106 results on '"Lee, Sanghun"'
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2. A 32-Gb/s Single-Ended PAM-4 Transceiver With Asymmetric Termination and Equalization Techniques for Next-Generation Memory Interfaces
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Kim, Hyuntae, Jo, Yunseong, Lee, Sanghun, Lee, Eunsang, Choi, Young, Park, Jaewoo, Kwak, Myoungbo, Choi, Jung-Hwan, Choi, Youngdon, and Han, Jaeduk
- Abstract
This paper presents a high-speed single-ended 4-level pulse amplitude modulation (PAM-4) transceiver for next-generation memory interfaces, achieving a data rate of 32Gb/s. The proposed asymmetrically terminated PAM-4 driver is optimized for pseudo open drain (POD) channel configurations and improves signal-to-noise ratio (SNR) with a larger output swing. The dynamic logic-based high-speed 4-to-1 serializer enhances the transmitter output’s jitter characteristic by avoiding high-frequency components in the selection signals. The 4-tap feed-forward equalizer (FFE) with two operation modes and one sliding tap flexibly compensates for inter-symbol interference (ISI) of the channel. In the receiver frontend, a continuous-time linear equalizer (CTLE), which utilizes a trans-admittance stage (TAS) and a trans-impedance amplifier (TIA) with an inductive load, provides high-frequency boosting and robust single-to-differential conversion performance through the design techniques of current source gain-boosting and capacitive compensation. The low kickback noise comparators mitigate clock feedthrough and noise coupling during multi-phase PAM-4 sampling and embed the 1-tap PAM-4 decision feedback equalizer (DFE) operation by directly feeding back the previous sampling phase’s outputs. The transceiver prototype fabricated in 28-nm CMOS technology occupies 0.126 mm2. At 32 Gb/s, a bit error rate of under
$10^{-12}$ - Published
- 2024
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3. Size-Controllable and Monodispersed Lipid Nanoparticle Production with High mRNA Delivery Efficiency Using 3D-Printed Ring Micromixers
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Hong, Jiwoo, Lee, Sanghun, Park, Hyochan, Ahn, Daehyeon, Lee, Jung Min, Choe, Hyeongju, Kim, Donghoon, Kim, Ju Hee, and Chon, Chan Hee
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Lipid nanoparticles (LNPs) are gaining recognition as potentially effective carriers for delivery of therapeutic agents, including nucleic acids (DNA and RNA), for the prevention and treatment of various diseases. Much effort has been devoted to the implementation of microfluidic techniques for the production of monodisperse and stable LNPs and the improvement of encapsulation efficiency. Here, we developed three-dimensional (3D)-printed ring micromixers for the production of size-controllable and monodispersed LNPs with a high mRNA delivery efficiency. The effects of flow rate and ring shape asymmetry on the mixing performance were initially examined. Furthermore, the physicochemical properties (such as hydrodynamic diameter, polydispersity, and encapsulation efficiency) of the generated LNPs were quantified as a function of these physical parameters via biochemical analysis and cryo-electron microscopy imaging. With a high production rate of 68 mL/min, our 3D-printed ring micromixers can be used to manufacture LNPs with diameters less than 90 nm, low polydispersity (<0.2), and high mRNA encapsulation efficiency (>91%). Despite the simplicity of the ring-shaped mixer structure, we can produce mRNA-loaded LNPs with exceptional quality and high throughput, outperforming costly commercial micromixers.
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- 2024
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4. On the effect heterogeneity of established disease susceptibility loci for Alzheimer's disease across different genetic ancestries.
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Lee, Sanghun, Hecker, Julian, Hahn, Georg, Mullin, Kristina, Lutz, Sharon M., Tanzi, Rudolph E., Lange, Christoph, and Prokopenko, Dmitry
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INTRODUCTION: Genome‐wide association studies have identified numerous disease susceptibility loci (DSLs) for Alzheimer's disease (AD). However, only a limited number of studies have investigated the dependence of the genetic effect size of established DSLs on genetic ancestry. METHODS: We utilized the whole genome sequencing data from the Alzheimer's Disease Sequencing Project (ADSP) including 35,569 participants. A total of 25,459 subjects in four distinct populations (African ancestry, non‐Hispanic White, admixed Hispanic, and Asian) were analyzed. RESULTS: We found that nine DSLs showed significant heterogeneity across populations. Single nucleotide polymorphism (SNP) rs2075650 in translocase of outer mitochondrial membrane 40 (TOMM40) showed the largest heterogeneity (Cochran's Q = 0.00, I2 = 90.08), followed by other SNPs in apolipoprotein C1 (APOC1) and apolipoprotein E (APOE). Two additional loci, signal‐induced proliferation‐associated 1 like 2 (SIPA1L2) and solute carrier 24 member 4 (SLC24A4), showed significant heterogeneity across populations. DISCUSSION: We observed substantial heterogeneity for the APOE‐harboring 19q13.32 region with TOMM40/APOE/APOC1 genes. The largest risk effect was seen among African Americans, while Asians showed a surprisingly small risk effect. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Pinuseldarone, a Clerodane-Type Diterpene from Pinus eldarica Needles and Phytochemicals as Novel Agents for Regulating Brown Adipogenesis and Thermogenesis.
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Cho, Yeo Rang, Lee, Sanghun, Kim, Hyoju, Park, Eon Chung, Jeong, Se Yun, Hamishehkar, Hamed, Jung, Su Myung, and Kim, Ki Hyun
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- 2024
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6. Melting of Unidirectional Charge Density Waves across Twin Domain Boundaries in GdTe3.
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Lee, Sanghun, Kim, Eunseo, Bang, Junho, Park, Jongho, Kim, Changyoung, Wulferding, Dirk, and Cho, Doohee
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- 2023
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7. Development of Deep Learning Color Recognition Model for Color Measurement Processes
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Lee, Sanghun, Kim, Ki-Sub, and Kang, Jeong Won
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We present a deep learning color recognition model for the color measurement process in the paint industry. Currently, spectrophotometers are primarily used for color measurements owing to their accuracy. The measurement method involves manually injecting the sample into a spectrophotometer. Our proposed method uses a webcam with a deep learning model on the stand of a spectrophotometer. Deep learning models are widely used for image and color detection. In this study, the “you only look once (YOLO)” algorithm is applied for real-time detection of color samples. Upon training various sample images using YOLO, the model could detect the sample area in real time using a webcam. An open source computer vision (OpenCV) library was used for the color recognition model, and the detected RGB color value was converted to the international commission on illumination color space (CIELAB) value, which is primarily used in the color measuring process. However, because of the mirror-like reflection of light from a surface with specular reflection, it is difficult to implement the color value using a camera. To address this problem, we compare several specular removal methods and propose the most suitable model for the color recognition model of color samples. The accuracy of the proposed model was verified by comparing the colors of various samples. Our proposed approach can easily detect samples and color values, which can contribute significantly to automatically calculating the exact amount of coloring required for the target color.
