Diagnostic and prognostic values of 2-[18F]FDG PET/CT in resectable thymic epithelial tumour.

OBJECTIVES: We aimed to evaluate the diagnostic ability for the prediction of histologic grades and prognostic values on recurrence and death of pretreatment 2-[18F]FDG PET/CT in patients with resectable thymic epithelial tumours (TETs). METHODS: One hundred and fourteen patients with TETs who underwent pretreatment 2-[18F]FDG PET/CT between 2012 and 2018 were retrospectively evaluated. TETs were classified into three histologic subtypes: low-risk thymoma (LRT, WHO classification A/AB/B1), high-risk thymoma (HRT, B2/B3), and thymic carcinoma (TC). Area under the receiver operating characteristics curve (AUC) was used to assess the diagnostic performance of PET/CT variables (maximum standardised uptake value [SUVmax], metabolic tumour volume [MTV], total lesion glycolysis [TLG], maximum diameter). Cox proportional hazards models were built using PET/CT and clinical variables. RESULTS: The tumours included 52 LRT, 33 HRT, and 29 TC. SUVmax showed good diagnostic ability for differentiating HRT/TC from LRT (AUC 0.84, 95% confidence interval [CI] 0.76 - 0.92) and excellent ability for differentiating TC from LRT/HRT (AUC 0.94, 95% CI 0.90 - 0.98), with significantly higher values than MTV, TLG, and maximum diameter. With an optimal cut-off value of 6.4, the sensitivity, specificity, and accuracy for differentiating TC from LRT/HRT were 69%, 96%, and 89%, respectively. In the multivariable Cox proportional hazards analyses for freedom-from-recurrence, SUVmax was an independent prognostic factor (p < 0.001), whereas MTV and TLG were not. SUVmax was a significant predictor for overall survival in conjunction with clinical stage and resection margin. CONCLUSION: SUVmax showed excellent diagnostic performance for prediction of TC and significant prognostic value in terms of recurrence and survival. KEY POINTS: • Maximum standardised uptake value (SUVmax) shows excellent performance in the differentiation of thymic carcinoma from low- and high-risk thymoma. • SUVmax is an independent prognostic factor for freedom-from-recurrence in the multivariable Cox proportional hazard model and a significant predictor for overall survival. • 2-[18F]FDG PET/CT can provide a useful diagnostic and prognostic imaging biomarker in conjunction with histologic classification and stage and help choose appropriate management for thymic epithelial tumours.

SMART SKY EYE System for Preliminary Structural Safety Assessment of Buildings Using Unmanned Aerial Vehicles.

The development of unmanned aerial vehicles (UAVs) is expected to become one of the most commercialized research areas in the world over the next decade. Globally, unmanned aircraft have been increasingly used for safety surveillance in the construction industry and civil engineering fields. This paper presents an aerial image-based approach using UAVs to inspect cracks and deformations in buildings. A state-of-the-art safety evaluation method termed SMART SKY EYE (Smart building safety assessment system using UAV) is introduced; this system utilizes an unmanned airplane equipped with a thermal camera and programmed with various surveying efficiency improvement methods, such as thermography, machine-learning algorithms, and 3D point cloud modeling. Using this method, crack maps, crack depths, and the deformations of structures can be obtained. Error rates are compared between the proposed and conventional methods.

Assessment of Pharmacokinetics and Metabolism Profiles of SCH 58261 in Rats Using Liquid Chromatography-Mass Spectrometric Method.

