45 results on '"Park, Jeonghoon"'
Search Results
2. Wide field-of-hearing metalens for aberration-free sound capture
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Lee, Dongwoo, Oh, Beomseok, Park, Jeonghoon, Moon, Seong-Won, Shin, Kilsoo, Kim, Sea-Moon, and Rho, Junsuk
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- 2024
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3. Scalable manufacturing of high-index atomic layer–polymer hybrid metasurfaces for metaphotonics in the visible
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Kim, Joohoon, Seong, Junhwa, Kim, Wonjoong, Lee, Gun-Yeal, Kim, Seokwoo, Kim, Hongyoon, Moon, Seong-Won, Oh, Dong Kyo, Yang, Younghwan, Park, Jeonghoon, Jang, Jaehyuck, Kim, Yeseul, Jeong, Minsu, Park, Chanwoong, Choi, Hojung, Jeon, Gyoseon, Lee, Kyung-il, Yoon, Dong Hyun, Park, Namkyoo, Lee, Byoungho, Lee, Heon, and Rho, Junsuk
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- 2023
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4. Non-target screening of volatile organic compounds in spray-type consumer products and their potential health risks
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Yun, Hyejin, Park, Jeonghoon, Kim, Moon-Kyung, Yoon, Chungsik, Lee, Kiyoung, and Zoh, Kyung-Duk
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- 2023
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5. The combination of hexagonal microfluidic devices and cell-based reporter cells allows detection of cytokine-producing cells at the single-cell level
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Briones, Jonathan C., Okui, Yuga, Espulgar, Wilfred V., Park, JeongHoon, Itotagawa, Eri, Koyama, Shohei, Tamiya, Eiichi, Takamatsu, Hyota, and Saito, Masato
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- 2023
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6. Multiband elastic wave energy localization for highly amplified piezoelectric energy harvesting using trampoline metamaterials
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Lee, Geon, Park, Jeonghoon, Choi, Wonjae, Ji, Bonggyu, Kim, Miso, and Rho, Junsuk
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- 2023
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7. Elastic bound states in the continuum by acoustoelastic interaction
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Lee, Dongwoo, Park, Jeonghoon, Kim, Seokwoo, Mun, Jungho, Kim, Jaekyung, Piao, Xianji, Park, Namkyoo, and Rho, Junsuk
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- 2023
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8. Chiral trabeated metabeam for low-frequency multimode wave mitigation via dual-bandgap mechanism
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Park, Jeonghoon, Lee, Dongwoo, Jang, Yeongtae, Lee, Anna, and Rho, Junsuk
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- 2022
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9. Tunable metasurfaces via the humidity responsive swelling of single-step imprinted polyvinyl alcohol nanostructures
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Ko, Byoungsu, Badloe, Trevon, Yang, Younghwan, Park, Jeonghoon, Kim, Jaekyung, Jeong, Heonyeong, Jung, Chunghwan, and Rho, Junsuk
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- 2022
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10. All‐Polarized Elastic Wave Attenuation and Harvesting via Chiral Mechanical Metamaterials.
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Park, Jeonghoon, Lee, Geon, Kwon, Hyunhee, Kim, Miso, and Rho, Junsuk
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ELASTIC waves , *ENERGY harvesting , *MECHANICAL energy , *NUMERICAL analysis , *METAMATERIALS - Abstract
Manipulating elastic waves of all polarizations is highly challenging due to the complex behavior of elastic waves. To achieve simultaneous broadband vibration attenuation and energy harvesting across all polarizations of elastic waves at low‐frequency ranges, a chiral mechanical metamaterial‐based energy harvester is proposed in this study. The systematic development of a complete bandgap and defect structure is achieved through theoretical eigenfrequency analysis and numerical simulations. The defect structure is incorporated to induce defect modes for all wave polarizations within the complete bandgap region, ensuring their compatibility with the overall shape of the structure. The proposed chiral mechanical metamaterial with defect (CMMD) demonstrated significant performance improvements, achieving electrical output power enhancements that are 20.5 times for flexural waves and 511.4 times for longitudinal‐torsional waves compared to the defectless chiral mechanical metamaterial. This study accentuates the thoughtful design and multifaceted utility of chiral mechanical metamaterials, paving the way for their application not only in energy harvesting but also in wave attenuation for various polarizations. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Investigating Static and Dynamic Behaviors in 3D Chiral Mechanical Metamaterials by Disentangled Generative Models.
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Park, Jeonghoon, Noh, Jaebum, Shin, Jehyeon, Gu, Grace X., and Rho, Junsuk
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GENERATIVE adversarial networks , *STRESS concentration , *COMPRESSION loads , *DEEP learning , *METAMATERIALS - Abstract
Chiral mechanical metamaterials with engineered asymmetric structures have garnered significant interest owing to their potential for manipulating mechanical waves and unconventional mechanical properties. Although several design methodologies have made significant strides in the design and discovery of chiral mechanical metamaterials, 3D designs that incorporate multiple mechanical characteristics remain largely unexplored and the static and dynamic properties of these structures have not received sufficient attention. Here, an innovative approach is introduced for the inverse design of 3D chiral mechanical metamaterials with desired static and dynamic properties, leveraging streamlined shapes to enable a versatile design. By employing conditional generative adversarial networks (c‐GANs), the desired mechanical properties are targeted by focusing on both wave attenuation and stress distribution under compression and shear loading. 3D chiral mechanical metamaterials with additive manufacturing are fabricated to demonstrate the performance of the proposed c‐GAN. Experimental investigations show that the generated structures exhibited a wide range of wave attenuation properties, low stress concentrations, and a variety of stress‐strain curve profiles including nonlinear stiffness, demonstrating their effectiveness in achieving the desired mechanical characteristics. This research offers significant advancements in the on‐demand design capabilities of metamaterials and their applications. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Quantum linear system algorithm applied to communication systems
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Park, Jeonghoon and Heo, Jun
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- 2022
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13. Sleep-disordered breathing and wake-up stroke: a differential association depending on etiologic subtypes
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Park, Jeonghoon, Yeo, Minju, Kim, Jinsu, Kim, Seongheon, Lee, Seung-Hwan, Kwon, Sungok, Shin, Dong-Ick, Lee, Sangkil, and Lee, Seo-Young
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- 2020
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14. The lysosomal Ragulator complex plays an essential role in leukocyte trafficking by activating myosin II
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Nakatani, Takeshi, Tsujimoto, Kohei, Park, JeongHoon, Jo, Tatsunori, Kimura, Tetsuya, Hayama, Yoshitomo, Konaka, Hachiro, Morita, Takayoshi, Kato, Yasuhiro, Nishide, Masayuki, Koyama, Shyohei, Nada, Shigeyuki, Okada, Masato, Takamatsu, Hyota, and Kumanogoh, Atsushi
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- 2021
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15. VideoSet: A large-scale compressed video quality dataset based on JND measurement
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Wang, Haiqiang, Katsavounidis, Ioannis, Zhou, Jiantong, Park, Jeonghoon, Lei, Shawmin, Zhou, Xin, Pun, Man-On, Jin, Xin, Wang, Ronggang, Wang, Xu, Zhang, Yun, Huang, Jiwu, Kwong, Sam, and Kuo, C.-C. Jay
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- 2017
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16. Spontaneous resolution of inflammatory myopathy involving the masseter muscle following COVID-19 mRNA vaccination.
