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Kim SA, Chung YS, Lee BJ. Recurrence patterns of sinonasal cancers after a 5-year disease-free period. Laryngoscope 2019; 129:2451-2457. [PMID: 30794325 DOI: 10.1002/lary.27866] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/22/2019] [Indexed: 12/30/2022]
Abstract
OBJECTIVES/HYPOTHESIS Sinonasal cancers are rare but have a poor prognosis. Most previous studies of these cancers have focused on 5-year disease-free survival, but recurrences are also known to occur after this period. We examined the post-5-year recurrence patterns in sinonasal cancer patients by histologic type to determine the indicators for extended and close follow-up requirements. STUDY DESIGN Retrospective chart review. METHODS A cohort of 241 sinonasal cancer patients was included. Demographic data, cancer site and stage, pathology and treatment results, and follow-up and survival data were collected. RESULTS Of the 241 patients, a complete remission occurred in 163 (72.4%) patients, but 83 (50.9%) of these cases developed recurrence, which occurred beyond the 5-year follow-up period in 19 cases (11.7%). The most common post-5-year recurrences were adenoid cystic carcinoma (six patients, 33.3%), followed by melanoma (three patients, 21.4%), poorly differentiated carcinoma (two patients, 18.2%), squamous cell carcinoma (six patients, 6.7%), and olfactory neuroblastoma (no patients, 0%). Post-5-year local recurrence was highest in adenoid cystic carcinoma (six patients, 33.3%), followed by melanoma (three patients, 21.4%), poorly differentiated carcinoma (two patients, 18.2%), and squamous cell carcinoma (five patients, 5.5%). Post-5-year regional recurrence occurred in one squamous carcinoma patient (1.1%), and distant metastasis was seen in one adenoid cystic carcinoma patient (5.5%). CONCLUSIONS Sinonasal cancer shows an 11.7% recurrence rate after a 5-year disease-free period. As this recurrence pattern varies by tumor pathology, a specific follow-up plan is needed for each cancer type. LEVEL OF EVIDENCE 3 Laryngoscope, 129:2451-2457, 2019.
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Lattery DM, Kim M, Choi J, Lee BJ, Wang X. Effective Radiative Properties of Tilted Metallic Nanorod Arrays Considering Polarization Coupling. Sci Rep 2018; 8:13896. [PMID: 30224764 PMCID: PMC6141545 DOI: 10.1038/s41598-018-32265-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/05/2018] [Indexed: 11/29/2022] Open
Abstract
With the advent of new nanomanufacturing techniques has come the rise of the field of nanophotonics and an increased need to determine optical properties of novel structures. Commercial software packages are able to estimate the behavior, but require large resources and heavy computational time. By combining coordinate transforms and Effective Medium Theory (EMT), an effective relative permittivity tensor is defined and further exploited to calculate the polarization-coupled Fresnel coefficients through Maxwell’s equations. A uniaxial simplification is made to show the case of tilted nanorod arrays. To demonstrate the flexibility of this system, the interfacial reflectance has been calculated for both s- and p-polarizations as well as the coupled case with the volume filling fractions of f = 0.10 and 0.30 for silver (Ag) and titanium (Ti) nanorods, and a scenario of a Ag nanorod array with polymethyl methacrylate (PMMA) as the surrounding medium. The exact results computed by the finite-difference time-domain method justify the validity of EMT with polarization coupling taken into account. The effects of incidence angle and azimuthal angle on reflectance are also discussed. The relatively simple nature of this approach allows for fast estimations of the optical properties of various nanostructures.