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- 2024
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8. Evaluation of Electrolyte Materials of Gd- and Ce-Doped Scandia-Stabilized Zirconia and Yb- and Bi-Doped Gadolinium-Doped Ceria for Highly Durable Solid Oxide Fuel Cells
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Lee, Sanghun, Lee, Kunho, Lee, Jaemyung, Lee, Jaeseok, Kim, Taehong, and Bae, Joongmyeon
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Solid oxide fuel cells (SOFCs) have attracted significant attention as a highly efficient type of fuel cell. Recent research proposes the use of co-doped scandium-stabilized zirconia with Gd and Ce (denoted as 10Sc0.5Gd0.5CeSZ) and Yb and Bi co-doped gadolinium-doped ceria (denoted as GYBC) as promising materials for the electrolyte and buffer layers, respectively. 10Sc0.5Gd0.5CeSZ exhibits excellent structural stability and ionic conductivity, which can be attributed to the doping of Ce for enhanced stability and Gd for improved ionic conductivity. On the other hand, GYBC demonstrates good sinterability and ionic conductivity due to the ability of Bi to lower the sintering temperature and the high ionic conductivity of Yb. To evaluate the feasibility of 10Sc0.5Gd0.5CeSZ and GYBC at the single cell level. X-ray diffraction (XRD) peaks and Rietveld refinements show good structural stability with slight increase in the lattice parameter by doping. The particle morphologies, size distributions, and BET surface areas are evaluated for the basic material characterizations. Then, lanthanum strontium cobalt ferrite (LSCF)–gadolinium-doped ceria (GDC) was selected as cathode material with 10Sc0.5Gd0.5CeSZ and GYBC. Finally, a single cell composed of Ni-Yttria stabilized zirconia (YSZ)/10Sc0.5Gd0.5CeSZ/GYBC/LSCF-GDC (6.5:3.5) is fabricated by sequential 3-layer co-tape casting technique, and it shows good open circuit voltage of > 1.0 V, high electrochemical performance of 0.73 W/cm2and low ohmic resistance of 0.17 Ωcm2at 750 °C. Then, the electrochemical characteristics and long-term durability of this single cell are evaluated over 500 h without degradation issues. Based on these results, it is concluded that 10Sc0.5Gd0.5CeSZ and GYBC are promising candidate materials for SOFCs.
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- 2024
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9. A PSRR-Enhanced Fast-Response Inverter-Based LDO for Mobile Devices
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Lee, Sanghun, Lim, Jaemyung, and Han, Jaeduk
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A low-dropout (LDO) regulator controlled by an inverter-based amplifier is proposed to accomplish the latest processor power requirements. The proposed inverter-based amplifier provides a high DC gain in low-voltage operation. Furthermore, an auxiliary non-inverting amplifier is adopted to regulate the wider output voltage and enhance power supply rejection ratio (PSRR) performance. The proposed LDO regulator has been implemented in a 28-nm CMOS process and provides an output range of 0.2–1.05 V from the input range of 0.4–1.1 V. With the input voltage of 1 V, the settling time is within 71.8 ns for 50-mV overshoot and 63 ns for 47-mV undershoot. With the low input voltage of 600 mV, the settling time is within 269 ns for 81-mV overshoot and 182 ns for 84-mV undershoot. The measured values of PSRR are 44.3 dB and 25.0 dB at 100 kHz and 10 MHz at 1-V input voltage, respectively. The PSRR with 600-mV input voltage shows 30 dB up to 600 kHz.
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- 2024
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10. A paintable and adhesive hydrogel cardiac patch with sustained release of ANGPTL4 for infarcted heart repair
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Lee, Mingyu, Kim, Yong Sook, Park, Junggeon, Choe, Goeun, Lee, Sanghun, Kang, Bo Gyeong, Jun, Ju Hee, Shin, Yoonmin, Kim, Minchul, Ahn, Youngkeun, and Lee, Jae Young
- Abstract
The infarcted heart undergoes irreversible pathological remodeling after reperfusion involving left ventricle dilation and excessive inflammatory reactions in the infarcted heart, frequently leading to fatal functional damage. Extensive attempts have been made to attenuate pathological remodeling in infarcted hearts using cardiac patches and anti-inflammatory drug delivery. In this study, we developed a paintable and adhesive hydrogel patch using dextran-aldehyde (dex-ald) and gelatin, incorporating the anti-inflammatory protein, ANGPTL4, into the hydrogel for sustained release directly to the infarcted heart to alleviate inflammation. We optimized the material composition, including polymer concentration and molecular weight, to achieve a paintable, adhesive hydrogel using 10% gelatin and 5% dex-ald, which displayed in-situ gel formation within 135 s, cardiac tissue-like modulus (40.5 kPa), suitable tissue adhesiveness (4.3 kPa), and excellent mechanical stability. ANGPTL4 was continuously released from the gelatin/dex-ald hydrogel without substantial burst release. The gelatin/dex-ald hydrogel could be conveniently painted onto the beating heart and degraded in vivo. Moreover, in vivo studies using animal models of acute myocardial infarction revealed that our hydrogel cardiac patch containing ANGPTL4 significantly improved heart tissue repair, evaluated by echocardiography and histological evaluation. The heart tissues treated with ANGPTL4-loaded hydrogel patches exhibited increased vascularization, reduced inflammatory macrophages, and structural maturation of cardiac cells. Our novel hydrogel system, which allows for facile paintability, appropriate tissue adhesiveness, and sustained release of anti-inflammatory drugs, will serve as an effective platform for the repair of various tissues, including heart, muscle, and cartilage.
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- 2024
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11. Melting of Unidirectional Charge Density Waves across Twin Domain Boundaries in GdTe3
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Lee, Sanghun, Kim, Eunseo, Bang, Junho, Park, Jongho, Kim, Changyoung, Wulferding, Dirk, and Cho, Doohee
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Solids undergoing a transition from order to disorder experience a proliferation of topological defects. The melting process generates transient quantum states. However, their dynamic nature with a femtosecond lifetime hinders exploration with atomic precision. Here, we suggest an alternative approach to the dynamic melting process by focusing on the interface created by competing degenerate quantum states. We use a scanning tunneling microscope (STM) to visualize the unidirectional charge density wave (CDW) and its spatial progression (“static melting”) across a twin domain boundary (TDB) in the layered material GdTe3. Combining the STM with a spatial lock-in technique, we reveal that the order parameter amplitude attenuates with the formation of dislocations and thus two different unidirectional CDWs coexist near the TDB, reducing the CDW anisotropy. Notably, we discovered a correlation between this anisotropy and the CDW gap. Our study provides valuable insight into the behavior of topological defects and transient quantum states.
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- 2023
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12. Implantable polypyrrole bioelectrodes inducing anti-inflammatory macrophage polarization for long-term in vivo signal recording.
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Lee, Sanghun, Park, Sehyeon, Park, Junggeon, and Lee, Jae Young
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ELECTRODE performance ,MACROPHAGES ,ELECTRONIC equipment ,ARTIFICIAL implants ,POLYPYRROLE ,HEPARIN ,MEDICAL equipment ,MICROBIAL fuel cells - Abstract
Bioelectrodes are critical components of implantable electronic devices that enable precise electrical signal transmission in close contact with living tissues. However, their in vivo performance is often compromised by inflammatory tissue reactions mainly induced by macrophages. Hence, we aimed to develop implantable bioelectrodes with high performance and high biocompatibility by actively modulating the inflammatory response of macrophages. Consequently, we fabricated heparin-doped polypyrrole electrodes (PPy/Hep) and immobilized anti-inflammatory cytokines (interleukin-4 [IL-4]) via non-covalent interactions. IL-4 immobilization did not alter the electrochemical performance of the original PPy/Hep electrodes. In vitro primary macrophage culture revealed that IL-4-immobilized PPy/Hep electrodes induced anti-inflammatory polarization of macrophages, similar to the soluble IL-4 control. In vivo subcutaneous implantation indicated that IL-4 immobilization on PPy/Hep promoted the anti-inflammatory polarization of host macrophages and significantly mitigated scarring around the implanted electrodes. In addition, high-sensitivity electrocardiogram signals were recorded from the implanted IL-4-immobilized PPy/Hep electrodes and compared to bare gold and PPy/Hep electrodes, which were maintained for up to 15 days post-implantation. This simple and effective surface modification strategy for developing immune-compatible bioelectrodes will facilitate the development of various electronic medical devices that require high sensitivities and long-term stabilities. To fabricate highly immunocompatible conductive polymer-based implantable electrodes with high performance and stability in vivo , we introduced the anti-inflammatory activity to PPy/Hep electrodes by immobilizing IL-4 via non-covalent surface modification. IL-4-immobilized PPy/Hep could significantly mitigate inflammatory responses and scarring around implants by skewing macrophages to an anti-inflammatory phenotype. The IL-4-immobilized PPy/Hep electrodes could successfully record in vivo electrocardiogram signals for up to 15 days with no substantial sensitivity loss, retaining their superior sensitivity compared to bare gold and pristine PPy/Hep electrodes. Our simple and effective surface modification strategy for developing immune-compatible bioelectrodes will facilitate the development of various electronic medical devices that require high sensitivities and long-term stabilities, such as neural electrode arrays, biosensors, and cochlear electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2023
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13. A Conductive and Adhesive Hydrogel Composed of MXene Nanoflakes as a Paintable Cardiac Patch for Infarcted Heart Repair.