5-Amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c) pyrimidine (SCH 58261) is one of the new chemical entities that has been developed as an adenosine A2A receptor antagonist. Although SCH 58261 has been reported to be beneficial, there is little information about SCH 58261 from a drug metabolism or pharmacokinetics perspective. This study describes the metabolism and pharmacokinetic properties of SCH 58261 in order to understand its behaviors in vivo. Rats were used as the in vivo model species. First, an LC-MS/MS method was developed for the determination of SCH 58261 in rat plasma. A GastroPlus™ simulation, in vitro microsomal metabolic stability, and bile duct-cannulated studies were also performed to understand its pharmacokinetic profile. The parameter sensitivity analysis of GastroPlus™ was used to examine the factors that influence exposure when the drug is orally administered. The factors are as follows: permeability, systemic clearance, renal clearance, and liver first-pass effect. In vitro microsomal metabolic stability indicates how much the drug is metabolized. The extrapolated hepatic clearance value of SCH 58261 was 39.97 mL/min/kg, indicating that the drug is greatly affected by hepatic metabolism. In vitro microsomal metabolite identification studies revealed that metabolites produce oxidized and ketone-formed metabolites via metabolic enzymes in the liver. The bile duct-cannulated rat study, after oral administration of SCH 58261, showed that a significant amount of the drug was excreted in feces. These results imply that the drug is not absorbed well in the body after oral administration. Taken together, SCH 58261 showed quite a low bioavailability when administered orally and this was likely due to significantly limited absorption, as well as high metabolism in vivo.

In Vitro, In Silico, and In Vivo Assessments of Pharmacokinetic Properties of ZM241385.

Parkinson's disease is one of the most common neurodegenerative diseases. Adenosine regulates the response to other neurotransmitters in the brain regions related to motor function. In the several subtypes of adenosine receptors, especially, adenosine 2A receptors (A2ARs) are involved in neurodegenerative conditions. ZM241385 is one of the selective non-xanthine A2AR antagonists with high affinity in the nanomolar range. This study describes the in vitro and in vivo pharmacokinetic properties of ZM241385 in rats. A liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qToF MS) method was developed for the determination of ZM241385 in rat plasma. In vivo IV administration studies showed that ZM241385 was rapidly eliminated in rats. However, the result of in vitro metabolic stability studies showed that ZM241385 had moderate clearance, suggesting that there is an extra clearance pathway in addition to hepatic clearance. In addition, in vivo PO administration studies demonstrated that ZM241385 had low exposure in rats. The results of semi-mass balance studies and the in silico PBPK modeling studies suggested that the low bioavailability of ZM241385 after oral administration in rats was due to the metabolism and by liver, kidney, and gut.

Discrepancies between coronary CT angiography and invasive coronary angiography with focus on culprit lesions which cause future cardiac events.

OBJECTIVES: To evaluate the clinical significance of discrepant lesions between coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) in a longitudinal study. METHODS: In 220 patients with suspected coronary artery disease (CAD) who underwent both 256-row CCTA and ICA, the obstructive CAD (≥ 50% stenosis) on CCTA was compared with that on ICA as the reference standard. We analysed the causes of the discrepancy between CCTA and ICA. During a 40-month follow-up period, major adverse cardiac events (MACE) were assessed. RESULTS: Discordance between CCTA and ICA was observed in 121 of the 3166 coronary artery segments (3.8%). Common causes were calcification (45.9%) and positive remodelling (PR) (29.6%) in 83 false positive lesions, and noise (40.0%) and motion artefact (37.8%) in 38 false negative lesions. MACE occurred in seven lesions among the discrepant lesions; six among the 29 PR lesions (20.7%) and one among the 53 calcified lesions (1.9%). With respect to the prediction power of MACE in an intermediate stenosis, the CCTA-related value including PR was higher than the ICA-related value. CONCLUSIONS: PR was a frequent cause of MACE among the false positive lesions on CCTA. Therefore, the presence of PR on CCTA may suggest clinical significance, although it can be missed by ICA. KEY POINTS: • Compared to ICA, PR in CCTA may be cause of false positive lesion. • CCTA-related value including PR shows higher prediction power of MACE than ICA-related value. • PR reflects atherosclerotic burden that can be related to cardiac events. • PR in CCTA should be observed carefully, even if it is false positive.

Phase II trial of epidermal growth factor ointment for patients with Erlotinib-related skin effects.

