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Sakai K, Fuke H, Yoshimura K, Sasaki M, Abe K, Haino S, Hams T, Hasegawa M, Kim KC, Lee MH, Makida Y, Mitchell JW, Nishimura J, Nozaki M, Orito R, Ormes JF, Seo ES, Streitmatter RE, Thakur N, Yamamoto A, Yoshida T. Search for Antideuterons of Cosmic Origin Using the BESS-Polar II Magnetic-Rigidity Spectrometer. Phys Rev Lett 2024; 132:131001. [PMID: 38613296 DOI: 10.1103/physrevlett.132.131001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 10/21/2023] [Accepted: 01/10/2024] [Indexed: 04/14/2024]
Abstract
We searched for antideuterons (d[over ¯]'s) in the 4.7×10^{9} cosmic-ray events observed during the BESS-Polar II flight at solar minimum in 2007-2008 but found no candidates. The resulting 95% C.L. upper limit on the d[over ¯] flux is 6.7×10^{-5} (m^{2} s sr GeV/n)^{-1} in an energy range from 0.163 to 1.100 GeV/n. The result has improved by more than a factor of 14 from the upper limit of BESS97, which had a potential comparable to that of BESS-Polar II in the search for cosmic-origin d[over ¯]'s and was conducted during the former solar minimum. The upper limit of d[over ¯] flux from BESS-Polar II is the first result achieving the sensitivity to constrain the latest theoretical predictions.
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Affiliation(s)
- K Sakai
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
- Center for Research and Exploration in Space Science and Technology (CRESST)
| | - H Fuke
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210, Japan
| | - K Yoshimura
- Okayama University, Okayama, Okayama 700-8530, Japan
| | - M Sasaki
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
- Center for Research and Exploration in Space Science and Technology (CRESST)
| | - K Abe
- Kobe University, Kobe, Hyogo 657-8501, Japan
| | - S Haino
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Hams
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
- Center for Research and Exploration in Space Science and Technology (CRESST)
| | - M Hasegawa
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - K C Kim
- IPST, University of Maryland, College Park, Maryland 20742, USA
| | - M H Lee
- IPST, University of Maryland, College Park, Maryland 20742, USA
| | - Y Makida
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - J W Mitchell
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
| | - J Nishimura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210, Japan
- The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - M Nozaki
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - R Orito
- Kobe University, Kobe, Hyogo 657-8501, Japan
| | - J F Ormes
- University of Denver, Denver, Colorado 80208, USA
| | - E S Seo
- IPST, University of Maryland, College Park, Maryland 20742, USA
| | - R E Streitmatter
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
| | - N Thakur
- NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA
| | - A Yamamoto
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Yoshida
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210, Japan
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Hajiaghaei Tabalvandani A, Norouzi M, Kayhani MH, Komeili Birjandi A, Emamian A, Kim M, Kim KC. A general analytical solution for fluid flow and heat convection through arbitrary-shaped triangular ducts: A variational analysis. Heliyon 2024; 10:e25293. [PMID: 38379984 PMCID: PMC10877169 DOI: 10.1016/j.heliyon.2024.e25293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 01/17/2024] [Accepted: 01/24/2024] [Indexed: 02/22/2024] Open
Abstract
This paper presents an analytical solution for fluid flow and heat transfer inside arbitrarily-shaped triangular ducts for the first time. The former analytical solutions are limited to the special case of isosceles triangular ducts. The literature has no report about the analytical solution for the general case of arbitrarily-shaped triangular ducts. Due to the significant role of fluid flow through non-circular channels in industry and the large number of triangular shapes, a method for solving the heat transfer problem for all triangular shapes is needed. The heat transfer of a fluid flow through a channel with an arbitrary triangular cross-section for the case of constant heat flux at the walls is solved in this work for the first time, considering viscous dissipation. Here, the functionals of flow and heat transfer equations are derived, and the resulting Euler-Lagrange equations are solved using the Ritz method. The effect of the duct geometry on the velocity profile and friction coefficient is studied in detail. The effect of the Brinkman number on the temperature distribution and Nusselt number is investigated for both cooling and heating cases. The results reveal that the critical Brinkman Number distinguishes between the cooling and heating cases and represents the critical point at which the Nusselt number approaches infinity. The value of the Nusselt number decreases with the increase of the Brinkman number in both the wall cooling and heating modes. It is also found that the equilateral triangle exhibits the minimum friction coefficient and the maximum value of the Poiseuille number.
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Affiliation(s)
| | - Mahmood Norouzi
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | | | - Amir Komeili Birjandi
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Amin Emamian
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
- Department of Mechanical Engineering, University of Bojnord, Bojnord, Iran
| | - Mirae Kim
- School of Mechanical Engineering, Eco-friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, 46241, Republic of Korea
| | - Kyung Chun Kim
- School of Mechanical Engineering, Eco-friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, 46241, Republic of Korea
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Abbaspur A, Norouzi M, Akbarzadeh P, Vaziri SA, Sharghi MM, Kim KC, Kim M. An analytical study on nonlinear viscoelastic lubrication in journal bearings. Sci Rep 2023; 13:16836. [PMID: 37803195 PMCID: PMC10558581 DOI: 10.1038/s41598-023-43712-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 09/27/2023] [Indexed: 10/08/2023] Open
Abstract
This paper presents a novel analytical solution for journal-bearing viscoelastic lubrication using the perturbation method. The nonlinear Giesekus model was used for the constitutive equations to study the effects of fluid elasticity, shear-thinning viscometric functions, and strain-hardening elongational viscosity of viscoelastic lubrication. The investigation focuses on the impact of characteristic parameters such as mobility factor, eccentricity ratio, and Weissenberg number on the fluid film pressure distribution, load capacity, and shear stress. Although distinguishing between the normal stress differences and extensional viscosity in mixed viscoelastic flows is complicated, we investigated the role and contribution of these two factors. By increasing the elasticity of the fluid, the portion of both mentioned parameters increases consequently. Furthermore, analyses and comparisons show the contributions of the first normal stress and elongational viscosity to the load capacity of the bearing through the stress ratio and flow type parameter for the first time. The research findings indicate that fluid elasticity enhances the load capacity of the bearing compared to a Newtonian lubricant with the same effective viscosity. Moreover, the bearing load capacity is divided into two regions. In the linear region, the mobility factor and Weissenberg numbers have minimal effects leading to a linear increase in the load distribution, and in the exponential region, the load capacity changes are considerable. This research provides valuable insights into the behavior of viscoelastic lubrication in journal-bearing systems.
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Affiliation(s)
- Ali Abbaspur
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Mahmood Norouzi
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Pooria Akbarzadeh
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | | | | | - Kyung Chun Kim
- School of Mechanical Engineering, Eco-Friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, Republic of Korea
| | - Mirae Kim
- School of Mechanical Engineering, Eco-Friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, Republic of Korea.
- Rolls-Royce University Technology Center, Pusan National University, Busan, Republic of Korea.
