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We investigated the influence of oxygen deficiency on the Fermi level (EF) of ZnO thin film prepared by pulsed laser deposition (PLD). For this purpose, we adopted in situ x-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. The oxygen deficiency was effectively controlled by varying the oxygen partial pressure [P(O2)] during the PLD. The EF shifted by +0.6 eV as the P(O2) decreased from 10 to 3.3 Pa. This shift indicates a significant change in the energy balance in the oxygen-deficient ZnO films. This fact suggests that the very large change in the resistivity of ZnO thin films resulting from the oxygen deficiency could be attributed to the EF shift rather than grain boundary formation in the ZnO film. [ABSTRACT FROM AUTHOR]

The band alignment for atomic layer deposited (ZrO2)x(SiO2)1-x (x=1.0, 0.75, 0.5, 0.25) gate dielectric thin films grown on Si (100) was obtained by using x-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The band gap, conduction band offset, and the valence band offset for ZrO2 thin film were 5.30, 1.83, and 2.35 eV, respectively. These values for Zr silicates with x more than 0.5 are independent of SiO2 concentration but both holes and electrons have more symmetric barrier heights when x=0.25. The Zr silicate dielectrics are strongly affected by Zr–O nearest neighbor bonding. [ABSTRACT FROM AUTHOR]

La aluminate (La2O3)x(Al2O3)1-x films were grown by atomic layer deposition method, for which the conduction band offset, valence band offset, and band gap were obtained by using x-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The valence band offsets were nearly unchanged within the range from 2.23 to 2.37 eV with increasing Al content. The conduction band offsets were changed from 2.40 to 2.86 eV for the above dielectrics. Remarkably, the band gap could be engineered from 5.75 to 6.35 eV by increasing Al content. We also found that La aluminate films have symmetric band profiles. [ABSTRACT FROM AUTHOR]

We have investigated the interface states in HfO2/SiO2/Si(100) systems that were prepared by using the in situ pulsed laser deposition technique. X-ray photoelectron spectroscopy data revealed that when the HfO2 film thickness exceeds 11 Å, the film composition undergoes a systematic change from Hf silicate to oxygen-deficient HfOx<2. Furthermore, we determined that the evolution of the interface states clearly depends on the oxygen condition applied during the film growth and that the oxygen vacancy is an important parameter for Hf silicate formation. [ABSTRACT FROM AUTHOR]

We have investigated the electronic structure of transition-metal (TM=Sc, Y, Zr, and Nb)-doped Al[sub 2]O[sub 3] by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy (XAS). In valence bands of these TM-doped Al[sub 2]O[sub 3] measured by XPS, the highest occupied levels and the shapes of valence bands are almost unchanged from the pure alumina. On the other hand, XAS spectra obtained at the oxygen K-edge show that Nb- and Zr-doped Al[sub 2]O[sub 3] show localized d states in the bandgap below the conduction band minimum, while Y- and Sc-doped Al[sub 2]O[sub 3] have d states inside the conduction band of the original Al[sub 2]O[sub 3]. This implies that Y- and Sc-doped Al[sub 2]O[sub 3] will show little bandgap degradation and maintain the same band offset as silica at the Si interface, and can serve as promising candidates for an alternative gate oxide. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the real-world clinical outcomes of consolidative durvalumab in patients with unresectable locally advanced non-small cell lung cancer (LA-NSCLC) and to explore the role of radiotherapy in the era of immunotherapy. Materials and Methods: This retrospective study assessed 171 patients with unresectable LA-NSCLC who underwent concurrent chemoradiotherapy (CCRT) with or without consolidative durvalumab at Asan Medical Center between May 2018 and May 2021. Primary outcomes included freedom from locoregional failure (FFLRF), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS). Results: Durvalumab following CCRT demonstrated a prolonged median PFS of 20.9 months (p=0.048) and a 3-year FFLRF rate of 57.3% (p=0.008), compared to 13.7 months and 38.8%, respectively, with CCRT alone. Furthermore, the incidence of in-field recurrence was significantly greater in the CCRT-alone group compared to the durvalumab group (26.8% vs. 12.4%, p=0.027). While median OS was not reached with durvalumab, it was 35.4 months in patients receiving CCRT alone (p=0.010). Patients positive for programmed cell death ligand 1 (PD-L1) expression showed notably better outcomes, including FFLRF, DMFS, PFS, and OS. Adherence to PACIFIC trial eligibility criteria identified 100 patients (58.5%) as ineligible. The use of durvalumab demonstrated better survival regardless of eligibility criteria. Conclusion The use of durvalumab consolidation following CCRT significantly enhanced locoregional control and OS in patients with unresectable LA-NSCLC, especially in those with PD-L1-positive tumors, thereby validating the role of durvalumab in standard care. [ABSTRACT FROM AUTHOR]