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Tada, Tomomi, Murao, Haruka, Shiratani, Reo, Park, JeongHoon, Hideshima, Makoto, Kanki, Hideaki, Ishikawa, Nachi, Shibahara, Takayuki, Fujimoto, Jun, and Higa, Shinji
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DERMATOMYOSITIS ,MASSETER muscle ,MYOSITIS ,COVID-19 vaccines ,SARS-CoV-2 ,MUSCLE diseases - Published
- 2024
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17. Two-dimensional in vivo rectal dosimetry using an endorectal balloon with unfoldable radiochromic film during prostate cancer radiotherapy
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Jeang, Eun Hee, Min, Soonki, Cho, Kwan Ho, Hwang, Ui-Jung, Choi, Sang Hyoun, Kwak, Jungwon, Jeong, Jong Hwi, Kim, Haksoo, Lee, Se Byeong, Shin, Dongho, Park, Jeonghoon, Kim, Joo-Young, Kim, Dae Yong, and Lim, Young Kyung
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- 2016
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18. Secretion of mitochondrial DNA via exosomes promotes inflammation in Behçet's syndrome.
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Konaka, Hachiro, Kato, Yasuhiro, Hirano, Toru, Tsujimoto, Kohei, Park, JeongHoon, Koba, Taro, Aoki, Wataru, Matsuzaki, Yusei, Taki, Masayasu, Koyama, Shohei, Itotagawa, Eri, Jo, Tatsunori, Hirayama, Takehiro, Kawai, Taro, Ishii, Ken J, Ueda, Mitsuyoshi, Yamaguchi, Shigehiro, Akira, Shizuo, Morita, Takayoshi, and Maeda, Yuichi
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BEHCET'S disease ,MITOCHONDRIAL DNA ,EXOSOMES ,SECRETION ,EXTRACELLULAR space ,INFLAMMATION - Abstract
Mitochondrial DNA (mtDNA) leakage into the cytoplasm can occur when cells are exposed to noxious stimuli. Specific sensors recognize cytoplasmic mtDNA to promote cytokine production. Cytoplasmic mtDNA can also be secreted extracellularly, leading to sterile inflammation. However, the mode of secretion of mtDNA out of cells upon noxious stimuli and its relevance to human disease remain unclear. Here, we show that pyroptotic cells secrete mtDNA encapsulated within exosomes. Activation of caspase‐1 leads to mtDNA leakage from the mitochondria into the cytoplasm via gasdermin‐D. Caspase‐1 also induces intraluminal membrane vesicle formation, allowing for cellular mtDNA to be taken up and secreted as exosomes. Encapsulation of mtDNA within exosomes promotes a strong inflammatory response that is ameliorated upon exosome biosynthesis inhibition in vivo. We further show that monocytes derived from patients with Behçet's syndrome (BS), a chronic systemic inflammatory disorder, show enhanced caspase‐1 activation, leading to exosome‐mediated mtDNA secretion and similar inflammation pathology as seen in BS patients. Collectively, our findings support that mtDNA‐containing exosomes promote inflammation, providing new insights into the propagation and exacerbation of inflammation in human inflammatory diseases. Synopsis: Mitochondrial DNA (mtDNA) secreted by pyroptotic cells is encapsulated within exosomes and induces excessive inflammation resembling symptoms seen in patients with Behçet's syndrome. In pyroptotic cells, the activation of caspase‐1 and subsequent action of gasdermin‐D promote the efflux of mtDNA from the mitochondria into the cytoplasm.Activation of caspase‐1 promotes the formation of intracellular vesicles (ILVs), mtDNA uptake into ILVs, and its release into the extracellular space via exosomes.The encapsulation of mtDNA within exosomes promotes inflammation, leukocyte mobilization, and cytokine production.Patients with Behçet's syndrome show increased mtDNA in the blood and caspase‐1‐mediated mitochondrial damage in the isolated monocytes.In patients with Behçet's syndrome monocytes secrete mtDNA‐containing exosomes that induce pathological inflammation in an NLRP3‐ and TLR9‐dependent manner. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Underwater stealth metasurfaces composed of split-orifice–conduit hybrid resonators.
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Lee, Dongwoo, Jang, Yeongtae, Park, Jeonghoon, Kang, In Seok, Li, Jensen, and Rho, Junsuk
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SONAR ,RESONATORS ,SPEED of sound ,TRANSFER matrix ,ABSORPTION spectra ,HELMHOLTZ resonators ,ORIFICE plates (Fluid dynamics) - Abstract
The development of sound-absorbing materials for noise reduction in daily life has been a prolonged issue that also applies to a recognized need for submarine anechoic tiles to stay independent from SONAR (SOund NAvigation Ranging). Here, we present an underwater stealth metasurface that uses split-orifice–conduit (SOC) hybrid resonators to significantly reduce its acoustic reflectance. A theoretical analysis of SOC elements provides an approach to quantifying acoustic characteristics using the transfer matrix method in a single metasurface. The findings confirm that we can tune the absorption with respect to a resonating frequency by adjusting geometrical parameters. Utilizing a hybrid mechanism that enables easy access to coupled resonances, we obtain broadband absorption spectra even in the presence of a covariant sound speed profile in the deep sea and a thermoviscous effect on unit cells of the metasurface. Such a metasurface will provide a further step toward developing feasible underwater stealth technologies for submarines and remains to be experimentally demonstrated. [ABSTRACT FROM AUTHOR]
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- 2021
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20. A comparison of the quality assurance of four dosimetric tools for intensity modulated radiation therapy
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Son Jaeman, Baek Taesung, Lee Boram, Shin Dongho, Park Sung Yong, Park Jeonghoon, Lim Young Kyung, Lee Se Byeong, Kim Jooyoung, and Yoon Myonggeun
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intensity modulated radiation therapy ,quality assurance ,dosimetric tool ,gamma index ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Background. This study was designed to compare the quality assurance (QA) results of four dosimetric tools used for intensity modulated radiation therapy (IMRT) and to suggest universal criteria for the passing rate in QA, irrespective of the dosimetric tool used.