PURPOSE: The efficacy of erlotinib, the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has been demonstrated in patients with non-small cell lung cancer (NSCLC) and pancreatic cancer (PC). In the present study, we evaluated the effect of epidermal growth factor (EGF) ointment on erlotinib-related skin effects (ERSEs). METHODS: This was an open-label, non-comparative, multicenter, phase II trial. The patients included those diagnosed with NSCLC or PC who were treated with erlotinib. The effectiveness of the ointment was defined as follows: (1) grade 2, 3, or 4 ERSEs downgraded to ≤ grade 1 or (2) grade 3 or 4 ERSEs downgraded to grade 2 and persisted for at least 2 weeks. RESULTS: Fifty-two patients from seven institutes in Korea were enrolled with informed consent. The final assessment included 46 patients (30 males, 16 females). According to the definition of effectiveness, the EGF ointment was effective in 36 (69.2%) intention to treat patients. There were no statistically significant differences in the effectiveness of the EGF ointment by gender (p = 0.465), age (p = 0.547), tumor type (p = 0.085), erlotinib dosage (p = 0.117), and number of prior chemotherapy sessions (p = 0.547). The grading for the average National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE) rating of rash/acne and itching improved from 2.02 ± 0.83 to 1.13 ± 0.89 and 1.52 ± 0.84 to 0.67 ± 0.90, respectively (p < 0.001). The most common reason for discontinuing the study was progression of cancer (37%). CONCLUSIONS: Based on the results, the EGF ointment is effective for ERSEs, regardless of gender, age, type of tumor, and dosage of erlotinib. The EGF ointment evenly improved all kinds of symptoms of ERSEs. CLINICAL TRIAL REGISTRATION NO: ClinicalTrials.gov identifier: NCT01593995.

Performance management and policy evaluation of information and communication technology graduate program for developing countries.

As an educational aid, the Korean government has developed and funded a graduate-level global information telecommunications technology program (ITTP) for ICT officers in developing countries. Questions have arisen about whether the program can achieve its goals and obtain mutual benefits between Korea and participating nations. Using a total quality management (TQM) framework as a unique case analysis, we evaluated ITTP's resources and performance from 2006 to 2014. Our results show that ITTP has focused on the quantitative promotion of students and alums from various countries and their learning of Korea-centric ICT, policies, and culture. In particular, the Korean government's lax evaluation of ITTP performance has led to weak responsibility, ambiguous task identity, missed opportunities for self-improvement, and low participation among students and stakeholders. These findings highlight the need for graduate programs and their stakeholders to reinforce internal and external evaluations of the program's performance and provide feedback for reciprocal development.

An evaluation framework for low performers and human resource management planning: Application to a life insurance company in Korea.

This study comprehensively explores the factors that lead to low performers in an organization. A thorough literature review was conducted to construct an interview guide and obtain classification criteria for the factors that lead to low performers. Managers and low performers at multiple firms were interviewed individually to understand the various phenomena related to low performers in organizations. Based on the content of these interviews, 12 factors, classified into individual, leader, work, and organizational dimensions, were identified after three rounds of revisions by business administration experts. Next, a case study of Korea's S Life Insurance Company was conducted to examine the practical implications of the factors that contribute to creating low performers. In this case study, the analytic hierarchy process (AHP), involving eight departmental heads S Life Insurance Company's HR division, was utilized to identify the main factors that must be considered when evaluating low performers. While previous studies have examined low performers either at the individual, organizational, or institutional levels, this study presents a comprehensive and integrated evaluation framework of the factors that cause low performers. The proposed framework facilitates the identification and evaluation of low performers in various organizations and industries, and thus has practical implications in terms of establishing strategies to manage low performers more efficiently and improve organizational performance.

Circulating tumor cell microseparator based on lateral magnetophoresis and immunomagnetic nanobeads.

This paper presents a circulating tumor cell (CTC) microseparator for isolation of CTCs from human peripheral blood using immunomagnetic nanobeads with bound antiepithelial cell adhesive molecule (EpCAM) antibodies that specifically bind to epithelial cancer cells. The isolation is performed through lateral magnetophoresis, which is induced by high-gradient magnetic separation technology, involving a ferromagnetic wire array inlaid in the bottom substrate of a microchannel. Experimental results showed that the CTC microseparator isolates about 90% of spiked CTCs in human peripheral blood at a flow rate of up to 5 mL/h and purifies to approximately 97%. The overall isolation procedure was completed within 15 min for 200 µL of peripheral blood. CTCs from peripheral blood of patients with breast and lung cancers were isolated with the CTC microseparator, and the results were compared with those of healthy donors. Using a fluorescence-based viability assay, the viability of CTCs isolated from peripheral blood of patients with cancer was observed. In addition, the usefulness of the CTC microseparator for subsequent genetic assay was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR) amplification of cancer-specific genes using CTCs isolated from patients with cancer.

