Publications by authors named "Seung-Hyuk Lim"

Objectives: The occurrence of cognitive deficits after subarachnoid hemorrhage (SAH) is highly possible, leading to vascular dementia. We performed a novel longitudinal genome-wide association study (GWAS) to identify genetic modifications associated with cognitive impairment following SAH in a long-term prospective cohort study.

Materials And Methods: This GWAS involved 153 patients with SAH sharing 5,971,372 markers after high-throughput imputation.

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Object: We aimed to investigate the association of Haptoglobin (Hp) phenotypes with perihematomal edema (PHE) and neurological outcomes after intracerebral hemorrhage (ICH).

Methods: This prospective multicenter study enrolled patients that suffered ICH from March 2017 to February 2020. Hp phenotypes were determined using Western blotting; relative α1 intensity was calculated in patients with Hp2-1.

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Objective: The influence of moderate-to-severe traumatic brain injury (TBI) on acute pulmonary injury is well established, but the association between acute pulmonary injury and mild TBI has not been well studied. Here, we evaluated the histological changes and fluctuations in inflammatory markers in the lungs to determine whether an acute pulmonary inflammatory response occurred after mild TBI.

Methods: Mouse models of mild TBI (n=24) were induced via open-head injuries using a stereotaxic impactor.

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Article Synopsis
  • Copeptin shows promise as a predictive biomarker for neurologic outcomes in moderate traumatic brain injury (TBI) patients, specifically in those with a Glasgow Coma Scale (GCS) score of 9-12.
  • In a study involving 70 patients, higher copeptin levels were found to be independently associated with poor neurologic outcomes at 6 months, along with lower GCS scores and abnormal CT findings.
  • Copeptin levels measured on day 7 after the injury were more effective than C-reactive protein (CRP) in predicting these outcomes, suggesting its potential as a reliable prognostic tool.
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Background: To assess the association of haptoglobin (Hp) phenotype with neurological and cognitive outcomes in a large cohort of patients with subarachnoid hemorrhage (SAH).

Methods: This prospective multicenter study enrolled patients with aneurysmal SAH between May 2015 and September 2020. The Hp phenotype was confirmed Western blots.

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Group III-nitride semiconductor-based ultraviolet (UV) light emitting diodes have been suggested as a substitute for conventional arc-lamps such as mercury, xenon and deuterium arc-lamps, since they are compact, efficient and have a long lifetime. However, in previously reported studies, group III-nitride UV light emitting diodes did not show a broad UV spectrum range as conventional arc-lamps, which restricts their application in fields such as medical therapy and UV spectrophotometry. Here, we propose GaN quantum dots (QDs) grown on different facets of hexagonal truncated pyramid structures formed on a conventional (0001) sapphire substrate.

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The influence of thermal annealing on the properties of germanium grown on silicon (Ge-on-Si) has been investigated. Depth dependencies of strain and photoluminescence (PL) were compared for as-grown and annealed Ge-on-Si samples to investigate how intermixing affects the optical properties of Ge-on-Si. The tensile strain on thermally annealed Ge-on-Si increases at the deeper region, while the PL wavelength becomes shorter.

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The development of future 3D-printed electronics relies on the access to highly conductive inexpensive materials that are printable at low temperatures (<100 C). The implementation of available materials for these applications are, however, still limited by issues related to cost and printing quality. Here, we report on the simple hydrothermal growth of novel nanocomposites that are well suited for conductive printing applications.

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Control of the growth front in three-dimensional (3D) hexagonal GaN core structures is crucial for increased performance of light-emitting diodes (LEDs), and other photonic devices. This is due to the fact that InGaN layers formed on different growth facets in 3D structures exhibit various band gaps which originate from differences in the indium-incorporation efficiency, internal polarization, and growth rate. Here, a-plane {[Formula: see text] } facets, which are rarely formed in hexagonal pyramid based growth, are intentionally fabricated using mask patterns and adjustment of the core growth conditions.

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White light-emitting diodes (LEDs) are becoming an alternative general light source, with huge energy savings compared to conventional lighting. However, white LEDs using phosphor(s) suffer from unavoidable Stokes energy converting losses, higher manufacturing cost, and reduced thermal stability. Here, we demonstrate electrically driven, phosphor-free, white LEDs based on three-dimensional gallium nitride structures with double concentric truncated hexagonal pyramids.

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We report on the fabrication of novel InGaN nanowires (NWs) with improved crystalline quality and high radiative efficiency for applications as nanoscale visible light emitters. Pristine InGaN NWs grown under a uniform In/Ga molar flow ratio (UIF) exhibited multi-peak white-like emission and a high density of dislocation-like defects. A phase separation and broad emission with non-uniform luminescent clusters were also observed for a single UIF NW investigated by spatially resolved cathodoluminescence.

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Unlabelled: We fabricated 8-in. Si nanocone (NC) arrays using a nanoimprint technique and investigated their optical characteristics. The NC arrays exhibited remarkable antireflection effects; the optical reflectance was less than 10% in the visible wavelength range.

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