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- 2015
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21. Achromatic elastic metalens for high-performance confocal piezoelectric energy harvesting.
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Lee, Geon, Park, Jeonghoon, Choi, Wonjae, Ji, Bonggyu, Kim, Miso, and Rho, Junsuk
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ENERGY harvesting , *STRUCTURAL health monitoring , *WAVE energy , *STRAIN energy , *CONFORMAL mapping - Abstract
In this study, we analytically, numerically, and experimentally investigated a high-performance confocal piezoelectric energy harvesting system. We achieved a significantly enhanced electrical performance through a Mikaelian lens, which achromatically focuses ambient elastic waves, resulting in the formation of a highly amplified strain energy field in the piezoelectric energy harvester. Previous studies on piezoelectric energy harvesting platforms have limitations, such as the focal position changing with operating frequencies and impedance mismatching owing to inclusions or holes. To address these problems, we utilized the self-focusing ability based on the conformal mapping theory and achromatic ability based on the Kirchhoff–Love thin plate theory to design our Mikaelian lens-based piezoelectric energy harvesting platform. The proposed platform demonstrates a remarkable elastic wave focusing ability at an identical focal position for a broad frequency range. The experimentally visualized wave fields matched well with the numerically calculated full-wave harmonic simulation results. We achieved highly amplified output power up to 1.44 mW within a broad range from 40 to 60 kHz out of the same focal point owing to confined elastic wave energy; the output power extracted at this confocal position was up to 3.76 times higher than that extracted at the lens start position. Our highly performance and broadband achromatic piezoelectric energy harvesting platform lays an attractive foundation for designing potential applications, such as wireless sensing, structural health monitoring, and biomedical devices. [ABSTRACT FROM AUTHOR]
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- 2023
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22. Technical note: Energy dependence of the Gafchromic EBT4 film: Dose‐response curves for 70 kV, 6 MV, 6 MV FFF, 10 MV FFF, and 15 MV x‐ray beams.
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Chan, Maria F., Park, Jeonghoon, Aydin, Resat, and Lim, Seng‐Boh
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X-rays , *PHOTON beams , *SPATIAL resolution , *FILMSTRIPS , *MEDICAL dosimetry , *SIGNAL-to-noise ratio , *RADIOTHERAPY safety - Abstract
Background: EBT4 was newly released for radiotherapy quality assurance to improve the signal‐to‐noise ratio in radiochromic film dosimetry. It is important to know its dose‐response characteristics before its use in the clinic. Purpose: This study aims to investigate and compare the dose‐response curves of the Gafchromic EBT4 film for megavoltage and kilovoltage x‐ray beams with different dose levels, scanning spatial resolutions, and sizes of region of interest (ROI). Methods: EBT4 film (Lot#07052201) calibration strips (3.5 × 20 cm2) were exposed to a 10×10 cm2 open field at doses of 0, 63, 125, 500, 750, 1000 cGy using 6 MV photon beam. EBT4 film strips from the same lot were then exposed to each x‐ray beam (6 MV, 6 MV FFF, 10 MV FFF, 15 MV, and 70 kV) at six dose values (50, 100, 300, 600, 800, 1000 cGy). A full sheet (25 × 20 cm2) of EBT4 film was irradiated at each energy with 300 cGy for profile comparison with the treatment planning calculation. At two different spatial resolutions of 72 and 300 dpi, each film piece was scanned three consecutive times in the center of an Epson 10000XL flatbed scanner in 48‐bit color. The scanned images were analyzed using FilmQA Pro. For each scanned image, an ROI of 2 × 2 cm2 at the field center was selected to obtain the average pixel value with its standard deviation in the ROI. An additional ROI of 1 cm diameter circle was also used to evaluate the impact of ROI shape and size, especially for FFF beams. The dose value, average dose‐response value, and associated uncertainty were determined for each energy and relative responses were analyzed. The Student's t‐test was performed to evaluate the statistical significance of the dose‐response values with different color channels, ROI shapes, and spatial resolutions. Results: The dose‐response curves for the five x‐ray energies were compared in three color channels. Weak energy dependence was found among the megavoltage beams. No significant differences (average ∼1.1%) were observed for all doses in this study among 6 MV, 6 MV FFF, 10 MV FFF, and 15 MV beams, regardless of spatial resolution and color channel. However, a statistically significant difference in dose‐response was observed up to 12% between 70 kV and 6 MV beams. Conclusions: The dose‐response curves for Gafchromic EBT4 films were nearly independent of the energy of the photon beams among 6 MV, 6 MV FFF, 10 MV FFF, and 15 MV. For very low‐energy photons (e.g., 70 kV), a separate calibration from the same low‐energy x‐ray is necessary. [ABSTRACT FROM AUTHOR]
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- 2023
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23. SLE stratification based on BAFF and IFN-I bioactivity for biologics and implications of BAFF produced by glomeruli in lupus nephritis.