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Rezaie MR, Norouzi M, Kayhani MH, Taghavi SM, Kim M, Kim KC. On viscoelastic drop impact onto thin films: axisymmetric simulations and experimental analysis. Sci Rep 2023; 13:11041. [PMID: 37419954 DOI: 10.1038/s41598-023-38235-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 07/05/2023] [Indexed: 07/09/2023] Open
Abstract
This study investigates the effect of fluid elasticity on axisymmetric droplets colliding with pre-existing liquid films, using both numerical and experimental approaches. The numerical simulations involve solving the incompressible flow momentum equations with viscoelastic constitutive laws using the finite volume method and the volume of fluid (VOF) technique to track the liquid's free surface. Here, the Oldroyd-B model is used as the constitutive equation for the viscoelastic phase. Experiments are also performed for dilute viscoelastic solutions with 0.005% and 0.01% (w/w) polyacrylamide in 80:20 glycerin/water solutions, in order to ensure the validity of the numerical solution and to investigate the elasticity effect. The formation and temporal evolution of the crown parameters are quantified by considering the flow parameters, including the fluid's elasticity. The results indicate that the axisymmetric numerical solutions reasonably agree with the experimental observations. Generally, the fluid's elasticity can enlarge the crown dimension at different thicknesses of the fluid film. Moreover, at intermediate values of the Weissenberg number, the extensional force in the crown wall can control the crown propagation. Furthermore, the results reveal that the effects of the Weber number and the viscosity ratio on this problem are more significant at higher values of the Weissenberg number.
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Affiliation(s)
- M R Rezaie
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - M Norouzi
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - M H Kayhani
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - S M Taghavi
- Chemical Engineering Department, Laval University, Quebec, G1V 0A6, Canada
| | - Mirae Kim
- Rolls-Royce and Pusan National University Technology Center, Pusan National University, Busan, Republic of Korea.
| | - Kyung Chun Kim
- School of Mechanical Engineering, Eco-friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, 46241, Republic of Korea.
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Mathew S, Hosseinirad E, Kim KC, Chung WS, Li OL, Cho YR. Enhanced electrocatalytic water splitting by Sm and Gd-doped ceria electrocatalysts on Ni foam substrate. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Affiliation(s)
- Sobin Mathew
- Division of Materials Science and Engineering Pusan National University Busan 46241, Republic of Korea
| | - Chan Yang Kim
- Division of Materials Science and Engineering Pusan National University Busan 46241, Republic of Korea
| | - Min‐Kyun Kim
- Division of Materials Science and Engineering Pusan National University Busan 46241, Republic of Korea
| | - Kyung Chun Kim
- School of Mechanical Engineering Pusan National University Busan 46241, Republic of Korea
| | - Won Sub Chung
- Division of Materials Science and Engineering Pusan National University Busan 46241, Republic of Korea
| | - Young‐Rae Cho
- Division of Materials Science and Engineering Pusan National University Busan 46241, Republic of Korea
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Bashtani I, Esfahani JA, Kim KC. Effects of water-aluminum oxide nanofluid on double pipe heat exchanger with gear disc turbulators: A numerical investigation. J Taiwan Inst Chem Eng 2021. [DOI: 10.1016/j.jtice.2021.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Kim Y, Moon C, Nematollahi O, Kim HD, Kim KC. Time-Resolved PIV Measurements and Turbulence Characteristics of Flow Inside an Open-Cell Metal Foam. Materials (Basel) 2021; 14:ma14133566. [PMID: 34202204 PMCID: PMC8269601 DOI: 10.3390/ma14133566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/06/2021] [Accepted: 06/22/2021] [Indexed: 11/16/2022]
Abstract
Open-cell metal foams are porous medium for thermo-fluidic systems. However, their complex geometry makes it difficult to perform time-resolved (TR) measurements inside them. In this study, a TR particle image velocimetry (PIV) method is introduced for use inside open-cell metal foam structures. Stereolithography 3D printing methods and conventional post-processing methods cannot be applied to metal foam structures; therefore, PolyJet 3D printing and post-processing methods were employed to fabricate a transparent metal foam replica. The key to obtaining acceptable transparency in this method is the complete removal of the support material from the printing surfaces. The flow characteristics inside a 10-pore-per-inch (PPI) metal foam were analyzed in which porosity is 0.92 while laminar flow condition is applied to inlet. The flow inside the foam replica is randomly divided and combined by the interconnected pore network. Robust crosswise motion occurs inside foam with approximately 23% bulk speed. Strong influence on transverse motion by metal foam is evident. In addition, span-wise vorticity evolution is similar to the integral time length scale of the stream-wise center plane. The span-wise vorticity fluctuation through the foam arrangement is presented. It is believed that this turbulent characteristic is caused by the interaction of jets that have different flow directions inside the metal foam structure. The finite-time Lyapunov exponent method is employed to visualize the vortex ridges. Fluctuating attracting and repelling material lines are expected to enhance the heat and mass transfer. The results presented in this study could be useful for understanding the flow characteristics inside metal foams.
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Affiliation(s)
- Youngwoo Kim
- School of Mechanical Engineering, Pusan National University, Busan 46241, Korea; (Y.K.); (C.M.); (O.N.)
| | - Chanhee Moon
- School of Mechanical Engineering, Pusan National University, Busan 46241, Korea; (Y.K.); (C.M.); (O.N.)
| | - Omid Nematollahi
- School of Mechanical Engineering, Pusan National University, Busan 46241, Korea; (Y.K.); (C.M.); (O.N.)
| | - Hyun Dong Kim
- Rolls-Royce and Pusan National University Technology Centre, Pusan National University, Busan 46241, Korea
- Correspondence: (H.D.K.); (K.C.K.); Tel.: +82-51-510-1536 (H.D.K.); +82-51-510-2324 (K.C.K.)
| | - Kyung Chun Kim
- School of Mechanical Engineering, Pusan National University, Busan 46241, Korea; (Y.K.); (C.M.); (O.N.)
- Correspondence: (H.D.K.); (K.C.K.); Tel.: +82-51-510-1536 (H.D.K.); +82-51-510-2324 (K.C.K.)
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Nematollahi O, Samsam-Khayani H, Nili-Ahmadabadi M, Yoon SY, Kim KC. A novel self-seeding method for particle image velocimetry measurements of subsonic and supersonic flows. Sci Rep 2020; 10:10834. [PMID: 32616771 PMCID: PMC7331811 DOI: 10.1038/s41598-020-67680-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/12/2020] [Indexed: 11/12/2022] Open
Abstract
A self-seeding particle method is proposed for particle image velocimetry measurements in closed cycles such as Organic Rankine Cycles. Condensed droplets of vapor are used as tracers in a closed cycle for both subsonic and supersonic regimes. A free jet of R245fa in the vapor phase is examined in a case study with two different nozzle pressure ratios of 5.1 and 2.1 to evaluate the tracer particles in both supersonic and subsonic conditions. A simple turbulent jet in subsonic conditions and an under-expanded jet are observed in high supersonic conditions. The flow structures of the under-expanded jet are captured using the proposed method, and vivid images of the Mach disk and shock cells are obtained. A series of Schlieren photography experiments are performed to validate the proposed method. The results show that the method can be a good candidate for tracer particles in the closed cycles where condensation of the working fluid is possible.