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Lee, Mingyu, Park, Junggeon, Choe, Goeun, Lee, Sanghun, Kang, Bo Gyeong, Jun, Ju Hee, Shin, Yoonmin, Kim, Min Chul, Kim, Yong Sook, Ahn, Youngkeun, and Lee, Jae Young
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- 2023
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14. Fine-Tuned Synthesis for Reducing Residual Lithium in Ni-Rich Cathode Materials for Lithium-Ion Batteries.
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Shim, Jae-Hyun, Jung, Min-Hyoung, Yang, Min-Ji, Lee, Jaehan, Kim, In, Ahn, Young Ju, Kim, Young-Min, and Lee, Sanghun
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- 2023
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15. A Conductive and Adhesive Hydrogel Composed of MXene Nanoflakes as a Paintable Cardiac Patch for Infarcted Heart Repair
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Lee, Mingyu, Park, Junggeon, Choe, Goeun, Lee, Sanghun, Kang, Bo Gyeong, Jun, Ju Hee, Shin, Yoonmin, Kim, Min Chul, Kim, Yong Sook, Ahn, Youngkeun, and Lee, Jae Young
- Abstract
Myocardial infarction (MI) is a major cause of death worldwide. After the occurrence of MI, the heart frequently undergoes serious pathological remodeling, leading to excessive dilation, electrical disconnection between cardiac cells, and fatal functional damage. Hence, extensive efforts have been made to suppress pathological remodeling and promote the repair of the infarcted heart. In this study, we developed a hydrogel cardiac patch that can provide mechanical support, electrical conduction, and tissue adhesiveness to aid in the recovery of an infarcted heart function. Specifically, we developed a conductive and adhesive hydrogel (CAH) by combining the two-dimensional titanium carbide (Ti3C2Tx) MXene with natural biocompatible polymers [i.e., gelatin and dextran aldehyde (dex-ald)]. The CAH was formed within 250 s of mixing the precursor solution and could be painted. The hydrogel containing 3.0 mg/mL MXene, 10% gelatin, and 5% dex-ald exhibited appropriate material characteristics for cardiac patch applications, including a uniform distribution of MXene, a high electrical conductivity (18.3 mS/cm), cardiac tissue-like elasticity (30.4 kPa), strong tissue adhesion (6.8 kPa), and resistance to various mechanical deformations. The CAH was cytocompatible and induced cardiomyocyte (CM) maturation in vitro, as indicated by the upregulation of connexin 43 expression and a faster beating rate. Furthermore, CAH could be painted onto the heart tissue and remained stably adhered to the beating epicardium. In vivo animal studies revealed that CAH cardiac patch treatment significantly improved cardiac function and alleviated the pathological remodeling of an infarcted heart. Thus, we believe that our MXene-based CAH can potentially serve as a promising platform for the effective repair of various electroactive tissues including the heart, muscle, and nerve tissues.
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- 2023
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16. Improvements in Antineutrino Spectrum by Including Fission Product Corrections and Calculation of Scatter-Based Pulse Height Distributions
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Ang, Wei Eng, Lee, Sanghun, and Prasad, Shikha
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AbstractModeling a reactor’s antineutrino flux spectrum is a critical step in studying its detector response. The first objective of this paper is to study the importance of fission product libraries in the construction of the antineutrino spectrum using the summation method and with various other corrections, including excited states in fission products, finite size, weak magnetism, and radiative corrections. We have used the ENDF/B-VIII.0 and JEFF-3.3 nuclear libraries as our base data to model the antineutrino spectrum. We have also included the total absorption gamma spectroscopy (TAGS) data, which is free from the pandemonium effect, when such data are available. Our analysis includes the newest TAGS data sets from Gombas et al. [Phys. Rev. C, Vol. 103, p. 35803 (2021)] with additions made after the Estienne et al. [EPJ Web Conf., Vol. 211, p. 01001 (2019)] reactor antineutrino spectra study involving TAGS data. The excited state correction has the highest impact on the antineutrino energy spectra, increasing the values 29% to 37% on average in the energy range of 0.5 to 2 MeV. This antineutrino spectra correction also shows an increase of 4.71% to 7.13% in the range of 0 to 2 MeV, with improving excited states using the TAGS data from published literature. Next, antineutrino spectra including the excited state correction using the Gross Theory causes reduction by 11.56% to 69.46% for all four fissionable isotopes in the range of 6 to 8 MeV. The finite size correction, radiative correction, and weak magnetism corrections cause no more than a 3.27% difference between the corrected and uncorrected spectra. We studied the impact of various corrections to the antineutrino spectra and quantified the improvements made in the antineutrino spectrum calculation due to these changes. However, we have not included forbidden decays to simplify the calculations.The second objective of this work is to determine the impact of spectrum improvements on the coherent-elastic-neutrino-nucleus-scatter (CEνNS)-based detector response because this detection mechanism is more sensitive to lower energy antineutrinos, as expected from a nuclear reactor. We calculate pulse height distributions of Ge- and Si-based CEνNS sensors assuming a 20-eV nuclear recoil threshold. Toward this objective, we formulate pulse height distribution probabilities for different incident antineutrino energies in Ge and Si for a 100-kg detector placed 10 m away from the 1-MW TRIGA reactor with a 20-eV nuclear recoil energy threshold. Our results show that the reaction rate with corrected spectra for a CEνNS-based natural Ge detector is 20.6 events/day and a natural Si detector is 7.18 events/day. The biggest impact on the reaction rates between 38% and 41% is observed due to the excited state corrections. To benchmark our results, we show excellent agreement with the previous antineutrino spectrum calculated by Huber [Phys. Rev. C, Vo. 84, p. 24617 (2011)] and Hayes et al. [Phys. Rev. Lett., Vol. 112, p. 202501 (2014)].
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- 2023
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17. Excited-State Modification of Phenylimidazole-Based Cyclometalated Ir(III) Complexes through Secondary Bulky Aryl Substitution and Inductive Modification Enhances the Blue Emission Efficiency in Phosphorescent OLEDs.