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Rho J, Lim M, Lee SS, Lee BJ. AFM-thermoreflectance for simultaneous measurements of the topography and temperature. RSC Adv 2018; 8:27616-27622. [PMID: 35542752 PMCID: PMC9083913 DOI: 10.1039/c8ra05937c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 07/27/2018] [Indexed: 11/21/2022] Open
Abstract
To understand the thermal failure mechanisms of electronic devices, it is essential to measure the temperature and characterize the thermal properties of individual nanometer-scale transistors in electronic devices. Previously, scanning thermal microscopy (SThM) has been used to measure the local temperature with nanometer-scale spatial resolutions using a probe with a built-in temperature sensor. However, this type of temperature measurement requires additional equipment to process the temperature-sensing signals and expensive temperature-sensor-integrated probes fabricated by complicated MEMS processes. Here, we present a novel technique which enables the simultaneous measurement of the temperature and topography of nanostructures only with a conventional atomic force microscope (AFM) of the type commonly used for topography measurements and without any modifications of the probe and extra accessories for data acquisition. The underlying principle of the proposed technique is that the local temperature of a specimen is estimated quantitatively from the thermoreflectance of a bare silicon AFM probe that is in contact with a specimen. The temperature obtained by our technique is found to be consistent with a result obtained by SThM measurements. We propose a novel form of AFM-based thermometry capable of sub-100 nm spatial resolution only with a conventional AFM setup by exploiting the thermoreflectance characteristic of the AFM Si probe.![]()
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Jin H, Kim MG, Ko SB, Kim DH, Lee BJ, Macgregor RB, Shim G, Oh YK. Stemmed DNA nanostructure for the selective delivery of therapeutics. NANOSCALE 2018; 10:7511-7518. [PMID: 29637946 DOI: 10.1039/c7nr08558c] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
DNA has emerged as a biocompatible biomaterial that may be considered for various applications. Here, we report tumor cell-specific aptamer-modified DNA nanostructures for the specific recognition and delivery of therapeutic chemicals to cancer cells. Protein tyrosine kinase (PTK)7-specific DNA aptamer sequences were linked to 15 consecutive guanines. The resulting aptamer-modified product, AptG15, self-assembled into a Y-shaped structure. The presence of a G-quadruplex at AptG15 was confirmed by circular dichroism and Raman spectroscopy. The utility of AptG15 as a nanocarrier of therapeutics was tested by loading the photosensitizer, methylene blue (MB), to the G-quadruplex as a model drug. The generated MB-loaded AptG15 (MB/AptG15) showed specific and enhanced uptake to CCRF-CEM cells, which overexpress PTK7, compared with Ramos cells, which lack PTK7, or CCRF-CEM cells treated with a PTK7-specific siRNA. The therapeutic activity of MB/AptG15 was tested by triggering its photodynamic effects. Upon 660 nm light irradiation, MB/AptG15 showed greater reactive oxygen species generation and anticancer activity in PTK7-overexpressing cells compared to cells treated with MB alone, those treated with AptG15, and other comparison groups. AptG15 stemmed DNA nanostructures have significant potential for the cell-type-specific delivery of therapeutics, and possibly for the molecular imaging of target cells.
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Nucifora LG, Tanaka T, Hayes LN, Kim M, Lee BJ, Matsuda T, Nucifora Jr FC, Sedlak T, Mojtabai R, Eaton W, Sawa A. Reduction of plasma glutathione in psychosis associated with schizophrenia and bipolar disorder in translational psychiatry. Transl Psychiatry 2017; 7:e1215. [PMID: 28892069 PMCID: PMC5611744 DOI: 10.1038/tp.2017.178] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 06/02/2017] [Accepted: 06/07/2017] [Indexed: 01/13/2023] Open
Abstract
The establishment of mechanism-driven peripheral markers is important for translational psychiatry. Many groups, including ours, have addressed molecular alterations in peripheral tissues in association with symptomatic changes in major illnesses. Oxidative stress is implicated in the pathophysiology of schizophrenia (SZ) and bipolar disorder (BP) through studies of patient peripheral tissues and animal models. Although the relationship between peripheral changes and brain pathology remain elusive, oxidative stress may bridge such translational efforts. Nonetheless, the molecular substrates of oxidative stress are not well defined in mental conditions. Glutathione (GSH) is a non-enzymatic antioxidant that eliminates free radicals, and has been suggested to have a role in SZ. We performed a cross-sectional study of 48 healthy controls (CON), 52 SZ patients and 62 BP patients to compare the levels of peripheral GSH by a biochemical enzyme assay. We show a significant reduction of plasma GSH in both SZ and BP patients compared with CON. We evaluated possible influences of clinical characteristics on the level of GSH in SZ and BP. A decrease in GSH level correlated with Positive and Negative Syndrome Scale (PANSS) total and positive scores for SZ and correlated with the PANSS general for BP. Taken together, we provide evidence that SZ and BP display a common molecular signature in the reduction of peripheral GSH in the psychosis dimension.
