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DOE OSTI2018

Validation of Spawn Checks and Saltwater Age Assignments Based on Scales from Known Repeat-Spawning Steelhead

Abstract It is critical to resolve the effects of regeneration, false annuli, and resorption on interpretation of scale patterns. We used scales collected from known repeat-spawning steelhead Oncorhynchus mykiss from the Snake River to (1) determine the accuracy of spawn check identification and (2) investigate errors in assignment of saltwater ages before and after spawn checks. Scale readers (n = 4) accurately identified over 96% of known repeat spawners (n = 107) and did not identify spawn checks in known first-time spawners (n = 197). Scale resorption associated with the spawn check caused an obscured or lost saltwater annulus in 66% of samples, most frequently in fish that spent 2 years versus 1 year in saltwater. Presence or absence of an annulus after the spawn check was accurately assigned in 86% of samples (n = 100). The potential for scale resorption to affect interpretation of the life history of iteroparous anadromous salmonids is significant. We supply two examples of how circulus counts can provide guidance to scale readers, but this analysis should be customized to the growth characteristics of each stock of interest.

Copeland, Timothy↗

DOE OSTI2016

Preparation of Single-Layer MoS 2x Se 2(1-x) and Mo x W 1-x S 2 Nanosheets with High-Concentration Metallic 1T Phase

The high-yield and scalable production of single-layer ternary transition metal dichalcogenide nanosheets with ≈66% of metallic 1T phase, including MoS 2x Se 2(1-x) and Mo x W 1-x S 2 is here achieved via electrochemical Li-intercalation and the exfoliation method. Thin film MoS 2x Se 2(1-x) nanosheets drop-cast on a fluorine-doped tin oxide substrate are used as an efficient electrocatalyst on the counter electrode for the tri-iodide reduction in a dye-sensitized solar cell.

14 SOLAR ENERGY↗

DOE OSTI2022

Achieving High Stability and Performance in P2-Type Mn-Based Layered Oxides with Tetravalent Cations for Sodium-Ion Batteries

We report P2-type sodium-manganese-based layered cathodes, owing to their high capacity from both cationic and anionic redox, are a potential candidate for Na-ion batteries to replace Li-ion technology in certain applications. Still, the structure instability originates from irreversible oxygen redox at high voltage remains a challenge. Here, a high sustainability cobalt-free P2- Na 0.72 Mn 0.75 Li 0.24 X 0.01 O 2 (X= Ti/Si) cathode is developed. The outstanding capacity retention and voltage retention after 150 cycles are obtained in Na half-cells. Our finding shows Ti locates on the surface while Si diffuses to the bulk of the particles. Thus, Ti can act as protective layer that alleviate side reactions in carbonate-based electrolyte. Meanwhile, Si can regulate the local electronic structure and suppress oxygen redox activities. Notably, full-cells with hard carbon (≈300-335 Whkg -1 based on the cathode mass) deliver the capacity retention of 83% for P2- Na 0.72 Mn 0.75 Li 0.24 Si 0.01 O 2 and 66% for P2-Na 0.72 Mn 0.75 Li 0.24 Ti 0.01 O 2 after 500 cycles; this electrochemical stability is the best compared to other reported cathodes based on oxygen redox at present. The superior cycle performance also stems from the ability to inhibit microcracking and planar gliding within the particles. Altogether, this finding offers new composition towards developing high performance low-cost cathodes for Na-ion batteries and highlights the unique role of Ti/Si ions.

25 ENERGY STORAGE↗

DOE OSTI2024

Genome‐wide association studies on resistance to powdery mildew in cultivated emmer wheat