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Kim, So-Yoen, Kim, Jin-Hyoung, Lee, Sanghun, Yun, Bo-Sun, Son, Ho-Jin, and Kang, Sang Ook
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- 2022
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18. Development of a Signal Processing Software for Scintillation Detectors and Implementation on an FPGA for Fast Sensing
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Wellons, Benjamin, Kumaran, Rishya Sankar, Lee, Sanghun, and Prasad, Shikha
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AbstractAn open-source code RadSigPro 1.0 has been developed and used for fast processing of nanosecond-long pulses from scintillation detectors. This processing includes pulse height distribution (PHD), pulse shape discrimination (PSD), and time of flight (TOF). The code has been implemented onto the programmable logic design of a field programmable gate array (FPGA) design for on-the-fly processing of neutron and gamma-ray pulses. A weighted average of the percent difference of the results for RadSigPro 1.0 implemented on a CPU and a FPGA logic design is calculated. This shows a 0% difference for the PHD data sets, a 0.458% and 0.344% difference for the designated gamma detector and neutron detector PSD data sets, respectively, and a 0% difference for the TOF data set. When the FPGA logic design is applied and simulated, it computed the total and tail pulse areas within 5 ns of the arrival of the final data point used for accumulation and also captured the pulse height value within 2 ns of the arrival of the pulse’s maximum data point.
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- 2023
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19. Synthesis and Characterization of Blue Phosphorescent NHC-Ir(III) Complexes with Annulated Heterocyclic 1,2,4-Triazolophenanthridine Derivatives for Highly Efficient PhOLEDs.
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Yun, Bo-Sun, Kim, So-Yoen, Kim, Jin-Hyoung, Choi, Sunghan, Lee, Sanghun, Son, Ho-Jin, and Kang, Sang Ook
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- 2022
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20. Excited-State Modification of Phenylimidazole-Based Cyclometalated Ir(III) Complexes through Secondary Bulky Aryl Substitution and Inductive Modification Enhances the Blue Emission Efficiency in Phosphorescent OLEDs
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Kim, So-Yoen, Kim, Jin-Hyoung, Lee, Sanghun, Yun, Bo-Sun, Son, Ho-Jin, and Kang, Sang Ook
- Abstract
To elucidate the key parameters governing the emission properties of phenylimidazole (pim)-based Ir(III) emitters, including their electronic structure and the bulky aryl substitution effect, a series of pim-based iridium(III) complexes (Ir(Rpim-X)3, Rpim-X= 1-R-2-(X-phenyl)-1H-imidazole) bearing secondary pendants of increasing bulkiness [R = methyl (Me), phenyl (Ph), terphenyl (TPh), or 4-isopropyl terphenyl (ITPh)] and three different primary pim ligands (X = F, F2, and CN) were designed and synthesized. Based on photophysical and electrochemical analyses, it was found that the excited state properties are highly dependent on the bulkiness of the secondary substituent and the inductive nature of the primary pim ligand. The incorporation of bulky TPh/ITPh substituents in the second coordination sphere significantly enhanced the emission efficiencies in the solid state (ΦPL= 72.1–84.9%) compared to those of the methyl- or phenyl-substituted Ir(III) complexes (ΦPL= 30.4% for Ir(Mepim)3and 63.7% for Ir(Phpim)3). Further modification of the secondary aryl substituent (Ir(TPhpim)3→ Ir(ITPhpim)3) through the incorporation of an isopropyl group and F substitution on the primary pim ligand (Ir(TPh/ITPhpim)3→ Ir(TPh/ITPhpim-F/F2)3) resulted in a slight decrease in the LUMO and a significant decrease in the HOMO energy levels, respectively; these energy level adjustments consequently amplified emission blue shifts, thereby enabling efficient blue electroluminescence in phosphorescent organic light-emitting diodes. Theoretical calculations revealed that the excited-state properties of pim-based Ir(III) complexes can be modulated by the nature of the peripheral substituent and the presence of an EWG substituent. Among the fabricated blue-emitting TPh/ITPh-substituted Ir(III) complexes, Ir(ITPhpim-F)3, Ir(TPhpim-F2)3, and Ir(ITPhpim-F2)3were tested as blue-emitting dopants for blue phosphorescent OLEDs owing to their high solid radiative quantum yields (ΦPL= 75.9–84.9%). The Ir(ITPhpim-F)3-doped multilayer device displayed the best performance with a maximum external quantum efficiency of 21.0%, a maximum current efficiency of 43.6 cd/A, and CIE coordinates of 0.18 and 0.31.
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- 2022
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21. Vulvar Reconstruction Using Keystone Flaps Based on the Perforators of Three Arteries
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Lee, Yunjae, Lee, Sanghun, Lee, Dongkyu, Yeo, Hyeonjung, Park, Hannara, and Park, Hyochun
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- 2022
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22. Tuning the Photophysical Properties of Homoleptic Tris-Cyclometalated Ir(III) Complexes by Facile Modification of the Imidazo-Phenanthridine and Their Application to Phosphorescent Organic Light-Emitting Diodes.
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Kim, So-Yoen, Kim, Jin-Hyoung, Lee, Sanghun, Yun, Bo-Sun, Son, Ho-Jin, and Kang, Sang Ook
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- 2022
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23. High-Performance Implantable Bioelectrodes with Immunocompatible Topography for Modulation of Macrophage Responses.
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Lee, Sanghun, Park, Junggeon, Kim, Semin, Ok, Jehyung, Yoo, Jung Il, Kim, Yong Sook, Ahn, Youngkeun, Kim, Tae-il, Ko, Heung Cho, and Lee, Jae Young
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- 2022
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24. High-Performance Implantable Bioelectrodes with Immunocompatible Topography for Modulation of Macrophage Responses
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Lee, Sanghun, Park, Junggeon, Kim, Semin, Ok, Jehyung, Yoo, Jung Il, Kim, Yong Sook, Ahn, Youngkeun, Kim, Tae-il, Ko, Heung Cho, and Lee, Jae Young
- Abstract
Implantable bioelectrodes enable precise recording or stimulation of electrical signals with living tissues in close contact. However, their performance is frequently compromised owing to inflammatory tissue reactions, which macrophages either induce or resolve by polarizing to an inflammatory (M1) or noninflammatory (M2) phenotype, respectively. Thus, we aimed to fabricate biocompatible and functional implantable conductive polymer bioelectrodes with optimal topography for the modulation of macrophage responses. To this end, we produced heparin-doped polypyrrole (PPy/Hep) electrodes of different surface roughness, with Ravalues from 5.5 to 17.6 nm, by varying the charge densities during electrochemical synthesis. In vitroculture revealed that macrophages on rough PPy/Hep electrodes preferentially polarized to noninflammatory phenotypes. In particular, PPy/Hep-900 (Ra= 14 nm) was optimal with respect to electrochemical properties and the suppression of inflammatory M1 polarization. In vivoimplantation indicated that PPy/Hep-900 significantly reduced macrophage recruitment, suppressed inflammatory polarization, and mitigated fibrotic tissue formation. In addition, the implanted PPy/Hep-900 electrodes could successfully record electrocardiographic signals for up to 10 days without substantial decreases in sensitivity, while other electrodes substantially lost their signal sensitivity during implantation. Altogether, we demonstrate that modulating the surface features of PPy/Hep can benefit the design and applications of high-performance and high-biocompatibility bioelectrodes.
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- 2022
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25. Region-based analysis of rare genomic variants in whole-genome sequencing datasets reveal two novel Alzheimer’s disease-associated genes: DTNBand DLG2
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Prokopenko, Dmitry, Lee, Sanghun, Hecker, Julian, Mullin, Kristina, Morgan, Sarah, Katsumata, Yuriko, Weiner, Michael W., Fardo, David W., Laird, Nan, Bertram, Lars, Hide, Winston, Lange, Christoph, and Tanzi, Rudolph E.