The efficacy and safety of carbon dioxide insufflation during colonoscopy with consecutive esophagogastroduodenoscopy in moderately sedated outpatients: a randomized, double-blind, controlled trial.

GOALS AND BACKGROUND: Colonoscopy with consecutive esophagogastroduodenoscopy (CCEGD) can be more convenient than performing each procedure individually. There has been no randomized controlled trial comparing carbon dioxide (CO2) versus air insufflations during CCEGD in sedated patients. CO2 insufflation instead of air during CCEGD may reduce abdominal pain and be more comfortable. We investigated the efficacy and safety of CO2 insufflation during CCEGD in moderately sedated outpatients. STUDY: This was a randomized, double-blind, controlled trial. A total of 96 outpatients were randomly assigned to the groups of CO2 or air insufflation. Postprocedure pain was assessed using a 0 to 10 visual analogue scale, and the proportion of pain-free patients was compared between the groups. Waist circumferences and end-tidal CO2 (ETCO2) were measured. RESULTS: Among 96 patients, cecal intubation failed in 2 patients, who were excluded from the analysis. Forty-eight patients in the CO2 and 46 patients in the air group completed the study. There was significant difference between the 2 groups regarding the proportion of pain-free patients 30 minutes after the procedures [air group, 35/46 (76.1%) vs. CO2 group, 44/48 (91.6%)] (P=0.03). However, there was no significant difference in the proportion at 6 and 24 hours after the procedures. The mean increase in waist circumference was greater with air than with CO2 (1.54 vs. 0.18 cm, P<0.001). The ETCO2 measured immediately after the procedures was slightly higher in the CO2 group than in the air group (38.6 vs. 37.2 mm Hg, P=0.02), but the values were within the normal range. No significant adverse events occurred. CONCLUSIONS: CO2 insufflation during CCEGD reduced postprocedural pain and distension compared with air. It was comfortable and safe to use in moderately sedated outpatients.

Low-volume morning-only polyethylene glycol with specially designed test meals versus standard-volume split-dose polyethylene glycol with standard diet for colonoscopy: a prospective, randomized trial.

BACKGROUND/AIMS: Split-dose polyethylene glycol (PEG) is a standard bowel preparation regimen for colonoscopy, but the large volume is burdensome to ingest and the night dose causes sleep disturbance. This study was performed to evaluate the efficacy and tolerability of a bowel preparation protocol using low-volume morning-only PEG with specially designed low-residue test meals (LV-PEG with TM) compared to a standard-volume split-dose PEG bowel preparation with a standard diet (SV-PEG with SD). METHODS: This was a single-center, prospective, randomized, investigator-blinded, noninferiority study. The primary end point was bowel preparation quality according to the Ottawa scale. Tolerability, compliance, adverse events, sleep quality and polyp/adenoma detection were also assessed. RESULTS: Among 197 patients analyzed (mean age 54.6 years, 51.3% men), 97 received LV-PEG with TM and 100 received SV-PEG with SD. The Ottawa score for the total colon was 3.76 ± 2.07 in the LV-PEG with TM group and 3.67 ± 1.57 in the SV-PEG with SD group (p = 0.723; difference 0.09, 95% confidence interval -0.60 to 0.42). The compliance was high (more than 95%) in both groups (p = 0.621). PEG was easier to ingest for patients in the LV-PEG with TM group compared to the SV-PEG with SD group [visual analogue scale (VAS) for difficulty: 4.64 ± 2.46 vs. 5.97 ± 2.42, respectively; p < 0.001]. Diet instructions were also easier to comply with for patients in the LV-PEG with TM group compared to the SV-PEG with SD group (VAS for difficulty: 3.11 ± 2.25 vs. 4.00 ± 2.39, respectively; p = 0.008). Patients in the LV-PEG with TM group had a lower incidence of abdominal bloating (p = 0.012) and better sleep quality (p < 0.001). There was no difference between the groups regarding polyp and adenoma detection. CONCLUSIONS: LV-PEG with TM and SV-PEG with SD have similar efficacy with regard to bowel preparation for colonoscopy. LV-PEG with TM provided easier PEG intake and diet compliance, less abdominal bloating and better sleep quality than SV-PEG with SD.