Purpose The optimal treatment for patients with stage III non-small cell lung cancer (NSCLC) remains controversial. This study aimed to investigate prognostic factors and clinical outcome in stage III NSCLC using real-world clinical data in the Korean population. Materials and Methods Among 8,110 patients with lung cancer selected from 52 hospitals in Korea during 2014-2016, only patients with stage III NSCLC were recruited and analyzed. A standardized protocol was used to collect clinical information and Cox proportional hazards models were used to identify risk factors for mortality. Results A total of 1,383 patients (46.5% had squamous cell carcinoma and 40.9% had adenocarcinoma) with stage III NSCLC were enrolled, and their median age was 70 years. Regarding clinical stage, 548 patients (39.6%) had stage IIIA, 517 (37.4%) had stage IIIB, and 318 (23.0%) had stage IIIC. Pertaining to the initial treatment method, the surgery group (median survival period, 36 months) showed better survival outcomes than the non-surgical treatment group (median survival period, 18 months; p=0.001) in patients with stage IIIA. Moreover, among patients with stage IIIB and stage IIIC, those who received concurrent chemotherapy and radiation therapy (CCRT; median survival period, 24 months) showed better survival outcomes than those who received chemotherapy (median survival period, 11 months), or radiation therapy (median survival period, 10 months; p < 0.001). Conclusion While surgery might be feasible as the initial treatment option in patients with stage IIIA NSCLC, CCRT showed a beneficial role in patients with stage IIIB and IIIC NSCLC. [ABSTRACT FROM AUTHOR]

Abstract Understanding the degradation mechanism of organic light-emitting diodes (OLED) is essential to improve device performance and stability. OLED failure, if not process-related, arises mostly from chemical instability. However, the challenges of sampling from nanoscale organic layers and interfaces with enough analytical information has hampered identification of degradation products and mechanisms. Here, we present a high-resolution diagnostic method of OLED degradation using an Orbitrap mass spectrometer equipped with a gas cluster ion beam to gently desorb nanometre levels of materials, providing unambiguous molecular information with 7-nm depth resolution. We chemically depth profile and analyse blue phosphorescent and thermally-activated delayed fluorescent (TADF) OLED devices at different degradation levels. For OLED devices with short operational lifetimes, dominant chemical degradation mainly relate to oxygen loss of molecules that occur at the interface between emission and electron transport layers (EML/ETL) where exciton distribution is maximised, confirmed by emission zone measurements. We also show approximately one order of magnitude increase in lifetime of devices with slightly modified host materials, which present minimal EML/ETL interfacial degradation and show the method can provide insight for future material and device architecture development.

Leak detection in nuclear reactor coolant systems is crucial for maintaining the safety and operational integrity of nuclear power plants. Traditional leak detection methods, such as acoustic emission sensors and spectroscopy, face challenges in sensitivity, response time, and accurate leak localization, particularly in complex piping systems. In this study, we propose a novel leak detection approach that incorporates a rigid guide tube into the insulation layer surrounding reactor coolant pipes and combines this with an advanced detection criterion based on Frequency Center of Gravity shifts and Signal-to-Noise Ratio analysis. This dual-method strategy significantly improves the sensitivity and accuracy of leak detection by providing a stable transmission path for ultrasonic signals and enabling robust signal analysis. The rigid guide tube-based system, along with the integrated criteria, addresses several limitations of existing technologies, including the detection of minor leaks and the complexity of installation and maintenance. By enhancing the early detection of leaks and enabling precise localization, this approach contributes to increased reactor safety, reduced downtime, and lower operational costs. Experimental evaluations demonstrate the system’s effectiveness, focusing on its potential as a valuable addition to the current array of nuclear power plant maintenance technologies. Future research will focus on optimizing key parameters, such as the threshold frequency shift (Δf) and the number of randomly selected frequencies (N), using machine learning techniques to further enhance the system’s accuracy and reliability in various reactor environments.