- Abstract
Alzheimer’s disease (AD) is a genetically complex disease for which nearly 40 loci have now been identified via genome-wide association studies (GWAS). We attempted to identify groups of rare variants (alternate allele frequency <0.01) associated with AD in a region-based, whole-genome sequencing (WGS) association study (rvGWAS) of two independent AD family datasets (NIMH/NIA; 2247 individuals; 605 families). Employing a sliding window approach across the genome, we identified several regions that achieved association pvalues <10−6, using the burden test or the SKAT statistic. The genomic region around the dystobrevin beta (DTNB) gene was identified with the burden and SKAT test and replicated in case/control samples from the ADSP study reaching genome-wide significance after meta-analysis (pmeta= 4.74 × 10−8). SKAT analysis also revealed region-based association around the Discs large homolog 2 (DLG2) gene and replicated in case/control samples from the ADSP study (pmeta= 1 × 10−6). In conclusion, in a region-based rvGWAS of AD we identified two novel AD genes, DLG2and DTNB, based on association with rare variants.
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- 2022
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26. Structural characteristics and thermal properties of regenerated cellulose, hemicellulose and lignin after being dissolved in ionic liquids.
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Im, Jaewan, Lee, Sanghun, Jo, Insol, Kang, Jeong Won, and Kim, Ki-Sub
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HEMICELLULOSE ,IONIC liquids ,THERMAL properties ,CELLULOSE ,LIGNINS ,INFRARED spectroscopy - Abstract
[Display omitted] This study investigated the use of ionic liquids such as 1-butyl-3-methylimidazolium chloride, 4-butyl-4-methyl morpholinium chloride, 1-butyl-1-methylpiperidinium chloride, and 1,3-dimethylimidazolium methylphosphite to dissolve cellulose, hemicellulose, and lignin biomass, as alternatives to highly toxic organic solvents. The biomass treated with the ionic liquids is characterized by scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and Fourier-transform infrared spectroscopy. The X-ray diffraction results revealed that most of the biomass treated with ionic liquids had low crystallinity after treatment with the ionic liquids. Thermogravimetric analysis confirmed that the pyrolysis temperature of the biomass treated with the ionic liquid decreased. However, it was found that the pyrolysis temperature of the biomass was increased again after the ionic liquid was washed with an antisolvent. This result was interpreted using Fourier-transform infrared spectroscopy to show that the O–H hydrogen bonding of cellulose was restored. The experimental results from this study can help provide a better understanding of the biomass regeneration mechanism of ionic liquids and increase the applicability of biomass in various fields. [ABSTRACT FROM AUTHOR]
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- 2022
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27. Deep Learning Model Comparison Study on Temperature Control in Electric Facilities
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Lee, Sanghun and Kang, Jeong Won
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Control systems have evolved along with industrial electric facility development and are very important in the manufacturing processes. This paper compared various temperature control models: proportional, integral and derivative control (PID) model, model-predictive control (MPC) model, and long short-term memory (LSTM) models. The micro temperature control lab (TClab) was using for evaluating the performance of those control models. First, temperature predictive model for model predictive control (MPC) was proposed. We compared physics-based energy balance model, first order plus dead-time (FOPDT) model and neural network-based LSTM model for the predictive model of the future temperature of TClab. The model was used to identify future temperature by using the heater’s response and current temperature. The FOPDT and LSTM models have 97–98% of accuracy as the predictive model. Second, the performance of the various control models was compared with a specific temperature profile. The conventional PID control has 1.988 °C/sec errors between the target temperature and the actual temperature in the designated temperature profile. The average error value of the model is lower (1.766 °C/sec errors) due to the predictive model and optimization. The accuracy of MPC is 12.4% higher than that of the PID model. Neural network based deep learning control model is clearly more accurate the PID model. When LSTM model was trained with optimal parameters, The average error between the target temperature and the actual temperature of LSTM model is 1.752 °C/sec. This is 13.5% higher accuracy than that of the conventional PID model. Our experiment results well explained the difference of various temperature control models and they showed that the LSTM model can greatly improve the accuracy with optimized parameters and showed the possibility for the next intelligent control system with massive amounts of data accumulated.
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- 2022
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28. Objective quantification of the impact of blepharoplasty on the superior visual field
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Kim, Hyodong, Lee, Sanghun, Son, Daegu, and Yeo, Hyeonjung
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- 2022
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29. Integrated genetic and epigenetic analyses uncover MSI2 association with allergic inflammation.
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Kim, Kyung Won, Park, Sang-Cheol, Cho, Hyung-Ju, Jang, Haerin, Park, Jaehyun, Shim, Hyo Sup, Kim, Eun Gyul, Kim, Mi Na, Hong, Jung Yeon, Kim, Yoon Hee, Lee, Sanghun, Weiss, Scott T., Kim, Chang-Hoon, Won, Sungho, and Sohn, Myung Hyun
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The relationship between allergic and eosinophilic inflammation, either systemic or local, in allergic diseases remains unclear. We performed combined genome-wide association study (GWAS) and epigenome-wide (EWAS) for atopy and tissue eosinophilia to identify both genetic and epigenetic signatures between systemic and local allergic inflammation, and to capture global patterns of gene regulation. We included 126 subjects for atopy analysis and 147 for tissue eosinophilia analysis, as well as 18 normal nasal tissue samples. We identified differentially methylated positions (DMPs) and genes associated with atopy and tissue eosinophilia. Furthermore, we performed mendelian randomization analysis and penalized regression along with replication in an independent cohort. EWAS identified genes, including Musashi RNA binding protein 2 (MSI2) , associated with atopy, which contained enriched DMPs that genetically affect atopy. A direct association was observed between MSI2 single-nucleotide polymorphisms and atopy, as was a causal effect of changes in MSI2 expression and methylation on atopy, which was replicated in a Costa Rican population. Regarding tissue eosinophilia, EWAS identified genes with enriched DMPs directly contributing to tissue eosinophilia at the gene level, including CAMK1D. The gene ontology terms of the identified genes for both phenotypes encompassed immune-related terms. EWAS combined with GWAS identified novel candidate genes, especially the methylation of MSI2 , contributing to systemic allergic inflammation. Certain genes displayed a greater association with either systemic or local allergic inflammation; however, it is expected that a harmonized effect of these genes influences immune responses. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2021
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30. Dynamics and Entropy of Cyclohexane Rings Control pH-Responsive Reactivity
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Kang, Sunyoung, Noh, Chanwoo, Kang, Hyosik, Shin, Ji-Yeon, Kim, So-Young, Kim, Seulah, Son, Moon-Gi, Park, Eunseok, Song, Hyun Kyu, Shin, Seokmin, Lee, Sanghun, Kim, Nak-Kyoon, Jung, YounJoon, and Lee, Yan
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Activation entropy (ΔS‡) is not normally considered the main factor in determining the reactivity of unimolecular reactions. Here, we report that the intramolecular degradation of six-membered ring compounds is mainly determined by the ΔS‡, which is strongly influenced by the ring-flipping motion and substituent geometry. Starting from the unique difference between the pH-dependent degradation kinetics of geometric isomers of 1,2-cyclohexanecarboxylic acid amide (1,2-CHCAA), where only the cisisomer can readily degrade under weakly acidic conditions (pH < 5.5), we found that the difference originated from the large difference in ΔS‡of 16.02 cal·mol–1·K–1. While cis-1,2-CHCAA maintains a preference for the classical chair cyclohexane conformation, trans-1,2-CHCAA shows dynamic interconversion between the chair and twisted boat conformations, which was supported by both MD simulations and VT-NMR analysis. Steric repulsion between the bulky 1,2-substituents of the transisomer is one of the main reasons for the reduced energy barrier between ring conformations that facilitates dynamic ring inversion motions. Consequently, the more dynamic transisomer exhibits much a larger loss in entropy during the activation process due to the prepositioning of the reactant than the cisisomer, and the pH-dependent degradation of the transisomer is effectively suppressed. When the ring inversion motion is inhibited by an additional methyl substituent on the cyclohexane ring, the pH degradability can be dramatically enhanced for even the transisomer. This study shows a unique example in which spatial arrangement and dynamic properties can strongly influence molecular reactivity in unimolecular reactions, and it will be helpful for the future design of a reactive structure depending on dynamic conformational changes.
