University of Ulsan Open Access Korea
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    The association between symptoms of developmental coordination disorder and neuropsychological characteristics in children with and without ADHD

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    Objective: Attention-deficit/hyperactivity disorder (ADHD) frequently co-occurs with developmental coordination disorder (DCD). This study aimed to evaluate the association between DCD symptoms and neuropsychological characteristics in children with and without ADHD. Methods: We recruited 298 children aged 5-12 years. Motor performance was assessed using the Developmental Coordination Disorder Questionnaire (DCDQ), while ADHD symptoms were assessed using the ADHD Rating Scale (ARS) and the Advanced Test of Attention (ATA). Cognitive characteristics were measured using the Wechsler Intelligence Scale, and behavioral characteristics were assessed using the Korean Personality Rating Scale for Children. Results: The children had a mean age of 7.6 ± 1.7 years, with 214 (71.8%) being boys. Among children diagnosed with ADHD (n = 176), 39.2% exceeded the DCDQ cutoff score, compared to 4.1% in the neurotypical group (n = 122). In the correlation analysis, the DCDQ total score was significantly correlated with ARS, omission and commission errors in visual and auditory ATA, and full-scale intellectual quotient. In addition, symptoms of depression, social dysfunction, and psychosis were correlated with the DCDQ total score. In the between-group analysis, children with both ADHD and DCD exhibited more omission errors on the auditory ATA and behavioral problems related to depression, social dysfunction, and psychosis compared to children with ADHD only. Conclusion: Our study indicates that children with ADHD exhibit more difficulties in motor performance. Children with both ADHD and DCD may present with a greater burden of psychiatric conditions than children with ADHD only, suggesting the need for careful monitoring in clinical practice

    Holistic approach for fabrication of superhydrophobic MXene-based membrane for enhanced membrane distillation

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    There is growing interest in membrane distillation (MD) as a means of desalinating seawater with 100 % theoretical salt rejection which has the capacity to address freshwater scarcity. MD has huge potential for commercial applications owing to its low operating temperature and pressure requirements. However, wetting polymeric membranes inhibits water permeance and lowers salt rejection. MXene nanosheet-incorporated polyvinylidene (PVDF) membranes have been constructed for enhanced vapor transport with high water repellence and antiwetting properties. MXene nanosheets in PVDF polymeric matrices are responsible for their high super-hydrophobicity, which can mitigate membrane fouling and wetting during the MD process. As far as experimental outcomes are concerned, the pristine PVDF membrane exhibited severe wetting with salt leakage. Ti3C2Tx MXene nanosheets allow the formation of hierarchical polymeric micro/nanostructures, changing the intrinsic hydrophilicity to super-hydrophobicity. Surface engineering of a PVDF membrane with MXene nanosheets enables efficient saline desalination during the MD process. The surface-engineered MXene/PVDF membrane demonstrated a high-water contact angle of 143° with extremely high self-cleaning characteristics as compared to that of pristine PVDF membrane. As far as the performance of the membrane is concerned, the water flux of the pristine PVDF membrane decreased from 6.5 LMH to 6 LMH after the 14th hour which can be attributed to partial pores wetting during MD operation. Eventually, the pristine PVDF membrane exhibited a continuous salt flux (SF) increase. However, MXene/PVDF membrane showed stable water flux (8 LMH) and negligible SF. The study therefore demonstrates a facile and holistic approach for constructing MXene-based PVDF membranes that exhibit superior antiwetting performance during MD operation

    Prioritization of Injury Prevention and Management Programs and Research and Development (R&D) Projects: Survey Using the Delphi Technique and Analytic Hierarchy Process

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    We prioritized injury prevention and management programs, and research and development (R&D) projects using the Delphi method and analytic hierarchy process (AHP) for national plan. We summarized 21 programs and 31 R&D projects based on opinions collected in the opinion survey and brainstorming. Expert panel evaluated program and project relevance in the two Delphi rounds to make consensus. Total scores were calculated by adding criterion weights calculated through the AHP multiplied by the average of scores for each program and project. The top three programs were "Integrated Management System for Injury Data," "Comprehensive Injury Surveillance System," and "Transport System Improvement Program for Major Trauma." The top three R&D projects were researches on "Identification of Vulnerable Workers Injuries to Strengthen Protections," "Data Integration on Injury and Disability," and "Using Public Health Big Data to Identify Injury Status and Risk Factors." Experts highly rated the programs to improve injury surveillance system

    Impact of the Hexagonal Phase on Multiphoton-Absorption Properties of Mixed-Cation Halide Perovskite: FA0.8MA0.2PbI3

