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Choi WS, Yoon SH, Lee D. Homonymous hemianopia due to cerebral venous thrombosis: A case report. Medicine (Baltimore) 2023; 102:e36204. [PMID: 38206682 PMCID: PMC10754574 DOI: 10.1097/md.0000000000036204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/30/2023] [Indexed: 01/13/2024] Open
Abstract
RATIONALE Diagnosing cerebral venous thrombosis (CVT) can be difficult because of nonspecific symptoms, such as headache and homonymous hemianopia (HH). Herein, we present a case of delayed CVT diagnosis due to nonspecific neurological symptoms and nonprominent lesions in a patient with HH. PATIENT CONCERN A 65-year-old woman presented with a sudden onset headache accompanied by right HH that lasted for 1 day. Brain computed tomography and magnetic resonance imaging were initially performed due to suspicion of ischemic lesions or hemorrhage in the left postchiasmal visual pathway; however, no remarkable acute brain lesions were detected. Ophthalmological examinations revealed no notable findings, except for a definite field defect in the Humphrey visual field test. The headaches then waxed and waned but recurred 3 days after the initial symptom.A repeat brain magnetic resonance imaging was performed, which revealed left sectoral gyral swelling and vascular enhancement in the occipital lobe. To further evaluate venous drainage, additional 3-dimensional cerebral computed tomography angiography and 4-vessel angiography were conducted, revealing a partial filling defect in the left transverse sinus and superior venous drainage impairment. These findings suggested the presence of venous thrombosis in the left transverse sinus. DIAGNOSIS The patient was diagnosed with thrombosis of the left transverse sinus, which subsequently caused the right HH. INTERVENTION Anticoagulation therapy with parenteral heparin was started as soon as the diagnosis of CVT was confirmed. Eventually, the patient was solely managed with oral warfarin administration. OUTCOMES Following 3 days of treatment, her headache resolved, and a subsequent visual field testing conducted 2 weeks later revealed a definite improvement in the field defect. LESSONS Despite its favorable prognosis, CVT can be challenging to diagnose. CVT should be considered as a differential diagnosis when diagnosing patients who present with headaches accompanied by HH without prominent brain lesions.
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Affiliation(s)
- Woo Seok Choi
- Department of Ophthalmology, Daegu Catholic University School of Medicine, Daegu, Korea
| | - Sook Hyun Yoon
- Department of Ophthalmology, Daegu Catholic University School of Medicine, Daegu, Korea
| | - Donghun Lee
- Department of Ophthalmology, Daegu Catholic University School of Medicine, Daegu, Korea
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Choi WS, Kim M, Kim IT. Te-rP-C Anodes Prepared Using a Scalable Milling Process for High-Performance Lithium-Ion Batteries. Micromachines (Basel) 2023; 14:2156. [PMID: 38138325 PMCID: PMC10745479 DOI: 10.3390/mi14122156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 12/24/2023]
Abstract
Red phosphorus (rP) is one of the most promising anode materials for lithium-ion batteries, owing to its high theoretical capacity. However, its low electronic conductivity and large volume expansion during cycling limit its practical applications, as it exhibits low electrochemical activity and unstable cyclability. To address these problems, tellurium (Te)-rP-C composites, which have active materials (Te, rP) that are uniformly distributed within the carbon matrix, were fabricated through a simple high-energy ball milling method. Among the three electrodes, the Te-rP (1:2)-C electrode with a 5% FEC additive delivers a high initial CE of 80% and a high reversible capacity of 734 mAh g-1 after 300 cycles at a current density of 100 mA g-1. Additionally, it exhibits a high-rate capacity of 580 mAh g-1 at a high current density of 10,000 mA g-1. Moreover, a comparison of the electrolytes with and without the 5% FEC additive demonstrated improved cycling stability when the FEC additive was used. Ex situ XRD analysis demonstrated the lithiation/delithiation mechanism of Te-rP (1:2)-C after cycling based on the cyclic voltammetry results. Based on the electrochemical impedance spectroscopy analysis results, a Te-rP-C composite with its notable electrochemical performance as an anode can sufficiently contribute to the battery anode industry.
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Affiliation(s)
| | | | - Il Tae Kim
- Department of Chemical and Biological Engineering, Gachon University, Seongnam-si 13120, Republic of Korea; (W.S.C.); (M.K.)
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Jeong SG, Kim J, Min T, Song S, Oh JY, Noh WS, Park S, Park T, Ok JM, Lee J, Choi WS. Exotic Magnetic Anisotropy Near Digitized Dimensional Mott Boundary. Small 2023; 19:e2303176. [PMID: 37312400 DOI: 10.1002/smll.202303176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/30/2023] [Indexed: 06/15/2023]
Abstract
The magnetic anisotropy of low-dimensional Mott systems exhibits unexpected magnetotransport behavior useful for spin-based quantum electronics. Yet, the anisotropy of natural materials is inherently determined by the crystal structure, highly limiting its engineering. The magnetic anisotropy modulation near a digitized dimensional Mott boundary in artificial superlattices composed of a correlated magnetic monolayer SrRuO3 and nonmagnetic SrTiO3 , is demonstrated. The magnetic anisotropy is initially engineered by modulating the interlayer coupling strength between the magnetic monolayers. Interestingly, when the interlayer coupling strength is maximized, a nearly degenerate state is realized, in which the anisotropic magnetotransport is strongly influenced by both the thermal and magnetic energy scales. The results offer a new digitized control for magnetic anisotropy in low-dimensional Mott systems, inspiring promising integration of Mottronics and spintronics.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Jihyun Kim
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Taewon Min
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Sehwan Song
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Jin Young Oh
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Woo-Suk Noh
- MPPC-CPM, Max Planck POSTECH/Korea Research Initiative, Pohang, 37673, South Korea
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Tuson Park
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Jong Mok Ok
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Jaekwang Lee
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
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Park DS, Rata AD, Dahm RT, Chu K, Gan Y, Maznichenko I, Ostanin S, Trier F, Baik H, Choi WS, Choi CJ, Kim YH, Rees GJ, Gíslason HP, Buczek PA, Mertig I, Ionescu MA, Ernst A, Dörr K, Muralt P, Pryds N. Controlled Electronic and Magnetic Landscape in Self-Assembled Complex Oxide Heterostructures. Adv Mater 2023; 35:e2300200. [PMID: 37154173 DOI: 10.1002/adma.202300200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 05/01/2023] [Indexed: 05/10/2023]
Abstract
Complex oxide heterointerfaces contain a rich playground of novel physical properties and functionalities, which give rise to emerging technologies. Among designing and controlling the functional properties of complex oxide film heterostructures, vertically aligned nanostructure (VAN) films using a self-assembling bottom-up deposition method presents great promise in terms of structural flexibility and property tunability. Here, the bottom-up self-assembly is extended to a new approach using a mixture containing a 2Dlayer-by-layer film growth, followed by a 3D VAN film growth. In this work, the two-phase nanocomposite thin films are based on LaAlO3 :LaBO3 , grown on a lattice-mismatched SrTiO3001 (001) single crystal. The 2D-to-3D transient structural assembly is primarily controlled by the composition ratio, leading to the coexistence of multiple interfacial properties, 2D electron gas, and magnetic anisotropy. This approach provides multidimensional film heterostructures which enrich the emergent phenomena for multifunctional applications.
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Affiliation(s)
- Dae-Sung Park
- Institute of Materials, Swiss Federal Institute of Technology-EPFL, Lausanne, 1015, Switzerland
- Department of Energy Conversion and Storage, Technical University of Denmark, Kgs Lyngby, DK-2800, Denmark
- Institute of Electrical and Micro Engineering, Swiss Federal Institute of Technology-EPFL, Lausanne, 1015, Switzerland
| | - Aurora Diana Rata
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06099, Halle, Germany
| | - Rasmus Tindal Dahm
- Department of Energy Conversion and Storage, Technical University of Denmark, Kgs Lyngby, DK-2800, Denmark
| | - Kanghyun Chu
- Institute of Materials, Swiss Federal Institute of Technology-EPFL, Lausanne, 1015, Switzerland
| | - Yulin Gan
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Igor Maznichenko
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06099, Halle, Germany
| | - Sergey Ostanin
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06099, Halle, Germany
| | - Felix Trier
- Department of Energy Conversion and Storage, Technical University of Denmark, Kgs Lyngby, DK-2800, Denmark
| | - Hionsuck Baik
- Korea Basic Science Institute, Seoul, 02841, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Chel-Jong Choi
- School of Semiconductor and Chemical Engineering, Chonbuk National University, Jeonju, 54596, Republic of Korea
| | - Young Heon Kim
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Gregory Jon Rees
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | | | - Paweł Adam Buczek
- Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, 20099, Hamburg, Germany
| | - Ingrid Mertig
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06099, Halle, Germany
| | - Mihai Adrian Ionescu
- Institute of Electrical and Micro Engineering, Swiss Federal Institute of Technology-EPFL, Lausanne, 1015, Switzerland
| | - Arthur Ernst
- Max-Planck-Institut für Mikrostrukturphysik, 06120, Halle, Germany
- Institute of Theoretical Physics, Johannes Kepler University, Linz, 4040, Austria
| | - Kathrin Dörr
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06099, Halle, Germany
| | - Paul Muralt
- Institute of Materials, Swiss Federal Institute of Technology-EPFL, Lausanne, 1015, Switzerland
| | - Nini Pryds
- Department of Energy Conversion and Storage, Technical University of Denmark, Kgs Lyngby, DK-2800, Denmark
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Choi IH, Jeong SG, Min T, Lee J, Choi WS, Lee JS. Giant Enhancement of Electron-Phonon Coupling in Dimensionality-Controlled SrRuO 3 Heterostructures. Adv Sci (Weinh) 2023; 10:e2300012. [PMID: 37052542 DOI: 10.1002/advs.202300012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/23/2023] [Indexed: 06/04/2023]
Abstract
Electrons in crystals interact closely with quantized lattice degree of freedom, determining fundamental electrodynamic behaviors and versatile correlated functionalities. However, the strength of the electron-phonon interaction is so far determined as an intrinsic value of a given material, restricting the development of potential electronic and phononic applications employing the tunable coupling strength. Here, it is demonstrated that the electron-phonon coupling in SrRuO3 can be largely controlled by multiple intuitive tuning knobs available in synthetic crystals. The coupling strength of quasi-2D SrRuO3 is enhanced by ≈300-fold compared with that of bulk SrRuO3 . This enormous enhancement is attributed to the non-local nature of the electron-phonon coupling within the well-defined synthetic atomic network, which becomes dominant in the limit of the 2D electronic state. These results provide valuable opportunities for engineering the electron-phonon coupling, leading to a deeper understanding of the strongly coupled charge and lattice dynamics in quantum materials.