Abstract Powdery mildew, caused by the fungal pathogenBlumeria graminis(DC.) E. O. Speer f. sp.triticiEm. Marchal (Bgt), is a constant threat to global wheat (Triticum aestivumL.) production. Although ∼100 powdery mildew (Pm) resistance genes and alleles have been identified in wheat and its relatives, more is needed to minimizeBgt’s fast evolving virulence. In tetraploid wheat (Triticum turgidumL.), wild emmer wheat [T. turgidumssp.dicoccoides(Körn. ex Asch. & Graebn.) Thell.] accessions from Israel have contributed manyPmresistance genes. However, the diverse genetic reservoirs of cultivated emmer wheat [T. turgidumssp.dicoccum(Schrank ex Schübl.) Thell.] have not been fully exploited. In the present study, we evaluated a diverse panel of 174 cultivated emmer accessions for their reaction toBgtisolateOKS(14)‐B‐3‐1and found that 66% of accessions, particularly those of Ethiopian (30.5%) and Indian (6.3%) origins, exhibited high resistance. To determine the genetic basis ofBgtresistance in the panel, genome‐wide association studies were performed using 46,383 single nucleotide polymorphisms (SNPs) from genotype‐by‐sequencing and 4331 SNPs from the 9K SNP Infinium array. Twenty‐five significant SNP markers were identified to be associated withBgtresistance, of which 21 SNPs are likely novel loci, whereas four possibly represent emmer derivedPm4a,Pm5a,PmG16, andPm64. Most novel loci exhibited minor effects, whereas three novel loci on chromosome arms 2AS, 3BS, and 5AL had major effect on the phenotypic variance. This study demonstrates cultivated emmer as a rich source of powdery mildew resistance, and the resistant accessions and novel loci found herein can be utilized in wheat breeding programs to enhanceBgtresistance in wheat.

Genetics & Heredity↗

DOE OSTI2016

Prevalence, diagnosis and outcome of cleft lip with or without cleft palate in The Netherlands

ABSTRACT Objective To examine the accuracy and timing of diagnosis of fetal cleft lip with or without cleft palate ( CL ± P) in the years following the introduction of a national screening program, and to assess the completeness and accuracy of information in The Netherlands Perinatal Registry. Methods A list was obtained of cases with a prenatal or postnatal diagnosis of CL ± P from two fetal medicine units between 2008 and 2012. All cases of CL ± P were included irrespective of the presence or absence of additional anomalies. Cases were included if the estimated date of delivery was between 1 January 2008 and 31 December 2012. Results During the study period, 330 cases of CL ± P were identified, with a prevalence of 15 per 10 000 pregnancies. The number of cases that were detected before 24 weeks' gestation increased during the study period, while the rate of termination of pregnancy did not change significantly ( P = 0.511). CL ± P was isolated in 217 (66%) cases and karyotype was abnormal in 69 (21%) cases. In 5% of the cases in which CL ± P seemed to be isolated during the 18–23‐week anomaly scan, postnatal array comparative genomic hybridization (array‐ CGH ) revealed an abnormal karyotype and 50% of these cases had major additional anomalies. Examination of data from The Netherlands Perinatal Registry demonstrated that in 37% of cases CL ±P was not recorded in the pregnancy records. Conclusion CL ± P is increasingly being diagnosed prenatally, without a significant effect on the rate of pregnancy termination. Further improvement in the diagnostic accuracy may be achieved by advocating prenatal array‐ CGH to reduce the frequency of unexpected anomalies being diagnosed after birth. It is important that healthcare providers register accurately the presence or absence of anomalies in the birth records to ensure that, in the future, data from The Netherlands Perinatal Registry can be relied upon to monitor prevalence. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Fleurke‐Rozema, J. H.↗

DOE OSTI2017

Measurement of the ZZ production cross section in proton-proton collisions at $ \sqrt{s}=8 $ TeV using the ZZ → ℓ – ℓ + ℓ'ℓ' + and $ZZ\to {\ell}^{-}{\ell}^{+}\nu \overline{\nu} $ decay channels with the ATLAS detector

A measurement of the ZZ production cross section in the ℓ – ℓ + ℓ' – ℓ' + and ℓ – ℓ + νν¯channels (ℓ = e, μ) in proton-proton collisions at √s = 8TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb –1 collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ → ℓ – ℓ + ℓ' – ℓ' + and ZZ → ℓ – ℓ + νν¯ are measured in selected phase-space regions. The total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV is measured from the combination of the two channels to be 7.3±0.4(stat)±0.3(syst) –0.1 –0.2 (lumi)pb, which is consistent with the Standard Model prediction of 6.6 –0.6 +0.7 pb. The differential cross sections in bins of various kinematic variables are presented. The differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Search for coherent elastic neutrino-nucleus scattering at a nuclear reactor with CONNIE 2019 data