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    Recently, mixed-cation halide perovskites have gained significant attention for developing stable, high-performance solar cells. However, their nonlinear optical (NLO) properties are much less explored. Herein, this study reports on intriguing NLO properties observed from FA0.8MA0.2PbI3 single crystals, having an ideal bandgap of 1.52 eV for photovoltaic performance. Contrary to a simple prediction, the perovskite exhibits higher-order multiphoton absorption (MPA) over a broad wavelength range from 1300 to 1710 nm as evidenced by wavelength- and intensity-dependent photoluminescence measurements. The corresponding MPA coefficients are very large to dominate lower-order ordinary MPA across the bandgap. The hexagonal phase present in the perovskite is responsible for the observed higher-order transition as confirmed by the recovery of ordinary MPA in the absence of the hexagonal phase. Although the perovskite is known to crystallize into the cubic phase at room temperature, these results indicate that minor inclusion of the hexagonal phase (≈4.0% at room temperature) can drastically alter the nature of the multiphoton process by double resonance uniquely offered by the mixed phases

    Immune Checkpoint Inhibitor Score Predicts Survival Benefit of Immunotherapy in Patients with Non-small Cell Lung Cancer

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    Background: The use of immune checkpoint inhibitors (ICIs) in patients with advanced lung cancer is increasing. Despite ongoing studies to predict the efficacy of ICIs, its use in clinical practice remains difficult. Thus, we aimed to discover a predictive marker by analyzing blood cell characteristics and developing a scoring system for patients treated with ICIs. Methods: This was a prospective multicenter study in patients with advanced nonsmall cell lung cancer (NSCLC) who received ICIs as second-line treatment from June 2021 to November 2022. Blood cell parameters in routine blood samples were evaluated using an automated hematology analyzer. Immune checkpoint inhibitor score (IChIS) was calculated as the sum of neutrophil count score and immature granulocyte score. Results: A total of 143 patients from four institutions were included. The treatment response was as follows: partial response, 8.4%; stable disease, 37.1%; and progressive disease, 44.8%. Median progression-free survival and overall survival after ICI treatment was 3.0 and 8.3 months, respectively. Median progression-free survival in patients with an IChIS of 0 was 4.0 months, which was significantly longer than 1.9 months in patients with an IChIS of 1 and 1.0 month in those with an IChIS of 2 (p=0.001). The median overall survival in patients with an IChIS of 0 was 10.2 months, which was significantly longer than 6.8 and 1.8 months in patients with an IChIS of 1 and 2, respectively (p<0.001). Conclusion: Baseline IChIS could be a potential biomarker for predicting survival benefit of immunotherapy in NSCLC

    Predictors of malignancy for treatment direction in patients with nonfunctioning adrenal incidentaloma

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    Background: Adrenal incidentalomas (AI) are predominantly nonfunctional and benign, and their detection and differential diagnosis are aided by computed tomography (CT). A nonfunctioning adrenal incidentaloma (NFAI) usually requires regular follow-up; however, adrenalectomy may be necessary in certain patients. This study aimed to evaluate prognostic predictors to guide the treatment approach for AIs. Methods: This retrospective, single-center study involved patients diagnosed with NFAI from January 2000 to December 2020. Patients were divided into surgery and observation groups. A subgroup analysis compared malignant and benign adenoma within the surgery group. Results: A total of 307 patients were included, with 127 in the surgery group and 180 in the observation group. The surgery group displayed distinct morphological and malignant potential features in CT scans more frequently than the observational group did. The malignant subgroup exhibited more irregular borders on CT, and a higher number of patients with absolute washout under 60 % and relative washout under 40 % compared with the benign adenoma subgroup. Interestingly, within the surgery group, the mean tumor size was <4 cm for the both malignant and benign adenoma subgroups. Conclusions: Characterizing NFAI is important for appropriate treatment, as not all AIs have a favorable prognosis. CT findings associated with malignant potential, such as Hounsfield unit and washout values, were useful in determining the need for surgical treatment. However, the conventional criterion of a 4-cm size threshold for surgery was not a reliable malignancy predictor. Surgical resection should be considered for specific patient groups to ensure proper treatment over mere observation

    An automated quality assurance system with deep learning for small cube-ball phantom localization in noisy megavoltage images

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    To enhance efficiency and minimize errors, we automated the quality assurance (QA) process in radiation oncology, specifically laser localization. Additionally, we explored the use of a convolutional neural network (CNN) to enhance the detection of small cube-ball phantoms in noisy images. Laser localizations were measured manually on the acquired images. To automate the QA workflow, we developed a Linux server equipped with database and web servers. Digital Imaging and Communications in Medicine (DICOM) files were retrieved 40 times for 10 linear accelerators (LINACs). The center of the cube-ball phantoms was estimated through Gaussian fitting. We applied CNN using 6,968 stored results to improve the estimation performance in noisy megavoltage (MV) images. Subsequently, both analysis time and accuracy were compared. Our hospital has been employing the automated QA system since 2018, notably reducing the time for laser localization from 30 min to just 1 min. The average and standard deviation (SD) of inter-observer variability in the X- and Y-axes were 0.06 ± 0.01 mm and 0.05 ± 0.01 mm, respectively. Absolute differences between manual assessment and Gaussian fitting presented average and SD values of 0.40 ± 0.51 mm and 0.23 ± 0.24 mm, respectively. In contrast, absolute differences between manual assessment and CNN presented average and SD values of 0.12 ± 0.10 mm and 0.11 ± 0.09 mm, respectively. Overall, the automated QA system significantly hastened procedures in our large hospital and improved the estimation of the cube-ball phantom’s position in noisy images through deep learning