Deep learning proton beam range estimation model for quality assurance based on two-dimensional scintillated light distributions in simulations.

BACKGROUND: Many studies have utilized optical camera systems with volumetric scintillators for quality assurances (QA) to estimate the proton beam range. However, previous analytically driven range estimation methods have the difficulty to derive the dose distributions from the scintillation images with quenching and optical effects. PURPOSE: In this study, a deep learning method utilized to QA was used to predict the beam range and spread-out Bragg peak (SOBP) for two-dimensional (2D) map conversion from the scintillation light distribution (LD) into the dose distribution in a water phantom. METHODS: The 2D residual U-net modeling for deep learning was used to predict the 2D water dose map from a 2D scintillation LD map. Monte Carlo simulations for dataset preparation were performed with varying monoenergetic proton beam energies, field sizes, and beam axis shifts. The LD was reconstructed using photons backpropagated from the aperture as a virtual lens. The SOBP samples were constructed based on monoenergetic dose distributions. The training set, including the validation set, consisted of 8659 image pairs of LD and water dose maps. After training, dose map prediction was performed using a 300 image pair test set generated under random conditions. The pairs of simulated and predicted dose maps were analyzed by Bragg peak fitting and gamma index maps to evaluate the model prediction. RESULT: The estimated beam range and SOBP width resolutions were 0.02 and 0.19 mm respectively for varying beam conditions, and the beam range and SOBP width deviations from the reference simulation result were less than 0.1 and 0.8 mm respectively. The simulated and predicted distributions showed good agreement in the gamma analysis, except for rare cases with failed gamma indices in the proximal and field-marginal regions. CONCLUSION: The deep learning conversion method using scintillation LDs in an optical camera system with a scintillator is feasible for estimating proton beam range and SOBP width with high accuracy.

Optimal preparation-to-colonoscopy interval in split-dose PEG bowel preparation determines satisfactory bowel preparation quality: an observational prospective study.

BACKGROUND: Several factors influence bowel preparation quality. Recent studies have indicated that the time interval between bowel preparation and the start of colonoscopy is also important in determining bowel preparation quality. OBJECTIVE: To evaluate the influence of the preparation-to-colonoscopy (PC) interval (the interval of time between the last polyethylene glycol dose ingestion and the start of the colonoscopy) on bowel preparation quality in the split-dose method for colonoscopy. DESIGN: Prospective observational study. SETTING: University medical center. PATIENTS: A total of 366 consecutive outpatients undergoing colonoscopy. INTERVENTION: Split-dose bowel preparation and colonoscopy. MAIN OUTCOME MEASUREMENTS: The quality of bowel preparation was assessed by using the Ottawa Bowel Preparation Scale according to the PC interval, and other factors that might influence bowel preparation quality were analyzed. RESULTS: Colonoscopies with a PC interval of 3 to 5 hours had the best bowel preparation quality score in the whole, right, mid, and rectosigmoid colon according to the Ottawa Bowel Preparation Scale. In multivariate analysis, the PC interval (odds ratio [OR] 1.85; 95% CI, 1.18-2.86), the amount of PEG ingested (OR 4.34; 95% CI, 1.08-16.66), and compliance with diet instructions (OR 2.22l 95% CI, 1.33-3.70) were significant contributors to satisfactory bowel preparation. LIMITATIONS: Nonrandomized controlled, single-center trial. CONCLUSIONS: The optimal time interval between the last dose of the agent and the start of colonoscopy is one of the important factors to determine satisfactory bowel preparation quality in split-dose polyethylene glycol bowel preparation.

Structural Behavior of a Composite Curtain Wall Fabricated by the Fused Deposition Modeling 3D Printing Method.

