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Lee MJ, Lee HN, Lee GE, Han ST, Kang DW, Yang JR. CMOS Detector Staggered Array Module for Sub-Terahertz Imaging on Conveyor Belt System. Sensors (Basel) 2023; 23:s23031232. [PMID: 36772271 PMCID: PMC9920622 DOI: 10.3390/s23031232] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/17/2023] [Accepted: 01/17/2023] [Indexed: 05/27/2023]
Abstract
A complementary metal-oxide-semiconductor (CMOS) detector array is proposed to improve the sub-terahertz imaging resolution for objects in the conveyor belt system. The image resolution is limited to the implemented configuration, such as the wide spacing in the detector array, the high conveyor belt speed, and the slow response of the signal conditioning block. The proposed array can improve the image resolution in the direction perpendicular to the movement of the belt, which is determined by the size and interval of the detector pixel, by configuring the array into two replaceable columns located at the misaligned horizontal positions. Replaceable detector unit pixels are individually attached to the motherboard after measuring and evaluating the detection performance to construct the proposed array. The intensities of 32 detector pixels placed under the conveyor belt with a width of 160 mm were initially calibrated in every image, including the beam pattern of 0.2 THz signals generated from the gyrotron. The image resolution of the perpendicular direction obtained from the proposed array was measured to be approximately 5 mm at a conveyor belt speed of 16 mm/s, demonstrating a 200% improvement in resolution compared to the conventional linear array under the same conditions.
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Affiliation(s)
- Moon-Jeong Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Ha-Neul Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Ga-Eun Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Seong-Tae Han
- Electrophysics Research Center, Korea Electrotechnology Research Institute, Changwon 51543, Republic of Korea
| | - Dong-Woo Kang
- AI Compact SoC Research Section, Electronics and Telecommunications Research Institute, Daejeon 34129, Republic of Korea
| | - Jong-Ryul Yang
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
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Lee MJ, Lee HN, Lee GE, Han ST, Yang JR. Concurrent-Mode CMOS Detector IC for Sub-Terahertz Imaging System. Sensors (Basel) 2022; 22:s22051753. [PMID: 35270903 PMCID: PMC8914706 DOI: 10.3390/s22051753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/15/2022] [Accepted: 02/22/2022] [Indexed: 02/01/2023]
Abstract
A CMOS detector with a concurrent mode for high-quality images in the sub-terahertz region has been proposed. The detector improves output-signal coupling characteristics at the output node. A cross-coupling capacitor is added to isolate the DC bias between the drain and gate. The detector is designed to combine a 180° phase shift based on common source operation and an in-phase output signal based on the drain input. The circuit layout and phase shift occurring in the cross-coupled capacitor during phase coupling are verified using an EM simulation. The detector is fabricated using the TSMC 0.25-μm mixed-signal 1-poly 5-metal layer CMOS process, where the size, including the pad, is 1.13 mm × 0.74 mm. The detector IC comprises a folded dipole antenna, the proposed detector, a preamplifier, and a voltage buffer. Measurement results using a 200-GHz gyrotron source demonstrate that the proposed detector voltage responsivity is 14.13 MV/W with a noise-equivalent power of 34.42 pW/√Hz. The high detection performance helps resolve the 2-mm line width. The proposed detector exhibits a signal-to-noise ratio of 49 dB with regard to the THz imaging performance, which is 9 dB higher than that of the previous CMOS detector core circuits with gate-drain capacitors.
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Affiliation(s)
- Moon-Jeong Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Korea; (M.-J.L.); (H.-N.L.); (G.-E.L.)
| | - Ha-Neul Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Korea; (M.-J.L.); (H.-N.L.); (G.-E.L.)
| | - Ga-Eun Lee
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Korea; (M.-J.L.); (H.-N.L.); (G.-E.L.)
| | - Seong-Tae Han
- Electrophysics Research Center, Korea Electrotechnology Research Institute, Changwon 51543, Korea;
| | - Jong-Ryul Yang
- Department of Electronic Engineering, Yeungnam University, Gyeongsan 38541, Korea; (M.-J.L.); (H.-N.L.); (G.-E.L.)