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Itotagawa, Eri, Tomofuji, Yoshihiko, Kato, Yasuhiro, Konaka, Hachiro, Tsujimoto, Kohei, Park, JeongHoon, Nagira, Daiki, Hirayama, Takehiro, Jo, Tatsunori, Hirano, Toru, Morita, Takayoshi, Nishide, Masayuki, Nishida, Sumiyuki, Shima, Yoshihito, Narazaki, Masashi, Okada, Yukinori, Takamatsu, Hyota, and Kumanogoh, Atsushi
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BIOLOGICAL products ,LUPUS nephritis ,SYSTEMIC lupus erythematosus - Abstract
Objective B-cell activating factor (BAFF) is implicated in SLE pathogenesis. Blocking BAFF signalling has contributed to reducing glucocorticoid dosage and preventing organ damage. However, clinical characteristics of patients who may benefit from this therapy are not yet fully elucidated. Therefore, we identified patients with high BAFF-bioactivity to investigate their clinical characteristics and BAFF-producing cells. Methods We established the reporter cell for BAFF and investigated the clinical characteristics of SLE patients with high BAFF-bioactivity. We identified BAFF-expressing kidney cells using publicly available scRNA-seq data and immunohistological analysis. SLE patients were stratified based on the bioactivity of BAFF and type-I IFN (IFN-I) to identify associated characteristic clinical manifestations. Results SLE patients, especially patients with LN, had significantly higher serum BAFF-bioactivity than healthy controls (HC) and non-LN patients. Additionally, single-cell-RNA-seq data and immunohistological analysis of kidney samples from LN patients revealed that BAFF is expressed in glomerular macrophages and mesangial cells. Notably, BAFF bioactivity was elevated in the urine of LN patients compared with that of non-LN patients, while no IFN-I bioactivity was detected in the urine. Furthermore, SLE stratification based on bioactivities of serum BAFF and IFN-I revealed the clinical characteristics of patients: high BAFF represented patients with LN and high IFN-I represented patients with blood and skin manifestations. Conclusions Monitoring urinary BAFF-bioactivity may be valuable in diagnosing LN. Furthermore, stratification based on serum BAFF and IFN-I bioactivities may allow the identification of appropriate patients for biologics targeting BAFF and IFN-I. [ABSTRACT FROM AUTHOR]
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- 2023
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24. Humidity‐Responsive RGB‐Pixels via Swelling of 3D Nanoimprinted Polyvinyl Alcohol.
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Ko, Byoungsu, Kim, Jaekyung, Yang, Younghwan, Badloe, Trevon, Park, Jeonghoon, Ko, Joo Hwan, Jeong, Minsu, Kang, Hyunjung, Jung, Chunghwan, Song, Young Min, and Rho, Junsuk
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SILVER nanoparticles ,FOOD storage ,COLOR printing ,HUMIDITY ,INTELLIGENT sensors ,POLYVINYL alcohol ,IMPRINTED polymers - Abstract
Humidity‐responsive structural coloration is actively investigated to realize real‐time humidity sensors for applications in smart farming, food storage, and healthcare management. Here, humidity‐tunable nano pixels are investigated with a 700 nm resolution that demonstrates full standard RGB (sRGB) gamut coverage with a millisecond‐response time. The color pixels are designed as Fabry–Pérot (F–P) etalons which consist of an aluminum mirror substrate, humidity‐responsive polyvinyl alcohol (PVA) spacer, and a top layer of disordered silver nanoparticles (NPs). The measured volume change of the PVA reaches up to 62.5% when the relative humidity (RH) is manipulated from 20 to 90%. The disordered silver NP layer permits the penetration of water molecules into the PVA layer, enhancing the speed of absorption and swelling down to the millisecond level. Based on the real‐time response of the hydrogel‐based F–P etalons with a high‐throughput 3D nanoimprint technique, a high‐resolution multicolored color print that can have potential applications in display technologies and optical encryption, is demonstrated. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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25. Separable States to Distribute Entanglement
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Park, Jeonghoon and Lee, Soojoon
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- 2012
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26. ROAD+: Route Optimization with Additional Destination-Information and Its Mobility Management in Mobile Networks
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Kim, Moonseong, Mutka, Matt W., Park, Jeonghoon, and Choo, Hyunseung
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- 2010
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27. Thyroid Dysfunction and the Effect of Iodine-Deficient Parenteral Nutrition in Very Low Birth Weight Infants: A Nationwide Analysis of a Korean Neonatal Network Database.
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Cho, JaeYoung, Park, JeongHoon, Yeom, JungSook, Jun, JinSu, Park, JiSook, Park, EunSil, Seo, Ji-Hyun, Lim, JaeYoung, Park, Chan-Hoo, and Woo, Hyang-Ok
- Abstract
Background: To investigate the impact of nutritional iodine deficiency on thyroid dysfunction (TD) in very low birth weight (VLBW) infants, we analyzed the association between iodine-deficient parenteral nutrition (PN) and TD requiring L-thyroxine (TD-LT4). Methods: Data of VLBW infants were obtained from the Korean Neonatal Network registry. Factors including duration of PN were analyzed according to TD-LT4. Results: TD-LT4 occurred in 490 (8.7%) of 5635 infants, and more frequently occurred in infants requiring PN for ≥4 weeks (10.2%). PN ≥ 4 weeks was one of the risk factors for TD-LT4, with an odds ratio (OR) of 1.346, p = 0.002. However, multivariate analysis showed that TD-LT4 was more of a risk for infants that were small for gestational age (OR 2.987, p < 0.001) and for other neonatal morbidities such as seizures (OR 1.787, p = 0.002) and persistent pulmonary hypertension (OR 1.501, p = 0.039) than PN ≥ 4 weeks (OR 0.791, p = 0.080). Conclusions: Prolonged iodine-deficient PN might affect TD-LT4 in VLBW infants. However, the effect of nutritional iodine deficiency on TD-LT4 risk was less than that of SGA or severe neonatal morbidities in Korean VLBW infants. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. Therapeutic Response Monitoring with 89 Zr-DFO-Pertuzumab in HER2-Positive and Trastuzumab-Resistant Breast Cancer Models.