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Affiliation(s)
- In Hyeok Choi
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Taewon Min
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Jaekwang Lee
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jong Seok Lee
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
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Jeong SG, Song S, Park S, Lauter V, Choi WS. Atomic-Scale Modulation of Synthetic Magnetic Order in Oxide Superlattices. Small Methods 2023; 7:e2201386. [PMID: 36564361 DOI: 10.1002/smtd.202201386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Atomic-scale precision control of magnetic interactions facilitates a synthetic spin order useful for spintronics, including advanced memory and quantum logic devices. Conventional modulation of synthetic spin order has been limited to metallic heterostructures that exploit Ruderman-Kittel-Kasuya-Yosida interaction through a nonmagnetic metallic spacer; however, they face issues arising from Joule heating and/or electric breakdown. The practical realization and observation of a synthetic spin order across a nonmagnetic insulating spacer will lead to the development of spin-related devices with a completely different concept. Herein, the atomic-scale modulation of the synthetic spiral spin order in oxide superlattices composed of ferromagnetic metal and nonmagnetic insulator layers is reported. The atomically controlled superlattice exhibits an oscillatory magnetic behavior, representing the existence of a spiral spin structure. Depth-sensitive polarized neutron reflectometry evidences modulated spiral spin structures as a function of the nonmagnetic insulator layer thickness. Atomic-scale customization of the spin state can move the field one step further to actual spintronic applications.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Sehwan Song
- Department of Physics, Pusan National University, Busan, 46241, Korea
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan, 46241, Korea
| | - Valeria Lauter
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
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Eun Lim Y, Seok Choi W, Hoon Kim J, Nam Ahn Y, Tae Kim I. The Sn–red P–Fe–based alloy materials for efficient Li–ion battery anodes. J IND ENG CHEM 2023. [DOI: 10.1016/j.jiec.2023.01.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Kang JH, Kim J, Park TB, Choi WS, Park S, Park T. Study on superconducting properties of CeIrIn 5thin films grown via pulsed laser deposition. J Phys Condens Matter 2022; 34:455602. [PMID: 36055248 DOI: 10.1088/1361-648x/ac8f09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
We report the growth of CeIrIn5thin films with different crystal orientations on a MgF2(001) substrate using pulsed laser deposition technique. X-ray diffraction analysis showed that the thin films were either mainlya-axis-oriented (TF1) or a combination ofa- andc-axis-oriented (TF2). The characteristic features of heavy-fermion superconductors, i.e. Kondo coherence and superconductivity, were clearly observed, where the superconducting transition temperature (Tc) and Kondo coherence temperature (Tcoh) are 0.58 K and 41 K for TF1 and 0.52 K and 37 K for TF2, respectively. The temperature dependencies of the upper critical field (Hc2) of both thin films and the CeIrIn5single crystal revealed a scaling behavior, indicating that the nature of unconventional superconductivity has not been changed in the thin film. The successful synthesis of CeIrIn5thin films is expected to open a new avenue for novel quantum phases that may have been difficult to explore in the bulk crystalline samples.
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Affiliation(s)
- Ji-Hoon Kang
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jihyun Kim
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Tae Beom Park
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sungmin Park
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Tuson Park
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
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Jeong SG, Seo A, Choi WS. Atomistic Engineering of Phonons in Functional Oxide Heterostructures. Adv Sci (Weinh) 2022; 9:e2103403. [PMID: 35038232 PMCID: PMC8895146 DOI: 10.1002/advs.202103403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/19/2021] [Indexed: 06/04/2023]
Abstract
Engineering of phonons, that is, collective lattice vibrations in crystals, is essential for manipulating physical properties of materials such as thermal transport, electron-phonon interaction, confinement of lattice vibration, and optical polarization. Most approaches to phonon-engineering have been largely limited to the high-quality heterostructures of III-V compound semiconductors. Yet, artificial engineering of phonons in a variety of materials with functional properties, such as complex oxides, will yield unprecedented applications of coherent tunable phonons in future quantum acoustic devices. In this study, artificial engineering of phonons in the atomic-scale SrRuO3 /SrTiO3 superlattices is demonstrated, wherein tunable phonon modes are observed via confocal Raman spectroscopy. In particular, the coherent superlattices led to the backfolding of acoustic phonon dispersion, resulting in zone-folded acoustic phonons in the THz frequency domain. The frequencies can be largely tuned from 1 to 2 THz via atomic-scale precision thickness control. In addition, a polar optical phonon originating from the local inversion symmetry breaking in the artificial oxide superlattices is observed, exhibiting emergent functionality. The approach of atomic-scale heterostructuring of complex oxides will vastly expand material systems for quantum acoustic devices, especially with the viability of functionality integration.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Ambrose Seo
- Department of Physics and Astronomy, University of Kentucky, Lexington, KY, 40506, USA
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
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Wang R, Choi WS. Wafer as an adjunct to plating patient-specific implants for the multi-segment maxilla: a useful tool. Int J Oral Maxillofac Surg 2022; 51:1055-1058. [PMID: 35148911 DOI: 10.1016/j.ijom.2022.01.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 10/25/2021] [Accepted: 01/25/2022] [Indexed: 11/19/2022]
Abstract
Virtual surgical planning for orthognathic surgery using patient-specific implants (PSI) is usually waferless nowadays. However, without an occlusal wafer, difficulties arise in controlling the accuracy of multi-segment maxillary osteotomies, especially for expansion and rotational movements of each segment. It is technically challenging intraoperatively to manipulate multiple segments to fit into the PSI, as the relatively small bone segments need to be secured into the PSI while simultaneously achieving individual segment movements in all planes and with potential bony interferences with each other. Therefore, the use of a maxillary tooth-supported surgical guide is proposed and described. When the guide is inserted before the PSI, it overcomes difficulties in handling multiple maxillary segments and facilitates achieving maximal positional precision of each individual bone segment. The guide enables multiple smaller segments to behave as one unit with the designated occlusion whilst visualizing bony interferences before PSI plating is commenced. Adding a tooth-borne surgical guide in the form of a wafer and a customized arch bar is a cost-effective method to enhance accuracy in virtually planned multi-segment maxillary surgery. Further investigations are required to validate the accuracy and advantages of using wafers and PSI in multi-segment maxillary and mandibular orthognathic surgeries.
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Affiliation(s)
- R Wang
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Hong Kong, Hong Kong Special Administrative Region
| | - W S Choi
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Hong Kong, Hong Kong Special Administrative Region.
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Jeong SG, Kim J, Seo A, Park S, Jeong HY, Kim YM, Lauter V, Egami T, Han JH, Choi WS. Unconventional interlayer exchange coupling via chiral phonons in synthetic magnetic oxide heterostructures. Sci Adv 2022; 8:eabm4005. [PMID: 35089783 PMCID: PMC8797183 DOI: 10.1126/sciadv.abm4005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/08/2021] [Indexed: 05/25/2023]
Abstract
Chiral symmetry breaking of phonons plays an essential role in emergent quantum phenomena owing to its strong coupling to spin degree of freedom. However, direct experimental evidence of the chiral phonon-spin coupling is lacking. In this study, we report a chiral phonon-mediated interlayer exchange interaction in atomically controlled ferromagnetic metal (SrRuO3)-nonmagnetic insulator (SrTiO3) heterostructures. Owing to the unconventional interlayer exchange interaction, we have observed rotation of spins as a function of nonmagnetic insulating spacer thickness, resulting in a spin spiral state. The chiral phonon-spin coupling is further confirmed by phonon Zeeman effect. The existence of the chiral phonons and their interplay with spins along with our atomic-scale heterostructure approach unveil the crucial roles of chiral phonons in magnetic materials.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Jiwoong Kim
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Ambrose Seo
- Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506, USA
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Hu Young Jeong
- Graduate School of Semiconductor Materials and Devices Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
| | - Young-Min Kim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Korea
| | - Valeria Lauter
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Takeshi Egami
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA
| | - Jung Hoon Han
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
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Choi WS, Lee CH, Lee CE, Seo S, Lee KW. Effect of Mask Mandates on the Intraocular Pressure Measured via Goldmann Applanation Tonometry. J Korean Ophthalmol Soc 2022. [DOI: 10.3341/jkos.2022.63.1.44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Purpose: The corona virus disease-19 (COVID-19) pandemic has resulted in mandatory masking of patients and physicians during outpatient visits. This study evaluated the changes in intraocular pressure (IOP) according to mask use.Methods: This prospective study enrolled 30 healthy volunteers (60 eyes). IOP was measured via Goldmann applanation tonometry (GAT) for the subjects wearing one of four commonly used masks: dental, bi-folding Korean Filter (KF)94, tri-folding KF94, and dust masks. Subjects with IOP measurement errors of more than 5 mmHg were rechecked with another GAT type.Results: The mean IOP measured via GAT before mask wearing was 13.7 ± 1.7 mmHg. It was 13.5 ± 2.1, 14.0 ± 2.3, 14.3 ± 2.5, and 13.8 ± 1.6 mmHg with the dental, bi-folding KF94, tri-folding KF94, and dust masks, respectively. There were no significant differences in IOP according to mask type (p = 0.635). IOP errors above 5 mmHg were detected in three subjects who had contact between the GAT feeler arm and tri-folding KF94 mask during IOP measurement.Conclusions: The IOP as measured via GAT is artificially elevated by mechanical interference from the tri-fold KF94 mask. To minimize such mask-induced artifacts in GAT measurements, compress the patient’s mask or change the mask type to prevent any contact during measurement.
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Choi WS, Park J, Lee KW, Kang HG. Two-year Changes in Postoperative Central Macular Thickness and Subfoveal Choroidal Thickness in Epiretinal Membrane Patients. J Korean Ophthalmol Soc 2021. [DOI: 10.3341/jkos.2021.62.12.1607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Purpose: To evaluate changes in central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) after phacovitrectomy over a 2-year period in idiopathic epiretinal membrane (ERM) patients.Methods: The records of 52 idiopathic ERM patients (52 eyes) who underwent phacovitrectomy, without recurrence of the condition over a 2-year follow-up period, were reviewed retrospectively. Changes in CMT and SFCT, as measured by optical coherence tomography, were analyzed and compared with those of a normal control group over a 2-year period.Results: The mean preoperative CMT and SFCT were 425.67 ± 84.67 and 257.56 ± 90.13 μm, respectively. Postoperative CMT was reduced significantly to 372.17 ± 45.26 μm at 1 year and 363.15 ± 47.35 μm at 2 years (p < 0.001). SFCT at 1 and 2 years postoperatively was significantly reduced to 238.85 ± 84.85 and 230.31 ± 87.95 μm, respectively (p < 0.001). In the control group, there was no significant change in CMT; however, the SFCT decreased by 11.09 ± 22.36 μm during the 2-year follow-up (p = 0.007). In contrast, in the patient group, CMT and SFCT decreased by 62.52 ± 71.45 and 27.25 ± 41.97 μm, respectively, showing a significant difference from the control group (p < 0.001 and p = 0.043, respectively). Both before surgery and at 1 year postoperatively, the thinner the CMT, the better the best-corrected visual acuity (BCVA) (p = 0.010 and p = 0.018, respectively). A better postoperative BCVA at 2 years was associated with a thinner CMT and better BCVA before surgery (p < 0.001 and p < 0.001, respectively).Conclusions: Following a phacovitrectomy procedure, ERM patients showed significant reductions in both the CMT and SFCT at the 2-year follow-up.