The Coherent Neutrino-Nucleus Interaction Experiment (CONNIE) is taking data at the Angra 2 nuclear reactor with the aim of detecting the coherent elastic scattering of reactor antineutrinos with silicon nuclei using charge-coupled devices (CCDs). In 2019 the experiment operated with a hardware binning applied to the readout stage, leading to lower levels of readout noise and improving the detection threshold down to 50 eV. The results of the analysis of 2019 data are reported here, corresponding to the detector array of 8 CCDs with a fiducial mass of 36.2 g and a total exposure of 2.2 kg-days. The difference between the reactor-on and reactor-off spectra shows no excess at low energies and yields upper limits at 95% confidence level for the neutrino interaction rates. In the lowest-energy range, 50 − 180 eV, the expected limit stands at 34 (39) times the standard model prediction, while the observed limit is 66 (75) times the standard model prediction with Sarkis (Chavarria) quenching factors.[graphic not available: see fulltext]

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2014

Measurement of the low-mass Drell-Yan differential cross section at √s = 7 TeV using the ATLAS detector

The differential cross section for the process Z/γ → ℓℓ (ℓ = e,μ) as a function of dilepton invariant mass is measured in pp collisions at √s = 7 TeV at the LHC using the ATLAS detector. The measurement is performed in the e and μ channels for invariant masses between 26 GeV and 66 GeV using an integrated luminosity of 1.6 fb -1 collected in 2011 and these measurements are combined. The analysis is extended to invariant masses as low as 12 GeV in the muon channel using 35 pb -1 of data collected in 2010. The cross sections are determined within fiducial acceptance regions and corrections to extrapolate the measurements to the full kinematic range are provided. Next-to-next-to-leading-order QCD predictions provide a significantly better description of the results than next-to-leading order QCD calculations, unless the latter are matched to a parton shower calculation.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2016

Search for Higgs boson off-shell production in proton-proton collisions at 7 and 8 TeV and derivation of constraints on its total decay width

A search is presented for the Higgs boson off-shell production in gluon fusion and vector boson fusion processes with the Higgs boson decaying into a WW pair and the W bosons decaying leptonically. The data observed in this analysis are used to constrain the Higgs boson total decay width. The analysis is based on the data collected by the CMS experiment at the LHC, corresponding to integrated luminosities of 4.9 inverse femtobarns at a centre-of-mass energy of 7 TeV and 19.4 inverse femtobarns at 8 TeV, respectively. An observed (expected) upper limit on the off-shell Higgs boson event yield normalised to the standard model prediction of 2.4 (6.2) is obtained at the 95% CL for the gluon fusion process and of 19.3 (34.4) for the vector boson fusion process. Observed and expected limits on the total width of 26 and 66 MeV are found, respectively, at the 95% confidence level (CL). These limits are combined with the previous result in the ZZ channel leading to observed and expected 95% CL upper limits on the width of 13 and 26 MeV, respectively.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2024

Measurement of the effective leptonic weak mixing angle

Using pp collision data at $\sqrt{s}$ = 13 TeV, recorded by the LHCb experiment between 2016 and 2018 and corresponding to an integrated luminosity of 5.4 fb −1 , the forward-backward asymmetry in the pp → Z/γ* → μ + μ − process is measured. The measurement is carried out in ten intervals of the difference between the muon pseudorapidities, within a fiducial region covering dimuon masses between 66 and 116 GeV, muon pseudorapidities between 2.0 and 4.5 and muon transverse momenta above 20 GeV. These forward-backward asymmetries are compared with predictions, at next-to-leading order in the strong and electroweak couplings. The measured effective leptonic weak mixing angle is ${\sin}^2{\theta}_{\textrm{eff}}^{\ell }=0.23147\pm 0.00044\pm 0.00005\pm 0.00023,$ where the first uncertainty is statistical, the second arises from systematic uncertainties associated with the asymmetry measurement, and the third arises from uncertainties in the fit model used to extract ${\sin}^2{\theta}_{\textrm{eff}}^{\ell }$ from the asymmetry measurement. This result is based on an arithmetic average of results using the CT18, MSHT20, and NNPDF31 parameterisations of the proton internal structure, and is consistent with previous measurements and with predictions from the global electroweak fit.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2019

Structure-activity relationships of novel dithiocarbamates containing α,β-unsaturated ketone fragment as potent anticancer agents