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Affiliation(s)
- Omid Nematollahi
- School of Mechanical Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Hadi Samsam-Khayani
- School of Mechanical Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Mahdi Nili-Ahmadabadi
- Department of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Sang Youl Yoon
- Rolls-Royce and Pusan National University Technology Centre, Pusan National University, Busan, 46241, Republic of Korea.
| | - Kyung Chun Kim
- School of Mechanical Engineering, Pusan National University, Busan, 46241, Republic of Korea.
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Kim D, Ma Y, Kim KC. Three-dimensional particle behavior using defocusing method in micro-toroidal vortex generated by optoelectrokinetic flow. J Vis (Tokyo) 2018. [DOI: 10.1007/s12650-018-0480-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Eck TF, Holben BN, Reid JS, Xian P, Giles DM, Sinyuk A, Smirnov A, Schafer JS, Slutsker I, Kim J, Koo JH, Choi M, Kim KC, Sano I, Arola A, Sayer AM, Levy RC, Munchak LA, O'Neill NT, Lyapustin A, Hsu NC, Randles CA, Da Silva AM, Buchard V, Govindaraju RC, Hyer E, Crawford JH, Wang P, Xia X. Observations of the Interaction and Transport of Fine Mode Aerosols with Cloud and/or Fog in Northeast Asia from Aerosol Robotic Network (AERONET) and Satellite Remote Sensing. J Geophys Res Atmos 2018; 123:5560-5587. [PMID: 32661496 PMCID: PMC7356674 DOI: 10.1029/2018jd028313] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/26/2018] [Indexed: 06/10/2023]
Abstract
Analysis of sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in mid-visible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological co-variation with atmospheric stability and convergence. The new development of Aerosol Robotic network (AERONET) Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the Spectral Deconvolution Algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter-summer period, comparisons of AERONET L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.
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Affiliation(s)
- T F Eck
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Universities Space Research Association, Columbia, MD, USA
| | - B N Holben
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J S Reid
- Naval Research Laboratory, Monterey, CA, USA
| | - P Xian
- Naval Research Laboratory, Monterey, CA, USA
| | - D M Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - A Sinyuk
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - A Smirnov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - J S Schafer
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - I Slutsker
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - J Kim
- Yonsei University, Seoul, South Korea
| | - J-H Koo
- Yonsei University, Seoul, South Korea
| | - M Choi
- Yonsei University, Seoul, South Korea
| | - K C Kim
- Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - I Sano
- Kinki University, Osaka, Japan
| | - A Arola
- Finnish Meteorological Institute, Kuopio, Finland
| | - A M Sayer
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Universities Space Research Association, Columbia, MD, USA
| | - R C Levy
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Munchak
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - A Lyapustin
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - N C Hsu
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - C A Randles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A M Da Silva
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - V Buchard
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Universities Space Research Association, Columbia, MD, USA
| | - R C Govindaraju
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Science Systems Applications, Inc., Lanham, MD, USA
| | - E Hyer
- Naval Research Laboratory, Monterey, CA, USA
| | | | - P Wang
- LAGEO, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - X Xia
- LAGEO, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
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Hong H, Ji HS, Kim HD, Kim KC. Temporal and spatial flow structures in a simulated vessel with stenotic lesion using time-resolved PIV technique. J Vis (Tokyo) 2017. [DOI: 10.1007/s12650-017-0432-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kim D, Yi SJ, Kim HD, Kim KC. Simultaneous measurement of temperature and velocity fields using thermographic phosphor tracer particles. J Vis (Tokyo) 2016. [DOI: 10.1007/s12650-016-0394-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ji HS, Qiang L, Beak JH, Mieremet R, Kim KC. Effect of the wind direction on the near wake structures of an Archimedes spiral wind turbine blade. J Vis (Tokyo) 2016. [DOI: 10.1007/s12650-016-0356-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cha SM, Shin HD, Kim KC, Park IY. Extensive curettage using a high-speed burr versus dehydrated alcohol instillation for the treatment of enchondroma of the hand. J Hand Surg Eur Vol 2015; 40:384-91. [PMID: 24369364 DOI: 10.1177/1753193413517204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 11/22/2013] [Indexed: 02/03/2023]
Abstract
The purpose of this retrospective study was to compare the clinical and radiological outcomes of patients treated with different adjuvant methods after curettage for enchondromas of the hand. Sixty-two patients with enchondroma were treated with high-speed burring (29 patients) or alcohol instillation (33 patients) after curettage. The mean follow-up was 40.8 months. No significant differences in the visual analogue scale, Disabilities of the Arm, Shoulder, and Hand scores, total range of active motion, grip strength, and complete healing time were observed between the groups. The distribution of the results of the formula by Wilhelm and Feldmeier were not significantly different between the groups. No surgery-related complications, postoperative pathological fractures, or recurrence was found in either group. For the treatment of enchondroma in the metacarpal and proximal phalanx, alcohol instillation immediately after curettage was as effective as extensive curettage using a high-speed burr.
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Affiliation(s)
- S M Cha
- Department of Orthopaedic Surgery, Regional Rheumatoid and Degenerative Arthritis Center, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Korea
| | - H D Shin
- Department of Orthopaedic Surgery, Regional Rheumatoid and Degenerative Arthritis Center, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Korea
| | - K C Kim
- Department of Orthopaedic Surgery, Regional Rheumatoid and Degenerative Arthritis Center, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Korea
| | - I Y Park
- Department of Orthopaedic Surgery, Regional Rheumatoid and Degenerative Arthritis Center, Chungnam National University Hospital, Chungnam National University School of Medicine, Daejeon, Korea
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Kim D, Shim J, Chuang HS, Kim KC. Numerical simulation on the opto-electro-kinetic patterning for rapid concentration of particles in a microchannel. Biomicrofluidics 2015; 9:034102. [PMID: 26015839 PMCID: PMC4433480 DOI: 10.1063/1.4921232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/06/2015] [Indexed: 05/04/2023]
Abstract
This paper presents a mathematical model for laser-induced rapid electro-kinetic patterning (REP) to elucidate the mechanism for concentrating particles in a microchannel non-destructively and non-invasively. COMSOL(®)(v4.2a) multiphysics software was used to examine the effect of a variety of parameters on the focusing performance of the REP. A mathematical model of the REP was developed based on the AC electrothermal flow (ACET) equations, the dielectrophoresis (DEP) equation, the energy balance equation, the Navier-Stokes equation, and the concentration-distribution equation. The medium was assumed to be a diluted solute, and different electric potentials and laser illumination were applied to the desired place. Gold (Au) electrodes were used at the top and bottom of a microchannel. For model validation, the simulation results were compared with the experimental data. The results revealed the formation of a toroidal microvortex via the ACET effect, which was generated due to laser illumination and joule-heating in the area of interest. In addition, under some conditions, such as the frequency of AC, the DEP velocity, and the particle size, the ACET force enhances and compresses resulting in the concentration of particles. The conditions of the DEP velocity and the ACET velocity are presented in detail with a comparison of the experimental results.