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Choi WS, Kim JH, Lee CH, Lee CE, Seo S. Adherence Improvement in Glaucoma Patients: Effects of Educational Intervention Using an Eye Drop Chart. J Korean Ophthalmol Soc 2021. [DOI: 10.3341/jkos.2021.62.12.1617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Purpose: To evaluate the effects of an educational intervention using an eye drop chart and supplementary education on glaucoma patients’ adherence.Methods: In this multicenter prospective study, medically treated glaucoma patients were educated on the administration of eye drops using an eye drop chart. At the time of recruitment, all of the patients completed a questionnaire on demographic characteristics and adherence. Three months after the initial educational intervention, the patients were randomly divided into two groups: an education group and a control group. The education group received supplementary education. Immediately thereafter and at 6 months, all of the patients completed the questionnaire on adherence again. Changes in instillation behavior, the relationship between the adherence score and demographic characteristics, and factors contributing to an improvement in adherence and intraocular pressure were then analyzed.Results: The adherence scores were significantly higher in patients with fewer medications, a higher annual income and higher educational level, and an urban residence (p = 0.038, p = 0.033, p = 0.041 and p = 0.047, respectively). Education on the administration of eye drops and use of the eye drop chart improved adherence scores from 23.05 ± 3.52 to 21.30 ± 3.95 (p = 0.021) and significantly reduced the average intraocular pressure from 14.3 ± 2.9 to 12.4 ± 3.1 mmHg (p < 0.001). Working indoors (odds ratio [OR] = 5.47, p = 0.032) and supplementary education at 3 months (OR = 4.53, p = 0.030) were also correlated with improved adherence.Conclusions: An eye drop chart is an effective tool for improving adherence and intraocular pressure control in glaucoma patients. Improvement in adherence was especially notable in patients whose work predominantly involved indoor activity. The effectiveness of the eye drop chart was improved by supplementary education.
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15
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Lee J, Adiga P, Lee SA, Nam SH, Ju HA, Jung MH, Jeong HY, Kim YM, Wong C, Elzein R, Addou R, Stoerzinger KA, Choi WS. Contribution of the Sub-Surface to Electrocatalytic Activity in Atomically Precise La 0.7 Sr 0.3 MnO 3 Heterostructures. Small 2021; 17:e2103632. [PMID: 34677915 DOI: 10.1002/smll.202103632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Electrocatalytic reactions are known to take place at the catalyst/electrolyte interface. Whereas recent studies of size-dependent activity in nanoparticles and thickness-dependent activity of thin films imply that the sub-surface layers of a catalyst can contribute to the catalytic activity as well, most of these studies consider actual modification of the surfaces. In this study, the role of catalytically active sub-surface layers was investigated by employing atomic-scale thickness control of the La0.7 Sr0.3 MnO3 (LSMO) films and heterostructures, without altering the catalyst/electrolyte interface. The activity toward the oxygen evolution reaction (OER) shows a non-monotonic thickness dependence in the LSMO films and a continuous screening effect in LSMO/SrRuO3 heterostructures. The observation leads to the definition of an "electrochemically-relevant depth" on the order of 10 unit cells. This study on the electrocatalytic activity of epitaxial heterostructures provides new insight in designing efficient electrocatalytic nanomaterials and core-shell architectures.
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Affiliation(s)
- Jegon Lee
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Prajwal Adiga
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
| | - Sang A Lee
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Physics, Pukyong National University, Busan, 48513, Republic of Korea
| | - Seung Hyun Nam
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyeon-Ah Ju
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Min-Hyoung Jung
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hu Young Jeong
- Graduate School of Semiconductor Materials and Devices Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Young-Min Kim
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Cindy Wong
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
| | - Radwan Elzein
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
| | - Rafik Addou
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
| | - Kelsey A Stoerzinger
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99254, USA
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
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16
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Ok JM, Mohanta N, Zhang J, Yoon S, Okamoto S, Choi ES, Zhou H, Briggeman M, Irvin P, Lupini AR, Pai YY, Skoropata E, Sohn C, Li H, Miao H, Lawrie B, Choi WS, Eres G, Levy J, Lee HN. Correlated oxide Dirac semimetal in the extreme quantum limit. Sci Adv 2021; 7:eabf9631. [PMID: 34524855 PMCID: PMC8443170 DOI: 10.1126/sciadv.abf9631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 07/23/2021] [Indexed: 05/25/2023]
Abstract
Quantum materials (QMs) with strong correlation and nontrivial topology are indispensable to next-generation information and computing technologies. Exploitation of topological band structure is an ideal starting point to realize correlated topological QMs. Here, we report that strain-induced symmetry modification in correlated oxide SrNbO3 thin films creates an emerging topological band structure. Dirac electrons in strained SrNbO3 films reveal ultrahigh mobility (μmax ≈ 100,000 cm2/Vs), exceptionally small effective mass (m* ~ 0.04me), and nonzero Berry phase. Strained SrNbO3 films reach the extreme quantum limit, exhibiting a sign of fractional occupation of Landau levels and giant mass enhancement. Our results suggest that symmetry-modified SrNbO3 is a rare example of correlated oxide Dirac semimetals, in which strong correlation of Dirac electrons leads to the realization of a novel correlated topological QM.
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Affiliation(s)
- Jong Mok Ok
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | | | - Jie Zhang
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Sangmoon Yoon
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | | | - Eun Sang Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - Hua Zhou
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Megan Briggeman
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Pittsburgh Quantum Institute, Pittsburgh, PA 15260, USA
| | - Patrick Irvin
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Pittsburgh Quantum Institute, Pittsburgh, PA 15260, USA
| | | | - Yun-Yi Pai
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | | | - Changhee Sohn
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Haoxiang Li
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Hu Miao
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | | | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Gyula Eres
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Jeremy Levy
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Pittsburgh Quantum Institute, Pittsburgh, PA 15260, USA
| | - Ho Nyung Lee
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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17
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Yoon S, Gao X, Ok JM, Liao Z, Han MG, Zhu Y, Ganesh P, Chisholm MF, Choi WS, Lee HN. Strain-Induced Atomic-Scale Building Blocks for Ferromagnetism in Epitaxial LaCoO 3. Nano Lett 2021; 21:4006-4012. [PMID: 33929867 DOI: 10.1021/acs.nanolett.1c00756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The origin of strain-induced ferromagnetism, which is robust regardless of the type and degree of strain in LaCoO3 (LCO) thin films, is enigmatic despite intensive research efforts over the past decade. Here, by combining scanning transmission electron microscopy with ab initio density functional theory plus U calculations, we report that the ferromagnetism does not emerge directly from the strain itself but rather from the creation of compressed structural units within ferroelastically formed twin-wall domains. The compressed structural units are magnetically active with the rocksalt-type high-spin/low-spin order. Our study highlights that the ferroelastic nature of ferromagnetic structural units is important for understanding the intriguing ferromagnetic properties in LCO thin films.
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Affiliation(s)
- Sangmoon Yoon
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Xiang Gao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jong Mok Ok
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Zhaoliang Liao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Myung-Geun Han
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Yimei Zhu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Panchapakesan Ganesh
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Matthew F Chisholm
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Ho Nyung Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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18
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Yang WF, Choi WS, Zhu WY, Zhang CY, Li DTS, Tsoi JKH, Tang AWL, Kwok KW, Su YX. Spatial deviations of the temporomandibular joint after oncological mandibular reconstruction. Int J Oral Maxillofac Surg 2021; 51:44-53. [PMID: 33865661 DOI: 10.1016/j.ijom.2021.02.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 01/01/2021] [Accepted: 02/17/2021] [Indexed: 12/15/2022]
Abstract
Spatial deviations of the temporomandibular joint (TMJ) after oncological mandibular reconstruction are important to the aesthetic and functional rehabilitation. The aim of this study was to clarify whether and how three dimensionally (3D) printed patient-specific surgical plates, and the preservation of the condyle or ramus, affect spatial deviations of the TMJ. A total of 33 patients who underwent mandibular reconstruction via computer-assisted surgery were included. Regarding absolute deviations, patients in the 3D-printed plate group showed smaller TMJ deviations compared to those in the conventional plate group. There was no difference in absolute deviations of the TMJ regardless of whether the condyle or ramus was preserved. Regarding physiological deviations, the impact on the contralateral TMJ was smaller in the 3D-printed plate group. Patients with both the condyle and ramus removed had significantly higher deviations of the condyle and joint space. In summary, 3D-printed patient-specific surgical plates improved the spatial accuracy of the TMJ. Under physiological conditions, TMJ deviations on the operated side were mainly affected by the preservation of the condyle. Removal of both the condyle and ramus caused more severe spatial interference to the TMJ; this should be further confirmed.
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Affiliation(s)
- W-F Yang
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - W S Choi
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - W-Y Zhu
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - C-Y Zhang
- Guangzhou Janus Biotechnology Co., Ltd, Guangzhou, China
| | - D T S Li
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - J K-H Tsoi
- Dental Materials Science, Division of Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - A W-L Tang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - K-W Kwok
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Y-X Su
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China.
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Kim SJ, Kim S, Lee J, Jo Y, Seo YS, Lee M, Lee Y, Cho CR, Kim JP, Cheon M, Hwang J, Kim YI, Kim YH, Kim YM, Soon A, Choi M, Choi WS, Jeong SY, Lee YH. Color of Copper/Copper Oxide. Adv Mater 2021; 33:e2007345. [PMID: 33751679 DOI: 10.1002/adma.202007345] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/30/2021] [Indexed: 06/12/2023]
Abstract
Stochastic inhomogeneous oxidation is an inherent characteristic of copper (Cu), often hindering color tuning and bandgap engineering of oxides. Coherent control of the interface between metal and metal oxide remains unresolved. Coherent propagation of an oxidation front in single-crystal Cu thin film is demonstrated to achieve a full-color spectrum for Cu by precisely controlling its oxide-layer thickness. Grain-boundary-free and atomically flat films prepared by atomic-sputtering epitaxy allow tailoring of the oxide layer with an abrupt interface via heat treatment with a suppressed temperature gradient. Color tuning of nearly full-color red/green/blue indices is realized by precise control of the oxide-layer thickness; the samples cover ≈50.4% of the standard red/green/blue color space. The color of copper/copper oxide is realized by the reconstruction of the quantitative yield color from the oxide "pigment" (complex dielectric functions of Cu2 O) and light-layer interference (reflectance spectra obtained from the Fresnel equations) to produce structural color. Furthermore, laser-oxide lithography is demonstrated with micrometer-scale linewidth and depth through local phase transformation to oxides embedded in the metal, providing spacing necessary for semiconducting transport and optoelectronics functionality.