Based on the structure of novel lead compound 8 discovered by our group, systematic structural modification was carried out. A series of compound 8’s derivatives were synthesized and evaluated for their activities against human non-small cell lung cancer cell line H460. Among them, twelve compounds showed significant proliferation inhibition activities with IC{sub 50} values <1 μM and compound 12r was the most potent one. Further study on compound 12r revealed that it has significant inhibitory effect on the growth of eight kinds of cancer cell lines with IC{sub 50} values <1 μM. Especially for cell lines A375 and HCT116, the IC{sub 50} values of 12r achieved 63 nM and 66 nM, respectively. Meanwhile, our research results also revealed the following structure-activity relationships: (a) different substitutions on the benzene ring or heteroaromatic rings greatly effect on the activity; (b) the presence of α,β-unsaturated ketone fragment is favorable for the activity; (c) the receptor cavity binding with amine moiety might be a relatively small hydrophobic cavity. These results will be valuable for the further development of this novel kind of dithiocarbamates.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2021

The effects of electrically exploding gold bridgewires into inert and explosive powder beds

Abstract The particle velocity created in beds of both low-density inert sugar and explosive PETN as a function of distance from an exploding bridgewire was measured using optical velocimetry and a silvered PMMA window. As expected, more violent bridge-bursts (from a greater-stored-energy capacitive discharge unit) resulted in greater particle velocities and a better supported compaction wave in sugar. In all cases, ramp waves, not shocks, were observed in the inert sugar. Large window velocities were observed for very powerful bursts (up to 270 m/s), but bursts required for stochastic detonator operation conditions resulted in sugar/PMMA window velocities of only 8–10 m/s 0.85 mm from the bridge location. In contrast, after a distance of only 0.65 mm, a building shock wave was observed in PETN under both threshold and reliable firing conditions. Subsequently a hot-spot-driven shock-to-detonation (SDT) process was observed prior to full detonation. The measured buildup process accounts for $$\approx $$ ≈ 66% of the so-called excess transit time (ETT) between the observed and theoretical total function time for the particular exploding-bridge-wire (EBW) detonator studied. The remainder must occur in the powerful output pellet region. In contrast to a common understanding, the ETT is found to be a weak function of the discharge energy. Thus, the operation of the detonator after a bridge-burst energy-to-powder reaction transition process is found to be hot-spot-driven SDT in both the low- and high-density pellets.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

DOE OSTI2026

Rerouting reductant flux via protein tethering enhances biohydrogen production in Thermococcus kodakarensis

Microbes that generate copious amounts of hydrogen (H 2 ) via dark fermentation are a promising means to evolve and improve renewable biofuels. Many anaerobic hyperthermophilic archaea, such as the fast-growing, genetically tractable, heterotroph Thermococcus kodakarensis, produce generous quantities of H2 and provide an idealized platform to further optimize naturally high levels of biohydrogen reduction. Precise genetic manipulations and modifications to growth conditions have already resulted in substantial increases to H2 output but additional improvements are desired. An unexamined and potentially valuable route towards increased H 2 production is to tether select electron donor and acceptor proteins together to reroute and maximize the flow of electrons towards H 2 production. Such strategies have shown promise in Bacteria and Eukarya but have not yet been investigated in thermophilic Archaea. Here, we generate and evaluate twelve novel T. kodakarensis strains wherein a proteinaceous electron carrier (a ferredoxin, Fd) is physically tethered to the membrane-bound-hydrogenase (MBH), the sole H 2 producing enzyme, to direct electron flux towards biohydrogen generation. Growth assessments and H 2 output measurements demonstrate that strains encoding protein-fusions evolve up to ~ 40% more H2 per cell than the host strain. Eliminating H 2 consumption and alternative routes of electron sinks in concert with protein tethering further increased H2 output per cell for a maximum increase of ~ 66% over the host strain. Our results demonstrate that rerouting electron flux via protein tethering coupled with the elimination of reductant sinks is a promising means towards improved biohydrogen production in T. kodakarensis. KEY POINTS: Protein tethering between redox proteins can reroute electron flux in vivo. Enforced protein proximity results in ~ 40% increases in H2 production per cell. Protein-tethering provides a generalizable framework to redirect redox metabolism.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2019

MRI of pancreatic ductal adenocarcinoma: texture analysis of T2-weighted images for predicting long-term outcome