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Affiliation(s)
- Dong Kim
- School of Mechanical Engineering, Pusan National University , Busan 609-735, South Korea
| | - Jaesool Shim
- School of Mechanical Engineering, Yeungnam University , Gyeongsan 712-749, South Korea
| | - Han-Sheng Chuang
- Department of Biomedical Engineering, National Cheng Kung University , Tainan, Taiwan
| | - Kyung Chun Kim
- School of Mechanical Engineering, Pusan National University , Busan 609-735, South Korea
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Kim DY, Kim HD, Kim KC. Visualization study on the behaviors of oscillating liquid bridge between two parallel plates with surface treatments. J Vis (Tokyo) 2015. [DOI: 10.1007/s12650-015-0285-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Baral S, Kim KC. Simulation, Validation and Economic Analysis of Solar Powered Organic Rankine Cycle for Electricity Generation. ACTA ACUST UNITED AC 2015. [DOI: 10.7763/jocet.2015.v3.170] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Kim HD, Yi SJ, Kim KC. Photo-bleaching characteristics of oxygen-sensitive particles. J Vis (Tokyo) 2014. [DOI: 10.1007/s12650-014-0244-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Wang KC, Kumar A, Williams SJ, Green NG, Kim KC, Chuang HS. An optoelectrokinetic technique for programmable particle manipulation and bead-based biosignal enhancement. Lab Chip 2014; 14:3958-67. [PMID: 25109364 DOI: 10.1039/c4lc00661e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Technologies that can enable concentration of low-abundance biomarkers are essential for early diagnosis of diseases. In this study, an optoelectrokinetic technique, termed Rapid Electrokinetic Patterning (REP), was used to enable dynamic particle manipulation in bead-based bioassays. Various manipulation capabilities, such as micro/nanoparticle aggregation, translation, sorting and patterning, were developed. The technique allows for versatile multi-parameter (voltage, light intensity and frequency) based modulation and dynamically addressable manipulation with simple device fabrication. Signal enhancement of a bead-based bioassay was demonstrated using dilute biotin-fluorescein isothiocyanate (FITC) solutions mixed with streptavidin-conjugated particles and rapidly concentrated with the technique. As compared with a conventional ELISA reader, the REP-enabled detection achieved a minimal readout of 3.87 nM, which was a 100-fold improvement in sensitivity. The multi-functional platform provides an effective measure to enhance detection levels in more bead-based bioassays.
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Affiliation(s)
- Kuan-Chih Wang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.
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Baral S, Kim KC. Thermodynamic Modeling of the Solar Organic Rankine Cycle with Selected Organic Working Fluids for Cogeneration. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/21563306.2014.10879015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Hyun YJ, Piao MJ, Kim KC, Zheng J, Yao CW, Cha JW, Kang HK, Yoo ES, Koh YS, Lee NH, Ko MH, Hyun JW. Photoprotective Effect of a <i>Polyopes affinis</i> (Harvey) Kawaguchi and Wang (<i>Halymeniaceae</i>)-Derived Ethanol Extract on Human Keratinocytes. TROP J PHARM RES 2014. [DOI: 10.4314/tjpr.v13i6.6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Sung T, Kim KH, Han S, Kim KC. Thermodynamic Analysis on Hybrid Turbo Expander - Heat Pump System for Natural Gas Pressure Regulation. ACTA ACUST UNITED AC 2014. [DOI: 10.7842/kigas.2014.18.4.13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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24
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Lee CH, Kim DY, Kim HD, Kim KC. Dynamic behavior and micro-explosion characteristics of impinging droplets on a high-temperature surface. J Vis (Tokyo) 2014. [DOI: 10.1007/s12650-014-0218-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Kim D, Yi SJ, Kim HD, Kim KC. Visualization study on the transient liquid film behavior and inner gas flow after rupture of a soap bubble. J Vis (Tokyo) 2014. [DOI: 10.1007/s12650-014-0217-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Chung DY, Kim KC. Association between shortened cervical length at 34-36 weeks' gestation and term labour in Asian women. J OBSTET GYNAECOL 2014; 34:153-5. [PMID: 24456436 DOI: 10.3109/01443615.2013.834303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Cervical length was measured at 34-36 weeks' gestation by transvaginal ultrasound. The purpose of measurement of cervical length before term was to reveal the association with the onset of term labour. This was a retrospective study of 362 women who were delivered at term at Mizmedi hospital, between August 2006 and November 2011. There was significant linear correlation between cervical length and the scan-to-labour interval in women with labour before 41 weeks. The measurement of cervical length at 34-36 weeks' gestation might be helpful in predicting the onset of term labour before 41 weeks.
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Affiliation(s)
- D Y Chung
- Department of Obstetrics and Gynecology
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Lee IS, Yook JH, Park YS, Kim KC, Oh ST, Kim BS. Suitability of endoscopic submucosal dissection for treatment of submucosal gastric cancers. Br J Surg 2013; 100:668-73. [PMID: 23334982 DOI: 10.1002/bjs.9051] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2012] [Indexed: 12/20/2022]
Abstract
BACKGROUND Endoscopic submucosal dissection (ESD) is not considered appropriate for all submucosal cancers owing to the risk of lymph node metastasis and difficulty estimating the deep margin status. This study aimed to determine predictive factors for lymph node metastases in submucosal cancer and to explore in which patients ESD might be feasible. METHODS Details of patients who had curative gastrectomy for submucosal gastric cancer at Asan Medical Centre from 2007 to 2011 were reviewed retrospectively to determine the relationship between lymph node metastasis and clinicopathological characteristics, including age, sex, tumour location, size, gross appearance, depth of invasion, histological type/differentiation, presence of lymphovascular/perineural invasion, and immunohistochemical staining results for p53, human epidermal growth factor receptor (HER) 1 and HER2. RESULTS A total of 1773 patients were analysed. The presence of lymphovascular invasion was related most strongly to lymph node metastasis. Multivariable analysis revealed that depth of invasion, tumour size, differentiation, gross appearance and perineural invasion were also related. Metastatic lymph nodes were found in four of 105 patients who met the classical criteria for ESD; all showed a moderately differentiated histological appearance. No lymph node metastases were observed in well differentiated SM1 tumours of any size (infiltration into upper third of submucosa), or in well differentiated SM2 (infiltration into middle third of submucosa) tumours of 2 cm or less without lymphovascular invasion. CONCLUSION Patients with well differentiated SM1 cancer of any size and those with well differentiated SM2 cancer of 2 cm or less without lymphovascular invasion may be suitable candidates for ESD.