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Affiliation(s)
- Su Jae Kim
- Crystal Bank Research Institute, Pusan National University, Busan, 46241, Republic of Korea
| | - Seonghoon Kim
- Research Institute of Basic Science, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jegon Lee
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Yongjae Jo
- Center for Neurscience Imaging Research, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Yu-Seong Seo
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Myounghoon Lee
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Yousil Lee
- Crystal Bank Research Institute, Pusan National University, Busan, 46241, Republic of Korea
| | - Chae Ryong Cho
- Department of Nanoenergy Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Jong-Pil Kim
- Division of High-Tech Materials Research, Busan Center, Korea Basic Science Institute, Busan, 46742, Republic of Korea
| | - Miyeon Cheon
- Crystal Bank Research Institute, Pusan National University, Busan, 46241, Republic of Korea
| | - Jungseek Hwang
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Yong In Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Young-Hoon Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Young-Min Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Aloysius Soon
- Center for Artificial Synesthesia Materials Discovery and Department of Materials Science and Engineering, Yonsei University, Seoul, 03722, Republic of Korea
| | - Myunghwan Choi
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Se-Young Jeong
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Young Hee Lee
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
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20
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Leung YY, Wang R, Wong NSM, Li DTS, Au SW, Choi WS, Su YX. Surgical morbidities of sagittal split ramus osteotomy versus intraoral vertical ramus osteotomy for the correction of mandibular prognathism: a randomized clinical trial. Int J Oral Maxillofac Surg 2020; 50:933-939. [PMID: 33168369 DOI: 10.1016/j.ijom.2020.06.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 04/14/2020] [Accepted: 06/23/2020] [Indexed: 11/30/2022]
Abstract
The sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) are two common orthognathic procedures for the treatment of mandibular prognathism. This randomized clinical trial compared the surgical morbidities between SSRO and IVRO for patients with mandibular prognathism over the first 2 years postoperative. Ninety-eight patients (40 male, 58 female) with a mean age of 24.4±3.5 years underwent bilateral SSRO (98 sides) or IVRO (98 sides) as part or all of their orthognathic surgery. IVRO presented less short-term and long-term surgical morbidity in general. The SSRO group had a greater incidence of inferior alveolar nerve deficit at all follow-up time points (P< 0.01). There was more TMJ pain at 6 weeks (P= 0.047) and 3 months (P= 0.001) postoperative in the SSRO group. The SSRO group also presented more minor complications, which were related to titanium plate exposure and infection. There were no major complications for either technique in this study. Despite the need for intermaxillary fixation, IVRO appears to be associated with less surgical morbidity than SSRO when performed as a mandibular setback procedure to treat mandibular prognathism.
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Affiliation(s)
- Y Y Leung
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong.
| | - R Wang
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - N S M Wong
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - D T S Li
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - S W Au
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - W S Choi
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - Y-X Su
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
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21
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Kim AY, Choi WS. Considerations on the Implementation of the Telemedicine System Encountered with Stakeholders' Resistance in COVID-19 Pandemic. Telemed J E Health 2020; 27:475-480. [PMID: 32946347 DOI: 10.1089/tmj.2020.0293] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Background: Non-face-to-face consultation, which ensures physical distance between patients and doctors, is increasing as a substitute mode for dealing with highly infectious diseases. Korea, with its remarkable Information and Communications Technology infrastructure, introduced telemedicine in 1988, yet it has not been formally accepted owing to stakeholders' resistance and legal restrictions. Purpose: This study aims to determine the feasibility of implementing the telemedicine system and find solutions of its development and resistance by stakeholders. Method and Material: The authors present a unique case of Korea where telemedicine, despite its solid technological base, has not yet gained a foothold 32 years after its first pilot project. A narrative review was condected according to the timeline of government-driven telemedicine adoption in Korea, and an analysis was performed on the tendency of stakeholder resistance. Results: The analysis revealed that the relevant stakeholders were classified into doctors, patients, governments and some political parties. Among stakeholders as a whole, private healthcare physicians, who provide over 90% of primary care in Korea, amount to the largest demographic against the implementation of telemedicine. Their resistance was found to be the product of policies and problems arising from the coexistence of telemedicine and conventional healthcare regimes. With the COVID-19 pandemic, policymakers are at odds with these stakeholders while implementing a pilot project. Conclusion: Fostering smooth policy implementation necessitates adopting an approach that reduces conflicts with private healthcare providers.
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Affiliation(s)
- Ah Young Kim
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Woo Seok Choi
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Department of Pulmonology, Keyu Internal Medicine Clinic, Daejeon, Republic of Korea
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22
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Jeong SG, Han G, Song S, Min T, Mohamed AY, Park S, Lee J, Jeong HY, Kim Y, Cho D, Choi WS. Propagation Control of Octahedral Tilt in SrRuO 3 via Artificial Heterostructuring. Adv Sci (Weinh) 2020; 7:2001643. [PMID: 32832374 PMCID: PMC7435247 DOI: 10.1002/advs.202001643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/11/2020] [Indexed: 05/25/2023]
Abstract
Bonding geometry engineering of metal-oxygen octahedra is a facile way of tailoring various functional properties of transition metal oxides. Several approaches, including epitaxial strain, thickness, and stoichiometry control, have been proposed to efficiently tune the rotation and tilt of the octahedra, but these approaches are inevitably accompanied by unnecessary structural modifications such as changes in thin-film lattice parameters. In this study, a method to selectively engineer the octahedral bonding geometries is proposed, while maintaining other parameters that might implicitly influence the functional properties. A concept of octahedral tilt propagation engineering is developed using atomically designed SrRuO3/SrTiO3 (SRO/STO) superlattices. In particular, the propagation of RuO6 octahedral tilt within the SRO layers having identical thicknesses is systematically controlled by varying the thickness of adjacent STO layers. This leads to a substantial modification in the electromagnetic properties of the SRO layer, significantly enhancing the magnetic moment of Ru. This approach provides a method to selectively manipulate the bonding geometry of strongly correlated oxides, thereby enabling a better understanding and greater controllability of their functional properties.
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Affiliation(s)
- Seung Gyo Jeong
- Department of PhysicsSungkyunkwan UniversitySuwon16419Republic of Korea
| | - Gyeongtak Han
- Department of Energy SciencesSungkyunkwan UniversitySuwon16419Korea
- Center for Integrated Nanostructure PhysicsInstitute for Basic ScienceSuwon16419Korea
| | - Sehwan Song
- Department of PhysicsPusan National UniversityBusan46241Korea
| | - Taewon Min
- Department of PhysicsPusan National UniversityBusan46241Korea
| | - Ahmed Yousef Mohamed
- IPIT and Department of PhysicsJeonbuk National UniversityJeonju54896Republic of Korea
| | - Sungkyun Park
- Department of PhysicsPusan National UniversityBusan46241Korea
| | - Jaekwang Lee
- Department of PhysicsPusan National UniversityBusan46241Korea
| | - Hu Young Jeong
- UNIST Central Research Facilities and School of Materials Science and EngineeringUlsan National Institute of Science and TechnologyUlsan44919Korea
| | - Young‐Min Kim
- Department of Energy SciencesSungkyunkwan UniversitySuwon16419Korea
- Center for Integrated Nanostructure PhysicsInstitute for Basic ScienceSuwon16419Korea
| | - Deok‐Yong Cho
- IPIT and Department of PhysicsJeonbuk National UniversityJeonju54896Republic of Korea
| | - Woo Seok Choi
- Department of PhysicsSungkyunkwan UniversitySuwon16419Republic of Korea
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23
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Lee JH, Yoon CJ, Choi WS, Lee CH. Benign postoperative hepaticojejunostomy stricture: percutaneous recanalisation using the reverse end of a microwire. Clin Radiol 2020; 75:879.e1-879.e6. [PMID: 32727657 DOI: 10.1016/j.crad.2020.06.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 06/23/2020] [Indexed: 11/26/2022]
Abstract
AIM To evaluate the technical feasibility and safety of percutaneous recanalisation of benign postoperative hepaticojejunostomy strictures using the reverse end of a microwire. MATERIALS AND METHODS Twenty-one patients with benign postoperative hepaticojejunostomy strictures that had failed to recanalise following management with conventional percutaneous techniques from January 2012 to March 2019 were included in the study. The stricture was punctured by the reverse end of a microwire. Subsequently, serial balloon dilatation and covered stent placement was performed. Technical as well as clinical success, complications, and patency of the hepaticojejunostomy were evaluated. RESULTS Technical success was achieved in 19 of 21 (90.5%) patients. The mean number of treatment sessions was 1.2 (range, 1-2). The obstructive symptoms were resolved within 3 days after the procedure in 19 patients (100%). There were no major complications. The 1-year and 3-year patency rates were 76.9% and 61.5%, respectively. CONCLUSION Percutaneous recanalisation using the reverse end of a microwire is technically feasible and safe in the treatment of benign postoperative hepaticojejunostomy strictures. This technique is useful when the conventional percutaneous technique cannot be used to cross the stricture.
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Affiliation(s)
- J H Lee
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, South Korea
| | - C J Yoon
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, South Korea.
| | - W S Choi
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, South Korea
| | - C-H Lee
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, South Korea
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Abstract
Spin-phonon coupling is one of the fundamental interactions in functional materials, indispensable for understanding their unexpected magnetic ground states. Ferromagnetic SrRuO3 is a correlated metal with the potential for utilization in novel spintronic devices and serves as a promising platform for studying spin-phonon interactions. In this study, we used Raman spectroscopy to identify spin-phonon coupling in SrRuO3 heterostructures. We deliberately decreased the exchange interactions within SrRuO3 by reducing system dimensions, which was coherently observed in both temperature-dependent magnetization measurements and phonon spectra. To collect the Raman signals from the very thin (quasi-2D) SrRuO3 layers while maintaining the layer thickness, we fabricated epitaxial oxide superlattices with 50 repetitions of the layers. We also present polarization-dependent Raman spectra of SrRuO3, with accurate identification of the Raman modes. These results show that the phonon dynamics of SrRuO3 is strongly influenced by the spin ordering, which can be efficiently tailored via atomically controlled epitaxial heterostructuring.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea.
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25
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Seok H, Song J, Jeon JH, Choi HK, Choi WS, Moon S, Park DW. Timing of antibiotics in septic patients: a prospective cohort study. Clin Microbiol Infect 2020; 26:1495-1500. [PMID: 32062049 DOI: 10.1016/j.cmi.2020.01.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 12/24/2022]
Abstract
OBJECTIVES To evaluate the effect of timing and appropriateness of antibiotics administration on mortality in patients diagnosed with sepsis according to the Sepsis-3 definition. METHODS This prospective cohort study was conducted in patients diagnosed with sepsis according to the Sepsis-3 definition at the emergency department of Korea University Ansan Hospital from January 2016 to January 2019. The time to antibiotics was defined as the time in hours from emergency department arrival to the first antibiotic administration. Cox proportional hazards regression analysis was used to estimate the association between time to antibiotics and 7-, 14- and 28-day mortality. RESULTS Of 482 patients enrolled onto this study, 203 (42.1%) of 482 and 312 (64.7%) of 482 were diagnosed with septic shock and high-grade infection respectively. The median time to receipt of antibiotic therapy was 115 minutes. Antibiotics were administered within 3 and 6 hours in 340 (70.4%) of 482 and 450 (93.2%) of 482 patients respectively. Initial appropriate empirical antibiotics were administered in 375 (77.8%) of 482 patients. The time to and appropriateness of the initial antibiotics were not associated with 7-, 14- and 28-day mortality in multivariate analysis. The Sequential Organ Failure Assessment (SOFA) score (adjusted hazard ratio (aHR) 1.229, 95% confidence interval (CI) 1.093-1.381, p 0.001) and initial lactate levels (aHR 1.128, 95% CI 1.034-1.230, p 0.007), Charlson comorbidity index (aHR 1.115, 95% CI 1.027-1.210, p 0.014), 2-hour lactate level (aHR 1.115, 95% CI 1.027-1.210, p 0.009) and SOFA score (aHR 1.077, 95% CI 1.013-1.144, p 0.018) affected 7-, 14- and 28-day mortality respectively. Subgroup analysis with septic shock, bacteraemia and high-grade infection did not affect mortality rates. CONCLUSIONS Time to receipt of antibiotics may not affect the prognosis of patients with sepsis if a rapid and well-trained resuscitation is combined with appropriate antibiotic administration within a reasonable time.