Abstract In this study, the potential of Chlorella sorokiniana JD1-1 for biodiesel production was evaluated using domestic wastewater (DWW) as a diluent for locally-generated livestock wastewater (LWW). This strategy aimed to provide sustainable wastewater treatment, reduce environmental impacts, enhance cost-effectiveness, and promote biodiesel production. LWW was diluted with tap water and DWW at ratios of 75%, 50%, and 25% (v/v), and the effects on microalgal growth, nutrient removal efficiency, and lipid yield were evaluated. Although the maximum biomass concentration was observed in the artificial growth medium (BG-11) (1170 mg L−1), 75% dilution using tap water (610 mg L−1) and DWW (780 mg L−1) yielded results comparable to the exclusive use of DWW (820 mg L−1), suggesting a potential for substitution. Total nitrogen (TN) removal rates were consistently high under all conditions, particularly in samples with higher concentrations of LWW. Conversely, total phosphorus (TP) concentrations decreased under most conditions, although some displayed large increases. Further studies are necessary to optimize the nutrient balance while maintaining economic feasibility and maximizing biodiesel production.

This paper introduces the novel design and implementation of a low-power wireless monitoring system designed for nuclear power plants, aiming to enhance safety and operational efficiency. By utilizing advanced signal-processing techniques and energy-efficient technologies, the system supports real-time, continuous monitoring without the need for frequent battery replacements. This addresses the high costs and risks associated with traditional wired monitoring methods. The system focuses on acoustic and ultrasonic analysis, capturing sound using microphones and processing these signals through heterodyne frequency conversion for effective signal management, accommodating low-power consumption through down-conversion. Integrated with edge computing, the system processes data locally at the sensor level, optimizing response times to anomalies and reducing network load. Practical implementation shows significant reductions in maintenance overheads and environmental impact, thereby enhancing the reliability and safety of nuclear power plant operations. The study also sets the groundwork for future integration of sophisticated machine learning algorithms to advance predictive maintenance capabilities in nuclear energy management.

Objects adrift can cause considerable damage to coastal infrastructure and property during tsunami and storm surge events. Despite the potential for harm, the drifting behavior of these objects remains poorly understood, thereby hindering effective prediction and mitigation of collision damage. To address this gap, this study employed a motion analysis program to track a drifting container's location using images from an existing laboratory experiment. The container's trajectory and velocity were calculated based on the positions of five markers strategically placed at its four corners and center. Our findings indicate that the container's maximum drift velocity and distance are directly influenced by the scale of the solitary wave and inversely related to the container's weight. Specifically, heavier containers are less likely to be displaced by solitary waves, while larger waves can damage coastal structures more. This study offers new insights into container drift behavior induced by solitary waves, with implications for enhancing coastal infrastructure design and devising mitigation strategies to minimize the risk of collision damage.

Background: Although acute exacerbation (AE) after treatment for lung cancer (LC) is a poor prognostic factor in patients with interstitial lung disease associated with lung cancer (ILD-LC), the risk of AE according to cancer treatment type remains unclear. Therefore, in the present study, we aimed to investigate the association between AE and treatment received for LC in patients with ILD-LC. Methods: We conducted a retrospective study of patients with ILD-LC who had undergone treatment for LC between January 2018 and December 2022. The primary study outcome was the incidence of AE within 12 months of treatment for LC according to treatment type. The association between AE and all-cause mortality was evaluated as a secondary outcome. Results: Among a total of 137 patients, 23 (16.8%) developed AE within 12 months of treatment for LC. The incidence of AE according to treatment type was 4.3% for surgery, 16.2% for radiotherapy, 15.6% for chemotherapy, and 54.5% for concurrent chemoradiation therapy (CCRT). Patients who received CCRT were more likely to develop AE, even after adjustment for covariables (hazard ratio [HR], 15.39; 95% confidence interval [CI]: 4.00–59.19; p < 0.001). In addition, AE within 12 months of treatment for LC was associated with an increased risk of all-cause mortality (HR, 2.82; 95% CI: 1.13–7.04; p = 0.026). Conclusion: Among treatment options for patients with ILD-LC, CCRT was associated with an increased risk for AE. In addition, patients with AE had a higher mortality rate than patients without AE. [ABSTRACT FROM AUTHOR]