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Affiliation(s)
- I S Lee
- Department of Surgery, Ulsan University College of Medicine and Asan Medical Centre, Seoul, Korea
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Abe K, Fuke H, Haino S, Hams T, Hasegawa M, Horikoshi A, Itazaki A, Kim KC, Kumazawa T, Kusumoto A, Lee MH, Makida Y, Matsuda S, Matsukawa Y, Matsumoto K, Mitchell JW, Myers Z, Nishimura J, Nozaki M, Orito R, Ormes JF, Sakai K, Sasaki M, Seo ES, Shikaze Y, Shinoda R, Streitmatter RE, Suzuki J, Takasugi Y, Takeuchi K, Tanaka K, Thakur N, Yamagami T, Yamamoto A, Yoshida T, Yoshimura K. Search for antihelium with the BESS-Polar spectrometer. Phys Rev Lett 2012; 108:131301. [PMID: 22540691 DOI: 10.1103/physrevlett.108.131301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Indexed: 05/31/2023]
Abstract
In two long-duration balloon flights over Antarctica, the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has searched for antihelium in the cosmic radiation with the highest sensitivity reported. BESS-Polar I flew in 2004, observing for 8.5 days. BESS-Polar II flew in 2007-2008, observing for 24.5 days. No antihelium candidate was found in BESS-Polar I data among 8.4×10(6) |Z|=2 nuclei from 1.0 to 20 GV or in BESS-Polar II data among 4.0×10(7) |Z|=2 nuclei from 1.0 to 14 GV. Assuming antihelium to have the same spectral shape as helium, a 95% confidence upper limit to the possible abundance of antihelium relative to helium of 6.9×10(-8)} was determined combining all BESS data, including the two BESS-Polar flights. With no assumed antihelium spectrum and a weighted average of the lowest antihelium efficiencies for each flight, an upper limit of 1.0×10(-7) from 1.6 to 14 GV was determined for the combined BESS-Polar data. Under both antihelium spectral assumptions, these are the lowest limits obtained to date.
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Affiliation(s)
- K Abe
- Kobe University, Kobe, Hyogo 657-8501, Japan
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Abe K, Fuke H, Haino S, Hams T, Hasegawa M, Horikoshi A, Kim KC, Kusumoto A, Lee MH, Makida Y, Matsuda S, Matsukawa Y, Mitchell JW, Nishimura J, Nozaki M, Orito R, Ormes JF, Sakai K, Sasaki M, Seo ES, Shinoda R, Streitmatter RE, Suzuki J, Tanaka K, Thakur N, Yamagami T, Yamamoto A, Yoshida T, Yoshimura K. Measurement of the cosmic-ray antiproton spectrum at solar minimum with a long-duration balloon flight over antarctica. Phys Rev Lett 2012; 108:051102. [PMID: 22400920 DOI: 10.1103/physrevlett.108.051102] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 10/21/2011] [Indexed: 05/31/2023]
Abstract
The energy spectrum of cosmic-ray antiprotons (p's) from 0.17 to 3.5 GeV has been measured using 7886 p's detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. This shows good consistency with secondary p calculations. Cosmologically primary p's have been investigated by comparing measured and calculated p spectra. BESS-Polar II data show no evidence of primary p's from the evaporation of primordial black holes.
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Affiliation(s)
- K Abe
- Kobe University, Kobe, Hyogo 657-8501, Japan
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Abstract
Mitochondrial DNA (mtDNA) variation has recently been suggested to have an association with athletic performance or physical endurance. Since mtDNA is haploid and lacks recombination, specific mutations in the mtDNA genome associated with human exercise tolerance or intolerance arise and remain in particular genetic backgrounds referred to as haplogroups. To assess the possible contribution of mtDNA haplogroup-specific variants to differences in elite athletic performance, we performed a population-based study of 152 Korean elite athletes [77 sprint/power athletes (SPA) and 75 endurance/middle-power athletes (EMA)] and 265 non-athletic controls (CON). The overall haplogroup distribution of EMA differed significantly from CON (p<0.01), but that of SPA did not. The EMA have an excess of haplogroups M* (OR 4.38, 95% CI 1.63-11.79, p=0.003) and N9 (OR 2.32, 95% CI 0.92-5.81, p=0.042), but a dearth of haplogroup B (OR 0.26, 95% CI 0.09-0.75, p=0.003) compared with the CON. Thus, our data imply that specific mtDNA lineages may provide a significant effect on elite Korean endurance status, although functional studies with larger sample sizes are necessary to further substantiate these findings.
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Affiliation(s)
- K C Kim
- Biological Sciences, Dankook University, Cheonan, Republic of Korea
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Batmunkh T, Kim YJ, Lee KY, Cayetano MG, Jung JS, Kim SY, Kim KC, Lee SJ, Kim JS, Chang LS, An JY. Time-resolved measurements of PM2.5 carbonaceous aerosols at Gosan, Korea. J Air Waste Manag Assoc 2011; 61:1174-1182. [PMID: 22168101 DOI: 10.1080/10473289.2011.609761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In order to better understand the characteristics of atmospheric carbonaceous aerosol at a background site in Northeast Asia, semicontinuous organic carbon (OC) and elemental carbon (EC), and time-resolved water-soluble organic carbon (WSOC) were measured by a Sunset OC/ EC and a PILS-TOC (particle-into-liquid sampler coupled with an online total organic carbon) analyzer, respectively, at the Gosan supersite on Jeju Island, Korea, in the summer (May 28-June 17) and fall (August 24-September 30) of 2009. Hourly average OC concentration varied in the range of approximately 0.87-28.38 microgC m-3, with a mean of 4.07+/- 2.60 microgC m-3, while the hourly average EC concentration ranged approximately from 0.04 to 8.19 .microgC m-3, with a mean of 1.35 +/- 0.71 microgC m-3, from May 28 to June 17, 2009. During the fall season, OC varied in the approximate range 0.9-9.6 microgC m-3, with a mean of 2.30 +/-0.80 microgC m-3, whereas EC ranged approximately from 0.01 to 5.40 microgC m-3, with a mean of 0.66 +/- 0.38 microgC m-3. Average contributions of EC to TC and WSOC to OC were 26.0% +/- 9.7% and 20.6% +/-7.4%, and 37.6% +/- 23.5% and 57.2% +/- 22.2% during summer and fall seasons, respectively. As expected, clear diurnal variation of WSOC/OC was found in summer, varying from 0.22 during the nighttime up to 0.72 during the daytime, mainly due to the photo-oxidation process. In order to investigate the effect of air mass pathway on the characteristics of carbonaceous aerosol, 5-day back-trajectory analysis was conducted using the HYSPLIT model. The air mass pathways were classified into four types: Continental (CC), Marine (M), East Sea (ES) and Korean Peninsula (KP). The highest OC/EC ratio of 3.63 was observed when air mass originated from the Continental area (CC). The lowest OC/EC ratio of 0.79 was measured when air mass originated from the Marine area (M). A high OC concentration was occasionally observed at Gosan due to local biomass burning activities. The contribution of secondary OC to total OC varied approximately between 8.4% and 32.2% and depended on air mass type.