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Affiliation(s)
- H Seok
- Division of Infectious Diseases, Department of Medicine, Republic of Korea
| | - J Song
- Department of Emergency Medicine, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Republic of Korea
| | - J H Jeon
- Division of Infectious Diseases, Department of Medicine, Republic of Korea
| | - H K Choi
- Division of Infectious Diseases, Department of Medicine, Republic of Korea
| | - W S Choi
- Division of Infectious Diseases, Department of Medicine, Republic of Korea
| | - S Moon
- Department of Emergency Medicine, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Republic of Korea
| | - D W Park
- Division of Infectious Diseases, Department of Medicine, Republic of Korea.
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26
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Jeong SG, Min T, Woo S, Kim J, Zhang YQ, Cho SW, Son J, Kim YM, Han JH, Park S, Jeong HY, Ohta H, Lee S, Noh TW, Lee J, Choi WS. Phase Instability amid Dimensional Crossover in Artificial Oxide Crystal. Phys Rev Lett 2020; 124:026401. [PMID: 32004053 DOI: 10.1103/physrevlett.124.026401] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Indexed: 06/10/2023]
Abstract
Artificial crystals synthesized by atomic-scale epitaxy provide the ability to control the dimensions of the quantum phases and associated phase transitions via precise thickness modulation. In particular, the reduction in dimensionality via quantized control of atomic layers is a powerful approach to revealing hidden electronic and magnetic phases. Here, we demonstrate a dimensionality-controlled and induced metal-insulator transition (MIT) in atomically designed superlattices by synthesizing a genuine two-dimensional (2D) SrRuO_{3} crystal with highly suppressed charge transfer. The tendency to ferromagnetically align the spins in an SrRuO_{3} layer diminishes in 2D as the interlayer exchange interaction vanishes, accompanying the 2D localization of electrons. Furthermore, electronic and magnetic instabilities in the two SrRuO_{3} unit cell layers induce a thermally driven MIT along with a metamagnetic transition.
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Affiliation(s)
- Seung Gyo Jeong
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Taewon Min
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Sungmin Woo
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Jiwoong Kim
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Yu-Qiao Zhang
- Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0020, Japan
| | - Seong Won Cho
- Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
| | - Jaeseok Son
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
| | - Young-Min Kim
- Department of Energy Sciences, Sungkyunkwan University, Suwon 16419, Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Suwon 16419, Korea
| | - Jung Hoon Han
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Hu Young Jeong
- UNIST Central Research Facilities and School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea
| | - Hiromichi Ohta
- Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0020, Japan
| | - Suyoun Lee
- Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Tae Won Noh
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Korea
| | - Jaekwang Lee
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
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Choi WS, Shin IS, Yang JS. Understanding Moderators of Home Blood Pressure Telemonitoring Systems in Urban Hypertensive Patients: A Systematic Review and Meta-Analysis. Telemed J E Health 2019; 26:1016-1034. [PMID: 31855113 DOI: 10.1089/tmj.2019.0205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Background: Factors affecting the effectiveness of telemonitoring in home blood pressure telemonitoring (HBPT) must be examined in an integrated analysis in urban hypertensive patients. Materials and Methods: In a systematic review of electronic databases, we retrieved 1,433 citations and selected 34 comparisons. Specified moderators were the duration of the intervention, the frequency of remote transmission of blood pressure (BP) data, the additional intervention, and the intervention pathway. Results: For the duration of follow-up of HBPT, the weighted mean difference (WMD) in systolic blood pressure (SBP) between two groups was 11.900 mmHg (p-value <0.001) at 2 months and 3.024 mmHg (p = 0.002) at 12 months. The WMD in SBP was 5.512 mmHg (p < 0.001) in cases where data were transmitted daily and 1.818 mmHg (p = 0.084) for monthly transmission. For the group in which further interventions with HBPT were conducted, the WMD in SBP was 3.813 mmHg (p < 0.001). For patients who did not receive additional interventions, the WMD was 2.747 mmHg (p = 0.005). For the pathway of HBPT, the WMD was 6.800 mmHg (p = 0.053) when BP values were remote transmitted through letter, 3.041 mmHg (p = 0.001) through mobile phone/web, 2.224 mmHg (p = 0.043) through telephone-linked computer system, and 4.352 mmHg (p < 0.001) through telephone. Conclusions: The effects of moderators of HBPT systems utilized with urban hypertensive patients differ from those in interventions that did not distinguish urban from rural areas. Results for duration of implementation and frequency of data transmission were significant. Among the interventions using telecommunications, the telephone was the most effective in comparison to other channels.
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Affiliation(s)
- Woo Seok Choi
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Keyu Internal Medicine Clinic, Daejeon, Republic of Korea
| | - In-Soo Shin
- Department of Transdisciplinary Security, Dongguk University, Seoul, Republic of Korea
| | - Jae-Suk Yang
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
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28
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Cho SK, Jung SY, Choi S, Im SG, Kim H, Choi WS, Jang EJ, Sung YK. Factors related to the use of opioids as early treatment in patients with knee osteoarthritis. Arthritis Res Ther 2019; 21:222. [PMID: 31685008 PMCID: PMC6827242 DOI: 10.1186/s13075-019-2004-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 09/13/2019] [Indexed: 01/10/2023] Open
Abstract
Objective To examine factors related to the use of opioids as an early treatment option for knee OA patients Methods Using the Korean nationwide claim database, we selected knee OA patients between 2013 and 2015. Among them, patients without any claim of knee OA for 2 years before the index date were included as our study population. We analyzed their first claim for prescriptions, including tramadol and stronger opioids, at the index date of each patient. Using a multinomial model, we identified factors associated with the early use of tramadol and stronger opioids in knee OA patients. Results Among a total of 2,857,999 knee OA patients, 12.2% (n = 348,516) were treated with opioids as their first treatment. However, the prevalence of stronger opioid use was only 0.07% (n = 1972). Male sex (OR 1.28 in tramadol, OR 1.13 in stronger opioids) and comorbidities with depression (OR 1.05, 1.46), low back pain (OR 1.13, 1.30), intervertebral disc disorder (OR 1.11, 1.40), and spinal stenosis (OR 1.27, 1.55) were the factors for the early use of tramadol or stronger opioids in knee OA patients. Patients in a tertiary referral hospital tended to use tramadol or stronger opioids than those in clinics (OR 1.04, 56.63, respectively). Conclusion In Korea, 12.2% of knee OA patients were treated with opioids as an early treatment, and tramadol was used more commonly than stronger opioids. Male sex and having comorbidities such as depression or musculoskeletal disease are patient factors associated with the early use of opioids in knee OA patients.
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Affiliation(s)
- Soo-Kyung Cho
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, 222-1 wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Sun-Young Jung
- College of Pharmacy, Chung-Ang University, 84, Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Seongmi Choi
- Department of Statistics, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Seul Gi Im
- Department of Statistics, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Hyoungyoung Kim
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, 222-1 wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Woo Seok Choi
- Department of Statistics, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Eun Jin Jang
- Department of Information Statistics, Andong National University, 1375, Gyeongdong-ro, Andong-si, Gyeongsangbuk-do, 36729, Republic of Korea
| | - Yoon-Kyoung Sung
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, 222-1 wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea.
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29
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Choi WS, Choi JH, Oh J, Shin IS, Yang JS. Effects of Remote Monitoring of Blood Pressure in Management of Urban Hypertensive Patients: A Systematic Review and Meta-Analysis. Telemed J E Health 2019; 26:744-759. [PMID: 31532328 DOI: 10.1089/tmj.2019.0028] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Background: Remote home blood pressure monitoring (RBPM) has been shown as effective in managing hypertension in underserved areas. Effects on urban patients, who are more easily provided with high-quality medical services, are still unclear. We systematically review previously published randomized controlled trials on the effect of RBPM for urban hypertensive patients. Methods: We searched electronic databases for studies published in English up to October 2018. Studies comparing the use of RBPM to face-to-face care were included. Outcome measures were changes in office blood pressure (BP) and the rate of BP control. Results: We identified 1,433 potential references for screening, of which 27 were eligible for review. Substantial heterogeneity was evident for the investigated variables. A significant standardized mean difference (SMD) was observed for RBPM for systolic BP, but the effect size was small compared to face-to-face care and was clinically irrelevant in avoiding cardiovascular events (0.212, 95% confidence interval 0.148-0.275; p < 0.001). For diastolic BP, the SMD between the two groups was small (0.170, p < 0.001) and the effect of RBPM was irrelevant in preventing cardiovascular events. The effect on the rate of BP control was significantly high for the intervention group (relative risk: 1.136; p = 0.018). Conclusions: This review demonstrates that RBPM performed on urban hypertensive patients has limited value and seems not to be superior to ordinary care in avoidance of cardiovascular events. Further studies are needed to provide more reliable information about the effectiveness of RBPM in preventing hypertensive cardiovascular complications.
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Affiliation(s)
- Woo Seok Choi
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Keyu Internal Medicine Clinic, Daejeon, Republic of Korea
| | - Jin Hyuk Choi
- Department of Philosophy, University of Warwick, Coventry, United Kingdom
| | - Jiwon Oh
- College of Nursing, Chungnam National University, Daejeon, Republic of Korea
| | - In-Soo Shin
- Department of Education, Jeonju University, Jeonju, Republic of Korea
| | - Jae-Suk Yang
- Moon Soul Graduate School of Future Strategy, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
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30
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Jeong DG, Ju HI, Choi YG, Roh CJ, Woo S, Choi WS, Lee JS. Nanoscale heat transport through the hetero-interface of SrRuO 3 thin films. Nanotechnology 2019; 30:374001. [PMID: 31181544 DOI: 10.1088/1361-6528/ab280d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A SrRuO3 thin film has been widely used as a metal electrode in electronic devices based on transition metal oxides, and hence it is important to understand its thermal transport properties to minimize a thermal degradation problem during the device operation. Using the time-domain thermoreflectance measurement technique, we investigate the cross-plane thermal conductivity of the SrRuO3 thin films with a thickness variation from 1 μm to 8 nm. We find that the thermal conductivity is reduced from about 6 W m-1 K-1 for the 1 μm thick film to about 1.2 W m-1 K-1 for the 8 nm thick film, and attribute this behavior to the boundary scattering of thermal carriers which originally have the mean free path of about 20 nm in a bulk state. Also, we observe a clear dip behavior of the thermal conductivity in the intermediate thickness around 30 nm which suggests an existence of a strong scattering source other than the film boundary. We explain this result by considering an additional interfacial scattering at the tetragonal-orthorhombic phase boundary which is formed during the strain relaxation with an increase of the film thickness.
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Affiliation(s)
- D G Jeong
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
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31
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Kang KT, Park J, Suh D, Choi WS. Synergetic Behavior in 2D Layered Material/Complex Oxide Heterostructures. Adv Mater 2019; 31:e1803732. [PMID: 30589101 DOI: 10.1002/adma.201803732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 09/18/2018] [Indexed: 05/28/2023]
Abstract
The marriage between a 2D layered material (2DLM) and a complex transition metal oxide (TMO) results in a variety of physical and chemical phenomena that cannot be achieved in either material alone. Interesting recent discoveries in systems such as graphene/SrTiO3 , graphene/LaAlO3 /SrTiO3 , graphene/ferroelectric oxide, MoS2 /SrTiO3 , and FeSe/SrTiO3 heterostructures include voltage scaling in field-effect transistors, charge state coupling across an interface, quantum conductance probing of the electrochemical activity, novel memory functions based on charge traps, and greatly enhanced superconductivity. In this context, various properties and functionalities appearing in numerous different 2DLM/TMO heterostructure systems are reviewed. The results imply that the multidimensional heterostructure approach based on the disparate material systems leads to an entirely new platform for the study of condensed matter physics and materials science. The heterostructures are also highly relevant technologically as each constituent material is a promising candidate for next-generation optoelectronic devices.