Purpose We aimed to investigate the feasibility of four criteria on oligometastasis (OM) concerning clear survival benefits of local therapy (LT) during tyrosine kinase inhibitor (TKI) treatment in non-small cell lung cancer (NSCLC). Materials and Methods This single-center, retrospective study included patients with advanced NSCLC who received LT because of OM during TKI treatment at Asan Medical Center from January 2011 to December 2020. At the application of LT OM was classified according to four criteria: TNM, European Organization for Research and Treatment of Cancer Lung Cancer Group (EORTC-LCG), National Comprehensive Network (NCCN), and ORGAN. We compared survival outcomes between patients with and without OM. Results The median overall survival of the 117 patients included in the analysis was 70.8 months (95% confidence interval [CI], 56.6 to 85.1). The patients with OM meeting all four criteria (hazard ratio [HR] with 95% CI of TNM criteria 0.24 with 0.10-0.57; p=0.001, EORTC-LCG criteria 0.34 with 0.17-0.67; p=0.002, NCCN criteria 0.41 with 0.20-0.86; p=0.018 and ORGAN criteria 0.33 with 0.18-0.60; p < 0.001) had significantly longer survival compared with patients who did not after adjusting for confounding factors. Furthermore, increasing the number of extra-thoracic metastatic organs to two or more were independent predictive factors for worse survival outcomes (2 organs: HR, 3.51; 95% CI, 1.01 to 12.14; p=0.048; 3 organs: HR, 4.31; 95% CI, 0.94 to 19.73; p=0.060; 4 organs: HR, 24.47; 95% CI, 5.08 to 117.80; p < 0.001). Conclusion Patients with OM defined by all four criteria showed prognostic benefits from LT during TKI therapy. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study is to evaluate the safety and efficacy of ex vivo activated and expanded natural killer (NK) cell therapy (SNK01) plus pembrolizumab in a randomized phase I/IIa clinical trial. Materials and Methods Overall, 18 patients with advanced non-small cell lung cancer (NSCLC) and a programmed death ligand 1 tumor proportion score of 1% or greater who had a history of failed frontline platinum-based therapy were randomized (2:1) to receive pembrolizumab every 3 weeks +/- 6 weekly infusions of SNK01 at either 2x109 or 4x109 cells per infusion (pembrolizumab monotherapy vs. SNK01 combination). The primary endpoint was safety, whereas the secondary endpoints were the objective response rate (ORR), progression-free survival (PFS), overall survival, and quality of life. Results Since no dose-limiting toxicity was observed, the maximum tolerated dose was determined as SNK01 4x109 cells/dose. The safety data did not show any new safety signals when SNK01 was combined with pembrolizumab. The ORR and the 1-year survival rate in the NK combination group were higher than those in patients who underwent pembrolizumab monotherapy (ORR, 41.7% vs. 0%; 1-year survival rate, 66.7% vs. 50.0%). Furthermore, the median PFS was higher in the SNK01 combination group (6.2 months vs. 1.6 months, p=0.001). Conclusion Based on the findings of this study, the NK cell combination therapy may consider as a safe treatment method for stage IV NSCLC patients who had a history of failed platinum-based therapy without an increase in adverse events. [ABSTRACT FROM AUTHOR]