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- 2021
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31. Effects of drought stress on root morphology and spatial distribution of soybean and adzuki bean
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CHUN, Hyen Chung, LEE, Sanghun, CHOI, Young Dae, GONG, Dong Hyeok, and JUNG, Ki Youl
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Due to global climate change, Korea is facing severe droughts that affect the planting and early vegetative periods of upland crops. Soybean and adzuki bean are important legume crops in Korea, so it is critical to understand their adaptations to water stress. This study investigated the changes in root morphological properties in soybean and adzuki bean and quantified the findings using fractal analysis. The experiment was performed at the National Institute of Crop Science in Miryang, Korea. Soybeans and adzuki beans were planted in test boxes and grown for 30 days. The boxes were filled with bed soil with various soil moisture treatments. Root images were obtained and scanned every two days, and the root properties were characterized by root length, depth and surface area, number of roots, and fractal parameters (fractal dimension and lacunarity). Root depth, length and surface area and the number of roots increased in both crops as the soil moisture content increased. The fractal dimension and lacunarity values increased as the soil moisture content increased. These results indicated that the greater the soil moisture, the more heterogeneous the root structure. Correlation analysis of the morphological properties and fractal parameters indicated that soybean and adzuki bean had different root structure developments. Both soybean and adzuki bean were sensitive to the amount of soil moisture in the early vegetative stage. Soybean required a soil moisture content greater than 70% of the field capacity to develop a full root structure, while adzuki bean required 100% of the field capacity. These results would be useful in understanding the responses of soybean and adzuki bean to water stress and managing irrigation during cultivation.
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- 2021
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32. Resting energy expenditure differs among individuals with different levels of perceived thermal sensitivity: A cross-sectional study
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Mun, Sujeong, Yoo, Junghun, Lee, Sanghun, Yim, Mi Hong, Kim, Soyoung, Kim, Daehyeok, Kim, Min-Ji, Lee, Youngseop, and Park, Jeong Hwan
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Metabolic rate has been used in thermophysiological models for predicting the thermal response of humans. However, only a few studies have investigated the association between an individual’s trait-like thermal sensitivity and resting energy expenditure (REE), which resulted in inconsistent results. This study aimed to explore the association between REE and perceived thermal sensitivity. The REE of healthy adults was measured using an indirect calorimeter, and perceived thermal intolerance and sensation in the body were evaluated using a self-administered questionnaire. In total, 1567 individuals were included in the analysis (women = 68.9%, age = 41.1 ± 13.2 years, body mass index = 23.3 ± 3.3 kg/m2, REE = 1532.1 ± 362.4 kcal/d). More women had high cold intolerance (31.8%) than men (12.7%), and more men had high heat intolerance (23.6%) than women (16.1%). In contrast, more women experienced both cold (53.8%) and heat (40.6%) sensations in the body than men (cold, 29.1%; heat, 27.9%). After adjusting for age, fat-free mass, and fat mass, lower cold intolerance, higher heat intolerance, and heat sensation were associated with increased REE only in men (cold intolerance, Pfor trend = .001; heat intolerance, Pfor trend = .037; heat sensation, P = .046), whereas cold sensation was associated with decreased REE only in women (P = .023). These findings suggest a link between the perceived thermal sensitivity and REE levels in healthy individuals.
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- 2024
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33. Novel recessive locus for body mass index in childhood asthma
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Lee, Sanghun, Lasky-Su, Jessica, Won, Sungho, Laurie, Cecelia, Celedón, Juan Carlos, Lange, Christoph, Weiss, Scott, and Hecker, Julian
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Most genome-wide association studies of obesity and body mass index (BMI) have so far assumed an additive mode of inheritance in their analysis, although association testing supports a recessive effect for some of the established loci, for example, rs1421085 in FTO. In two whole-genome sequencing (WGS) studies of children with asthma and their parents (892 Costa Rican trios and 286 North American trios), we discovered an association between a locus (rs9292139) in LOC102724122and BMI that reaches genome-wide significance under a recessive model in the combined analysis. As the association does not achieve significance under an additive model, our finding illustrates the benefits of the recessive model in WGS analyses.
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- 2021
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34. Adverse events related to electroacupuncture: a systematic review of single case studies and case series
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Park, Jeong Hwan, Lee, Jun-Hwan, Lee, Sanghun, Shin, Jae-Young, and Kim, Tae-Hun
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Objective Electroacupuncture (EA) is used in the treatment of various diseases through the use of electrical stimulation. Reports of adverse events (AEs) associated with acupuncture are relatively consistent, but the safety of EA has been less well reported. In this systematic review, we provide a summary of the types of AEs related to EA in clinical practice.Methods Twelve electronic databases, including those in English (PubMed, Ovid-EMBASE, CENTRAL), Korean (KMbase, KISS, NDSL, KISTI, OASIS), Chinese (CNKI, Wanfang, Weipu) and Japanese (J-STAGE), were systematically searched for single case studies and case series through April 2018. There were no language restrictions. We included clinical studies in which EA was used as a key intervention and in which AEs that may have been causally related to EA were reported.Results Thirty-seven studies, including 27 single case studies and 10 case series, were evaluated. The most frequently reported AEs were pallor (eight cases), skin pigmentation (eight cases), vertigo (seven cases), chest tightness (six cases), vomiting (six cases) and unconsciousness (five cases). Thirty-one cases (62%) achieved full recovery and three cases (6%) achieved partial recovery. There were also three cases of death (6%).Conclusion AEs related to EA included acupuncture-related AEs and serious AEs induced by electrical stimulation. Currently, specific stimulation conditions associated with EA-specific AEs are not identifiable due to inappropriate reporting. However, skin pigmentation, syncope or spasm, implantable cardioverter-defibrillator shock, cardiac emergencies, electrical burns, and potential internal organ injury are potential EA-specific AEs regarding which physicians should be cautious in clinical practice.
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- 2020
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35. Parental involvement in the manual reduction of pulled elbow in children
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Cho, Wonjin, Lee, Seung Chul, Lee, Jeong Hun, Seo, Jun Seok, Do, Han Ho, Kim, Yong Won, and Lee, Sanghun
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- 2020
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36. Design of 20 Nm3/h Class Liquid Organic Hydrogen Carrier System Integrated with Electrolyzer and Fuel Cell
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Lee, Sanghun, Kim, Taehong, Han, Gwangwoo, and Bae, Joongmyeon
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As renewable energy sources account for a larger portion of power generation, a hydrogen energy storage system (HESS) attracts attention for large capacity energy storage. At HESS, surplus electricity is used to produce hydrogen, and it is stored in compressed hydrogen tanks, and the hydrogen is utilized to generate electricity when electricity demand is high. Recently, liquid organic hydrogen carrier (LOHC) is proposed for hydrogen storage. LOHC is one of the hydrogen storage methods in which hydrogen is stored by the reaction with aromatic compounds. By using LOHC systems, high hydrogen storage density, and good safety are achievable. In this study, 20 Nm3/h class LOHC system with dibenzyltoluene (DBT) is designed. For the system design, catalytic performance, NMR analysis, and vapor pressure of DBT are evaluated, and a LOHC system composed of hydrogenation, dehydrogenation reactors, condenser, and adsorbent is designed for future demonstration.