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Affiliation(s)
- T Batmunkh
- Advanced Environmental Monitoring Research Center (ADEMRC), School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
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Lee K, Kim JH, Lee JH, Lee WY, Park MS, Kim JY, Kim KC, Lee MG, Jung KS, Kim YS, Shin YM, Koh Y. Acute respiratory distress syndrome caused by miliary tuberculosis: a multicentre survey in South Korea. Int J Tuberc Lung Dis 2011; 15:1099-103. [PMID: 21740675 DOI: 10.5588/ijtld.10.0557] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Miliary tuberculosis (TB) is an unusual cause of acute respiratory distress syndrome (ARDS). OBJECTIVE To evaluate the clinical characteristics and outcomes of patients with ARDS caused by miliary TB admitted to the intensive care unit (ICU). DESIGN A total of 67 patients were enrolled during the period 1999-2008. RESULTS The median age of the patients was 56 years (range 17-81), 19 (28.4%) were aged >71 years, and 38 (56.7%) were male. All-cause mortality in the ICU and hospital were respectively 58.2% and 61.2%. Of the total number of enrolled patients, 49 (73.1%) were prescribed anti-tuberculosis medication within 3 days of hospital admission. On the day of ARDS diagnosis (10.0 ± 3.7 vs. 7.4 ± 3.5, P = 0.005), non-survivors had a significantly higher Sequential Organ Failure Assessment (SOFA) score than survivors. Multivariate analysis showed that SOFA score on the day of ARDS diagnosis was a significant predictor of survival (OR 0.809, 95%CI 0.691-0.946, P = 0.008). It was difficult to determine the efficacy of systemic corticosteroids on patient survival. CONCLUSION ARDS caused by miliary TB was associated with a high in-hospital mortality rate, with SOFA score on the day of ARDS diagnosis being a valuable prognostic indicator.
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Affiliation(s)
- K Lee
- Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
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Kim KC, Lee SJ. The 14th International Symposium on Flow Visualization, ISFV14. J Vis (Tokyo) 2011. [DOI: 10.1007/s12650-011-0099-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ji HS, Kang M, Kim KC. Abstract: 133 HEMODYNAMIC AND HEMORHEOLOGICAL FEATURE INVESTIGATION IN RIGHT CORONARY ARTERY STENOSIS WITH 83% SEVERITY. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70247-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Singh K, Kim KC. Multi-prong approaches to monitor the biomechanical aspects of abnormal bones. IJBET 2009. [DOI: 10.1504/ijbet.2009.024426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Singh K, Rahman MA, Son JI, Kim KC, Shim YB. An amperometric immunosensor for osteoproteogerin based on gold nanoparticles deposited conducting polymer. Biosens Bioelectron 2008; 23:1595-601. [PMID: 18304799 DOI: 10.1016/j.bios.2008.01.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 12/13/2007] [Accepted: 01/16/2008] [Indexed: 11/17/2022]
Abstract
An amperometric immunosensor was fabricated for the detection of osteoproteogerin (OPG) by covalently immobilizing a monoclonal OPG antibody (anti-OPG) onto the gold nanoparticles (AuNPs) deposited functionalized conducting polymer (5,2':5',2''-terthiophene-3'-carboxylic acid). AuNPs were electrochemically deposited onto the conducting polymer using cyclic voltammetry. The particle size of deposited AuNPs was controlled by varying the scan rate and was characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The immobilization of anti-OPG was also confirmed using XPS. The principle of immunosensor was based on a competitive immunoassay between free-OPG and labeled-OPG for the active sites of anti-OPG. HRP was used as a label that electrochemically catalyzes the H(2)O(2) reduction. The catalytic reduction was monitored amperometrically at -0.4V vs. Ag/AgCl. The immunosensor showed a linear range between 2.5 and 25pg/ml and the detection limit was determined to be 2pg/ml. The proposed immunosensor was successfully applied for real human samples to detect OPG.
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Affiliation(s)
- Kanika Singh
- School of Mechanical Engineering and MEMS/Nano Technology Center, Pusan National University, Pusan 609-735, South Korea
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Singh K, Kim KC. Investigating new BioMEMS techniques for early detection of osteoporosis. Annu Int Conf IEEE Eng Med Biol Soc 2007; 2007:2265-8. [PMID: 18002442 DOI: 10.1109/iembs.2007.4352776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Osteoporosis is a bone disease which requires early detection. The biomarkers provide a promising challenge of clinical proteomics for early disease detection. Different techniques like BMD testing, optical and electrochemical testing have been studied comparatively. New peaks have been identified in UV-visible spectroscopy at 420nm and high sensitivity is achieved by electrochemical technique with ng/ml to pico/ml level detection of bonemarkers. An electrochemical technique is found to be the best suitable for developing a new bioMEMS chip.
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Affiliation(s)
- Kanika Singh
- MEMS/Nano Technology Center, Pusan National University, Busan, South Korea.
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Rhee KJ, Kim KC, Lee JK, Hwang DS, Shin HD, Yang JY, Kim YM. Incomplete discoid glenoid labrum combined with a ganglion cyst of the spinoglenoid notch. ACTA ACUST UNITED AC 2006; 88:1390-2. [PMID: 17012434 DOI: 10.1302/0301-620x.88b10.18027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In a 41-year-old man, right-sided infraspinatus muscle weakness was associated with compression of the suprascapular nerve caused by a spinoglenoid ganglion cyst. The lesion was confirmed using electromyography and MRI. In addition, arthroscopy showed an incomplete discoid labrum. The free inner edge of the labrum was removed as in a meniscectomy of a discoid meniscus in the knee joint. Arthroscopic decompression of the cyst was performed through a juxtaglenoid capsulotomy which was left open. Neurological function recovered completely.
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Affiliation(s)
- K J Rhee
- Department of Orthopaedic Surgery, Chungnam National University College of Medicine, Jung-Gu, Daejeon 301-040, Republic of Korea
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Woo SH, Yu SO, Kim KC, Silao JI, Lee GJ, Kim JS. Salvage of the lower extremity free flap using cross-leg venous repair. J Plast Reconstr Aesthet Surg 2006; 59:928-34. [PMID: 16920584 DOI: 10.1016/j.bjps.2006.01.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Revised: 12/16/2005] [Accepted: 01/01/2006] [Indexed: 11/19/2022]
Abstract
This retrospective study was designed to evaluate a salvage technique for free flaps suffering venous congestion by using a cross-leg vein repair in patients with venous-impaired lower extremities. Four free flap reconstructions were performed using the latissimus dorsi muscle to reconstruct soft tissue defects in the lower extremity. The recipient artery was confined to the ipsilateral leg and the venous anastomosis was performed with a long saphenous vein from the contralateral side. The legs were immobilised together by means of an external fixator. All patients were males with a mean age of 31 years. The mean time of pedicle division was 8.8 days (7-10). The mean size of the free flap was 186.5 cm(2). All flaps survived after pedicle division without venous congestion. There were no complications such as joint stiffness or donor site morbidity except for a linear scar. The cross-leg venous repair is a refinement of a salvage procedure for compromised free flaps used in the reconstruction of severe soft tissue defects in vascularly compromised lower extremities.