Among many pipes in a nuclear power plant, the spray pipes in the reactor building are one of the most important pipes in view of their function and safety aspects. However, it is very difficult to manually reach and inspect the pipes for defects or damage, because these pipes are installed in very high places. To carry out this kind of inspection more easily, we developed a mobile robot to climb up and down and to cross over such pipes. A mobile robot should be small and light enough that it can be practically and safely operated in a nuclear power plant. Our robot is able to overcome obstacles such as valves, pipe flanges, and T-shaped branches, and it also meets the requirements of fail-safe, autonomous grasping, and self-power without the cables to the remote control station. The robot has a five-degree-of-freedom manipulator and two grippers and moves along the cylindrical pipes bypassing the obstacles. The robot should be able to grasp the next pipe autonomously, because the robot works in places high off the ground where the remote operator cannot see the next pipe for the robot to grasp. This article proposes a vision-based scheme for grasping a cylindrical pipe semi-autonomously and describes its solution along with the forward kinematics and inverse kinematics of the mobile robot. The configuration of the pipe-climbing robot, including its hardware and software, is described, and the robot control with visual grasping is explained. The robot can be used practically for spray-pipe inspection as well as many potential other applications, such as inspection of the roof frame of a stadium consisting of pipes.

We have developed an electronics circuit that generates a high voltage with a frequency of 0.3–2 MHz to build an electro therapy system that can optimize tissue heating characteristics. These characteristics are used in medical applications. This paper is focused on the analysis of high frequency electro-therapy system to optimize tissue heating with the help of a high voltage pulse signal, which peak voltage is almost 2 kV. This optimized tissue heating between the inner tissue and the thermal distributions has examined in terms of frequency and voltage. The target tissue heating is composed of a single electrode in an experiment that has especially conducted to find the tissue heating characteristics. In the end, a new method for electro-therapy is developed, which is applicable to a specific tissue depth.

The efficacy of EGFR-tyrosine kinase inhibitors (TKIs) is significantly limited by various resistance mechanisms to those drugs. The resistance to EGFR-TKI is largely divided by two classes; acquired resistance after EGFR-TKI treatment, and primary resistance marked by cancer cell's dependence on other oncogene, such as KRAS. YAP has emerged as critical oncogene in conferring drug resistance against targeted therapy. In this study, we evaluated the role of YAP in primary and acquired EGFR-TKI resistance using gefitinib-resistant A549 and PC9 cells and their parental cell lines. Our study revealed that EGFR-TKI resistance is associated with enhanced YAP activity. Notably, YAP activation was independent of the Hippo pathway. We confirmed that AXL is a downstream target of YAP that confers EGFR-TKI resistance. And our results showed that YAP can induce ERK activation in lung adenocarcinoma. The combination of YAP inhibition with EGFR-TKI overcomes primary and acquired EGFR-TKI resistance. We also found increased YAP expression in human lung cancer after acquiring EGFR-TKI resistance. Collectively, we suggest a novel EGFR-TKI resistance mechanism involving YAP activation and suggest targeting YAP and EGFR simultaneously may be a breakthrough treatment of primary and acquired EGFR-TKI resistant lung cancer. [ABSTRACT FROM AUTHOR]

In non--small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations, acquired resistance to EGFR-tyrosine kinase inhibitors (EGFR-TKI) can occur through a generation of bypass signals such as MET or AXL activation. In this study, we investigated the antitumor activity of NPS-1034, a newly developed drug that targets both MET and AXL, in NSCLC cells with acquired resistance to gefitinib or erlotinib (HCC827/GR and HCC827/ER, respectively). Characterization of H820 cells and evaluation of NPS-1034 efficacy in these cells were also performed. The resistance of HCC827/GR was mediated by MET activation, whereas AXL activation led to resistance in HCC827/ER. The combination of gefitinib or erlotinib with NPS-1034 synergistically inhibited cell proliferation and induced cell death in both resistant cell lines. Accordingly, suppression of Akt was noted only in the presence of treatment with both drugs. NPS-1034 was also effective in xenograft mouse models of HCC827/GR. Although the H820 cell line was reported previously to have T790M and MET amplification, we discovered that AXL was also activated in this cell line. There were no antitumor effects of siRNA or inhibitors specific for EGFR or MET, whereas combined treatment with AXL siRNA or NPS-1034 and EGFR-TKIs controlled H820 cells, suggesting that AXL is the main signal responsible for resistance. In addition, NPS-1034 inhibited cell proliferation as well as ROS1 activity in HCC78 cells with ROS1 rearrangement. Our results establish the efficacy of NPS-1034 in NSCLC cells rendered resistant to EGFR-TKIs because of MET or AXL activation or ROS1 rearrangement. [ABSTRACT FROM AUTHOR]