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Affiliation(s)
- Kyeong Tae Kang
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Jeongmin Park
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Dongseok Suh
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
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32
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Kang KT, Roh CJ, Lim J, Min T, Lee JH, Lee K, Lee TY, Kang S, Seol D, Kim J, Ohta H, Khare A, Park S, Kim Y, Chae SC, Oh YS, Lee J, Yu J, Lee JS, Choi WS. A Room-Temperature Ferroelectric Ferromagnet in a 1D Tetrahedral Chain Network. Adv Mater 2019; 31:e1808104. [PMID: 31034128 DOI: 10.1002/adma.201808104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Ferroelectricity occurs in crystals with broken spatial inversion symmetry. In conventional perovskite oxides, concerted ionic displacements within a 3D network of transition-metal-oxygen polyhedra (MOx ) manifest spontaneous polarization. Meanwhile, some 2D networks of MOx foster geometric ferroelectricity with magnetism, owing to the distortion of the polyhedra. Because of the fundamentally different mechanism of ferroelectricity in a 2D network, one can further challenge an uncharted mechanism of ferroelectricity in a 1D channel of MOx and estimate its feasibility. Here, ferroelectricity and coupled ferromagnetism in a 1D FeO4 tetrahedral chain network of a brownmillerite SrFeO2.5 epitaxial thin film are presented. The result provides a new paradigm for designing low-dimensional MOx networks, which is expected to benefit the realization of macroscopic ferro-ordering materials including ferroelectric ferromagnets.
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Affiliation(s)
- Kyeong Tae Kang
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Chang Jae Roh
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Jinyoung Lim
- Department of Physics and Astronomy, Center for Theoretical Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Taewon Min
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Jun Han Lee
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Kyoungjun Lee
- Department of Physics Education, Seoul National University, Seoul, 08826, Republic of Korea
| | - Tae Yoon Lee
- Department of Physics Education, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seunghun Kang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Daehee Seol
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jiwoong Kim
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Hiromichi Ohta
- Research Institute for Electronic Science, Hokkaido University, Sapporo, 001-0020, Japan
| | - Amit Khare
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Yunseok Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Seung Chul Chae
- Department of Physics Education, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yoon Seok Oh
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Jaekwang Lee
- Department of Physics, Pusan National University, Busan, 46241, Republic of Korea
| | - Jaejun Yu
- Department of Physics and Astronomy, Center for Theoretical Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jong Seok Lee
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
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Kuk SK, Gopinath K, Singh RK, Kim TD, Lee Y, Choi WS, Lee JK, Park CB. NADH-Free Electroenzymatic Reduction of CO2 by Conductive Hydrogel-Conjugated Formate Dehydrogenase. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00127] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Su Keun Kuk
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 335 Science Road, Daejeon 305-701, Republic of Korea
| | - Krishnasamy Gopinath
- Department of Chemical Engineering, Konkuk University, 120 Neungdong-ro, Seoul 05029, Republic of Korea
| | - Raushan K. Singh
- Department of Chemical Engineering, Konkuk University, 120 Neungdong-ro, Seoul 05029, Republic of Korea
| | - Tae-Doo Kim
- Department of Chemical Engineering, Konkuk University, 120 Neungdong-ro, Seoul 05029, Republic of Korea
| | - Youngjun Lee
- Department of Chemical Engineering, Konkuk University, 120 Neungdong-ro, Seoul 05029, Republic of Korea
| | - Woo Seok Choi
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 335 Science Road, Daejeon 305-701, Republic of Korea
| | - Jung-Kul Lee
- Department of Chemical Engineering, Konkuk University, 120 Neungdong-ro, Seoul 05029, Republic of Korea
| | - Chan Beum Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 335 Science Road, Daejeon 305-701, Republic of Korea
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34
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Park JB, Choi WS, Chung TH, Lee SH, Kwak MK, Ha JS, Jeong T. Transfer printing of vertical-type microscale light-emitting diode array onto flexible substrate using biomimetic stamp. Opt Express 2019; 27:6832-6841. [PMID: 30876260 DOI: 10.1364/oe.27.006832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/16/2019] [Indexed: 06/09/2023]
Abstract
We report the transfer printing of GaN-based microscale vertical-type light-emitting diodes (μ-VLEDs) using a functional layer and a biomimetic stamp. An oxide-based functional layer is inserted onto the structure of a μ-VLED and used to separate the chip from the μ-VLED wafer by absorbing the pulse of a UV pulse laser during pick-up of the transfer printing process. Polydimethylsiloxane (PDMS)-based biomimetic stamps have been fabricated to mimic the gecko lizard cilia for improved adhesion and repeatability. The biomimetic stamp has an adhesion force of 25.6 N/cm2, which is 12 times the adhesion of a flat stamp; an adhesion force of 10 N/cm2 or more was maintained after 100,000 repeated adhesion tests. A flexible 10 × 10 prototype array on a polyimide substrate was fabricated, and its bending test results indicated that the strain effect on the forward voltage and the output power was less than 1%. The stable bending test results of the prototype indicate that μ-VLEDs using biomimetic stamps allow the necessary stability for practical transfer printing.
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Yoo TS, Lee SA, Roh C, Kang S, Seol D, Guan X, Bae JS, Kim J, Kim YM, Jeong HY, Jeong S, Mohamed AY, Cho DY, Jo JY, Park S, Wu T, Kim Y, Lee J, Choi WS. Ferroelectric Polarization Rotation in Order-Disorder-Type LiNbO 3 Thin Films. ACS Appl Mater Interfaces 2018; 10:41471-41478. [PMID: 30406659 DOI: 10.1021/acsami.8b12900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The direction of ferroelectric polarization is prescribed by the symmetry of the crystal structure. Therefore, rotation of the polarization direction is largely limited, despite the opportunity it offers in understanding important dielectric phenomena such as piezoelectric response near the morphotropic phase boundaries and practical applications such as ferroelectric memory. In this study, we report the observation of continuous rotation of ferroelectric polarization in order-disorder-type LiNbO3 thin films. The spontaneous polarization could be tilted from an out-of-plane to an in-plane direction in the thin film by controlling the Li vacancy concentration within the hexagonal lattice framework. Partial inclusion of monoclinic-like phase is attributed to the breaking of macroscopic inversion symmetry along different directions and the emergence of ferroelectric polarization along the in-plane direction.
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Affiliation(s)
| | | | - Changjae Roh
- Department of Physics and Photon Science , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
| | | | | | - Xinwei Guan
- Materials Science and Engineering , King Abdullah University of Science and Technology , Thuwal 23955-6900 , Saudi Arabia
| | - Jong-Seong Bae
- Busan Center , Korea Basic Science Institute , Busan 46742 , Korea
| | - Jiwoong Kim
- Department of Physics , Pusan National University , Busan 46241 , Korea
| | | | - Hu Young Jeong
- UNIST Central Research Facilities , Ulsan National Institute of Science and Technology , Ulsan 44919 , Korea
| | | | - Ahmed Yousef Mohamed
- IPIT & Department of Physics , Chonbuk National University , Jeonju 54896 , Korea
| | - Deok-Yong Cho
- IPIT & Department of Physics , Chonbuk National University , Jeonju 54896 , Korea
| | - Ji Young Jo
- School of Materials Science and Engineering , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
| | - Sungkyun Park
- Department of Physics , Pusan National University , Busan 46241 , Korea
| | - Tom Wu
- Materials Science and Engineering , King Abdullah University of Science and Technology , Thuwal 23955-6900 , Saudi Arabia
- School of Materials Science and Engineering , University of New South Wales , Sydney , NSW 2052 , Australia
| | | | - Jongseok Lee
- Department of Physics and Photon Science , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
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36
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Kim NI, Sa YJ, Yoo TS, Choi SR, Afzal RA, Choi T, Seo YS, Lee KS, Hwang JY, Choi WS, Joo SH, Park JY. Oxygen-deficient triple perovskites as highly active and durable bifunctional electrocatalysts for oxygen electrode reactions. Sci Adv 2018; 4:eaap9360. [PMID: 29951583 PMCID: PMC6018999 DOI: 10.1126/sciadv.aap9360] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 04/27/2018] [Indexed: 05/15/2023]
Abstract
Highly active and durable bifunctional oxygen electrocatalysts have been of pivotal importance for renewable energy conversion and storage devices, such as unitized regenerative fuel cells and metal-air batteries. Perovskite-based oxygen electrocatalysts have emerged as promising nonprecious metal bifunctional electrocatalysts, yet their catalytic activity and stability still remain to be improved. We report a high-performance oxygen electrocatalyst based on a triple perovskite, Nd1.5Ba1.5CoFeMnO9-δ (NBCFM), which shows superior activity and durability for oxygen electrode reactions to single and double perovskites. When hybridized with nitrogen-doped reduced graphene oxide (N-rGO), the resulting NBCFM/N-rGO catalyst shows further boosted bifunctional oxygen electrode activity (0.698 V), which surpasses that of Pt/C (0.801 V) and Ir/C (0.769 V) catalysts and which, among the perovskite-based electrocatalysts, is the best activity reported to date. The superior catalytic performances of NBCFM could be correlated to its oxygen defect-rich structure, lower charge transfer resistance, and smaller hybridization strength between O 2p and Co 3d orbitals.
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Affiliation(s)
- Nam-In Kim
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Young Jin Sa
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Tae Sup Yoo
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sung Ryul Choi
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Rana Arslan Afzal
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Taekjib Choi
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Young-Soo Seo
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Kug-Seung Lee
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Jun Yeon Hwang
- Carbon Composite Materials Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology Jeonbuk Branch, Jeonbuk 55324, Republic of Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sang Hoon Joo
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
- Corresponding author. (J.-Y.P.); (S.H.J.)
| | - Jun-Young Park
- Hybrid Materials Center, Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
- Corresponding author. (J.-Y.P.); (S.H.J.)
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Yoon M, Jo MR, Kim PH, Choi WS, Kang SI, Choi SG, Lee JH, Lee HC, Son KT, Mok JS. Total and Methyl Mercury Concentrations in Antarctic Toothfish (Dissostichus mawsoni): Health Risk Assessment. Bull Environ Contam Toxicol 2018; 100:748-753. [PMID: 29564485 DOI: 10.1007/s00128-018-2326-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 03/15/2018] [Indexed: 06/08/2023]
Abstract
The concentrations of total mercury (THg) in different organs of the Antarctic toothfish (Dissostichus mawsoni) collected from CCAMLR research blocks in Subarea 88.3 and Division 58.4.1 off the coast of Antarctica were determined. The results revealed THg concentrations of 0.165 ± 0.095 mg/kg (0.023-0.454 mg/kg, wet weight) in the Antarctic toothfish. In muscle, methyl mercury (MeHg) accounted for approximately 40% of the THg. In a comparison analysis, muscle and liver tended to bioaccumulate the highest levels of THg, and both THg and MeHg contents showed correlations with fish length and weight. Compared with international guidelines, fish contained 2.5-6.4% and 4.0-10.3% of the provisional tolerable weekly intake for THg recommended by the Joint FAO/WHO Expert Committee on Food Additives and the tolerable weekly intake for MeHg proposed by the European Food Safety Authority, respectively. These results suggest that consumption of the Antarctic toothfish presents no health risk to humans.
