Publications by authors named "Ungsoo Kim"

Article Synopsis
  • MPTMS was tested as a surface modifier for AlO powder to explore its impact on the properties of photocurable composite slurries used in 3D printing.
  • Lower concentrations of MPTMS (2 wt.% and 5 wt.%) enhanced the slurry's stability and photocuring rates, while higher concentrations (10 wt.% and 20 wt.%) led to reduced stability and structural defects.
  • The study concluded that 5 wt.% MPTMS is optimal for achieving stable and robust printed structures, with significant effects on the slurries' rheological properties and printing performance.
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Mesoporous structured electron transport layers (ETLs) in perovskite solar cells (PSCs) have an increased surface contact with the perovskite layer, enabling effective charge separation and extraction, and high-efficiency devices. However, the most widely used ETL material in PSCs, TiO, requires a sintering temperature of more than 500 °C and undergoes photocatalytic reaction under incident illumination that limits operational stability. Recent efforts have focused on finding alternative ETL materials, such as SnO.

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To investigate the efficacy of the Korean version of the Minnesota low vision reading chart. A Korean version consisting of 38 items was prepared based on the MNREAD acuity chart developed by the University of Minnesota. A linguist composed the representative sentences, each containing nine words from second and third grade levels of elementary school.

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Water electrolysis is emerging as a promising renewable-energy technology for the green production of hydrogen, which is a representative and reliable clean energy source. From economical and industrial perspectives, the development of earth-abundant non-noble metal-based and bifunctional catalysts, which can simultaneously exhibit high catalytic activities and stabilities for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is critical; however, to date, these types of catalysts have not been constructed, particularly, for high-current-density water electrolysis at the industrial level. This study developed a heterostructured zero-dimensional (0D)-one-dimensional (1D) PrBaSrCoFeO (PBSCF)-NiS as a self-supported catalytic electrode via interface and morphology engineering.

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Objectives: To investigate the morphological characteristics of Bergmeister papilla (BMP), a persistent hyaloid remnant tissue, and its effects on the measurements and repeatability of spectral-domain optical coherence tomography (OCT).

Subjects/methods: The subjects of this prospective cross-sectional study including 83 patients with BMP and 76 unaffected individuals, all had open-angle structures. Images, including a 5-line raster and three consecutive optic disc cube scans centred on the optic disc, were acquired using the Cirrus high-definition OCT.

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The introduction of heteroatoms is a widely employed strategy for electrocatalysis of transition metal dichalcogenides (TMDs). This approach activates the inactive basal plane, effectively boosting the intrinsic catalytic activity. However, the effect of atomic configurations incorporated within the TMDs' lattice on catalytic activity is not thoroughly understood owing to the lack of controllable synthetic approaches for highly doped TMDs.

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Background: To report the clinical manifestations of non-arteritic anterior ischemic optic neuropathy (NAION) cases after coronavirus disease 2019 (COVID-19) vaccination in Korea.

Methods: This multicenter retrospective study included patients diagnosed with NAION within 42 days of COVID-19 vaccination. We collected data on vaccinations, demographic features, presence of vascular risk factors, ocular findings, and visual outcomes of patients with NAION.

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Mutations in the RPE65 gene, associated with Leber congenital amaurosis, early-onset severe retinal dystrophy, and retinitis pigmentosa, gained growing attention since gene therapy for patients with RPE65-associated retinal dystrophy is available in clinical practice. RPE65 gene accounts for a very small proportion of patients with inherited retinal degeneration, especially Asian patients. Because RPE65-associated retinal dystrophy shares common clinical characteristics, such as early-onset severe nyctalopia, nystagmus, low vision, and progressive visual field constriction, with retinitis pigmentosa by other genetic mutations, appropriate genetic testing is essential to make a correct diagnosis.

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To investigate differences in clinical features based on magnetic resonance imaging (MRI) in idiopathic isolated optic neuritis patients. We retrospectively analyzed 68 eyes of 59 patients diagnosed with optic neuritis and showed inflammatory findings indicative of optic neuritis on MRI. We investigated clinical features, such as the presence of accompanying pain, visual acuity, and optic disc swelling.

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The design of the Korean traditional distiller '' was extracted as a digital sketch, and the internal fluid flow in the distillation process was tracked through computer simulation. Based on this, a new design was derived to improve distillation efficiency and its changes were researched. The ethanol particles vaporized inside the distiller were stagnated or their discharge was accelerated according to the magnitude and frequency of vortex.

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Purpose: To describe clinical manifestations and short-term prognosis of ocular motility disorders following coronavirus disease-2019 (COVID-19) vaccination.

