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NASA NTRS2018

A Laser-Induced Fluorescence Diagnostic for HERMeS and High-Power Electric Propulsion

NASA is continuing the development of a 12.5-kW Hall thruster system, which is baselined in a phased exploration concept to expand human presence to cis-lunar space and eventually to Mars. The development team is transitioning knowledge gained from the testing of the government-built Technology Development Unit (TDU) to the contractor-built Engineering Development Unit (EDU). A new laser-induced fluorescence diagnostic that is compatible with the testing of engineering hardware was developed to obtain data for thruster model validation in the lowest background pressure achievable. Prior to performing the test on the EDU, the team performed a functional checkout test of this new diagnostic using the TDU. In addition to providing a checkout of the diagnostic, this test provided data that can be correlated to electron mobility for comparison to the EDU at a later date. A number of technical challenges related to large test facilities and interfacing with engineering hardware were overcome while implementing the new laser diagnostic system. The initial data set was in good agreement with prior optical and non-optical diagnostics data collected on the TDU thrusters. This data set also revealed the spatial origin of high angle ions that have been of concern for spacecraft integration.

Huang, Wensheng↗

NASA NTRS2018

A Laser-Induced Fluorescence Diagnostic for HERMeS and High-Power Electric Propulsion

Huang, Wensheng↗

NASA NTRSDate not supplied

SPIKE-Dx : A Low-Power High-Throughput Fault Diagnostics Tool using Spiking Neural Networks for Constrained Systems

Diagnostic systems are important for many aerospace systems, which are severely limited in available power, like cubesats or UAVs. Therefore, traditional diagnostics systems cannot be used due to their substantial footprint and constraints. In this paper, we present our very low power diagnostic tool SPIKE-DX to monitor critical systems with constrained computational and energy resources. This is made possible through spiking neural networks (SNNs), which are executable within optimized simulation environments and further implemented on on cutting-edge neuromorphic hardware. Based upon FMEA (Failure Mode and Effect Analysis) framework, Diagnostic Bayesian Networks (DBNs) can be constructed that provide powerful means for diagnostic reasoning. In this paper, we describe such DBNs and a method to automatically translate the DBN into highly structured networks of spiking neurons for execution in SPIKE-DX.

Spiking Neural Networks↗

DOE OSTI2017

Application of quantitative methods for reliability testing of a nuclear power plant digital rod position indication diagnostic system - 391

Obsolescence, aging, reliability, and performance issues are driving nuclear facilities to replace conventional analog Instrumentation and Control (I and C) systems with digital technologies. In addition, the designs of the next generation of nuclear reactors, including Small Modular Reactors (SMRs), will incorporate digital I and C for most, if not all, of their safety and non-safety related functions. As part of an on-going research and development (R and D) effort under the auspices of the U.S. Department of Energy (DOE), Analysis and Measurement Services Corporation (AMS) is developing a platform to provide automated testing of digital I and C systems and create a standard method of evaluation for reliability assessments. This hands-on R and D effort has produced a Software Reliability Tester (SRT), which is a set of software and hardware tools designed to automate the testing of digital I and C systems to measure and quantify how well the systems perform under normal operating conditions and in the presence of faults. Furthermore, the SRT provides the foundation for a practical tool to automate verification and validation (V and V) activities and reduce the amount of testing time of digital I and C systems. When combined with its capabilities of integrating both reliability and fault tolerance quantification, the SRT can be used to ensure that digital I and C implementations are both safe and cost-effective for the nuclear industry. This paper describes the application of the SRT to perform V and V of a new Digital Rod Position Indication (DRPI) diagnostic system. The DRPI diagnostic system is a digital system that monitors the rod address and rod position data bus voltages of typical DRPI systems in nuclear power plants to detect and diagnose faults. For this application, the SRT was configured to exercise the inputs of the DRPI diagnostic system, and test cases were generated for common system faults such as address and data bit errors, bus voltage, and timing problems. These test cases were applied by the SRT hardware as voltage inputs to the DRPI diagnostic system and the outputs were compared to expected values generated by a model of the DRPI diagnostic system. Included in the paper is a description of the overall design of the SRT including the hardware and software architectures. Methodologies for automating test cases are also described. V and V using the SRT demonstrates the benefits of automated testing and qualification to provide a quantitative assessment of reliability and cost effective implementation of digital I and C in existing and next generation nuclear power plants. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2017