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Affiliation(s)
- Minchul Yoon
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Mi Ra Jo
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Poong Ho Kim
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Woo Seok Choi
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Sang In Kang
- Department of Seafood and Aquaculture Science/Institute of Marine Industry, Gyeongsang National University, Tongyeong, 53063, Republic of Korea
| | - Seok Gwan Choi
- Distant-Water Fisheries Resources Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Jong Hee Lee
- Distant-Water Fisheries Resources Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Hee Chung Lee
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea
| | - Kwang Tae Son
- South-East Sea Fisheries Research Institute, National Institute of Fisheries Science, Tongyeong, 53085, Republic of Korea
| | - Jong Soo Mok
- Food Safety and Processing Research Division, National Institute of Fisheries Science, Busan, 46083, Republic of Korea.
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Abstract
INTRODUCTION Sufficient infrastructure for information and communications technology (ICT) and a well-established policy are necessary factors for smooth implementation of telemedicine. However, despite these necessary conditions being met, there are situations where telemedicine still fails to be accepted as a system due to the low receptivity of stakeholders. In this study, we analyse stakeholders' resistance to an organization's implementation of telemedicine. Focusing on the physicians' interests, we propose a strategy to minimize conflicts and improve acceptance. METHODS The Delphi study involved 190 telemedicine professionals who were recommended by 485 telemedicine-related personnel in South Korea. RESULTS Out of 190 professionals, 60% of enrolled participants completed the final questionnaires. The stakeholders were categorized into four groups: policy-making officials, physicians, patients, and industrialists. Among these, the physicians were most opposed to the adoption of telemedicine. The main causes of such opposition were found to be the lack of a medical services delivery system and the threat of disruption for primary care clinics. Very little consensus was observed among the stakeholders, except on the following points: the need for expansion of the national health insurance budget by the government, and the need for enhancement of physicians' professional autonomy to facilitate smooth agreements. DISCUSSION Our analysis on the causes of the resistance to telemedicine, carried out with the groups mentioned above, has important implications for policy-makers deriving strategies to achieve an appropriate consensus.
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Affiliation(s)
- Woo Seok Choi
- 1 Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,2 Keyu Internal Medicine Clinic, Daejeon, Republic of Korea
| | - Joowoong Park
- 1 Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | | | - Jae-Suk Yang
- 1 Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
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39
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Lumpkins CY, Filippi MK, Nazir N, Pacheco CM, Hester CM, Daley SM, Choi WS, Daley CM. It's not just about recruitment: An exploratory look at tobacco education sessions to increase participation into smoking cessation programs among American Indians. ACTA ACUST UNITED AC 2018; 3:1-4. [PMID: 34095515 PMCID: PMC8174104 DOI: 10.15761/hec.1000137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
American Indians (AI) have the highest smoking rates and lowest quit rates of any racial/ethnic group in the U.S. Researchers and community members from the American Indian Health Research and Education Alliance (AIHREA) created and evaluated a culturally-tailored smoking cessation program, All Nations Breath of Life (ANBL) as a recruitment tool for smoking cessation programs among AI. To increase enrollment in ANBL, AI smokers were approached at cultural events and asked to attend a 30-minute educational session (in-person, n= 179; tele-video, n=97). Tele-video (30%) and in-person (9%) session participants were recruited into ANBL. Pre- and post-tests showed participants in both sessions demonstrated increased motivation and confidence to quit smoking but significant differences were present in both sessions (p < 0.0001). Results indicate that theoretically guided and culturally tailored education sessions are viable approaches to educate and recruit underserved populations into programs that promote smoking cessation.
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Affiliation(s)
- C Y Lumpkins
- Department of Family Medicine, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Center for American Indian Community Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | | | - N Nazir
- Center for American Indian Community Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Preventive Medicine & Public Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | | | - C M Hester
- Department of Family Medicine, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Center for American Indian Community Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - S M Daley
- Center for American Indian Studies, Johnson County Community College, Kansas City, KS, 66210, USA
| | - W S Choi
- Center for American Indian Community Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Preventive Medicine & Public Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - C M Daley
- Department of Family Medicine, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Center for American Indian Community Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Preventive Medicine & Public Health, University of Kansas Medical Center, Kansas City, KS, 66160, USA
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40
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Woo S, Lee SA, Mun H, Choi YG, Zhung CJ, Shin S, Lacotte M, David A, Prellier W, Park T, Kang WN, Lee JS, Kim SW, Choi WS. Enhanced magnetic and thermoelectric properties in epitaxial polycrystalline SrRuO 3 thin films. Nanoscale 2018; 10:4377-4384. [PMID: 29450417 DOI: 10.1039/c7nr09627e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Transition metal oxide thin films show versatile electric, magnetic, and thermal properties which can be tailored by deliberately introducing macroscopic grain boundaries via polycrystalline solids. In this study, we focus on the modification of magnetic and thermal transport properties by fabricating single- and polycrystalline epitaxial SrRuO3 thin films using pulsed laser epitaxy. Using the epitaxial stabilization technique with an atomically flat polycrystalline SrTiO3 substrate, an epitaxial polycrystalline SrRuO3 thin film with the crystalline quality of each grain comparable to that of its single-crystalline counterpart is realized. In particular, alleviated compressive strain near the grain boundaries due to coalescence is evidenced structurally, which induced the enhancement of ferromagnetic ordering of the polycrystalline epitaxial thin film. The structural variations associated with the grain boundaries further reduce the thermal conductivity without deteriorating the electronic transport, and lead to an enhanced thermoelectric efficiency in the epitaxial polycrystalline thin films, compared with their single-crystalline counterpart.
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Affiliation(s)
- Sungmin Woo
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea.
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41
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Khare A, Lee J, Park J, Kim GY, Choi SY, Katase T, Roh S, Yoo TS, Hwang J, Ohta H, Son J, Choi WS. Directing Oxygen Vacancy Channels in SrFeO 2.5 Epitaxial Thin Films. ACS Appl Mater Interfaces 2018; 10:4831-4837. [PMID: 29327588 DOI: 10.1021/acsami.7b17377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Transition-metal oxides (TMOs) with brownmillerite (BM) structures possess one-dimensional oxygen vacancy channels (OVCs), which play a key role in realizing high ionic conduction at low temperatures. The controllability of the vacancy channel orientation, thus, possesses a great potential for practical applications and would provide a better visualization of the diffusion pathways of ions in TMOs. In this study, the orientations of the OVCs in BM-SrFeO2.5 are stabilized along two crystallographic directions of the epitaxial thin films. The distinctively orientated phases are found to be highly stable and exhibit a considerable difference in their electronic structures and optical properties, which could be understood in terms of orbital anisotropy. The control of the OVC orientation further leads to modifications in the hydrogenation of the BM-SrFeO2.5 thin films. The results demonstrate a strong correlation between crystallographic orientations, electronic structures, and ionic motion in the BM structure.
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Affiliation(s)
- Amit Khare
- Department of Physics, Indian Institute of Science Education of Research (IISER) , Bhopal 462 066, India
| | - Jaekwang Lee
- Department of Physics, Pusan National University , Pusan 46241, Republic of Korea
| | - Jaeseoung Park
- Department of Materials Science and Engineering, Pohang University of Science and Technology , Pohang 37673, Republic of Korea
| | - Gi-Yeop Kim
- Materials Modeling and Characterization Department, Korea Institute of Materials Science , Changwon 51508, Republic of Korea
| | - Si-Young Choi
- Materials Modeling and Characterization Department, Korea Institute of Materials Science , Changwon 51508, Republic of Korea
| | - Takayoshi Katase
- Research Institute for Electronic Science, Hokkaido University , Sapporo 001-0020, Japan
| | | | | | | | - Hiromichi Ohta
- Research Institute for Electronic Science, Hokkaido University , Sapporo 001-0020, Japan
| | - Junwoo Son
- Department of Materials Science and Engineering, Pohang University of Science and Technology , Pohang 37673, Republic of Korea
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Lee JH, Choi WS, Jeen H, Lee HJ, Seo JH, Nam J, Yeom MS, Lee HN. Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites. Sci Rep 2017; 7:16066. [PMID: 29167490 PMCID: PMC5700177 DOI: 10.1038/s41598-017-16246-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 10/13/2017] [Indexed: 12/21/2022] Open
Abstract
The topotactic phase transition in SrCoOx (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO2.5, however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoOx is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.
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Affiliation(s)
- J H Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea.
| | - Woo Seok Choi
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.,Department of Physics, Sungkyunkwan University, Suwon, 440-746, Korea
| | - H Jeen
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.,Department of Physics, Pusan National University, Busan, 46241, Korea
| | - H-J Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - J H Seo
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - J Nam
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - M S Yeom
- Department of Applied Research and Network R&D, Center for Computational Science and Engineering, Division of National Supercomputing R&D, Korea Institute of Science and Technology Information (KISTI), 245 Daehak-ro, Daejeon, 34141, Republic of Korea.
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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43
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Khare A, Shin D, Yoo TS, Kim M, Kang TD, Lee J, Roh S, Jung IH, Hwang J, Kim SW, Noh TW, Ohta H, Choi WS. Topotactic Metal-Insulator Transition in Epitaxial SrFeO x Thin Films. Adv Mater 2017; 29. [PMID: 28758333 DOI: 10.1002/adma.201606566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Revised: 04/28/2017] [Indexed: 05/12/2023]
Abstract
Topotactic phase transformation enables structural transition without losing the crystalline symmetry of the parental phase and provides an effective platform for elucidating the redox reaction and oxygen diffusion within transition metal oxides. In addition, it enables tuning of the emergent physical properties of complex oxides, through strong interaction between the lattice and electronic degrees of freedom. In this communication, the electronic structure evolution of SrFeOx epitaxial thin films is identified in real-time, during the progress of reversible topotactic phase transformation. Using real-time optical spectroscopy, the phase transition between the two structurally distinct phases (i.e., brownmillerite and perovskite) is quantitatively monitored, and a pressure-temperature phase diagram of the topotactic transformation is constructed for the first time. The transformation at relatively low temperatures is attributed to a markedly small difference in Gibbs free energy compared to the known similar class of materials to date. This study highlights the phase stability and reversibility of SrFeOx thin films, which is highly relevant for energy and environmental applications exploiting the redox reactions.
