2 during anaphase and subsequently had activated ERK-DRP1 pathway. We further demonstrated the phosphorylation of RACGAP1 is essential for its ability of binding with ECT2 and its downstream effects. RACGAP1 overexpression also increased the expression of PGC-1a, a key mitochondrial biogenesis regulator, presumably by the increased mitophagy intensity induced by RACGAP1. PGC-1a increased the enrichment of DNMT1 in mitochondria, mitochondrial DNMT1 augmented mitochondrial DNA methylation and upregulated mitochondrial genome transcription. Our data indicated that RACGAP1 simultaneously facilitated mitophagy and mitochondrial biogenesis through regulating DRP1 phosphorylation and PGC-1a expression, eventually improved mitochondrial quality control in breast cancer cells. Our study provided a new angle in understanding the RACGAP1-overexpression related malignancy in breast cancer patients.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

Diameter Quality Control of Nb 3 Sn Wires for MQXF Cables in the USA

During this project, the 0.850 ± 0.003 mm Nb 3 Sn wires for the low-beta quadrupole magnets 'MQXFA' procured for the U.S. LHC Accelerator R&D Program (LARP) and the U.S. High Luminosity LHC Accelerator Upgrade Project (US HL-LHC AUP, or simply AUP) are received at Lawrence Berkeley National Laboratory (LBNL). There, the wires are respooled and then fabricated into Rutherford cables for winding coils. As part of the quality control program, AUP obtains from the wire manufacturer values of the maximum, average, minimum, and standard deviation of the two orthogonal axes, which are assessed prior to shipment approval. At LBNL, a dual-axis optical micrometer is used to measure the wire diameter of each spool every ~30 cm prior to cabling. This helps decide whether wire pieces with abnormal diameters should be distributed across the cable cross section, in order to improve cable parameter quality and mechanical stability consistency. This paper presents: 1) diameter data of LARP cables and of the first AUP cables made using wires acquired under LARP; 2) our deviation acceptance/rejection justification; and 3) the impact of wire diameter statistics on cable fabrication.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS1991

A multiple objective optimization approach to quality control

The use of product quality as the performance criteria for manufacturing system control is explored. The goal in manufacturing, for economic reasons, is to optimize product quality. The problem is that since quality is a rather nebulous product characteristic, there is seldom an analytic function that can be used as a measure. Therefore standard control approaches, such as optimal control, cannot readily be applied. A second problem with optimizing product quality is that it is typically measured along many dimensions: there are many apsects of quality which must be optimized simultaneously. Very often these different aspects are incommensurate and competing. The concept of optimality must now include accepting tradeoffs among the different quality characteristics. These problems are addressed using multiple objective optimization. It is shown that the quality control problem can be defined as a multiple objective optimization problem. A controller structure is defined using this as the basis. Then, an algorithm is presented which can be used by an operator to interactively find the best operating point. Essentially, the algorithm uses process data to provide the operator with two pieces of information: (1) if it is possible to simultaneously improve all quality criteria, then determine what changes to the process input or controller parameters should be made to do this; and (2) if it is not possible to improve all criteria, and the current operating point is not a desirable one, select a criteria in which a tradeoff should be made, and make input changes to improve all other criteria. The process is not operating at an optimal point in any sense if no tradeoff has to be made to move to a new operating point. This algorithm ensures that operating points are optimal in some sense and provides the operator with information about tradeoffs when seeking the best operating point. The multiobjective algorithm was implemented in two different injection molding scenarios: tuning of process controllers to meet specified performance objectives and tuning of process inputs to meet specified quality objectives. Five case studies are presented.

Seaman, Christopher Michael↗
NASA NTRS2022

QWIP: A Quantitative Metric for Quality Control of Aquatic Reflectance Spectral Shape using the Apparent Visible Wavelength

The colors of the ocean and inland waters span clear blue to turbid brown, and the corresponding spectral shapes of the waterleaving signal are diverse depending on the various types and concentrations of phytoplankton, sediment, detritus and colored dissolved organic matter. Here we present a simple metric developed from a global dataset spanning blue, green and brown water types to assess the quality of a measured or derived aquatic spectrum. The Quality Water Index Polynomial (QWIP) is founded on the Apparent Visible Wavelength (AVW), a one-dimensional geophysical metric of color that is inherently correlated to spectral shape calculated as a weighted harmonic mean across visible wavelengths. The QWIP represents a polynomial relationship between the hyperspectral AVW and a Normalized Difference Index (NDI) using red and green wavelengths. The QWIP score represents the difference between a spectrum’s AVW and NDI and the QWIP polynomial. The approach is tested extensively with both raw and quality controlled field data to identify spectra that fall outside the general trends observed in aquatic optics. For example, QWIP scores less than or greater than 0.2 would fail an initial screening and be subject to additional quality control. Common outliers tend to have spectral features related to: 1) incorrect removal of surface reflected skylight or 2) optically shallow water. The approach was applied to hyperspectral imagery from the Hyperspectral Imager for the Coastal Ocean (HICO), as well as to multispectral imagery from the Visual Infrared Imaging Radiometer Suite (VIIRS) using sensor-specific extrapolations to approximate AVW. This simple approach can be rapidly implemented in ocean color processing chains to provide a level of uncertainty about a measured or retrieved spectrum and flag questionable or unusual spectra for further analysis.

remote sensing reflectance↗