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Kang, Minwoo, Shin, Jong Il, Han, Sangjin, Kim, Jung Young, Park, Jeonghoon, Kim, Kwang Il, Kang, Joo Hyun, and Lee, Tae Sup
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HER2 positive breast cancer ,HEAT shock proteins ,TRASTUZUMAB ,WESTERN immunoblotting ,POSITRON emission tomography - Abstract
Immuno-positron emission tomography (PET) has great potential to evaluate the target expression level and therapeutic response for targeted cancer therapy. Immuno-PET imaging with pertuzumab, due to specific recognition in different binding sites of HER2, could be useful for the determination of the therapeutic efficacy of HER2-targeted therapy, trastuzumab, and heat shock protein 90 (HSP90) inhibitor, in HER2-expressing breast cancer. The aim of this study is to evaluate the feasibility of monitoring therapeutic response with
89 Zr-DFO-pertuzumab for the treatment of HER2-targeted therapeutics, trastuzumab, or the HSP90 inhibitor 17-DMAG, in trastuzumab-resistant JIMT-1 breast cancer models. We prepared an immuno-PET imaging agent using desferoxamine (DFO)-pertuzumab labeled with89 Zr and performed the biodistribution and PET imaging in breast cancer xenograft models for monitoring therapeutic response to HER2-targeted therapy.89 Zr-DFO-pertuzumab was successfully prepared and showed specific binding to HER2 in vitro and clearly visualized HER2 expressing JIMT-1 tumors.89 Zr-DFO-pertuzumab had prominent tumor uptake in HER2 expressing JIMT-1 tumors. JIMT-1 tumors showed trastuzumab-resistant and HSP90 inhibitor sensitive characterization. In immuno-PET imaging, isotype antibody-treated JIMT-1 tumors had similar uptake in trastuzumab-treated JIMT-1 tumors, but 17-DMAG-treated JIMT-1 tumors showed greatly reduced uptake compared to vehicle-treated tumors. Additionally, HER2 downregulation evaluated by immuno-PET imaging was verified by western blot analysis and immunofluorescence staining which resulted in a significant reduction in the tumor's HER2 level in 17-DMAG-treated JIMT-1 tumors.89 Zr-DFO-pertuzumab immuno-PET may be clinically translated to select pertinent patients for HER2-targeted therapy and to monitor the therapeutic response in HER2-positive cancer patients under various HER2-targeted therapeutics treatments. [ABSTRACT FROM AUTHOR]- Published
- 2022
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29. Piezoelectric energy harvesting using mechanical metamaterials and phononic crystals.
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Lee, Geon, Lee, Dongwoo, Park, Jeonghoon, Jang, Yeongtae, Kim, Miso, and Rho, Junsuk
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ENERGY consumption ,METAMATERIALS ,WAVE energy ,ELECTRICAL energy ,MECHANICAL energy ,PHONONIC crystals ,ENERGY harvesting - Abstract
Mechanical metamaterials and phononic crystals enable localizing, focusing, and guiding of elastic or acoustic waves in various ways. Here, we describe the physical mechanisms underpinning wave manipulation and then review the most recent energy harvesting methods for converting localized mechanical wave energy to useable electrical energy. Due to the exceptional wave-matter interactions enabled by the man-made structures, energy is collected more efficiently than through conventional methods. Artificially designed mechanical structures are versatile, especially when used in renewable and ecologically-benign energy transformation, and have a wide array of potential applications. Judicious design of metamaterials and phononic crystals permits the realization of novel localization and wave-guiding properties. Here, recent developments and strategies for applying these structures to piezoelectric energy harvesting are reviewed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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30. Double-Focusing Gradient-Index Lens with Elastic Bragg Mirror for Highly Efficient Energy Harvesting.
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Park, Jeonghoon, Lee, Geon, Lee, Dongwoo, Kim, Miso, and Rho, Junsuk
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ENERGY harvesting , *ELASTIC waves , *RENEWABLE energy sources , *PHONONIC crystals , *MIRRORS , *LOCALIZATION (Mathematics) , *HARVESTING time - Abstract
The applicability of piezoelectric energy harvesting is increasingly investigated in the field of renewable energy. In improving harvester efficiency, manipulating elastic waves through a geometric configuration as well as upgrading harvester elements is important. Periodic structures, such as phononic crystals and metamaterials, are extensively employed to control elastic waves and enhance harvesting performance, particularly in terms of wave localization and focusing. In this study, we propose a double-focusing flexural energy harvesting platform consisting of a gradient-index lens and elastic Bragg mirror. Based on the design process, the frequency and time response of the harvesting platform are analyzed. The results indicate that the output voltage and power calculated at 1800 Ω are 7.9 and 62 times higher than those observed in the bare plate, respectively. Even when compared to the existing gradient-index system, they are 1.5 and 2.3 times higher, respectively. These findings can facilitate the usage of periodic structures as geometric stimuli to significantly enhance harvesting performance. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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31. Is Halcyon feasible for single thoracic or lumbar vertebral segment SBRT?
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Li, Fang, Park, Jeonghoon, Lalonde, Ron, Jang, Si Young, diMayorca, Maria Stefania, Flickinger, John C., Keller, Andrew, and Huq, Mohammed Saiful
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CAUDA equina ,CONE beam computed tomography ,STEREOTACTIC radiotherapy ,VOLUMETRIC-modulated arc therapy ,SPINAL canal ,THORACIC vertebrae - Abstract
Purpose: Halcyon linear accelerators employ intensity‐modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) techniques. The Halcyon offers translational, but not rotational, couch correction, which only allows a 3 degrees of freedom (3‐DOF) correction. In contrast, the TrueBeam (TB) linear accelerator offers full 6‐DOF corrections. This study aims to evaluate the difference in treatment plan quality for single thoracic or lumbar vertebral segment SBRT between the Halcyon and TB linear accelerators. In addition, this study will also investigate the effect of patient rotational setup errors on the final plan quality. Methods: We analyzed 20 patients with a single‐level spine metastasis located between the T7 and L5 vertebrae near the spinal canal. The median planning target volume was 52.0 cm3 (17.9–138.7 cm3). The median tumor diameter in the axial plane was 4.6 cm (range 1.7–6.8 cm), in the sagittal plane was 3.3 cm (range 2–5 cm). The prescription doses were either 12–16 Gy in 1 fraction or 18–24 Gy in 3 fractions. All patients were treated on the TB linear accelerator with a 2.5 mm Multi‐Leaf Collimator (MLC) leaf width. Treatment plans were retrospectively created for the Halcyon, which has a 5 mm effective MLC leaf width. The 20 patients had a total of 50 treatments. Analysis of the 50 cone beam computed tomography (CBCT) scans showed average rotational setup errors of 0.6°, 1.2°, and 0.8° in pitch, yaw, and roll, respectively. Rotational error in roll was not considered in this study, as