How to reduce Shutdown Dose Rates in ITER Diagnostics Equatorial Ports

The ITER vacuum vessel presents 54 access ports, arranged in three levels, where port plugs are inserted hosting different types of systems: test blanket modules, antennas, vacuum pumps, neutral beam injectors and diagnostics. At the equatorial level, nine out of the eighteen access ports present diagnostics port plugs, in which the diagnostics systems are deployed into three DSMs (Diagnostics Shield Modules). The DSMs, being a major constituent in volume of the port plugs, must help to fulfill the design target of Shutdown Dose Rates (SDDR) corresponding to 100 μSv.h{sup -1} after 10{sup 6} s of cooling time for planned in-situ maintenance operations in the port interspace. Additionally, the DSMs are largely responsible for the port plug drained weight limit of 45 T, which imposes limitations to the shielding technology. Up to now, all the proposed DSM designs combine differently stainless steel, water and/or B{sub 4}C as shielding to accommodate a maximum of 1.1 m{sup 3} of DSM bulk shield, contained into a L 1845 x W 518 x H 2011 mm stainless steel box weighting 5.8 T for each DSM. These proposals show insufficient shielding properties with respect to SDDR, while none of them satisfies currently the weight limit. However, during 2016, a new DSM concept has been developed, named 'modular DSM', with significant engineering advances and changes. The DSM length has been increased by 500 mm, up to 2345 mm. The SS box has been reduced to the minimum structure required, presenting the same weight while being larger and hosting a larger volume of bulk shielding inside. Thus, the volume of bulk shielding has been enlarged up to 1.5 m{sup 3} per DSM. The shielding technology is based on B{sub 4}C bricks deployed in SS trays that are attached to the vertical plates. This results in a bulk shielding made of 65% of B{sub 4}C, 10% SS and 25% void, with effective density of 2.4 g.cm{sup -3}. In summary, the modular DSM, without a weight increase, hosts extra 0.5 m3 of bulk shielding along an additional 500 mm of length, to be used with a light but highly neutron absorber, what allows fitting the weight limit of 45 T for the port plug once drained. From now, the non-modular DSMs will be referred as 'short DSMs'. The modular DSM's advantages with respect to the short DSM versions have shown that the DSMs design can be improved in generic approach, i.e. when the penetrations of the systems are not taken into consideration. A mention apart is required when port specific penetrations are considered. Provided that they will be an important radiation transmission path, their presence could significantly diminish the improvement. To clarify this issue, in this work we have carried out a nuclear analysis of the ITER equatorial port no. 11 integration considering the modular DSM. It is a first plasma port hosting the following 6 major diagnostics systems: Neutral Particle Analyzer (NPA), H-α monitor, Low Field Side (LFS) reflectometry, Visible - Ultraviolet divertor (VUV div), Visible - Ultraviolet core survey (VUV CS) and X-rays Crystal System (XRCS). For the baseline case, a SDDR matrix has been derived assigning responsibilities to the different EP no. 11 individual systems in terms of neutron flux transmission through them, and the related activation due to that neutron flux (activation of itself, but also of the rest of systems taken one by one). Different EP no. 11 configurations have been studied in addition to the baseline case. For example, the backfill of the port plug penetrations to protect all the empty space not required for systems sight. Another issue is the determination of the role of the Co impurity content minimization from 0.05 wt.% to 0.03 wt.% recently proposed. In this summary, only some results related to the baseline are given.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2020