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- 2020
37. In Situ Observation of the Effect of Accelerating Voltage on Electron Beam Damage of Layered Cathode Materials for Lithium-Ion Batteries.
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Shim, Jae-Hyun, Kang, Hyosik, Kim, Young-Min, and Lee, Sanghun
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- 2019
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38. Electrical Conductivity of Delithiated Lithium Cobalt Oxides: Conductive Atomic Force Microscopy and Density Functional Theory Study.
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Kang, Hyosik, Lee, Jaehan, Rodgers, Thomas, Shim, Jae-Hyun, and Lee, Sanghun
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- 2019
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39. Hierarchically Structured Core–Shell Design of a Lithium Transition-Metal Oxide Cathode Material for Excellent Electrochemical Performance.
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Shim, Jae-Hyun, Kim, Young-Hoon, Yoon, Han-Sol, Kim, Han-A, Kim, Ji-Soo, Kim, Jongsik, Cho, Nam-Hee, Kim, Young-Min, and Lee, Sanghun
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- 2019
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40. Feasibility study of structured diagnosis methods for functional dyspepsia in Korean medicine clinics
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Park, Jeong Hwan, Kim, Soyoung, Park, Jae-Woo, Ko, Seok-Jae, and Lee, Sanghun
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Functional dyspepsia (FD) is the seventh most common disease encountered in Korean medicine (KM) clinics. Despite the large number of FD patients visiting KM clinics, the accumulated medical records have no utility in evidence development, due to being unstructured. This study aimed to construct a standard operating procedure (SOP) with appropriate structured diagnostic methods for FD, and assess the feasibility for use in KM clinics.
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- 2024
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41. Development of an ultrasound-imaging procedure and acquisition of ultrasound images of acupuncture points for safety and accuracy of needle insertion
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Kim, Sungha, Lee, Sanghun, Ha, Won-Bae, Lee, Jung-Han, Jung, Hyun-Jong, Chu, Hong-Min, Yang, Seung-Bum, Choi, Sunmi, Son, Mi Ju, Kim, Jae Hyo, and Jeon, Youngju
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Acupuncture is a relatively safe, commonly used “alternative” medical treatment for various symptoms. However, adverse effects can occur, including trauma, pneumothorax, and central-nervous-system injury. Our objective was to develop a reliable and practical procedure for ultrasound imaging of acupuncture points to improve safety during needling, and to acquire ultrasound images of several (44) acupuncture points, especially those in high-risk areas, according to an in-house standard operating procedure.
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- 2024
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42. Pinuseldarone, a Clerodane-Type Diterpene from Pinus eldaricaNeedles and Phytochemicals as Novel Agents for Regulating Brown Adipogenesis and Thermogenesis
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Cho, Yeo Rang, Lee, Sanghun, Kim, Hyoju, Park, Eon Chung, Jeong, Se Yun, Hamishehkar, Hamed, Jung, Su Myung, and Kim, Ki Hyun
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Phytochemical investigation of the MeOH extract of Pinus eldaricaneedles led to the isolation and identification of a new clerodane-type diterpene, pinuseldarone (1), along with a known flavonoid, 5,4′-dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2), through HPLC purification. The structure of the new compound 1was elucidated using spectroscopic methods, including 1D and 2D NMR, as well as HRESIMS. Its absolute configuration was established through NOESY analysis and computational methods, including electronic circular dichroism (ECD) calculations and gauge-including atomic orbital NMR chemical shift calculations, followed by DP4+ probability analysis. The metabolic implications of the isolated compounds were assessed using a cultured brown adipocyte model derived from murine brown adipose tissue. It was observed that treatment with dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2) downregulates the adipogenic marker C/EBPδ and fatty acid transporter CD36, resulting in a significant reduction in lipid accumulation during brown adipocyte differentiation. However, pinuseldarone (1) treatment did not affect brown adipocyte differentiation. Interestingly, pretreatment with pinuseldarone (1) potentiated the pharmacological stimulation of brown adipocytes, seemingly achieved by sensitizing their response to β3-adrenoreceptor signaling. Therefore, our findings indicate that phytochemicals derived from P. eldaricaneedles could potentially serve as valuable compounds for adjusting the metabolic activity of brown adipose tissue, a vital component in maintaining whole-body metabolic homeostasis.
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- 2024
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43. Association of low urine pH as a metabolic feature with abdominal obesity
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Lee, Juyoung, Chang, Hee Kyung, and Lee, Sanghun
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Objective Low urine pH (LUP) is not only affected by environmental factors, but is also a feature of metabolic syndrome (MS), which is characterized by insulin resistance, abdominal obesity, dyslipidaemia and hypertension. However, it is unclear which factors contribute most to urine acidity. This study investigated factors influencing LUP and the link between LUP and metabolic traits in South Korea.Methods Participants were middle-aged subjects (age, 52.2 ± 8.9 years; average body mass index, 24.6 ± 3.2 kg/m2), of whom 4,626 had urine pH of 5.0 and were assigned to the LUP group and 4,185 had urine pH > 5.0 and were assigned to the control group. The association between LUP and various phenotypes, including environmental and metabolic traits, was analysed.Results LUP was significantly associated with MS diagnostic components and with environmental exposures such as smoking, alcohol intake and low-fibre diet. Multivariate analysis showed that the waist-to-hip ratio was the best predictor for LUP compared with other MS components (OR: 2.439).Conclusions LUP is an indicator of MS and is mainly related to the MS diagnostic criterion of abdominal obesity, even after adjusting for environmental influences on urine acidity.
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- 2024
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44. A consistent pattern of slide effects in Illumina DNA methylation BeadChip array data
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Hecker, Julian, Lee, Sanghun, Kachroo, Priyadarshini, Prokopenko, Dmitry, Maaser-Hecker, Anna, Lutz, Sharon M., Hahn, Georg, Irizarry, Rafael, Weiss, Scott T., DeMeo, Dawn L., and Lange, Christoph
- Abstract
ABSTRACTBackground:Recent studies have identified thousands of associations between DNA methylation CpGs and complex diseases/traits, emphasizing the critical role of epigenetics in understanding disease aetiology and identifying biomarkers. However, association analyses based on methylation array data are susceptible to batch/slide effects, which can lead to inflated false positive rates or reduced statistical powerResults:We use multiple DNA methylation datasets based on the popular Illumina Infinium MethylationEPIC BeadChip array to describe consistent patterns and the joint distribution of slide effects across CpGs, confirming and extending previous results. The susceptible CpGs overlap with the Illumina Infinium HumanMethylation450 BeadChip array content.Conclusions:Our findings reveal systematic patterns in slide effects. The observations provide further insights into the characteristics of these effects and can improve existing adjustment approaches.
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- 2023
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45. Determining maximal safe needling depth based on anthropometric measurements: Focusing on acupoint GB21.