- Correspondence: ; Tel.: +82-53-810-2495
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Cho C, Han ST, Jin YS. Design and test of high-voltage, high-repetition rotary trigger double spark gap switch. Rev Sci Instrum 2021; 92:014702. [PMID: 33514232 DOI: 10.1063/5.0023652] [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: 08/10/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Spark gap switches are used in various high-power pulse systems because they can quickly transfer the energy stored in the capacitor to the load. A rotary trigger double spark gap (RTDSG) switch is proposed in this paper as a type of switch capable of high repetition at high power. It was found that a pulse switching of 20 kV and 1 kHz was possible by applying the multiple RTDSG switches to increase the repetition rate of the switch. In addition to the basic operating principle of the RTDSG, the effects of switching-related parameters on the operating frequency of the switch were analyzed. As an example of promising applications of the high repetition RTDSG, the generation of shock waves by underwater discharge and the effective dispersion of carbon nanotubes using the shock waves are reported.
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Affiliation(s)
- Chuhyun Cho
- Korea Electrotechnology Research Institute, 12 Bulmosan-ro 10beon-gil, Seongsan-gu, Changwon-si Gyeongsangnamdo, 51543, South Korea
| | - Seong-Tae Han
- Korea Electrotechnology Research Institute, 12 Bulmosan-ro 10beon-gil, Seongsan-gu, Changwon-si Gyeongsangnamdo, 51543, South Korea
| | - Yun-Sik Jin
- Korea Electrotechnology Research Institute, 12 Bulmosan-ro 10beon-gil, Seongsan-gu, Changwon-si Gyeongsangnamdo, 51543, South Korea
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Yang JR, Han ST, Baek D. Differential CMOS Sub-Terahertz Detector with Subthreshold Amplifier. Sensors (Basel) 2017; 17:s17092069. [PMID: 28891927 PMCID: PMC5620660 DOI: 10.3390/s17092069] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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: 07/17/2017] [Revised: 09/04/2017] [Accepted: 09/06/2017] [Indexed: 12/03/2022]
Abstract
We propose a differential-type complementary metal-oxide-semiconductor (CMOS) sub-terahertz (THz) detector with a subthreshold preamplifier. The proposed detector improves the voltage responsivity and effective signal-to-noise ratio (SNR) using the subthreshold preamplifier, which is located between the differential detector device and main amplifier. The overall noise of the detector for the THz imaging system is reduced by the preamplifier because it diminishes the noise contribution of the main amplifier. The subthreshold preamplifier is self-biased by the output DC voltage of the detector core and has a dummy structure that cancels the DC offsets generated by the preamplifier itself. The 200 GHz detector fabricated using 0.25 μm CMOS technology includes a low drop-out regulator, current reference blocks, and an integrated antenna. A voltage responsivity of 2020 kV/W and noise equivalent power of 76 pW/√Hz are achieved using the detector at a gate bias of 0.5 V, respectively. The effective SNR at a 103 Hz chopping frequency is 70.9 dB with a 0.7 W/m2 input signal power density. The dynamic range of the raster-scanned THz image is 44.59 dB.
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Affiliation(s)
- Jong-Ryul Yang
- Department of Electronic Engineering, Yeungnam University, Gyeongsan, Gyeongbuk-do 38541, Korea.
| | - Seong-Tae Han
- Electric Propulsion Research Center, Korea Electrotechnology Research Institute, Changwon, Gyeongnam-do 51543, Korea.
| | - Donghyun Baek
- School of Electrical Engineering, Chung-Ang University, Seoul 06974, Korea.
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Han SP, Ko H, Kim N, Lee WH, Moon K, Lee IM, Lee ES, Lee DH, Lee W, Han ST, Choi SW, Park KH. Real-time continuous-wave terahertz line scanner based on a compact 1 × 240 InGaAs Schottky barrier diode array detector. Opt Express 2014; 22:28977-28983. [PMID: 25402136 DOI: 10.1364/oe.22.028977] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate real-time continuous-wave terahertz (THz) line-scanned imaging based on a 1 × 240 InGaAs Schottky barrier diode (SBD) array detector with a scan velocity of 25 cm/s, a scan line length of 12 cm, and a pixel size of 0.5 × 0.5 mm². Foreign substances, such as a paper clip with a spatial resolution of approximately 1 mm that is hidden under a cracker, are clearly detected by this THz line-scanning system. The system consists of the SBD array detector, a 200-GHz gyrotron source, a conveyor system, and several optical components such as a high-density polyethylene cylindrical lens, metal cylindrical mirror, and THz wire-grid polarizer. Using the THz polarizer, the signal-to-noise ratio of the SBD array detector improves because the quality of the source beam is enhanced.