Advanced diagnostics to evaluate heterogeneity in lithium-ion battery modules

Battery packs for electric and stationary applications experience varied operating conditions, including abuse—e.g., fast charging, overcharging, thermal, vibration, shock, etc.—throughout their lifetimes. Innovative diagnostic tools and algorithms that go beyond single cells and deal with modules and packs are essential for early detection of off-normal issues. High-resolution tools with known detection limits are key to developing appropriate mitigation strategies. With the advent of rapid impedance spectroscopy that can generate a broadband impedance spectrum in ~10 sec, the case for impedance-based diagnostics that can be readily aligned with other methods, such as incremental capacity or dQ.dV -1 , has become promising. This study used the aforementioned diagnostic methods to identify realistic in-vehicle battery abnormalities (e.g., localized self-discharge and non-uniform aging), in series (up to 10S) and parallel (4P) strings, using 16 Ah graphite/NMC cells. The impedance-based diagnostic is found to be sensitive to the string size and state. Depending on the type of abnormality, detection frequency varied. The dQ.dV -1 method showed the potential to detect long-term aging-related heterogeneity in modules. In general, both the impedance and dQ.dV -1 methods were able to detect series strings’ abnormalities, but struggled to find those issues within parallel modules.

25 ENERGY STORAGE↗

DOE OSTI2021

Compact, portable, laser induced fluorescence diagnostic for laboratory plasma sources

As diagnostic groups are increasingly called upon to participate in experimental campaigns at remote facilities, there is a need to develop portable versions of plasma diagnostic systems. One such diagnostic is laser induced fluorescence (LIF). Here, we describe a portable LIF apparatus that eliminates the need for an optical table, beam splitters, and an optical chopper. All of the light exiting the laser system is coupled through optical fibers to the experiment and housekeeping diagnostics. Here, the collected light is coupled through an optical fiber as well. A key feature is modulation of the tapered amplifier current instead of physical modulation of the laser output. Using this portable LIF system, measurements of ion temperature, ion flow, and relative metastable ion density are reported for two different remote experiments.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2023

Coherent microwave scattering for diagnostics of small plasma objects: A review

Measurements of parameters of small-size plasmas are very challenging because many traditional diagnostic approaches cannot be used. Constructive coherent microwave scattering (CMS) offers a convenient diagnostic solution for such small plasmas. This work reviews the development and applications of constructive coherent microwave scattering by the Electric Propulsion and Plasma Laboratory at Purdue University. It presents fundamentals of CMS with an emphasis on Thomson, collisional, and Rayleigh scattering in short, thin, unmagnetized plasma media. Additionally, we review examples of CMS application for diagnostics of temporally resolved plasma dynamics and electron decay, photoionization rates, electron momentum-transfer collision frequencies, and number densities of selective species in gaseous mixtures. These applications are relevant for various research fields including strong field and femtosecond filamentation physics, plasma-assisted ignition and combustion, and combustion and spacecraft electric propulsion diagnostics.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2024

Electrical design of the flexible imaging diffraction diagnostic for laser experiments (FIDDLE) at the National Ignition Facility (NIF)—Requirements, design, and performance

The Flexible Imaging Diffraction Diagnostic for Laser Experiments (FIDDLE) is a newly developed diagnostic for imaging time resolved diffraction in experiments at the National Ignition Facility (NIF). It builds on the successes of its predecessor, the Gated Diffraction Development Diagnostic (G3D). The FIDDLE was designed to support eight Daedalus version 2 sensors (six more hCMOS sensors than any other hCMOS-based diagnostic in NIF to date) and an integrated streak camera. We will review the electrical requirements, design, and performance of the electrical subsystems that were created to support this large number of cameras in the FIDDLE. The analysis of the data that the FIDDLE is intended to collect relies heavily on the accurate and well-understood timing of each sensor. We report camera-to-camera timing jitter of less than 100 ps rms and sensor integration times of 2.2 ns FWHM in 2-2 timing mode. Additionally, diffraction experiments on the NIF produce electric fields (EMI) on the order of 1 kV/m, which have been observed to negatively impact the performance of some electrical components of the FIDDLE. We report on the results of testing hCMOS camera electronics in a similar EMI environment generated in an offline lab. In addition, we also summarize the use of a novel approach to using a vector network analyzer as an EMI leak detector to understand and reduce the negative impacts of EMI on the FIDDLE.