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Yun J, Ahn JH, Lee BJ, Moon DI, Choi YK, Park I. Temperature measurement of Joule heated silicon micro/nanowires using selectively decorated quantum dots. NANOTECHNOLOGY 2016; 27:505705. [PMID: 27869647 DOI: 10.1088/0957-4484/27/50/505705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We developed a novel method to measure local temperature at micro/nano-scale regions using selective deposition of quantum dots (QDs) as a sensitive temperature probe and measured the temperature of Joule heated silicon microwires (SiMWs) and silicon nanowires (SiNWs) by this method. The QDs are selectively coated only on the surface of the SiMWs and SiNWs by a sequential process composed of selective opening of a polymethyl methacrylate layer via Joule heating, covalent bonding of QDs, and lift-off process. The temperatures of the Joule-heated SiMWs and SiNWs can be measured by characterizing the temperature-dependent shift of photoluminescence peak of the selectively deposited QDs even with far-field optics. The validity of the extracted temperature has been also confirmed by comparing with numerical simulation results. The proposed method can potentially provide micro/nanoscale measurement of localized temperatures for a wide range of electrical and optical devices.
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Dulhani J, Lee BJ. Effect of Constriction on Phonon Transport in Silicon Thin Films and Nanowires. SMART SCIENCE 2016. [DOI: 10.1080/23080477.2016.1229101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ben SB, Peng B, Wang GC, Li C, Gu HF, Jiang H, Meng XL, Lee BJ, Chen CL. Overexpression of Selenoprotein SelK in BGC-823 Cells Inhibits Cell Adhesion and Migration. BIOCHEMISTRY (MOSCOW) 2016; 80:1344-53. [PMID: 26567579 DOI: 10.1134/s0006297915100168] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Effects of human selenoprotein SelK on the adhesion and migration ability of human gastric cancer BGC-823 cells using Matrigel adhesion and transwell migration assays, respectively, were investigated in this study. The Matrigel adhesion ability of BGC-823 cells that overexpressed SelK declined extremely significantly (p < 0.01) compared with that of the cells not expressing the protein. The migration ability of BGC-823 cells that overexpressed SelK also declined extremely significantly (p < 0.01). On the other hand, the Matrigel adhesion ability and migration ability of the cells that overexpressed C-terminally truncated SelK did not decline significantly. The Matrigel adhesion ability and migration ability of human embryonic kidney HEK-293 cells that overexpressed SelK did not show significant change (p > 0.05) with the cells that overexpressed the C-terminally truncated protein. In addition to the effect on Matrigel adhesion and migration, the overexpression of SelK also caused a loss in cell viability (as measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) colorimetric assay) and induced apoptosis as shown by confocal microscopy and flow cytometry. The cytosolic free Ca2+ level of these cells was significantly increased as detected by flow cytometry. But the overexpression of SelK in HEK-293 cells caused neither significant loss in cell viability nor apoptosis induction. Only the elevation of cytosolic free Ca2+ level in these cells was significant. Taken together, the results suggest that the overexpression of SelK can inhibit human cancer cell Matrigel adhesion and migration and cause both the loss in cell viability and induction of apoptosis. The release of intracellular Ca2+ from the endoplasmic reticulum might be a mechanism whereby the protein exerted its impact. Furthermore, only the full-length protein, but not C-terminally truncated form, was capable of producing such impact. The embryonic cells were not influenced by the elevation of free Ca2+ level in cytosol, probably due to their much greater tolerance to the variation.