    Ultrapure gold recovery from electronic waste as nanoparticles immobilized in hydrogel matrix

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    Solid-supported gold nanoparticles possess significant value as economical and eco-friendly catalysts due to their durability and reusability. Conventional methods to synthesize heterogeneous catalysts require the use of expensive gold precursors, diminishing their economic viability. Recovering gold directly as nanoparticles immobilized in a solid matrix from electronic waste (e-waste) provides a promising economic solution. However, the greater abundance of other metal ions in e-waste solutions makes this task challenging, demanding more selective approaches. This study presents a cost-effective one-pot synthesis of gold nanoparticles immobilized in a hydrogel matrix from e-waste solutions, circumventing the need for gold precursors. The fabricated hydrogel exhibits exceptionally selective gold reduction, producing well-distributed and highly pure (23.78 K) gold nanoparticles inside the hydrogel matrix. The fine control in nanoparticle diameters from 22 to 35 nm was achieved by tuning the monomer compositions of the hydrogel. These hydrogel-supported gold nanoparticles demonstrate reusable catalytic properties, indicating their potential sustainability and industrial compatibility. This approach addresses the economic challenges of synthesizing solid-supported gold nanoparticles and offers a sustainable pathway

    Contrast-Enhanced T1-Weighted Magnetic Resonance Cholangiography Using Gadoxetate Disodium in Potential Living Liver Donors: Qualitative and Quantitative Improvement with 3-hour Delayed Imaging

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    Background: Contrast-enhanced T1-weighted magnetic resonance cholangiography (CE-T1-MRC) after gadoxetate disodium administration can be used for preoperative evaluation of the bile ducts in live liver donors. This study aimed to determine whether CE-T1-MRC with 3-hour delayed imaging improves bile duct visualization both qualitatively and quantitatively compared with 20-minute delayed imaging in potential living liver donors. Methods: We retrospectively identified 33 potential living liver donors (mean age, 30.1 years; 18 men and 15 women) who underwent preoperative CE-T1-MRC with both 20-minute delayed and 3-hour delayed imaging in a single session. The radiologist scored biliary visualization for right and left hepatic ducts (RHD and LHD), their secondary confluences and segmental bile ducts, common hepatic duct (CHD), and cystic duct (CD), and measured relative contrast ratio (rC) and relative signal intensity (rS) for RHD, LHD, and CHD. The data were analyzed using Wilcoxon's signed-rank test and paired t-test. Results: In qualitative analysis, duct visualization scores for RHD and LHD, their secondary confluences and segmental bile ducts, CHD, and CD were significantly higher on CE-T1-MRC with 3-hour delayed imaging than with 20-minute delayed imaging (all, P ≤ .046). In quantitative analysis, both rC and rS of RHD, LHD, and CHD were significantly higher on CE-T1-MRC with 3-hour delayed imaging than with 20-minute delayed imaging (all, P < .001). Conclusions: CE-T1-MRC with 3-hour delay imaging improves bile duct visualization both qualitatively and quantitatively in potential living liver donors

    An Enhanced Extremum Seeking-Based Energy Management Strategy with Equivalent State for Hybridized-Electric Tramway-Powered by Fuel Cell-Battery-Supercapacitors

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    This article proposes a novel real-time optimization-based energy management strategy (EMS) for proton membrane exchange fuel cell (PEMFC)-battery-supercapacitors-driven hybridized-electric tramways (HETs). The proposed algorithm is derived based on an enhanced extremum seeking (ES) algorithm, with a new equivalent state-of-charge (SOC) and a new adaptive co-state introduced. Thereby, optimized reference power for each power source can be distributed appropriately when using three components. The workability and prominent of the proposed technique are demonstrated through comparative simulations with fuzzy-rule-based EMS (FEMS) and equivalent consumption minimization strategy (ECMS) in two case studies: with and without considering the supercapacitors, as an important factor in the EMS design to stabilize the SOC of energy storage devices (ESDs). Briefly, under the proposed ES-based method, the PEMFC power can be regulated such that high-efficiency can be performed, approximately by 46.7%. Subsequently, the hydrogen consumption is reduced about 31.2% compared to a comparative fuzzy-based EMS. Besides, the supplements’ SOCs at the end of a driving cycle are also regulated to be equal to the initial ones

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