the original TB plans used a coplanar volumetric modulated arc therapy (VMAT) technique, and each 1° of roll will contribute an error of 1/360. If a plan has 3 arcs, the contribution from errors in roll will be < 0.1%. To simulate different patient setup errors, for each patient, 12 CT image datasets were generated in Velocity AI with different rotational combinations at a pitch and yaw of 1°, 2°, and 3°, respectively. We recalculated both the TB and Halcyon plans on these rotated images. The dosimetric plan quality was evaluated based on the percent tumor coverage, the Conformity Index (CI), Gradient Index (GI), Homogeneity index (HI), the maximum dose to the cord/cauda, and the volume of the cord/cauda receiving 8, 10, and 12 Gy (V8Gy, V10Gy and V12Gy). Paired t‐tests were performed between the original and rotated plans with a significance level of 0.05. Results: The Eclipse based VMAT plans on Halcyon achieved a similar target coverage (92.3 ± 3.0% vs. 92.4 ± 3.3%, p = 0.82) and CI (1.0 ± 0.1 vs. 1.1 ± 0.2, p = 0.12) compared to the TB plans. The Gradient index of Halcyon is higher (3.96 ±0.8) than TB (3.85 ±0.7), but not statistically significant. The maximum dose to the spinal cord/cauda was comparable (11.1 ± 2.8 Gy vs. 11.4 ± 3.6 Gy, p = 0.39), as were the V8Gy, V10Gy and V12Gy to the cord/cauda. The dosimetric influence of patient rotational setup error was statistically insignificant for rotations of up to 1° pitch/yaw (with similar target coverage, CI, max cord/cauda dose and V8Gy, V10Gy, V12Gy for cord/cauda). The total number of monitor units (MUs) for Halcyon (4998 ± 1688) was comparable to that of TB (5463 ± 2155) (p = 0.09). Conclusions: The Halcyon VMAT plans for a single thoracic or lumbar spine metastasis were dosimetrically comparable to the TB plans. Patient rotation within 1° in the pitch and yaw directions, if corrected by translation, resulted in insignificant dosimetric effects. The Halcyon linear accelerator is an acceptable alternative to TB for the treatment of single thoracic or lumbar spinal level metastasis, but users need to be cautious about the patient rotational setup error. It is advisable to select patients appropriately, including only those with the thoracic or lumbar spine involvement and keeping at least 2 mm separation between the target and the cord/cauda. More margin is needed if the distance between the isocenter and cord/cauda is larger. It is advisable to place the planning isocenter close to the spinal canal to further mitigate the rotational error. Summary: We simulated various scenarios of patient setup errors with different rotational combinations of pitch and yaw with 1°, 2°, and 3°, respectively. Rotation was corrected with translation only to mimic the Halcyon treatment scenario. Using the Halcyon for treating a tumor in a single thoracic or lumbar vertebral segment is feasible, but caution should be noted in patients requiring rotational corrections of > 1° in the absence of 6‐DOF correction capabilities. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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32. Inducing and Probing Localized Excitons in Atomically Thin Semiconductors via Tip‐Enhanced Cavity‐Spectroscopy.
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Lee, Hyeongwoo, Kim, Inki, Park, Chulho, Kang, Mingu, Choi, Jinseong, Jeong, Kwang‐Yong, Mun, Jungho, Kim, Yeseul, Park, Jeonghoon, Raschke, Markus B., Park, Hong‐Gyu, Jeong, Mun Seok, Rho, Junsuk, and Park, Kyoung‐Duck
- Subjects
EXCITON theory ,SEMICONDUCTORS ,LIGHT sources ,BOW-tie antennas ,CRYSTAL defects - Abstract
In atomically thin semiconductors, localized exciton (XL) coupled to light provides a new class of optical sources for potential applications in quantum communication. However, in most studies, XL photoluminescence (PL) from crystal defects has mainly been observed in cryogenic conditions because of their sub‐wavelength emission region and low quantum yield at room temperature. Hybrid‐modality of cavity‐spectroscopy to induce and probe the XL emissions at the nanoscale in atomically thin semiconductors is presented. By placing a WSe2 monolayer on the two extremely sharp Au tips in a bowtie antenna with a radius of curvature of <1 nm, tensile strain of ≈0.3% is effectively induced in a <30 nm region to create robust XL states. The Au tip then approaches the strained crystal region to enhance the XL emissions and probe them with tip‐enhanced photoluminescence (TEPL) spectroscopy at room temperature. Through this triple‐sharp‐tips cavity‐spectroscopy with <15 nm spatial resolution, TEPL enhancement as high as ≈4.0 × 104 by the Purcell effect is achieved, and peak energy shifts of XL up to ≈40 meV are observed. This approach combining nano‐cavity and ‐spectroscopy provides a systematic way to induce and probe the radiative emission of localized excitons in 2D semiconductors offering new strategies for dynamic quantum nano‐optical devices. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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33. Prediction of conical collimator collision for stereotactic radiosurgery.
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Park, Jeonghoon, McDermott, Ryan, Kim, Sangroh, and Huq, M. Saiful
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STEREOTACTIC radiosurgery ,FORECASTING ,COLLIMATORS ,PHYSICAL measurements ,SYSTEMS software ,EYE tracking - Abstract
The purpose of this study is to predict the collision clearance distance of stereotactic cones with treatment setup devices in cone‐based stereotactic radiosurgery (SRS). The BrainLAB radiosurgery system with a Frameless Radiosurgery Positioning Array and dedicated couch top was targeted in this study. The positioning array and couch top were scanned with CT simulators, and their outer contours of were detected. The minimum clearance distance was estimated by calculating the Euclidian distances between the surface of the SRS cones and the nearest surface of the outer contours. The coordinate transformation of the outer contour was performed by incorporating the Beam's Eye View at a planned arc range and couch angle. From the minimum clearance distance, the collision‐free gantry ranges for each couch angle were sequentially determined. An in‐house software was developed to calculate the clearance distance between the cone surface and the outer contours, and thus determine the occurrence of a collision. The software was extensively tested for various combinations of couch and arc angles at multiple isocenter locations for two combinations of cone‐couch systems. A total of 50 arcs were used to validate the calculation accuracies of the software for each system. The calculated minimum distances and collision‐free angles from the software were verified by physical measurements. The calculated minimum distances were found to agree with the measurements to within 0.3 ± 0.9 mm. The collision‐free arc angles from the software also agreed with the measurements to within 1.1 ± 1.1° with a 5‐mm safety margin for 20 arcs. In conclusion, the in‐house software was able to calculate the minimum clearance distance with <1.0 mm accuracy and to determine the collision‐free arc range for the cone‐based BrainLab SRS system. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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34. Apoptosis-derived membrane vesicles drive the cGAS-STING pathway and enhance type I IFN production in systemic lupus erythematosus.