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Affiliation(s)
- S H Woo
- Kim & Woo's Institute for Hand & Reconstructive Microsurgery, Daegu, Korea.
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Croce MV, Isla-Larrain M, Remes-Lenicov F, Colussi AG, Lacunza E, Kim KC, Gendler SJ, Segal-Eiras A. MUC1 cytoplasmic tail detection using CT33 polyclonal and CT2 monoclonal antibodies in breast and colorectal tissue. Histol Histopathol 2006; 21:849-55. [PMID: 16691537 DOI: 10.14670/hh-21.849] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
UNLABELLED The immunohistochemical detection (IHC) of MUC1-CT employing a polyclonal antibody (CT33) in relation to CT2 monoclonal antibody (MAb) was analyzed. Western blot (WB) was used to determine the molecular mass of CT. MATERIALS AND METHODS We studied 163 breast and 89 colorectal cancer specimens, 10 breast and 14 colorectal benign conditions, and 12 breast and 20 colorectal normal samples. From each tumor sample, subcellular fractions were obtained and analyzed by SDS-PAGE and WB. A nonparametric statistical analysis was employed; data were standardized and a Kendall-Tau correlation was applied. RESULTS By IHC, 146/163 (90%) and 151/163 (93%) of breast cancer were positive with CT33 and CT2, respectively; a statistically significant correlation was obtained (t=0.5199). Seven out of ten (70%) benign breast specimens were positive with CT33 while all samples stained with CT2; in normal breast sample tissues, all were positive with both Abs. In colorectal cancer samples, both antibodies stained 47/89 (53%) samples; CT2 reacted in 13/14 (93%) of benign samples while CT33 showed a positive reaction in 9/14 (64%) of benign specimens. In normal samples, CT2 showed staining in 17/20 (85%) of samples and CT33 was reactive in 12/20 (60%). By WB, in breast and colorectal cancer samples, similar results were obtained with both antibodies: a main band at about 30kDa which represents the smaller subunit. CONCLUSION CT33 polyclonal antibody has demonstrated its efficacy to detect MUC1 in breast and colorectal cancer tissues with similar reactivity to CT2. It is worthwhile to affirm that CT33 is a good indicator of MUC1 expression.
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Affiliation(s)
- M V Croce
- Centre of Basic and Applied Immunological Research (CINIBA), Faculty of Medical Sciences, UNLP, La Plata, Argentina
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Abraham S, Jeong EH, Arakawa T, Shoji S, Kim KC, Kim I, Go JS. Microfluidics assisted synthesis of well-defined spherical polymeric microcapsules and their utilization as potential encapsulants. Lab Chip 2006; 6:752-6. [PMID: 16738726 DOI: 10.1039/b518006f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In this article, the development of a novel technique to fabricate spherical polymeric microcapsules by utilizing microfluidic technology is presented. Atom transfer radical polymerization (ATRP) was employed to synthesize well-defined amphiphilic block copolymers. An organic polymer solution was constrained to adopt the spherical droplets in a continuous water phase at a T-junction microchannel, and the generation of the droplets was studied quantitatively. The flow conditions of two immiscible solutions were adjusted for the successful generation of the polymer droplets. The morphology of the microcapsules was examined. The efficiency of these polymer microcapsules as containers for the storage and controlled release of loaded molecules was evaluated by encapsulating the microcapsules with Congo-red dye and investigating the release performance using temperature controlled UV-VIS spectroscopy.
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Affiliation(s)
- Sinoj Abraham
- Department of Polymer Science and Engineering, Pusan National University, Busan 609-735, S. Korea.
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Techakittiroj C, Kim KC, Andersson H, Li MM. 9p subtelomere deletion: pathogenic mutation or normal variant? Beijing Da Xue Xue Bao Yi Xue Ban 2006; 38:92-3. [PMID: 16415976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We report an apparently benign familial 9p subtelomere deletion identified using chromosome-arm-specific subtelomere probes in a patient with multiple congenital anomalies. Our experience demonstrated that the discovery of a subtelomeric deletion and/or duplication does not always guarantee the identification of the etiology for the patients phenotype and a positive finding with subtelomere probes should always be followed by parental study with the same probe in order to distinguish a disease causing alteration from a benign familial polymorphism.
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Bhat SS, Schmidt KR, Ladd S, Kim KC, Schwartz CE, Simensen RJ, DuPont BR, Stevenson RE, Srivastava AK. Disruption of DMD and deletion of ACSL4 causing developmental delay, hypotonia, and multiple congenital anomalies. Cytogenet Genome Res 2006; 112:170-5. [PMID: 16276108 DOI: 10.1159/000087531] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 03/07/2005] [Indexed: 01/06/2023] Open
Abstract
We have studied a male patient with significant developmental delay, growth failure, hypotonia, girdle weakness, microcephaly, and multiple congenital anomalies including atrial (ASD) and ventricular (VSD) septal defects. Detailed cytogenetic and molecular analyses revealed three de novo X chromosome aberrations and a karyotype 46,Y,der(X)inv(X) (p11.4q11.2)inv(X)(q11.2q21.32 approximately q22.2)del(X)(q22.3q22.3) was determined. The three X chromosome aberrations in the patient include: a pericentric inversion (inv 1) that disrupted the Duchenne muscular dystrophy (DMD) gene, dystrophin, at Xp11.4; an Xq11.2q21.32 approximately q22.2 paracentric inversion (inv 2) putatively affecting no genes; and an interstitial deletion at Xq22.3 that results in functional nullisomy of several known genes, including a gene previously associated with X-linked nonsyndromic mental retardation, acyl-CoA synthetase long chain family member 4 (ACSL4). These findings suggest that the disruption of DMD and the absence of ACSL4 in the patient are responsible for neuromuscular disease and cognitive impairment.
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Affiliation(s)
- S S Bhat
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, SC, USA
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Kim KC, Lee BC, Pou S, Ciccolella D. Effects of activation of polymorphonuclear leukocytes on airway goblet cell mucin release in a co-culture system. Inflamm Res 2003; 52:258-62. [PMID: 12835897 DOI: 10.1007/s00011-003-1171-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE AND DESIGN Effects of activated PMN on airway goblet cell mucin release were investigated using a co-culture system in which both tracheal surface epithelial (TSE) cells and PMN from hamsters were present. MATERIALS AND METHODS TSE cells were metabolically labeled using (3)H-glucosamine and chased in the presence of PMN under various experimental designs. PMN were obtained from the bronchoalveolar lavage fluid of hamsters following intratracheal instillation of E. coli endotoxin. The amount of (3)H-mucin was measured by Sepharose CL-4B gel-filtration column chromatography. RESULTS (i). activation of 10(6) PMN by fMLP (0.1 microM) and cytochalasin B (0.1 microM) resulted in production of both the estrolytic ("elastolytic") activity and superoxide, (ii). activation of PMN in the co-culture stimulated mucin release from TSE cells followed by a significant degradation of the released mucins, both of which were blocked in a dose-dependent fashion by pretreatment with alpha1-protease inhibitor, and (iii). generation of varying concentrations of superoxide in the TSE cell culture did not affect mucin release from TSE cells. CONCLUSION In the co-culture system, activation of PMN results in release and degradation of mucins, both of which are almost entirely accounted for by serine proteases but not other cellular products such as superoxide.