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Park SJ, Hong JT, Choi SJ, Kim HS, Park WK, Han ST, Park JY, Lee S, Kim DS, Ahn YH. Detection of microorganisms using terahertz metamaterials. Sci Rep 2014; 4:4988. [PMID: 24832607 PMCID: PMC4023130 DOI: 10.1038/srep04988] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [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: 11/26/2013] [Accepted: 04/28/2014] [Indexed: 12/23/2022] Open
Abstract
Microorganisms such as fungi and bacteria cause many human diseases and therefore rapid and accurate identification of these substances is essential for effective treatment and prevention of further infections. In particular, contemporary microbial detection technique is limited by the low detection speed which usually extends over a couple of days. Here we demonstrate that metamaterials operating in the terahertz frequency range shows promising potential for use in fabricating the highly sensitive and selective microbial sensors that are capable of high-speed on-site detection of microorganisms in both ambient and aqueous environments. We were able to detect extremely small amounts of the microorganisms, because their sizes are on the same scale as the micro-gaps of the terahertz metamaterials. The resonant frequency shift of the metamaterials was investigated in terms of the number density and the dielectric constants of the microorganisms, which was successfully interpreted by the change in the effective dielectric constant of a gap area.
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Affiliation(s)
- S J Park
- Department of Physics and Division of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - J T Hong
- Department of Physics and Division of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - S J Choi
- Department of Biological Science, Ajou University, Suwon 443-749, Korea
| | - H S Kim
- Department of Biological Science, Ajou University, Suwon 443-749, Korea
| | - W K Park
- Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan 426-170, Korea
| | - S T Han
- Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan 426-170, Korea
| | - J Y Park
- Department of Physics and Division of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - S Lee
- Department of Physics and Division of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - D S Kim
- Center for Subwavelength Optics and Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea
| | - Y H Ahn
- Department of Physics and Division of Energy Systems Research, Ajou University, Suwon 443-749, Korea
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Mya DHT, Han ST, Linn YC, Hwang WYK, Goh YT, Tan DCL. Risk of hepatitis B reactivation and the role of novel agents and stem-cell transplantation in multiple myeloma patients with hepatitis B virus (HBV) infection. Ann Oncol 2011; 23:421-6. [PMID: 21551005 DOI: 10.1093/annonc/mdr142] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The purpose of the study is to analyse the prevalence of hepatitis B virus (HBV) infection and its incidence of reactivation among multiple myeloma (MM) patients treated in the era of novel therapy in an endemic Asian setting. PATIENTS AND METHODS From 2000 to 2008, 273 patients with newly diagnosed MM were screened for the presence of hepatitis B virus surface antigen and HBV core antibody. HBV-infected patients were prospectively followed for reactivation with serial monitoring of serum alanine transferase and HBV DNA load. The patterns of HBV reactivation in relation to treatment received, exposure to high-dose therapy with autologous stem-cell transplantation (HDT/ASCT) and novel agents were studied. RESULTS The prevalence of HBV infection was 5.5%. Three cases of HBV reactivation despite lamivudine prophylaxis were reported. Two patients reactivated 3-5 months after HDT/ASCT while receiving thalidomide maintenance and one reactivated 3 years after HDT/ASCT and shortly after bortezomib salvage therapy. Emergence of a mutant HBV strain was documented in one patient. CONCLUSIONS Use of prophylaxis may reduce but will not preclude HBV reactivation. Highest risk occurs during immune reconstitution phase of HDT/ASCT. The role of immunomodulatory agents in HBV reactivation needs to be further elucidated. Separate HBV prophylaxis and surveillance guidelines ought to be developed for patients with MM.