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Yasuhiro Kato, JeongHoon Park, Hyota Takamatsu, Hachirou Konaka, Wataru Aoki, Syunsuke Aburaya, Mitsuyoshi Ueda, Masayuki Nishide, Shohei Koyama, Yoshitomo Hayama, Yuhei Kinehara, Toru Hirano, Yoshihito Shima, Masashi Narazaki, Atsushi Kumanogoh, Kato, Yasuhiro, Park, JeongHoon, Takamatsu, Hyota, Konaka, Hachirou, and Aoki, Wataru
- Abstract
Objective: Despite the importance of type I interferon (IFN-I) in systemic lupus erythematosus (SLE) pathogenesis, the mechanisms of IFN-I production have not been fully elucidated. Recognition of nucleic acids by DNA sensors induces IFN-I and interferon-stimulated genes (ISGs), but the involvement of cyclic guanosine monophosphate (GMP)-AMP synthase (cGAS) and stimulator of interferon genes (STING) in SLE remains unclear. We studied the role of the cGAS-STING pathway in the IFN-I-producing cascade driven by SLE serum.Methods: We collected sera from patients with SLE (n=64), patients with other autoimmune diseases (n=31) and healthy controls (n=35), and assayed them using a cell-based reporter system that enables highly sensitive detection of IFN-I and ISG-inducing activity. We used Toll-like receptor-specific reporter cells and reporter cells harbouring knockouts of cGAS, STING and IFNAR2 to evaluate signalling pathway-dependent ISG induction.Results: IFN-I bioactivity and ISG-inducing activities of serum were higher in patients with SLE than in patients with other autoimmune diseases or healthy controls. ISG-inducing activity of SLE sera was significantly reduced in STING-knockout reporter cells, and STING-dependent ISG-inducing activity correlated with disease activity. Double-stranded DNA levels were elevated in SLE. Apoptosis-derived membrane vesicles (AdMVs) from SLE sera had high ISG-inducing activity, which was diminished in cGAS-knockout or STING-knockout reporter cells.Conclusions: AdMVs in SLE serum induce IFN-I production through activation of the cGAS-STING pathway. Thus, blockade of the cGAS-STING axis represents a promising therapeutic target for SLE. Moreover, our cell-based reporter system may be useful for stratifying patients with SLE with high ISG-inducing activity. [ABSTRACT FROM AUTHOR]- Published
- 2018
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35. Predictive coding of CU quadtree structure for HEVC quality scalability.
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Won, Kwanghyun, Lee, Hoyoung, Park, Jeonghoon, and Jeon, Byeungwoo
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- 2013
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36. Inter-layer filtering for scalable extension of HEVC.
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Alshina, Elena, Alshin, Alexander, Cho, Yongjin, Park, JeongHoon, Pu, Wei, Chen, Jianle, Li, Xiang, Seregin, Vadim, and Karczewicz, Marta
- Published
- 2013
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37. High precision probability estimation for CABAC.
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Alshin, Alexander, Alshina, Elena, and Park, JeongHoon
- Abstract
Entropy coding is the main important part of all advanced video compression schemes. Context-adaptive binary arithmetic coding (CABAC) is entropy coding used in H.264/MPEG-4 AVC and H.265/HEVC standards. Probability estimation is the key factor of CABAC performance efficiency. In this paper high accuracy probability estimation for CABAC is presented. This technique is based on multiple estimations using different models. Proposed method was efficiently realized in integer arithmetic. High precision probability estimation for CABAC provides up-to 1,4% BD-rate gain. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
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38. Coding efficiency improvement of HEVC using asymmetric motion partitioning.
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Kim, Il-Koo, Lee, Sunil, Cheon, Min-Su, Lee, Tammy, and Park, JeongHoon
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In this paper, coding efficiency improvement of HEVC using asymmetric motion partitioning (AMP) is provided based on HM-6.0. AMP allows asymmetric shape partition mode of prediction unit (PU) for inter prediction. AMP improves the coding efficiency, since irregular image patterns, which otherwise would be constrained to being represented by a smaller symmetric partition, can now be more efficiently represented without requiring further splitting. For encoder speed up, additional conditions are checked before doing motion estimation for each motion partitions. If the certain conditions are met, additional motion estimation, which is main source of encoder complexity for AMP, can be skipped. Experimental results demonstrate that AMP with encoding speed-up shows 0.8% coding efficiency improvement with 14% encoding time increase. Especially for videoconference sequences, coding efficiency improvement reaches to 1.4%. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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39. Proton beam therapy reduces the incidence of acute haematological and gastrointestinal toxicities associated with craniospinal irradiation in pediatric brain tumors.
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Song, Sanghyuk, Park, Hyeon Jin, Yoon, Jong Hyung, Kim, Dae Woong, Park, Jeonghoon, Shin, Dongho, Shin, Sang Hoon, Kang, Hyoung Jin, Kim, Seung-Ki, Phi, Ji Hoon, and Kim, Joo-Young
- Subjects
BLOOD diseases ,GASTROINTESTINAL disease prevention ,BRAIN tumors ,CHI-squared test ,DRUG toxicity ,FISHER exact test ,LONGITUDINAL method ,PEDIATRICS ,RADIOTHERAPY ,RESEARCH funding ,STATISTICS ,T-test (Statistics) ,DATA analysis ,RETROSPECTIVE studies ,DATA analysis software ,DESCRIPTIVE statistics ,MANN Whitney U Test ,PREVENTION - Abstract
Background. The benefits of proton beam craniospinal irradiation (PrBCSI) in children have been extensively reported in dosimetric studies. However, there is limited clinical evidence supporting the use of PrBCSI. We compared the acute toxicity of PrBCSI relative to that of conventional photon beam CSI (PhBCSI) in children with brain tumours. Material and methods. We prospectively evaluated the haematological and gastrointestinal toxicities in 30 patients who underwent PrBCSI between April 2008 and December 2012. As a reference group, we retrospectively evaluated the medical records of 13 patients who underwent PhBCSI between April 2003 and April 2012. The median follow-up time from starting CSI was 22 months (range 2-118 months). The mean irradiation dose was 32.1 Gy (range 23.4-39.6 Gy) and 29.4 CGE (cobalt grey equivalents; range 19.8-39.6), in the PrBCSI and PhBCSI groups, respectively (p = 0.236). Results. There was no craniospinal fluid space relapse after curative therapy in either group of patients. Thrombocytopenia was less severe in the PrBCSI group than in the PhBCSI group (p = 0.012). The recovery rates of leukocyte and platelet counts measured one month after treatment were significantly greater in the PrBCSI group than in the PhBCSI group (p = 0.003 and p = 0.010, respectively). Diarrhoea was reported by 23% of patients in the PhBCSI group versus none in the PrBCSI group (p = 0.023). Conclusions. The incidence rates of thrombocytopenia and diarrhoea were lower in the PrBCSI group than in the PhBCSI group. One month after completing treatment, the recovery from leukopenia and thrombocytopenia was better in patients treated with PrBCSI than in those treated with PhBCSI. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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40. The volumetric change and dose-response relationship following hypofractionated proton therapy for chordomas.