47 OTHER INSTRUMENTATION↗

DOE OSTI2022

Progress in ITER ECE diagnostic design and integration

The ITER electron cyclotron emission (ECE) diagnostic system has primary roles in providing measurements of the core electron temperature profile and the electron temperature fluctuation associated with the neoclassical tearing modes. The ITER ECE system includes a radial and oblique line-of-sight. Four 43-meter long low-loss transmission lines (TLs) are designed to transmit millimeter wave power in the frequency range of 70–1000 GHz in both X- and O-mode polarization from the port plug to the ECE instrumentation room in the diagnostic building. The measurement instrumentation includes two Fourier transform spectrometer (FTS) systems and two radiometer systems. The Indian Domestic Agency (IN-DA) and United States Domestic Agency share the responsibility. The IN-DA scope excluding instrumentation and control has passed its preliminary design review and is progressing towards the final design review (FDR). In parallel, the diagnostic integration in different areas is ongoing. Furthermore, several captive components for the TLs have passed FDR and will be manufactured for installation in the tokamak building soon. A peer review meeting has been held on the prototype hot calibration source, and its integration and new thermal analysis in the diagnostic shield module are continuing. A prototype TL is being tested. A prototype polarizing Martin-Puplett type FTS, operating in the frequency range 70–1000 GHz, features an in-vacuo fast scanning mechanism and a cryo-cooled dual-channel THz detector system. Its performance has been assessed in detail against ITER requirements.

47 OTHER INSTRUMENTATION↗

DOE OSTI2024

The Physics behind Precipitation Onset Bias in CMIP6 Models: The Pseudo-Entrainment Diagnostic and Trade-Offs between Lapse Rate and Humidity

Conditional instability and the buoyancy of plumes drive moist convection but have a variety of representations in model convective schemes. Vertical thermodynamic structure information from Atmospheric Radiation Measurement (ARM) sites and reanalysis (ERA5), satellite-derived precipitation (TRMM3b42), and diagnostics relevant for plume buoyancy are used to assess climate models. Previous work has shown that CMIP6 models represent moist convective processes more accurately than their CMIP5 counterparts. However, certain biases in convective onset remain pervasive among generations of CMIP modeling efforts. Here we diagnose these biases in a cohort of nine CMIP6 models with sub-daily output, assessing conditional instability in profiles of equivalent potential temperature θ e and saturation equivalent potential temperature θ es in comparison to a plume model with different mixing assumptions. Most models capture qualitative aspects of the θ es vertical structure, including a substantial decrease with height in the lower free troposphere associated with the entrainment of subsaturated air. We define a “pseudo-entrainment” diagnostic that combines subsaturation and a θ es measure of conditional instability similar to what entrainment would produce under the small-buoyancy approximation. This captures the trade-off between larger θ es lapse rates (entrainment of dry air) and small subsaturation (permits positive buoyancy despite high entrainment). This pseudo-entrainment diagnostic is also a reasonable indicator of the critical value of integrated buoyancy for precipitation onset. Models with poor θ e /θ es structure (those using variants of the Tiedtke Scheme) or low entrainment runs of CAM5, and models with low subsaturation, such as NASA-GISS, lie outside the observational range in this diagnostic.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2017

Novel Infiltration Diagnostics based on Laser-line Scanning and Infrared Temperature Field Imaging