In this era of the fourth industrial revolution, the integration of big data and 3D printing technology with the construction industry has maximized productivity. Currently, there is an active effort to research the optimal cladding structure through 3D printing technology to reduce production costs. This paper proposes a new type of 3D print curtain wall, using a high-strength ABS-M30 polymer panel, which is stronger than the standard acrylonitrile butadiene styrene (ABS) polymer, as an internally reinforced structure. This structure is fabricated via fused deposition modeling, a 3D printing method, to reduce the weight of the general cement panel. In addition, the shape of the polymer board was designed; three shapes were considered-O, W, and X types-which aided in further reducing the weight of the cladding. After comparing the center deformation of the structure through a lateral load test and finite element method analysis, the optimal model was selected. The measured data of the two methods at a design wind speed of 100% showed a difference of approximately 10%; however, at 150% of the design wind speed, the difference between the two sets of data increased to 27%.

Fire Resistance Performance of Steel-Polymer Prefabricated Composite Floors Using Standard Fire Tests.

In this study, the fire resistance performance of steel-polymer prefabricated composite floors, which have a sandwich-type structure, was assessed via standard fire tests and analyzed using finite element analysis. This form of analysis should consider two aspects, namely the thermal and structural fields, so as to simulate complicated material properties and large deformations. As previous studies have already conducted analysis in the thermal field, this study entailed only the structural analysis based on the temperature distributions obtained from the thermal analysis. The variables of the specimens were the thicknesses of the top and bottom steel plates and polymers. According to the analysis results, the top steel plate thickness had no impact on the stability ratings, a criterion for fire resistance performance, whereas the bottom steel plate showed a linear correlation with the stability rating. An equation for the stability rating of composite floors was proposed, and an equation for fire resistance performance was devised based on the insulation ratings, which were obtained from the thermal analysis results.

Bond Behavior of Concrete-Filled Steel Tube Mega Columns with Different Connectors.

Concrete-filled steel tubes (CFSTs) are widely used in construction. To achieve composite action and take full advantage of the two materials, strain continuity at the steel-concrete interface is essential. When the concrete core and steel tube are not loaded simultaneously in regions such as beam or brace connections to the steel tubes of a CFST column, the steel-concrete bond plays a crucial role in load transfer. This study uses a validated finite-element model to investigate the bond-slip behavior between the steel tube and concrete in square CFST mega columns through a push-out analysis of eleven 1.2- × 1.2-m mega columns. The bond-slip behavior of CFST mega columns with and without mechanical connectors, including shear studs, rib plates, and connecting plates, is studied. The finite-element results indicate that the mechanical connectors substantially increased the maximum bond stress. Among the analyzed CFST mega columns, those with closely spaced shear studs and rib plate connectors with circular holes exhibited the highest bond stress, followed by plate connectors and widely spaced shear stud connectors. In the case of shear stud connectors, the stud diameter and spacing influenced the bond behavior more than the stud length. As the stud spacing decreased, the failure mode shifted from studs shearing off to outward buckling of the steel tube.

Seismic Performance of F3D Free-Form Structures Using Small-Scale Shaking Table Tests.

In recent years, studies that can maximize irregularity have increased as technological constraints weaken owing to the development of construction technology and the increase in demand for free-form structures. Considering this, free-form structures have been constructed using various materials. Concrete is considered most suitable for realizing an atypical shape because it is highly economical and can be assembled in a free form. However, not many studies have evaluated the structural performance of free-form concrete structures using free-form formwork 3D printer (F3D) technology, a 3D printing technology. Free-form structures must be designed to secure structural stability under both dead and live loads, as well as natural hazards such as wind, snow, and earthquakes. Therefore, in this study, we tested a free-form structure constructed by F3D printing using small-scale models that satisfy the similitude law with shaking tables. Furthermore, a finite element analysis was conducted to validate the small-scale tests. Lastly, the seismic performance of free-form concrete structures was evaluated based on the test and analysis results.

Fully Automatic Quantitative Measurement of 18F-FDG PET/CT in Thymic Epithelial Tumors Using a Convolutional Neural Network.