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Kim, Yeon-Joo, Cho, Kwan Ho, Lim, Young Kyung, Park, Jeonghoon, Kim, Joo-Young, Shin, Kyung Hwan, Kim, Tae Hyun, Moon, Sung Ho, Lee, Sang Hyun, and Yoo, Heon
- Subjects
GERM cell tumors ,DOSE-response relationship (Radiation) ,MAGNETIC resonance imaging ,RADIATION doses ,RADIOTHERAPY ,SURVIVAL analysis (Biometry) ,DATA analysis software ,DESCRIPTIVE statistics ,KAPLAN-Meier estimator ,LOG-rank test - Abstract
A letter to the editor is presented in response to a article on topic related to the volumetric change and dose-response relationship after the hypofractionated proton therapy for chordomas.
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- 2014
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41. Block Partitioning Structure in the HEVC Standard.
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Kim, Il-Koo, Min, Junghye, Lee, Tammy, Han, Woo-Jin, and Park, JeongHoon
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PARALLEL algorithms ,STANDARDS ,VIDEO coding ,DATA structures ,INFORMATION processing ,COMPUTATIONAL complexity - Abstract
High Efficiency Video Coding (HEVC) is the latest joint standardization effort of ITU-T WP 3/16 and ISO/IEC JTC 1/SC 29/WG 11. The resultant standard will be published as twin text by ITU-T and ISO/IEC; in the latter case, it will also be known as MPEG-H Part 2. This paper describes the block partitioning structure of the draft HEVC standard and presents the results of an analysis of coding efficiency and complexity. Of the many new technical aspects of HEVC, the block partitioning structure has been identified as representing one of the most significant changes relative to previous video coding standards. In contrast to the fixed size 16\,\times\,16 macroblock structure of H.264/AVC, HEVC defines three different units according to their functionalities. The coding unit defines a region sharing the same prediction mode, e.g., intra and inter, and it is represented by the leaf node of a quadtree structure. The prediction unit defines a region sharing the same prediction information. The transform unit, specified by another quadtree, defines a region sharing the same transformation. This paper introduces technical details of the block partitioning structure of HEVC with an emphasis on the method of designing a consistent framework by combining the three different units together. Experimental results are provided to justify the role of each component of the block partitioning structure and a comparison with the H.264/AVC design is performed. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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42. Response to: 'Blood plasma versus serum: which is right for sampling circulating membrane microvesicles in human subjects?' by Liu .
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Yasuhiro Kato, JeongHoon Park, Hyota Takamatsu, Atsushi Kumanogoh, Kato, Yasuhiro, Park, JeongHoon, Takamatsu, Hyota, and Kumanogoh, Atsushi
- Published
- 2020
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43. Differential dosimetric benefit of proton beam therapy over intensity modulated radiotherapy for a variety of targets in patients with intracranial germ cell tumors.
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Park, Jeonghoon, Park, Younghee, Lee, Sung Uk, Kim, Taeyoon, Choi, Yun-Kyung, and Kim, Joo-Young
- Abstract
Background: We performed dosimetric comparisons between proton beam therapy and intensity modulated radiotherapy (IMRT) of intracranial germ cell tumors (ICGCTs) arising in various locations of the brain.Materials: IMRT, passively scattered proton therapy (PSPT), and spot scanning proton therapy (SSPT) plans were performed for four different target volumes: the whole ventricle (WV), pineal gland (PG), suprasellar (SS), and basal ganglia (BG). Five consecutive clinical cases were selected from the patients treated between 2011 and 2014 for each target volume. Total 20 cases from the 17 patients were included in the analyses with three overlap cases which were used in plan comparison both for the whole ventricle and boost targets. The conformity index, homogeneity index, gradient index, plan quality index (PQI), and doses applied to the normal substructures of the brain were calculated for each treatment plan.Results: The PQI was significantly superior for PSPT and SSPT than IMRT for ICGCTs in all locations (median; WV: 2.89 and 2.37 vs 4.06, PG: 3.38 and 2.70 vs 4.39, SS: 3.92 and 2.49 vs 4.46, BG: 3.01 and 2.49 vs 4.45). PSPT and SSPT significantly reduced the mean dose, and the 10 and 15 Gy dose volumes applied to the normal brain compared with IMRT (p ≤ 0.05). PSPT and SSPT saved significantly greater volumes of the temporal lobes and hippocampi (p < 0.05) in the SS and PG targets than IMRT. For tumors arising in the BG, PSPT and SSPT also saved greater volumes of the contralateral temporal lobes.Conclusions: PSPT and SSPT provide superior target volume coverage and saved more normal tissue compared with IMRT for ICGCTs in various locations. Future studies should assess whether the extent of normal tissue saved has clinical benefits in children with ICGCTs. [ABSTRACT FROM AUTHOR]- Published
- 2015
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44. Sample Adaptive Offset Design in HEVC.
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Alshin, Alexander, Alshina, Elena, and Park, Jeonghoon
- Published
- 2013
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45. Development of a novel proton dosimetry system using an array of fiber-optic Cerenkov radiation sensors.
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Son, Jaeman, Kim, Meyoung, Shin, Dongho, Hwang, Uijung, Lee, Sebyeong, Lim, Youngkyung, Park, Jeonghoon, Park, Sung yong, Cho, Kwanho, Kim, Daeyong, Jang, Kyoung Won, and Yoon, Myonggeun
- Subjects
- *
CHERENKOV radiation , *MEDICAL dosimetry , *PROTON therapy , *RADIOTHERAPY , *ONCOLOGY - Abstract
This study describes the development and evaluation of a new dosimetric system for proton therapy using an array of fiber-optic Cerenkov radiation sensors (AFCRS). The AFCRS was superior to a conventional, multi-layer ion chamber (MLIC) system in real-time data acquisition and cost effectiveness. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
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