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Jin S, Lim M, Lee SS, Lee BJ. Hyperbolic metamaterial-based near-field thermophotovoltaic system for hundreds of nanometer vacuum gap. OPTICS EXPRESS 2016; 24:A635-A649. [PMID: 27136882 DOI: 10.1364/oe.24.00a635] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Artificially designed hyperbolic metamaterial (HMM) possesses extraordinary electromagnetic features different from those of naturally existing materials. In particular, the dispersion relation of waves existing inside the HMM is hyperbolic rather than elliptical; thus, waves that are evanescent in isotropic media become propagating in the HMM. This characteristic of HMMs opens a novel way to spectrally control the near-field thermal radiation in which evanescent waves in the vacuum gap play a critical role. In this paper, we theoretically investigate the performance of a near-field thermophotovoltaic (TPV) energy conversion system in which a W/SiO2-multilayer-based HMM serves as the emitter at 1000 K and InAs works as the TPV cell at 300 K. By carefully designing the thickness of constituent materials of the HMM emitter, the electric power of the near-field TPV devices can be increased by about 6 times at 100-nm vacuum gap as compared to the case of the plain W emitter. Alternatively, in regards to the electric power generation, HMM emitter at experimentally achievable 100-nm vacuum gap performs equivalently to the plain W emitter at 18-nm vacuum gap. We show that the enhancement mechanism of the HMM emitter is due to the coupled surface plasmon modes at multiple metal-dielectric interfaces inside the HMM emitter. With the minority carrier transport model, the optimal p-n junction depth of the TPV cell has also been determined at various vacuum gaps.
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Han S, Lee BJ. Electromagnetic resonance modes on a two-dimensional tandem grating and its application for broadband absorption in the visible spectrum. OPTICS EXPRESS 2016; 24:A202-A214. [PMID: 26832574 DOI: 10.1364/oe.24.00a202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this work, we numerically investigate the electromagnetic resonances on two-dimensional tandem grating structures. The base of a tandem grating consists of an opaque Au substrate, a SiO(2) spacer, and a Au grating (concave type); that is, a well-known fishnet structure forming Au/SiO(2)/Au stack. A convex-type Au grating (i.e., topmost grating) is then attached on top of the base fishnet structure with or without additional SiO(2) spacer, resulting in two types of tandem grating structures. In order to calculate the spectral reflectance and local magnetic field distribution, the finite-difference time-domain method is employed. When the topmost Au grating is directly added onto the base fishnet structure, the surface plasmon and magnetic polariton in the base structure are branched out due to the geometric asymmetry with respect to the SiO(2) spacer. If additional SiO(2) spacer is added between the topmost Au grating and the base fishnet structure, new magnetic resonance modes appear due to coupling between two vertically aligned Au/SiO(2)/Au stacks. With the understanding of multiple electromagnetic resonance modes on the proposed tandem grating structures, we successfully design a broadband absorber made of Au and SiO(2) in the visible spectrum.
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Ha J, Lee BJ, Hwang DJ, Kim D. Femtosecond laser nanowelding of silver nanowires for transparent conductive electrodes. RSC Adv 2016. [DOI: 10.1039/c6ra19608j] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Femtosecond laser irradiation enables local crystalline nanojoining of silver nanowires with minimizing thermal damage on flexible substrates.
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Lee BJ, Sukri NM, Ogden H, Vine C, Thake CD, Turner JE, Bilzon JLJ. A comparison of two commercially available ELISA methods for the quantification of human plasma heat shock protein 70 during rest and exercise stress. Cell Stress Chaperones 2015; 20:917-26. [PMID: 26111949 PMCID: PMC4595431 DOI: 10.1007/s12192-015-0610-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 06/01/2015] [Accepted: 06/04/2015] [Indexed: 10/23/2022] Open
Abstract