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Affiliation(s)
- Amit Khare
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Dongwon Shin
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Tae Sup Yoo
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Minu Kim
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul National University, Seoul, 08826, South Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, South Korea
| | - Tae Dong Kang
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul National University, Seoul, 08826, South Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, South Korea
| | - Jaekwang Lee
- Department of Physics, Pusan National University, Busan, 46241, South Korea
| | - Seulki Roh
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - In-Ho Jung
- Department of Mining and Materials Engineering, McGill University, Montreal, QC, H3A 0C5, Canada
| | - Jungseek Hwang
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Sung Wng Kim
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Tae Won Noh
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul National University, Seoul, 08826, South Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, South Korea
| | - Hiromichi Ohta
- Research Institute for Electronic Science, Hokkaido University, Sapporo, 001-0020, Japan
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, South Korea
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44
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Ko JW, Choi WS, Kim J, Kuk SK, Lee SH, Park CB. Self-Assembled Peptide-Carbon Nitride Hydrogel as a Light-Responsive Scaffold Material. Biomacromolecules 2017; 18:3551-3556. [DOI: 10.1021/acs.biomac.7b00889] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Jong Wan Ko
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Woo Seok Choi
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Jinhyun Kim
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Su Keun Kuk
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Sahng Ha Lee
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Chan Beum Park
- Department of Materials Science
and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
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45
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Kang KT, Kang H, Park J, Suh D, Choi WS. Quantum Conductance Probing of Oxygen Vacancies in SrTiO 3 Epitaxial Thin Film using Graphene. Adv Mater 2017; 29:1700071. [PMID: 28301058 DOI: 10.1002/adma.201700071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/03/2017] [Indexed: 06/06/2023]
Abstract
Quantum Hall conductance in monolayer graphene on an epitaxial SrTiO3 (STO) thin film is studied to understand the role of oxygen vacancies in determining the dielectric properties of STO. As the gate-voltage sweep range is gradually increased in the device, systematic generation and annihilation of oxygen vacancies, evidenced from the hysteretic conductance behavior in the graphene, are observed. Furthermore, based on the experimentally observed linear scaling relation between the effective capacitance and the voltage sweep range, a simple model is constructed to manifest the relationship among the dielectric properties of STO with oxygen vacancies. The inherent quantum Hall conductance in graphene can be considered as a sensitive, robust, and noninvasive probe for understanding the electronic and ionic phenomena in complex transition-metal oxides without impairing the oxide layer underneath.
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Affiliation(s)
- Kyeong Tae Kang
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Suwon, 16419, Korea
| | - Haeyong Kang
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Jeongmin Park
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Suwon, 16419, Korea
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Dongseok Suh
- Department of Energy Sciences, Sungkyunkwan University, Suwon, 16419, Korea
| | - Woo Seok Choi
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Korea
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Kim K, Lee BI, Chung YJ, Choi WS, Park CB. Alzheimer's Disease: Hematite-Based Photoelectrode Materials for Photoelectrocatalytic Inhibition of Alzheimer's β-Amyloid Self-Assembly (Adv. Healthcare Mater. 8/2017). Adv Healthc Mater 2017. [DOI: 10.1002/adhm.201770037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kayoung Kim
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Byung Il Lee
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - You Jung Chung
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Woo Seok Choi
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Chan Beum Park
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
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Kim K, Lee BI, Chung YJ, Choi WS, Park CB. Hematite-Based Photoelectrode Materials for Photoelectrocatalytic Inhibition of Alzheimer's β-Amyloid Self-Assembly. Adv Healthc Mater 2017; 6. [PMID: 28194907 DOI: 10.1002/adhm.201601133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 12/22/2016] [Indexed: 01/24/2023]
Abstract
A visible light-active, hematite-based photoelectrode platform for suppressing β-amyloid (Aβ) self-assembly in vitro is reported. Upon illumination of a light-emitting diode with an anodic bias, the hematite photoanode generates reactive radical species, such as superoxide ions and hydroxyl radicals, via photoelectrocatalytic process. According to our analyses, the hematite photoanode exhibited a strong inhibitory effect on Aβ aggregation under visible light illumination and anodic bias. We found that hole-derived radicals played a significant role of oxidizing Aβ peptides, which effectively blocked further aggregation. The efficacy of photoelectrocatalytic inhibition on Aβ aggregation was enhanced by introducing cobalt phosphate (Co-Pi) as a co-catalyst on the hematite photoanode, which facilitated the separation of electron-hole pairs. We verified that both bare and Co-Pi@hematite photoanodes are biocompatible and effective in reducing Aβ aggregation-induced cytotoxicity.
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Affiliation(s)
- Kayoung Kim
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Byung Il Lee
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - You Jung Chung
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Woo Seok Choi
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
| | - Chan Beum Park
- Department of Materials Science and Engineering; Korea Advanced Institute of Science and Technology (KAIST); 335 Science Road Yuseong-gu Daejeon 305-701 Republic of Korea
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48
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Abstract
Growth of perovskite oxide thin films on Si in crystalline form has long been a critical obstacle for the integration of multifunctional oxides into Si-based technologies. In this study, we propose pulsed laser deposition of a crystalline SrTiO3 thin film on a Si using graphene substrate. The SrTiO3 thin film on graphene has a highly (00l)-oriented crystalline structure which results from the partial epitaxy. Moreover, graphene promotes a sharp interface by highly suppressing the chemical intermixing. The important role of graphene as a 2D substrate and diffusion barrier allows the expansion of device applications based on functional complex oxides.
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Affiliation(s)
| | - Jae-Yeol Hwang
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS) , Suwon 16419, Korea
| | - Eun Sung Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS) , Suwon 16419, Korea
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Kim CJ, Choi WS, Jung Y, Kiem S, Seol HY, Woo HJ, Choi YH, Son JS, Kim KH, Kim YS, Kim ES, Park SH, Yoon JH, Choi SM, Lee H, Oh WS, Choi SY, Kim NJ, Choi JP, Park SY, Kim J, Jeong SJ, Lee KS, Jang HC, Rhee JY, Kim BN, Bang JH, Lee JH, Park S, Kim HY, Choi JK, Wi YM, Choi HJ. Surveillance of the Middle East respiratory syndrome (MERS) coronavirus (CoV) infection in healthcare workers after contact with confirmed MERS patients: incidence and risk factors of MERS-CoV seropositivity. Clin Microbiol Infect 2016; 22:880-886. [PMID: 27475739 PMCID: PMC7128923 DOI: 10.1016/j.cmi.2016.07.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/11/2016] [Accepted: 07/16/2016] [Indexed: 01/16/2023]
Abstract
Given the mode of transmission of Middle East respiratory syndrome (MERS), healthcare workers (HCWs) in contact with MERS patients are expected to be at risk of MERS infections. We evaluated the prevalence of MERS coronavirus (CoV) immunoglobulin (Ig) G in HCWs exposed to MERS patients and calculated the incidence of MERS-affected cases in HCWs. We enrolled HCWs from hospitals where confirmed MERS patients had visited. Serum was collected 4 to 6 weeks after the last contact with a confirmed MERS patient. We performed an enzyme-linked immunosorbent assay (ELISA) to screen for the presence of MERS-CoV IgG and an indirect immunofluorescence test (IIFT) to confirm MERS-CoV IgG. We used a questionnaire to collect information regarding the exposure. We calculated the incidence of MERS-affected cases by dividing the sum of PCR-confirmed and serology-confirmed cases by the number of exposed HCWs in participating hospitals. In total, 1169 HCWs in 31 hospitals had contact with 114 MERS patients, and among the HCWs, 15 were PCR-confirmed MERS cases in study hospitals. Serologic analysis was performed for 737 participants. ELISA was positive in five participants and borderline for seven. IIFT was positive for two (0.3%) of these 12 participants. Among the participants who did not use appropriate personal protective equipment (PPE), seropositivity was 0.7% (2/294) compared to 0% (0/443) in cases with appropriate PPE use. The incidence of MERS infection in HCWs was 1.5% (17/1169). The seroprevalence of MERS-CoV IgG among HCWs was higher among participants who did not use appropriate PPE.
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Affiliation(s)
- C-J Kim
- Department of Internal Medicine, Division of Infectious Diseases, Ewha Womans University School of Medicine, South Korea
| | - W S Choi
- Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea
| | - Y Jung
- Department of Internal Medicine, Konyang University Hospital, South Korea
| | - S Kiem
- Department of Internal Medicine, Inje University Haeundae Paik Hospital, South Korea
| | - H Y Seol
- Department of Internal Medicine, Good GangAn Hospital, South Korea
| | - H J Woo
- Department of Internal Medicine, Hallym University Dongtan Sacred Heart Hospital, South Korea
| | - Y H Choi
- Department of Internal Medicine, Ajou University Hospital, South Korea
| | - J S Son
- Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, South Korea
| | - K-H Kim
- Department of Internal Medicine, Pusan National University Hospital, South Korea
| | - Y-S Kim
- Division of Infectious Diseases, Department of Internal Medicine, Chungnam National University School of Medicine, South Korea
| | - E S Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, South Korea
| | - S H Park
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Daejeon St. Mary's Hospital, South Korea
| | - J H Yoon
- Department of Internal Medicine, Eulji University Hospital, South Korea
| | - S-M Choi
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Yeouido St. Mary's Hospital, South Korea
| | - H Lee
- Division of Infectious Diseases, Dong-A University Hospital, South Korea
| | - W S Oh
- Department of Internal Medicine, Kangwon National University Hospital, South Korea
| | - S-Y Choi
- Department of Neurology, Dae Cheong Hospital, South Korea
| | - N-J Kim
- Department of Internal Medicine, Seoul National University Hospital, South Korea
| | - J-P Choi
- Department of Internal Medicine, Seoul Medical Center, South Korea
| | - S Y Park
- Department of Internal Medicine, Hallym University Kangdong Sacred Heart Hospital, South Korea
| | - J Kim
- Department of Internal Medicine, Hanyang University Guri Hospital, South Korea
| | - S J Jeong
- Department of Internal Medicine, Gangnam Severance Hospital, South Korea
| | - K S Lee
- Department of Internal Medicine, Myongji Hospital, South Korea
| | - H C Jang
- Department of Internal Medicine, Chonnam National University Hospital, South Korea
| | - J Y Rhee
- Department of Internal Medicine, Dankook University Hospital, South Korea
| | - B-N Kim
- Department of Internal Medicine, Inje University Sanggye Paik Hospital, South Korea
| | - J H Bang
- Department of Internal Medicine, Borame Medical Center, South Korea
| | - J H Lee
- Department of Internal Medicine, Wonkwang University Hospital, South Korea
| | - S Park
- Department of Family Medicine, Seobuk Hospital Seoul Metropolitan Government, South Korea
| | - H Y Kim
- Department of Internal Medicine, Wonju Severance Christian Hospital, South Korea
| | - J K Choi
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Bucheon St. Mary's Hospital, South Korea
| | - Y-M Wi
- Department of Internal Medicine, Samsung Changwon Hospital, South Korea
| | - H J Choi
- Department of Internal Medicine, Division of Infectious Diseases, Ewha Womans University School of Medicine, South Korea.
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50
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Abstract
Human urine is considered as an alternative source of hydrogen and electricity owing to its abundance and high energy density. Here we show the utility of human urine as a chemical fuel for driving redox biocatalysis in a photoelectrochemical cell. Ni(OH)2 -modified α-Fe2 O3 is selected as a photoanode for the oxidation of urea in human urine and black silicon (bSi) is used as a photocathode material for nicotinamide cofactor (NADH: hydrogenated nicotinamide adenine dinucleotide) regeneration. The electrons extracted from human urine are used for the regeneration of NADH, an essential hydride mediator that is required for numerous redox biocatalytic reactions. The catalytic reactions at both the photoanode and the photocathode were significantly enhanced by light energy that lowered the overpotential and generated high currents in the full cell system.
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Affiliation(s)
- Woo Seok Choi
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 305-701, Republic of Korea
| | - Sahng Ha Lee
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 305-701, Republic of Korea
| | - Jong Wan Ko
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 305-701, Republic of Korea
| | - Chan Beum Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 305-701, Republic of Korea.
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