Purpose: To assess the association between T2-weighted imaging (T2WI) texture-analysis parameters and the pathological aggressiveness or long-term outcomes in pancreatic ductal adenocarcinoma (PDAC) patients. Methods: A total of 66 patients (mean age 65.3 ± 9.0 years) who underwent preoperative MRI followed by pancreatectomy for PDAC between 2013 and 2015 were included in this study. A radiologist performed a texture analysis twice on one axial image using commercial software. Differences in the tex parameters, according to pathological factors, were analyzed using a Student’s t test or an ANOVA with Tukey’s test. Univariate and multivariate Cox proportional hazards regression analyses were used to evaluate the association between tex parameters and recurrence-free survival (RFS) or overall survival (OS). Results: The mean follow-up time was 18.5 months, and there were 58 recurrences and 39 deaths. The mean of the positive pixel (MPP)-related factors was significantly lower in poorly differentiated tumors than in well-differentiated tumors as well as in cases with perineural invasion. The univariate Cox proportional hazards analysis showed a significant association between the tex parameters and RFS or OS. However, only tumor size was statistically significant after the multivariate analysis. Only tumor size and entropy with medium texture were significantly associated with OS after the multivariate analysis. Conclusions: Tumor size was a significant predictive factor for RFS and OS in PDAC patients. Although entropy with medium texture analysis was significantly associated with OS, there were also limitations in the texture analysis; thus, further study is necessary.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Predictive role of PI-RADSv2 and ADC parameters in differentiating Gleason pattern 3 + 4 and 4 + 3 prostate cancer

Purpose: To compare the predictive roles of qualitative (PI-RADSv2) and quantitative assessment (ADC metrics), in differentiating Gleason pattern (GP) 3 + 4 from the more aggressive GP 4 + 3 prostate cancer (PCa) using radical prostatectomy (RP) specimen as the reference standard. Methods: We retrospectively identified treatment-naïve peripheral (PZ) and transitional zone (TZ) Gleason Score 7 PCa patients who underwent multiparametric 3T prostate MRI (DWI with b value of 0,1400 and where unavailable, 0,500) and subsequent RP from 2011 to 2015. For each lesion identified on MRI, a PI-RADSv2 score was assigned by a radiologist blinded to pathology data. A PI-RADSv2 score ≤ 3 was defined as “low risk,” a PI-RADSv2 score ≥ 4 as “high risk” for clinically significant PCa. Mean tumor ADC (ADC{sub T}), ADC of adjacent normal tissue (ADC{sub N}), and ADC{sub ratio} (ADC{sub T}/ADC{sub N}) were calculated. Stepwise regression analysis using tumor location, ADC{sub T} and ADC{sub ratio}, b value, low vs. high PI-RADSv2 score was performed to differentiate GP 3 + 4 from 4 + 3. Results: 119 out of 645 cases initially identified met eligibility requirements. 76 lesions were GP 3 + 4, 43 were 4 + 3. ADC{sub ratio} was significantly different between the two GP groups (p = 0.001). PI-RADSv2 score (“low” vs. “high”) was not significantly different between the two GP groups (p = 0.17). Regression analysis selected ADC{sub T} (p = 0.03) and ADC{sub ratio} (p = 0.0007) as best predictors to differentiate GP 4 + 3 from 3 + 4. Estimated sensitivity, specificity, and accuracy of the predictive model in differentiating GP 4 + 3 from 3 + 4 were 37, 82, and 66%, respectively. Conclusions: ADC metrics could differentiate GP 3 + 4 from 4 + 3 PCa with high specificity and moderate accuracy while PI-RADSv2, did not differentiate between these patterns.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Percutaneous ureteral biopsy: safety and diagnostic yield