This study compared resting and exercise heat/hypoxic stress-induced levels of plasma extracellular heat shock protein 70 (eHSP70) in humans using two commercially available enzyme-linked immunosorbent assay (ELIS)A kits. EDTA plasma samples were collected from 21 males during two separate investigations. Participants in part A completed a 60-min treadmill run in the heat (HOT70; 33.0 ± 0.1 °C, 28.7 ± 0.8 %, n = 6) at 70 % V̇O2max. Participants in part B completed 60 min of cycling exercise at 50 % V̇O2max in either hot (HOT50; 40.5 °C, 25.4 relative humidity (RH)%, n = 7) or hypoxic (HYP50; fraction of inspired oxygen (FIO2) = 0.14, 21 °C, 35 % RH, n = 8) conditions. Samples were collected prior to and immediately upon termination of exercise and analysed for eHSP70 using EKS-715 high-sensitivity HSP70 ELISA and new ENZ-KIT-101 Amp'd(™) HSP70 high-sensitivity ELISA. ENZ-KIT was superior in detecting resting eHSP70 (1.54 ± 3.27 ng · mL(-1); range 0.08 to 14.01 ng · mL(-1)), with concentrations obtained from 100 % of samples compared to 19 % with EKS-715 assay. The ENZ-KIT requires optimisation prior to running samples in order to ensure participants fall within the standard curve, a step not required with EKS-715. Using ENZ-KIT, a 1:4 dilution allowed for quantification of resting HSP70 in 26/32 samples, with a 1:8 (n = 3) and 1:16 (n = 3) dilution required to determine the remaining samples. After exercise, eHSP70 was detected in 6/21 and 21/21 samples using EKS-715 and ENZ-KIT, respectively. eHSP70 was increased from rest after HOT70 (p < 0.05), but not HOT50 (p > 0.05) or HYP50 (p > 0.05) when analysed using ENZ-KIT. It is recommended that future studies requiring the precise determination of resting plasma eHSP70 use the ENZ-KIT (i.e. HSP70 Amp'd(®) ELISA) instead of the EKS-715 assay, despite additional assay development time and cost required.
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Kim JH, Kim YS, Cho GS, Kim NH, Gong CH, Lee BJ, Jang YJ. Human Rhinovirus-induced Proinflammatory Cytokine and Interferon-β Responses in Nasal Epithelial Cells From Chronic Rhinosinusitis Patients. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2015; 7:489-96. [PMID: 26122508 PMCID: PMC4509662 DOI: 10.4168/aair.2015.7.5.489] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 02/27/2015] [Accepted: 03/27/2015] [Indexed: 12/14/2022]
Abstract
Purpose Asthma exacerbation from human rhinovirus (HRV) infection is associated with deficient antiviral interferon (IFN) secretion. Although chronic rhinosinusitis (CRS), an inflammatory upper airway disease, is closely linked to asthma, IFN-β responses to HRV infections in human nasal epithelial cells (HNECs) from CRS patients remain to be studied. We evaluated inflammatory and antiviral responses to HRV infection in HNECs from CRS patients. Methods HNECs, isolated from turbinate tissue of 13 patients with CRS and 14 non-CRS controls, were infected with HRV16 for 4 hours. The HRV titer, LDH activity, production of proinflammatory cytokines and IFN-β proteins, and expression levels of RIG-I and MDA5 mRNA were assessed at 8, 24, and 48 hours after HRV16 infection. Results The reduction in viral titer was slightly delayed in the CRS group compared to the non-CRS control group. IL-6 and IL-8 were significantly increased to a similar extent in both groups after HRV infection. In the control group, IFN-β production and MDA5 mRNA expression were significantly increased at 8 and 24 hours after HRV16 infection, respectively. By contrast, in the CRS group, IFN-β was not induced by HRV infection; however, HRV-induced MDA5 mRNA expression was increased, but the increase was slightly delayed compared to the non-CRS control group. The RIG-I mRNA level was not significantly increased by HRV16 infection in either group. Conclusions HRV-induced secretion of proinflammatory cytokines in CRS patients was not different from that in the non-CRS controls. However, reductions in viral titer, IFN-β secretion, and MDA5 mRNA expression in response to HRV infection in CRS patients were slightly impaired compared to those in the controls, suggesting that HRV clearance in CRS patients might be slightly deficient.
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Lim M, Jin S, Lee SS, Lee BJ. Graphene-assisted Si-InSb thermophotovoltaic system for low temperature applications. OPTICS EXPRESS 2015; 23:A240-A253. [PMID: 25968790 DOI: 10.1364/oe.23.00a240] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The present work theoretically analyzes the performance of the near-field thermophotovoltaic (TPV) energy conversion device for low temperature applications (Tsource ∼ 500 K). In the proposed TPV system, doped Si is employed as the source because its optical property can be readily tuned by changing the doping concentration, and InSb is selected as a TPV cell because of its low bandgap energy (0.17 eV). In order to enhance the near-field thermal radiation between the source and the TPV cell, monolayer of graphene is coated on the cell side so that surface plasmon can play a critical role in heat transfer. It is found that monolayer of graphene can significantly enhance the power throughput by 30 times and the conversion efficiency by 6.1 times compared to the case without graphene layer. The resulting maximum conversion efficiency is 19.4% at 10-nm vacuum gap width.