This project targets the building energy efficiency problems induced by building infiltration/leaks. The current infiltration inspection techniques often require extensive visual inspection and/or whole building pressure test. These current techniques cannot meet more than three of the below five criteria of ideal infiltration diagnostics: 1. location and extent diagnostics, 2. building-level application, 3. least surface preparation, 4. weather-proof, and 5. non-disruption to building occupants. These techniques are either too expensive or time consuming, and often lack accuracy and repeatability. They are hardly applicable to facades/facades section. The goal of the project was to develop a novel infiltration diagnostics technology based on laser line-scanning and simultaneous infrared temperature imaging. A laboratory scale experimental setup was designed to mimic a model house of well-defined pressure difference below or above the outside pressure. Algorithms and Matlab-based programs had been developed for recognition of the hole location in infrared images. Our experiment based on laser wavelengths of 450 and 1550 nm and laser beam diameters of 4-25 mm showed that the location of the holes could be identified using laser heating; the diagnostic approach however could not readily distinguish between infiltration and non-infiltration points. To significantly improve the scanning throughput and recognition accuracy, a second approach was explored, developed, and extensively tested. It incorporates a liquid spray on the surface to induce extra phase change cooling effect. In this spray method, we termed it as PECIT (Phase-change Enhanced Cooling Infrared Thermography), phase-change enhanced cooling was used, which significantly amplifies the effect of air flow (infiltration and exfiltration). This heat transfer method worked extremely well to identify infiltration and exfiltration locations with high accuracy and increased throughput. The PECIT technique was systematically developed and tested for through holes with diameters 1 mm to 2 mm, and diagonal lines of 0.5 mm width at different camera-wall distances of 46 cm to 200 cm, under different pressure differences from 5 Pa to 20 Pa, and under different wind conditions. The PECIT technique had either met or exceeded the goals proposed in the project. For exfiltration, we achieved 100% accuracy under a much lower pressure difference of 10 Pa (proposed one: 50 Pa with stretch goal of 15 Pa). For infiltration, we achieved >90% accuracy under a much lower pressure difference of 10 Pa (proposed one: 50 Pa with stretch goal of 15Pa). For exfiltration, we achieved 100% accuracy under a much lower pressure difference of 10 Pa. For infiltration, we achieved 100% accuracy under a much lower pressure difference of 10 Pa. The PECIT technique can reach a throughput of 120 m2/h, which is 4 times the proposed goal for the laser line-scanning and simultaneous infrared temperature imaging approach. For commercialization and market penetration, we had meetings with two companies for feedback collection and further improvement for practical use. Also, we have interacted with Office of Intellectual Property and Technology Transfer of Iowa State University for idea disclosure and patent application.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2023

Diagnostic Evaluation of the IS1081-Targeted Real-Time PCR for Detection of Mycobacterium bovis DNA in Bovine Milk Samples

The ability of Mycobacterium bovis (M. bovis) to survive in bovine milk has emerged as a serious public health concern. The first objective of this study was to evaluate the diagnostic utility of IS1081-targeted real-time PCR for the detection of M. bovis DNA in different fractions of bovine milk. In a model study, bovine milk samples were spiked with serially diluted M. bovis BCG to investigate the detection limit of M. bovis DNA in whole milk and milk fractions (cream, pellet, and pellet + cream combined) using IS1081 real-time PCR. The assay was then used to detect M. bovis DNA in whole milk and milk fractions from naturally infected animals. The results showed that the IS1081 real-time PCR was more sensitive when detecting M. bovis DNA in the cream layer alone and cream + pellet combined compared to whole milk or the pellet alone. While PCR-based diagnostic assays for the detection of M. bovis in milk samples provide a quicker diagnostic tool for bovine tuberculosis, safe processing, and handling of M. bovis-infected milk samples remain a challenge and pose a human health risk. PrimeStore Molecular Transport Medium (MTM) has been shown to rapidly inactivate infected specimens while preserving nucleic acid for subsequent Molecular analysis. Therefore, the secondary objective of this study was to evaluate the ability of MTM to inactivate M. bovis BCG in spiked milk samples as well as its ability to preserve BCG DNA for the PCR assay. The results showed that MTM can successfully inactivate BCG alone or in spiked milk samples while preserving DNA for the PCR assay. The CT values of M. bovis BCG alone and spiked milk samples aliquoted in MTM and without MTM were similar at various dilutions. Taken together, our results indicate that using DNA extracted from the milk cream fraction alone or combined milk cream and pellet improved the recovery rate of M. bovis DNA in bovine milk samples. MTM has the potential to provide a safe and rapid sample processing tool for M. bovis inactivation in milk samples and preserve DNA for molecular diagnostics.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2016