Purpose: To evaluate safety and diagnostic yield of percutaneous CT-guided biopsy of extrarenal upper urinary tract lesions. Materials and methods: Retrospective review of our institutional database of image-guided biopsies yielded 44 CT-guided percutaneous biopsies in 44 unique patients that targeted ureteral (30, 68%) or other non-renal upper urinary tract lesions (14, 32%) between January 1, 2000 and May 1, 2017. Indications, pre-biopsy imaging, biopsy technique, peri-procedural antithrombotic use, complications including bleeding defined by Society of Interventional Radiology criteria, pathology results, and subsequent imaging were reviewed up to 3 months after the procedure to evaluate safety and diagnostic yield. Results: Mean patient age was 66 (range 27–88) and 23/44 patients were male. The majority (34/44) of lesions were sampled with an 18-gauge biopsy device via a 17-gauge introducer needle, and the remaining 10/44 lesions were sampled with a 19/20 gauge system. The mean number of core samples obtained was 4 (range 2–10). No major complications occurred. Specifically, no patient developed a urine leak or urinary obstruction. Minor complications occurred in 3/44 (7%) biopsies, all retroperitoneal hemorrhages that did not require transfusion or other intervention. Biopsy was adequate for pathologic examination in 41 of 44 (93%) cases. Among patients undergoing surgical resection, biopsy diagnosis was concordant with surgical pathology in 9/10 (90%) cases and discordant in 1/10 (10%). Conclusion: CT-guided percutaneous biopsy of upper urinary tract lesions can be performed safely, with high diagnostic yield, and with a high rate of concordance on subsequent surgical pathology.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Double contrast-enhanced ultrasound improves the detection and localization of occult lesions in the pancreatic tail: a initial experience report

Purpose: The aim of this study is to review our initial experience of Double contrast-enhanced ultrasonography (DCEUS) in the preoperative detection of pancreatic tail occult tumors. Methods: Thirty-five patients were recruited to undergo DCEUS of the pancreas suspected by occult lesions of pancreatic with MRI or clinical evidence. The radiologists assessed the images (conventional US, DCEUS, and MRI) for enhancement phases, tumor presence, location, enhancement characteristics, and tumor conspicuity. The differences in the onset times of the phases between DCEUS and MRI were noted. Tumor conspicuity was graded on a four-point scale for conspicuity comparison among three imaging modalities. Results: Pancreatic tail tumors were missed on conventional transabdominal US in 11 of 35 patients. DCEUS revealed 12 lesions of 35 patients. Pancreatic tail tumors were identified on MRI in 10 of 35 patients. The sensitivity and specificity of DCEUS for depicting occult lesions of ≤ 2.2 cm were 92% and 95%, respectively. In contrast, the sensitivity and specificity of conventional US were 67% and 66%, respectively. The sensitivity and specificity of MRI were 91% and 88%, respectively. The conspicuity ratings of the three phases did not significantly differ between the DCEUS and MRI groups (P > 0.05). The DCEUS phases started much earlier than the corresponding MRI phases. Conclusion: DCEUS is a promising technique in the detection of occult pancreatic tail tumors and is possibly superior to dynamic enhanced MRI in the case of some peripheral lesions.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Diagnostic accuracy of MRI with extracellular vs. hepatobiliary contrast material for detection of residual hepatocellular carcinoma after locoregional treatment

Purpose: To compare the diagnostic accuracy of extracellular gadolinium-based contrast-enhanced MRI (Gd-MRI) and gadoxetic acid-enhanced MRI (EOB-MRI) for the assessment of hepatocellular carcinoma (HCC) response to locoregional therapy (LRT) using explant correlation as the reference standard. Methods: Forty-nine subjects with cirrhosis and HCC treated with LRT who underwent liver MRI using either Gd-MRI (n = 26) or EOB-MRI (n = 23) within 90 days of liver transplantation were included. Four radiologists reviewed the MR images blinded to histology to determine the size and percentage of viable residual HCC using a per-lesion explant reference standard. Sensitivities, specificities, accuracies, and agreement with histology for the detection residual HCC were calculated. Results: Gd-MRI had greater agreement with histology (ICC: 0.98 [0.95–0.99] vs. 0.80 [0.63–0.90]) and greater sensitivity for viable HCC (76% [13/17 50–93%] vs. 58% [7/12; 28–85%]) than EOB-MRI; specificities were similar (84% [16/19; 60–97%] vs. 85% [23/27; 66–96%]). Areas under ROC curves for detecting residual viable tumor were 0.80 (0.64–0.92) for Gd-MRI and 0.72 (0.55–0.85) for EOB-MRI. Gd-MRI had greater inter-rater agreement than EOB-MRI for determining the size of residual viable HCC (ICC: 0.96 [0.92–0.98] vs. 0.85 [0.72–0.92]). Conclusion: Gd-MRI may be more accurate and precise than EOB-MRI for the assessment of viable HCC following LRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