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Lee SD, Lee BJ, Park JJ, Kim JS, Bak YT. Education and imaging. Gastrointestinal: Impacted gastric balloon in small bowel. J Gastroenterol Hepatol 2015; 30:1. [PMID: 25536457 DOI: 10.1111/jgh.12825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Yeo J, Kim G, Hong S, Lee J, Kwon J, Lee H, Park H, Manoroktul W, Lee MT, Lee BJ, Grigoropoulos CP, Ko SH. Single nanowire resistive nano-heater for highly localized thermo-chemical reactions: localized hierarchical heterojunction nanowire growth. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:5015-5022. [PMID: 25168280 DOI: 10.1002/smll.201401427] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/30/2014] [Indexed: 06/03/2023]
Abstract
A single nanowire resistive nano-heater (RNH) is fabricated, and it is demonstrated that the RNH can induce highly localized temperature fields, which can trigger highly localized thermo-chemical reactions to grow hierarchical nanowires directly at the desired specific spot such as ZnO nanowire branch growth on a single Ag nanowire.
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Kim ES, Lee BJ, Lee GW, Jung A, Hwang HS. Health Status in Adult Patients with Copd in Korea. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A779-A780. [PMID: 27202887 DOI: 10.1016/j.jval.2014.08.368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Jeon J, Park S, Lee BJ. Optical property of blended plasmonic nanofluid based on gold nanorods. OPTICS EXPRESS 2014; 22 Suppl 4:A1101-A1111. [PMID: 24978073 DOI: 10.1364/oe.22.0a1101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Present work experimentally characterizes the optical property of blended plasmonic nanofuids based on gold nanorod (AuNR) with different aspect ratios. The existence of localized surface plasmon resonance was verified from measured extinction coefficient of three AuNR solutions, and spectral tunability of AuNR nanofluid was successfully demonstrated in the visible and near-infrared spectral region. The representative aspect ratio and volume fraction of each sample were then calculated from the relation between extinction coefficient and extinction efficiency, which leads to the design of a blended plasmonic nanofluid having broad-band absorption characteristic in the visible and near-infrared spectral region. The results obtained from this study will facilitate the development of a novel volumetric solar thermal collectors using plasmonic nanofluids.
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Park H, Lee BJ, Lee J. Note: Simultaneous determination of local temperature and thickness of heated cantilevers using two-wavelength thermoreflectance. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:036109. [PMID: 24689637 DOI: 10.1063/1.4869079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this work, we have demonstrated that two-wavelength thermoreflectance technique can be used to characterize the local thickness and temperature of heated cantilevers at steady-state operation. By taking the ratio of reflectances for two lasers with different wavelengths, the geometrical factor causing the mismatch between experimentally measured and theoretically calculated reflectances was eliminated. Based on the fitting analysis of the reflectance ratio of two wavelengths at various input powers to the heated cantilevers, the local temperature and thickness could be unambiguously determined.
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Lim M, Lee SS, Lee BJ. Near-field thermal radiation between graphene-covered doped silicon plates. OPTICS EXPRESS 2013; 21:22173-22185. [PMID: 24104109 DOI: 10.1364/oe.21.022173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The present work describes a theoretical investigation of the near-field thermal radiation between doped Si plates coated with a mono-layer of graphene. It is found that the radiative heat flux between doped Si plates can be either enhanced or suppressed by introducing graphene layer, depending on the Si doping concentration and chemical potential of graphene. Graphene can enhance the heat flux if it matches resonance frequencies of surface plasmon at vacuum-source and vacuum-receiver interfaces. In particular, significant enhancement is achieved when graphene is coated on both surfaces that originally does not support the surface plasmon resonance. The results obtained in this study provide an important guideline into enhancing the near-field thermal radiation between doped Si plates by introducing graphene.