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Affiliation(s)
- K C Kim
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 N Pine St, Baltimore, MD 21201, USA.
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Jiang G, Yang F, Li M, Weissbecker K, Price S, Kim KC, La Russa VF, Safah H, Ehrlich M. Imatinib (ST1571) provides only limited selectivity for CML cells and treatment might be complicated by silent BCR-ABL genes. Cancer Biol Ther 2003; 2:103-8. [PMID: 12673129 DOI: 10.4161/cbt.240] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Very promising results have been obtained in clinical trials on chronic-phase chronic myeloid leukemia (CP-CML) patients treated with imatinib mesylate (IM; Gleevecr, STI571), a BCR-ABL tyrosine kinase inhibitor. However, we found that IM caused considerable inhibition of normal hematopoietic progenitor cells upon treating control bone marrow (BM) cultures. In vitro IM treatment gave a decrease in the yield and size of colonies from BM of untreated CP-CML patients that was only two to three times that from the normal samples. Moreover, about 30% of myeloid progenitors (CFU-GM) from CML BM still formed colonies in the presence of IM, most of which had BCR-ABL RNA. About half of these treated colonies also displayed methylation of the internal ABL Pa promoter, a CML-specific epigenetic alteration, which was used in this study as a marker for BCR-ABL translocation-containing cells. However, ~5-8% of the treated or the untreated CML BM-derived colonies had no detectable BCR-ABL RNA by two or three rounds of RT-PCR despite being positive for the internal standard RNA and displaying hallmarks of CML, either t(9;22)(q34;ql 1) or ABL Pa methylation. Our results indicate that IM is only partially specific for CML progenitor cells compared to normal hematopoietic progenitor cells and suggest that some CML cells may have a silent BCR-ABL oncogene that could interfere with therapy.
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MESH Headings
- Benzamides
- Bone Marrow Cells/drug effects
- Bone Marrow Cells/pathology
- Bone Marrow Cells/physiology
- Chromosome Aberrations
- Chromosomes, Human, Pair 22/genetics
- Chromosomes, Human, Pair 9/genetics
- Colony-Forming Units Assay
- DNA Methylation/drug effects
- Fusion Proteins, bcr-abl/genetics
- Fusion Proteins, bcr-abl/metabolism
- Hematopoietic Stem Cells/drug effects
- Hematopoietic Stem Cells/pathology
- Hematopoietic Stem Cells/physiology
- Humans
- Imatinib Mesylate
- In Situ Hybridization, Fluorescence
- Karyotyping
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Neoplastic Stem Cells/drug effects
- Neoplastic Stem Cells/pathology
- Neoplastic Stem Cells/physiology
- Piperazines
- Promoter Regions, Genetic
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription, Genetic
- Translocation, Genetic
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Affiliation(s)
- Guanchao Jiang
- Tulane Cancer Center and Humon Genetics Program, Tulane Medical School, New Orleans, Lousiana 70112, USA
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Kim KC, Hurh WM, Fernandez M. Intra-group differences in business participation: three Asian immigrant groups. Int Migr Rev 2002; 23:73-95. [PMID: 12342478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
This study investigates ethnic and nativity differentials in self-employment based on the small-business experiences of 3 Asian immigrant groups in the US: Korean, Chinese, and Asian Indians. In light of the 1980 Census data, the intra- and the inter-group differences in the business participation rates of these Asian immigrant groups are examined. Findings reveal that each group has substantial intra-group differences in the business participation rate, and the differences can best be explained by the interactive approach proposed by this study. Moreover, a comparative study (inter-group comparison) of these intra-group differences opens a new avenue to understanding the various patterns of business participation among recent immigrants from Asia.
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Lee CJ, Paik SH, Ko KH, Kim KC. Effects of polycationic peptides on mucin release from airway goblet cells: relationship between polymer size and activity. Inflamm Res 2002; 51:490-4. [PMID: 12477077 DOI: 10.1007/pl00012417] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES AND DESIGN Various sizes of poly-L-lysine (PLL) and poly-L-arginine (PLA) were tested for their possible effects on airway goblet cell mucin release using primary hamster tracheal surface epithelial (HTSE) cells in an attempt to identify the smallest size of the polycationic peptide to suppress mucin release without cytotoxicity. MATERIALS AND METHODS HTSE cells were metabolically labeled using 3H-glucosamine and chased in the presence of varying concentrations of various sizes of the polycationic peptides. The amount of 3H-mucin in the spent media was measured by Sepharose CL-4B gel-filtration column chromatography. Possible cytotoxicity of the peptides was assessed by measuring the release of lactic dehydrogenase (LDH) during the treatment period. RESULTS (1) PLL (MW 78,000) inhibited whereas PLA (MW 92,000) stimulated mucin release. However, these peptides were cytotoxic at the effective concentrations; (2) Both PLL (MW 9,600) and PLA (MW 8,900) could inhibit mucin release in a dose dependent manner without cytotoxicity; (3) Both PLL and PLA were effective in suppressing mucin release in 20-mer but not in either 10-mer or 5-mer; (4) 14-mers of both PLL and PLA also inhibited mucin release without cytotoxicity; (5) PLL and poly-D-lysine (PDL) of 14-mer were equipotent in its ability to suppress mucin release. CONCLUSION Both PLL and PLA are cytotoxic at 'high' molecular weights, but have an ability to suppress mucin release without cytotoxicity at 'low' molecular weights. 14-mer seems to be the small, effective size, if not the smallest, for both PLL and PLA to suppress mucin release without cytotoxicity. The inhibitory effect of these polycationic peptides seems to be determined by the presence and the absolute number of positive charges and also to be independent of optical isomerism.
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Affiliation(s)
- C J Lee
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD 21201, USA
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Kim KC. [Ichthyosis]. Ryoikibetsu Shokogun Shirizu 2002:5-6. [PMID: 11528861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Affiliation(s)
- K C Kim
- Department of Pediatrics, Dokkyo University School of Medicine, Koshigaya Hospital
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Kim KC. [Immunodeficiency, hyper IgE type]. Ryoikibetsu Shokogun Shirizu 2002:10-1. [PMID: 11528639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Affiliation(s)
- K C Kim
- Department of Pediatrics, Dokkyo University School of Medicine, Koshigaya Hospital
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