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Chu, Hongmin, Kang, Geon, Park, Seongjun, Kim, Jaehyun, Jang, Jongwon, Park, Kyungtae, Ha, Wonbae, Kim, Jae-Hyo, and Lee, Sanghun
- Abstract
Abstract Introduction BMI and body weight have been regarded as factors that determine an individual’s needling depth. But in previous research on GB21 (jianjing), we observed various cases in which subjects with the same BMI had a different safe needling depth. GB21 is high risk acupoint that can occur pneumothorax, So precise and safe treatment is required. The aim of this study was to investigate the correlation between needling depth and various anthropometric parameters, focusing on acupoint GB21. Methods Ultrasonographic images GB21 from 52 (24 male and 28 female) healthy volunteers were recorded during normal respiration. Subject‘s weight, height, neck circumference, shoulder width, chest circumference, and abdominal circumference were also measured. Results BMI was positively associated with maximal safe needling depth (r = 0.48, p < 0.001); however, NC, SW, and height showed highly significant correlations with maximal safe needling depth (NC, r = 0.75, p < 0.001; SW, r = 0.57, p < 0.001; height, r = 0.52, p < 0.001). CC and AC had lower correlations than BMI (CC, r = 0.41, p < 0.01; AC, r = 0.32, p < 0.05). Conclusion Although BMI has been traditionally used as an important index in determining needling depths, our study showed that anthropometric parameters have a higher correlation with maximal safe needling depth on a high-risk acupoint associated with organ damage. Thus, anthropometric parameters may be potentially useful as an initial screening tool to avoid adverse effects of Acupoint GB21. [ABSTRACT FROM AUTHOR]
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- 2018
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46. Potential Efficacy of Allergen Removed Rhus Verniciflua Stokes Extract to Maintain Progression-Free Survival of Patients With Advanced Hepatobiliary Cancer.
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Chae, Jean, Lee, Sanghun, and Lee, Sookyung
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Hepatobiliary cancers are among the leading causes of cancer-related deaths worldwide. Most of the early-stage, surgically resectable cases show recurrence, and when they do, the prognosis is dismal with limited available treatment options. Here, we report three patients with relapsed hepatobiliary cancers who presented relatively long progression-free survival with the administration of a natural product, allergen removed Rhus verniciflua Stokes (RVS) extract. After commencement of RVS extract, they were progression-free for over 56 months in one case of recurred cholangiocarcinoma, and for over 16 and 114 months respectively, in two cases of advanced hepatocellular carcinoma. These cases suggest that the RVS extract could be a potential alternative for advanced hepatobiliary cancer that has no other available treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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47. Integrative treatment package for degenerative disc disease in the lumbar spine: A retrospective case series.
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Park, Yeoncheol, Goo, Bonhyuk, Lee, Sanghun, Baek, Yonghyeon, Nam, Sangsoo, Kim, Donghwan, Jo, Daejean, Kim, Kitack, Kim, Sungmin, and Seo, Byungkwan
- Abstract
Introduction This is a retrospective case series exploring the therapeutic benefits of acupuncture-related modalities in combination with standard care (integrative treatment) for people with degenerative disc disease (DDD) with axial low back pain. Methods The medical records of 24 patients with DDD were retrospectively reviewed and their demographic and clinical characteristics recorded. They were grouped into two according to the therapeutic intervention. The disability and pain intensity of the low back were measured using Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS). The rate of improvement was studied retrospectively to evaluate the feasibility of acupuncture-related modalities as part of combination therapy. Result Of the 24 patients who met the eligibility criteria, 11 (45.8%) received integrative treatment. There were significant reductions in the disability and pain intensity in 11 patients who received an integrative package care (P < 0.05). Additionally, clinically relevant changes in the mean differences and improvement rates of ODI and NRS were observed in both groups; however, the differences in ODI and NRS (11.09 and 2.18, respectively) and improvement rates (33.82% and 39.09%, respectively) were greater in integrative treated patients than in conventionally treated ones. Conclusions This study describes the use of acupuncture-related modalities and raises the possibilities of their use in combination therapy for the improvement of function and pain management in patients with DDD. In light of these promising results, future clinical trials with attention to appropriate patient selection, guidelines for integrative treatment, and optimal standards for outcome measurement are necessary to evaluate the effectiveness of integrative treatment. [ABSTRACT FROM AUTHOR]
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- 2018
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48. In Situ Observation of the Effect of Accelerating Voltage on Electron Beam Damage of Layered Cathode Materials for Lithium-Ion Batteries
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Shim, Jae-Hyun, Kang, Hyosik, Kim, Young-Min, and Lee, Sanghun
- Abstract
Electron beam damage from transmission electron microscopy of layered lithium transition-metal oxides is a threshold phenomenon that depends on the electron beam energy, which we demonstrate in this study by varying the accelerating voltage of a scanning transmission electron microscope. The electron beam irradiation experiment shows that Ni in LiNiO2has much lower threshold energy for displacement than Co in LiCoO2, which is supported by DFT calculations predicting that Ni has lower migration energy. The transition-metal ions are reduced from the oxidation state of +3 to +2 during migration from their original positions to the lithium sites, and Ni is more easily reduced than Co because of its electronic configuration. In addition, the high-energy electron beam induces oxygen release, which is another symptom of degradation of materials that occurs more strongly in Ni-containing materials with ion displacement.
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- 2019
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49. Electrical Conductivity of Delithiated Lithium Cobalt Oxides: Conductive Atomic Force Microscopy and Density Functional Theory Study
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Kang, Hyosik, Lee, Jaehan, Rodgers, Thomas, Shim, Jae-Hyun, and Lee, Sanghun
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LiCoO2, one of the most popular cathode materials for lithium-ion batteries, is well known for undergoing insulator–metal transitions depending on the amount of lithium ions. In this study, we successfully visualize the change in the electrical conductivity of LiCoO2without synthesizing large single crystals using conductive atomic force microscopy and high-resolution scanning electron microscopy. As expected, the anisotropic conductivity is observed only in the (003) plane. The electronic structures of LiCoO2, CoO2, and Li0.5CoO2are studied from density functional theory calculation. This systematic calculation is in good agreement with the previously reported experimental finding that electron holes of hybrid orbitals of Co4+(a1g) and oxygen (2p), which are produced by the lithium vacancy, contribute to the electrical conductivity of delithiated lithium cobalt oxides.
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- 2019
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50. Hierarchically Structured Core–Shell Design of a Lithium Transition-Metal Oxide Cathode Material for Excellent Electrochemical Performance
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Shim, Jae-Hyun, Kim, Young-Hoon, Yoon, Han-Sol, Kim, Han-A, Kim, Ji-Soo, Kim, Jongsik, Cho, Nam-Hee, Kim, Young-Min, and Lee, Sanghun
- Abstract
Tuning geometrical parameters of lithium-mixed transition-metal oxide (LiTM) cathode materials is a promising strategy for resource-efficient design of high-performance Li-ion batteries. In this paper, we demonstrate that simple and facile geometrical tailoring of the secondary microstructure of LiTM cathode materials without complex chemical modification or heterostructure engineering can significantly improve overall electrochemical performance of the active cathode materials. An optimized LiTM with a bimodal size distribution of primary particles inside the secondary particles exhibits a 53.8% increase in capacity at a high discharge rate (10 C) compared to a commercially available reference and comparable rate capability after 100 charge/discharge cycles. The key concept of this approach is to maximize the beneficial effects arising from the controlled sizes of primary particles. Multimodal/multiscale microscopic characterizations based on electron tomography and scanning transmission electron microscopy, combined with electron energy-loss spectroscopy and energy-dispersive X-ray spectroscopy from the atomic level to the microscale level, were employed to elucidate structural origins of enhanced battery performance. This study paves the way for the resource-efficient microstructure design of LiTM cathode materials to maximize capacity and stability via simple adjustment of processing conditions, which is advantageous for mass-production applications.
- Published
- 2019
- Full Text
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