Considerations for a PDV diagnostic capability on the National Ignition Facility

Photonic Doppler Velocimetry (PDV) has become widely and routinely used in many high-velocity experimental applications due to its improved ease of use, cost, experimental flexibility, data return, and robustness compared to earlier velocimetric methods. However, these earlier methods have advantages in applications with requirements beyond PDV’s current capabilities. Various classes of experiments at the National Ignition Facility (NIF) that are characterized by extremely high velocity or acceleration, or diagnostic requirements for high precision in timing and/or velocity, have historically seen a VISAR (velocity interferometer system for any surface) diagnostic employed due to such advantages. VISAR, however, requires specific, and sometimes challenging, experimental features, including planar geometry and normal incidence, high-reflectivity surface treatment, and a relatively large and inflexible diagnostic footprint. Therefore, the potential for implementing a PDV diagnostic at NIF has been evaluated by researchers from National Security Technologies, LLC and Lawrence Livermore National Laboratory. We present the results of this study, weigh the relative merits of the two methodologies with consideration of experimental phenomena and requirements, and discuss possible implementations and future directions.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2019

Diagnostic performance of MRI- versus MDCT-categorized T3cd/T4 for identifying high-risk stage II or stage III colon cancers: a pilot study

Purpose: The aim of this study was to determine the diagnostic performance of magnetic resonance imaging (MRI)-categorized T3cd/T4 tumors for identifying high-risk stage II or stage III cancer in patients with curatively resectable colon cancer in comparison to that of multidetector computed tomography (MDCT). Materials and Methods: Thirty-eight patients with histopathologically indicated adenocarcinomas prospectively underwent MRI of the colon. Two radiologists independently and retrospectively assessed for T-category, including T3 substage (≤ T3ab vs. ≥ T3cd). The diagnostic accuracies and interreader agreements between assessments using each modality were compared using a pairwise comparison of receiver-operating characteristic curves and a weighted κ statistic, respectively. Results: Twenty-nine patients (76.3%) were histopathologically diagnosed with high-risk stage II or stage III colon cancer. The false-positive rate with MRI was lower than that with MDCT (0% vs. 7.9% for reader 1, 2.6% vs. 10.6% for reader 2). The diagnostic performance of MRI was better than that of MDCT across both readers (AUC: 0.707 vs. 0.506 [P = 0.032] for reader 1, 0.651 vs. 0.485 [P = 0.055] for reader 2). Moreover, MRI interreader agreement for the assessment of T3cd/T4 was significantly better than that of MDCT (κ = 0.821 vs. 0.391 [P = 0.017]). Conclusion: The diagnostic performance of MR imaging of the colon may be better than that of MDCT for identifying high-risk stage II or stage III cases. Particularly, colon MRI reduced the false-positive rate and improved the interreader agreement, although further studies with a larger sample size are required.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Image quality and diagnostic accuracy of complex-averaged high b value images in diffusion-weighted MRI of prostate cancer