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Kang JM, Chung JY, Han JH, Kim YS, Lee BJ, Yi JW. Anesthetic management of a patient with Huntington's chorea -A case report-. Korean J Anesthesiol 2013; 64:262-4. [PMID: 23560194 PMCID: PMC3611078 DOI: 10.4097/kjae.2013.64.3.262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/11/2012] [Accepted: 06/12/2012] [Indexed: 11/21/2022] Open
Abstract
Huntington's chorea is a rare hereditary disorder of the nervous system. It is inherited as an autosomal dominant disorder and is characterized by progressive chorea, dementia and psychiatric disturbances. The best anesthetic technique is yet to be established for these patients with increased risk of aspiration due to involvement of pharyngeal muscles and an exaggerated response to sodium thiopental and succinylcholine. The primary goal in general anesthesia for these patients is to provide airway protection and a rapid and safe recovery. We report the anesthetic management of a 51-year-old patient with Huntington's chorea admitted for an emergency operation.
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Kim J, Han S, Walsh T, Park K, Jae Lee B, King WP, Lee J. Temperature measurements of heated microcantilevers using scanning thermoreflectance microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:034903. [PMID: 23556839 DOI: 10.1063/1.4797621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report the development of scanning thermoreflectance thermometry and its application for steady and dynamic temperature measurement of a heated microcantilever. The local thermoreflectance signal of the heated microcantilever was calibrated to temperature while the cantilever was under steady and periodic heating operation. The temperature resolution of our approach is 0.6 K, and the spatial resolution is 2 μm, which are comparable to micro-Raman thermometry. However, the temporal resolution of our approach is about 10 μsec, which is significantly faster than micro-Raman thermometry. When the heated microcantilever is periodically heated with frequency up to 100 kHz, we can measure both the in-phase and out-of-phase components of the temperature oscillation. For increasing heating frequency, the measured cantilever AC temperature distribution tends to be confined in the vicinity of the heater region and becomes increasingly out of phase with the driving signal. These results compare well with finite element simulations.
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Lee J, Lee BJ, Yoon HI, Lee CT, Lee JH. Influence of previous tuberculosis treatment history on acid-fast bacilli smear and culture conversion. Int J Tuberc Lung Dis 2013; 16:1344-8. [PMID: 23107634 DOI: 10.5588/ijtld.12.0113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING A teaching hospital in the Republic of Korea, 2003-2009. OBJECTIVE To evaluate the effect of previous tuberculosis (TB) treatment history on sputum smear and culture conversion. DESIGN Data, including sputum acid-fast bacilli (AFB) results at baseline and at weeks 2, 4, 8, 12, 16, 20 and 24, were collected from patients with AFB sputum smear-positive and culture-confirmed pulmonary TB. Patients with multidrug-resistant TB or those with poor adherence were excluded. AFB conversion was compared between patients with a previous history of anti-tuberculosis treatment and those without. RESULTS The median age of the 208 patients was 49.0 years; 58.3% were male, while 43 (20.7%) had a history of previous anti-tuberculosis treatment. Patients with a history of previous treatment had significantly lower sputum smear-negative conversion at 2 weeks of treatment compared with patients without (70.0% vs. 44.8%, P = 0.005). However, the two groups did not differ in culture conversion and in smear conversion at 4, 8, 12, 16, 20 and 24 weeks of anti-tuberculosis treatment. CONCLUSION Patients with a history of previous anti-tuberculosis treatment are more likely to have positive sputum AFB smear at 2 weeks of treatment. However, sputum culture conversion is not affected by previous treatment history.
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Ding B, Yang M, Lee BJ, Lee JK. Tunable surface plasmons of dielectric core-metal shell particles for dye sensitized solar cells. RSC Adv 2013. [DOI: 10.1039/c3ra41714j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Yun JW, Park JJ, Kim KH, Noh HJ, Kwon MJ, Lee SY, Joo MK, Lee BJ, Kim JS, Bak YT. Successful endoscopic submucosal dissection for triple sporadic nonampullary duodenal adenomas using a "push and peel off" technique. Endoscopy 2012; 44 Suppl 2 UCTN:E25-6. [PMID: 22396260 DOI: 10.1055/s-0031-1291504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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