OBJECTIVES: The aim of this study was to develop a deep learning (DL)-based segmentation algorithm for automatic measurement of metabolic parameters of 18F-FDG PET/CT in thymic epithelial tumors (TETs), comparable performance to manual volumes of interest. PATIENTS AND METHODS: A total of 186 consecutive patients with resectable TETs and preoperative 18F-FDG PET/CT were retrospectively enrolled (145 thymomas, 41 thymic carcinomas). A quasi-3D U-net architecture was trained to resemble ground-truth volumes of interest. Segmentation performance was assessed using the Dice similarity coefficient. Agreements between manual and DL-based automated extraction of SUVmax, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and 63 radiomics features were evaluated via concordance correlation coefficients (CCCs) and linear regression slopes. Diagnostic and prognostic values were compared in terms of area under the receiver operating characteristics curve (AUC) for thymic carcinoma and hazards ratios (HRs) for freedom from recurrence. RESULTS: The mean Dice similarity coefficient was 0.83 ± 0.34. Automatically measured SUVmax (slope, 0.97; CCC, 0.92), MTV (slope, 0.94; CCC, 0.96), and TLG (slope, 0.96; CCC, 0.96) were in good agreement with manual measurements. The mean CCC and slopes were 0.88 ± 0.06 and 0.89 ± 0.05, respectively, for the radiomics parameters. Automatically measured SUVmax, MTV, and TLG showed good diagnostic accuracy for thymic carcinoma (AUCs: SUVmax, 0.95; MTV, 0.85; TLG, 0.87) and significant prognostic value (HRs: SUVmax, 1.31 [95% confidence interval, 1.16-1.48]; MTV, 2.11 [1.09-4.06]; TLG, 1.90 [1.12-3.23]). No significant differences in the AUCs or HRs were found between automatic and manual measurements for any of the metabolic parameters. CONCLUSIONS: Our DL-based model provides comparable segmentation performance and metabolic parameter values to manual measurements in TETs.

A study of quantitative indicators for slice sorting in cine-mode 4DCT.

The uncertainties of four-dimensional computed tomography (4DCT), also called as residual motion artefacts (RMA), induced from irregular respiratory patterns can degrade the quality of overall radiotherapy. This study aims to quantify and reduce those uncertainties. A comparative study on quantitative indicators for RMA was performed, and based on this, we proposed a new 4DCT sorting method that is applicable without disrupting the current clinical workflow. In addition to the default phase sorting strategy, both additional amplitude information from external surrogates and the quantitative metric for RMA, investigated in this study, were introduced. The comparison of quantitative indicators and the performance of the proposed sorting method were evaluated via 10 cases of breath-hold (BH) CT and 30 cases of 4DCT. It was confirmed that N-RMSD (normalised root-mean-square-deviation) was best matched to the visual standards of our institute's regime, manual sorting method, and could accurately represent RMA. The performance of the proposed method to reduce 4DCT uncertainties was improved by about 18.8% in the averaged value of N-RMSD compared to the default phase sorting method. To the best of our knowledge, this is the first study that evaluates RMA indicators using both BHCT and 4DCT with visual-criteria-based manual sorting and proposes an improved 4DCT sorting strategy based on them.

Efficient Photon Extraction in Top-Emission Organic Light-Emitting Devices Based on Ampicillin Microstructures.

The desire to enhance the efficiency of organic light-emitting devices (OLEDs) has driven to the investigation of advanced materials with fascinating properties. In this work, the efficiency of top-emission OLEDs (TEOLEDs) is enhanced by introducing ampicillin microstructures (Amp-MSs) with dual phases (α-/ß-phase) that induce photoluminescence (PL) and electroluminescence (EL). Moreover, Amp-MSs can adjust the charge balance by Fermi level (EF ) alignment, thereby decreasing the leakage current. The decrease in the wave-guided modes can enhance the light outcoupling through optical scattering. The resulting TEOLED demonstrates a record-high external quantum efficiency (EQE) (maximum: 68.7% and average: 63.4% at spectroradiometer; maximum: 44.8% and average: 42.6% at integrating sphere) with a wider color gamut (118%) owing to the redshift of the spectrum by J-aggregation. Deconvolution of the EL intensities is performed to clarify the contribution of Amp-MSs to the device EQE enhancement (optical scattering by Amp-MSs: 17.0%, PL by radiative energy transfer: 9.1%, and EL by J-aggregated excitons: 4.6%). The proposed TEOLED outperforms the existing frameworks in terms of device efficiency.