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PurposeThe ongoing lack of data standardization severely undermines the potential for automated learning from the vast amount of information routinely archived in electronic health records (EHRs), Radiation Oncology Information Systems (ROIS), treatment planning systems (TPSs), and other cancer care and outcomes databases. The effort sought to create a standardized ontology for clinical data, social determinants of health (SDOH), and other radiation oncology concepts and interrelationships.Methods and materialsThe American Association of Physicists in Medicine's (AAPM's) Big Data Science Committee (BDSC) was initiated July of 2019 to explore common ground from the stakeholders' collective experience of issues that typically compromise the formation of large inter- and intra- institutional databases from EHRs. The BDSC adopted an iterative, cyclical approach to engaging stakeholders beyond its membership to optimize the integration of diverse perspectives from the community.ResultsWe developed the Operational Ontology for Oncology (O3) which identified 42 key elements, 359 attributes, 144 value sets, and 155 relationships ranked in relative importance of clinical significance, likelihood of availability in EHRs, or the ability to modify routine clinical processes to permit aggregation. Recommendations are provided for best use and development of the O3 to four constituencies: device manufacturers, centers of clinical care, researchers, and professional societies.ConclusionsO3 is designed to extend and interoperate with existing global infrastructure and data science standards. The implementation of these recommendations will lower the barriers for aggregation of information that could be used creating large, representative, findable, accessible, interoperable and reusable (FAIR) datasets supporting the scientific objectives of grant programs. The construction of comprehensive "real world" datasets and application of advanced analytic techniques, including artificial

Measuring the temperature profile of a nanoscale sample using scanning thermal microscopy is challenging due to a scanning probe's non-uniform heating. In order to address this challenge, we have developed a calibration sample consisting of a 1-?m wide gold wire, which can be heated electrically by a small bias current. The Joule heating in the calibration sample wire is characterized using noise thermometry. A thermal probe was scanned in contact over the gold wire and measured temperature changes as small as 0.4?K, corresponding to 17?ppm changes in probe resistance. The non-uniformity of the probe's temperature profile during a typical scan necessitated the introduction of a temperature conversion factor, ?, which is defined as the ratio of the average temperature change of the probe with respect to the temperature change of the substrate. The conversion factor was calculated to be 0.035?±?0.007. Finite element analysis simulations indicate a strong correlation between thermal probe sensitivity and probe tip curvature, suggesting that the sensitivity of the thermal probe can be improved by increasing the probe tip curvature, though at the expense of the spatial resolution provided by sharper tips. Simulations also indicate that a bow-tie metallization design could yield an additional 5- to 7-fold increase in sensitivity., Microelectronics, Electrical Engineering, Mathematics and Computer Science

Measuring the temperature profile of a nanoscale sample using scanning thermal microscopy is challenging due to a scanning probe's non-uniform heating. In order to address this challenge, we have developed a calibration sample consisting of a 1-?m wide gold wire, which can be heated electrically by a small bias current. The Joule heating in the calibration sample wire is characterized using noise thermometry. A thermal probe was scanned in contact over the gold wire and measured temperature changes as small as 0.4?K, corresponding to 17?ppm changes in probe resistance. The non-uniformity of the probe's temperature profile during a typical scan necessitated the introduction of a temperature conversion factor, ?, which is defined as the ratio of the average temperature change of the probe with respect to the temperature change of the substrate. The conversion factor was calculated to be 0.035?±?0.007. Finite element analysis simulations indicate a strong correlation between thermal probe sensitivity and probe tip curvature, suggesting that the sensitivity of the thermal probe can be improved by increasing the probe tip curvature, though at the expense of the spatial resolution provided by sharper tips. Simulations also indicate that a bow-tie metallization design could yield an additional 5- to 7-fold increase in sensitivity., Microelectronics, Electrical Engineering, Mathematics and Computer Science

Metal microbolometers, used in scanning thermal microscopy, were microfabricated from <20?nm titanium thin films on SiO2/Si3N4/SiO2 cantilevers. These thin films are near the metal-insulator transition regime such that as the film thickness decreases—the resistance increases and the current-voltage characteristics cross over from sublinear to superlinear. In addition, the temperature coefficient of resistance transitions from positive to negative before it plateaus at a negative value. Thin titanium films exhibit negative temperature coefficient of resistance as high as ?0.0067/K which is higher than that of bulk titanium films., Electrical Engineering, Mathematics and Computer Science

Metal microbolometers, used in scanning thermal microscopy, were microfabricated from <20?nm titanium thin films on SiO2/Si3N4/SiO2 cantilevers. These thin films are near the metal-insulator transition regime such that as the film thickness decreases—the resistance increases and the current-voltage characteristics cross over from sublinear to superlinear. In addition, the temperature coefficient of resistance transitions from positive to negative before it plateaus at a negative value. Thin titanium films exhibit negative temperature coefficient of resistance as high as ?0.0067/K which is higher than that of bulk titanium films., Electrical Engineering, Mathematics and Computer Science