Purpose: To evaluate the impact of complex-averaging on image quality (IQ) and diagnostic accuracy of acquired and calculated high b value (aHBV, cHBV) images in diffusion-weighted prostate MRI. Materials and methods: This retrospective study included 84 patients who underwent multiparametric prostate MRI at 3 Tesla without endorectal coil. DWIs were acquired at three different b values which included two lower b values (b = 50,900 s/mm{sup 2}) and one higher b value (aHBV at 2000 s/mm{sup 2}). The acquired data were postprocessed to generate two different types of trace-weighted images—using conventional magnitude-averaging and complex-averaging. Using lower b values (b = 50,900 s/mm{sup 2}) from both conventional and complex-averaged image sets, cHBV images (b = 2000 s/mm{sup 2}) and ADC maps were derived. All image sets were reviewed by two radiologists in different reading sessions to assess image quality and PIRADS. The diagnostic accuracy of different image sets for the detection of prostate lesions was performed by correlating PIRADS and Gleason scores. Results: Complex-averaging did not impact ADC values of the prostate lesions compared to magnitude-averaging (P = 0.08). Complex-averaging improved image quality of acquired high b value and calculated high b value images (P < 0.0001). Complex-averaging also improved the level of confidence (LOC) of the acquired high b value for both readers (P < 0.0001, P < 0.05), but only for reader A in calculated high b value (P < 0.0001). The image quality of calculated high b value images was not significantly different than acquired high b value images. The dataset combining complex-averaging and calculated high b value provided the highest diagnostic accuracy (but not statistically significant) for detection of the significant prostate lesion compared to the magnitude-averaged acquired high b value (79.55% vs. 72.73%; P = 0.317). The mean acquisition time for b = 2000 s/mm{sup 2} sequence (aHBV) was 6 min 30 s (± 1 min 16 s) out of a total of 28 min 31 s (± 4 min 26 s) for the entire mp-MRI protocol (approximately 25% of total scan time). Conclusion: Complex-averaging provides better image quality and level of confidence without significant impact on ADC values and diagnostic accuracy for detection of the significant prostate lesions . The calculated high b value images are also comparable to (and can substitute) the acquired high b value images which can help in reducing the imaging time.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Virtual Guidance of Percutaneous Transthoracic Needle Biopsy with C-Arm Cone-Beam CT: Diagnostic Accuracy, Risk Factors and Effective Radiation Dose

Purpose: C-arm cone-beam computed tomography-guided transthoracic lung core needle biopsy (CBCT-CNB) is a safe and accurate procedure for the evaluation of patients with pulmonary nodules. The purpose of our study was to evaluate the diagnostic performance, complication rates and effective radiation dose of CBCT-CNB with virtual guidance. Materials and Methods: We retrospectively collected data regarding 375 CBCT-CNBs performed with virtual guidance (XperGuide—Philips Healthcare, Best, The Netherlands) from January 2010 to June 2015 on 355 patients (mean age, 68.1 years ± 11.8; age range, 31–88 years). Patients were divided into groups and compared based on the diagnostic failure and lesion size (15 mm cutoff). Diagnostic performance, complication rate and effective radiation dose were investigated. Variables influencing diagnostic performance and complications were assessed using Student’s T test and Pearson’s χ{sup 2} test. Results: The sensitivity, specificity, positive and negative predictive value and accuracy for patients subjected to CNBs were 96.8%, 100%, 100%, 100% and 97.2%, respectively. Considering risk factors for pneumothorax, no significant differences were found regarding patient and lesion characteristics. Perilesional hemorrhage occurred more frequently in older patients (p = 0.046) and in smaller lesions (p = 0.001). Hemoptysis was significantly more frequent in patients with perilesional hemorrhage (p = 0.01). Mean effective radiation dose in CBCT-CNB was 7.12 ± 8.78 mSv. Conclusions: CBCT-CNB combined with virtual guidance is a reliable and accurate technique that allows exact localization of pulmonary lesions, effective preprocedural planning and real-time fluoroscopy altogether.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2018

Quantum dots in proteomic studies and medical diagnostics

Modern medical diagnostics requires the detection of minor amounts of target proteins at the background of numerous different biological components. With rare exception, these problems cannot be solved by purely physical research methods. In this case, the simplest and efficient approach is concerned with the principles of complementary affine interactions of biopolymers. In this case, high sensitivity of the analysis is achieved by the introduction of labels with certain physical properties in affinity bioreagents. This review is focused on the development of proteomic studies and medical diagnostics with the use of colloidal quantum dots (QDs) as labels in affinity bioreagents. This review is devoted to the description of in vitro proteomic approaches used in the studies and diagnostics, where the problem related to toxicity is not as crucial as in therapy and no restrictions on the types and composition of QDs are imposed. In this case, QDs are considered to be one of the key components of a bioanalytical system. The problems of proteomic medical diagnostics are discussed from the viewpoint of analytical chemistry with the account for the structure and properties of macromolecular analytes and appropriate bioreagents.

60 APPLIED LIFE SCIENCES↗