Methods: Ocular motility disorders were diagnosed by clinical assessment, high-resolution magnetic resonance imaging, and laboratory testing. Clinical manifestations, short-term prognosis, and rate of complete recovery were analyzed.

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Purpose: To investigate the surgical results of the non-adjustable suture technique under general anesthesia for the correction of acute acquired comitant esotropia.

Study Design: Retrospective case study.

Methods: Patients with acute acquired comitant esotropia who underwent corrective surgery from September 2008 to June 2018 were included.

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Purpose: To investigate the current status of electrophysiological test use in ophthalmology.

Methods: We analyzed 1057 electrophysiological tests conducted at Kim's Eye Hospital from January 1 to December 31, 2018. The included tests were electroretinogram (full-field, multifocal, and pattern ERG), electrooculogram (EOG), and visual evoked potential (pattern and flash VEP).

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Ceramic polymer composite slurries were prepared using nano- and micro-sized Al2O3 in order to analyze rheological properties, sedimentation, and curing behavior. Slurries with different Al2O3 particle sizes were prepared with varying concentrations of photoinitiator, and subjected to different exposure times to prepare a printing object. All slurries exhibit shear-thinning behavior, and the viscosity increases with decreasing Al2O3 particle size.

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To investigate the factors for treatment success in anisometropic amblyopia according to the spherical equivalent (SE) type of amblyopic eyes. Medical records of 397 children with anisometropic amblyopia aged 3 to 12 years who presented in a secondary referral eye hospital during 2010 ~ 2016 were retrospectively reviewed. Anisometropia was defined as ≥ 1 diopter (D) difference in SE, or ≥ 1.

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Purpose: This study aimed to investigate the surgical outcomes of nonadjustable Harada-Ito surgery under general anesthesia.

Methods: Twenty-two patients who underwent nonadjustable modified Harada-Ito surgery under general anesthesia were reviewed retrospectively. Among them, 21 out of the 22 patients who were followed up for 6 months after surgery were included in this study.

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Pathogenic variants cause a rare autosomal dominant neurodevelopmental disorder referred to as the Bosch-Boonstra-Schaaf Optic Atrophy Syndrome. Although visual loss is a prominent feature seen in affected individuals, the molecular and cellular mechanisms contributing to visual impairment are still poorly characterized. We conducted a deep phenotyping study on a cohort of 22 individuals carrying pathogenic variants to document the neurodevelopmental and ophthalmological manifestations, in particular the structural and functional changes within the retina and the optic nerve, which have not been detailed previously.

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The operating principle of conventional water electrolysis using heterogenous catalysts has been primarily focused on the unidirectional charge transfer within the heterostructure. Herein, multidirectional charge transfer concept has been adopted within heterostructured catalysts to develop an efficient and robust bifunctional water electrolysis catalyst, which comprises perovskite oxides (LaSrCoO, LSC) and potassium ion-bonded MoSe (K-MoSe). The complementary charge transfer from LSC and K to MoSe endows MoSe with the electron-rich surface and increased electrical conductivity, which improves the hydrogen evolution reaction (HER) kinetics.

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Retinal ganglion cells (RGCs) are the bridging neurons that connect the retinal input to the visual processing centres within the central nervous system. There is a remarkable diversity of RGCs and the various subtypes have unique morphological features, distinct functions, and characteristic pathways linking the inner retina to the relevant brain areas. A number of psychophysical and electrophysiological tests have been refined to investigate this large and varied population of RGCs.

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Purpose: To compare a biometer using swept-source optical coherence tomography (SS-OCT) with a partial coherence interferometry (PCI)-based biometer in measurements of two ocular biometry parameters, i.e., the axial length and anterior cornea curvature.

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Dominant optic atrophy (DOA) is an inherited mitochondrial disease leading to specific degeneration of retinal ganglion cells (RGCs), thus compromising transmission of visual information from the retina to the brain. Usually, DOA starts during childhood and evolves to poor vision or legal blindness, affecting the central vision, whilst sparing the peripheral visual field. In 20% of cases, DOA presents as syndromic disorder, with secondary symptoms affecting neuronal and muscular functions.

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Transition metal dichalcogenides (TMDs), due to their fascinating properties, have emerged as potential next-generation semiconducting nanomaterials across diverse fields of applications. When combined with other material systems, precise control of the intrinsic properties of the TMDs plays a vital role in maximizing their performance. Defect-induced atomic doping through introduction of a chalcogen vacancy into the TMDs lattices is known to be a promising strategy for modulating their characteristic properties.

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