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Affiliation(s)
- D H T Mya
- Department of Haematology, Singapore General Hospital, Singapore, Republic of Singapore
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Yang JW, Han ST, Kim YS, Song SH, Kim BR, Eom MS, Jung SH, Choi SO, Han BG. Effects of a cGMP-specific phosphodiesterase inhibitor on expression of endothelial nitric oxide synthase and vascular endothelial growth factor in rats with cyclosporine-induced nephrotoxicity. Transplant Proc 2011; 42:4625-32. [PMID: 21168749 DOI: 10.1016/j.transproceed.2010.09.167] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [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: 05/08/2010] [Revised: 09/08/2010] [Accepted: 09/30/2010] [Indexed: 11/18/2022]
Abstract
BACKGROUND The mechanism of cyclosporine (CsA)-induced nephrotoxicity has been suggested to be vasoconstriction due to reduced nitric oxide (NO), providing tissue fibrosis by elevation of transforming growth factor beta and vascular endothelial growth factor (VEGF). In this study using a rat model of CsA-induced nephrotoxicity, we administered a phosphodiesterase-5 inhibitor to ameliorate the renal injury and alter the expression of endothelial No synthase (eNOS) and VEGF. METHODS A right nephrectomy was performed in Sprague-Dawley rats (n = 30; 200-250 g, all male). The Ischemia group (n = 6) underwent ligation of the left renal artery for 45 minutes (IR) before observation for 28 days. After IR, the udenafil group (n = 6) was treated with 10 mg/kg drug orally, the CsA group (n = 6) received 15 mg/kg CsA injected subcutaneously and the CsA plus udenafil group (n = 6) received 15 mg/kg CsA injected subcutaneously together with the oral administration of 10 mg/kg udenafil. RESULTS Administration of udenafil significantly decreased serum creatinine either alone (0.21 ± 0.04 mg/dL) or in combination with CsA (1.86 ± 0.35 mg/dL) versus the ischemia (0.85 ± 0.22 mg/dL) and the CsA alone (3. 10 ± 0.77 mg/dL) group. (P = .002; P = .002). Comparing the Hematoxylin-eosin staining of the ischemia (0.41 ± 0.09) and CsA (0.44 ± 0.08) groups showed a significantly decreased loss of nuclei in proximal tubules after the administration of udenafil (0.27 ± 0.05 [P = .004] and 0.26 ± 0.02 [P = .002] respectively). Immunohistochemical staining showed strong eNOS staining in the udenafil and CsA plus udenafil groups. Western blots for eNOS showed decreased expression in the CsA group and increased expression in the udenafil group. Western blots for VEGF revealed reduced expression only in the CsA plus udenafil group. eNOS mRNA was decreased in the CsA (0.017 ± 0.010) compared with the ischemia group (0.048 ± 0.015; P = .000). VEGF mRNA which was decreased in the CsA group (2.026 ± 1.109), showed greater tendency after administration of udenafil (0.440 ± 0.449) (P = .003). CONCLUSION The phosphodiesterase inhibitor ameliorated renal injury in a rat model of CsA-induced nephrotoxicity, possibly related to increased eNOS and reduced VEGF expression.
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Affiliation(s)
- J W Yang
- Department of Nephrology, Yonsei University Wonju College of Medicine, Wonju, Gangwon, Korea
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Torrezan AC, Han ST, Mastovsky I, Shapiro MA, Sirigiri JR, Temkin RJ, Griffin RG, Barnes AB. Continuous-Wave Operation of a Frequency-Tunable 460-GHz Second-Harmonic Gyrotron for Enhanced Nuclear Magnetic Resonance. IEEE Trans Electron Devices 2010; 38:1150-1159. [PMID: 23761938 PMCID: PMC3677787] [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] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The design, operation, and characterization of a continuous-wave (CW) tunable second-harmonic 460-GHz gyrotron are reported. The gyrotron is intended to be used as a submillimeter-wave source for 700-MHz nuclear magnetic resonance experiments with sensitivity enhanced by dynamic nuclear polarization. The gyrotron operates in the whispering-gallery mode TE11,2 and has generated 16 W of output power with a 13-kV 100-mA electron beam. The start oscillation current measured over a range of magnetic field values is in good agreement with theoretical start currents obtained from linear theory for successive high-order axial modes TE11,2,q. The minimum start current is 27 mA. Power and frequency tuning measurements as a function of the electron cyclotron frequency have also been carried out. A smooth frequency tuning range of 1 GHz was obtained for the operating second-harmonic mode either by magnetic field tuning or beam voltage tuning. Long-term CW operation was evaluated during an uninterrupted period of 48 h, where the gyrotron output power and frequency were kept stable to within ±0.7% and ±6 ppm, respectively, by a computerized control system. Proper operation of an internal quasi-optical mode converter implemented to transform the operating whispering-gallery mode to a Gaussian-like beam was also verified. Based on the images of the gyrotron output beam taken with a pyroelectric camera, the Gaussian-like mode content of the output beam was computed to be 92% with an ellipticity of 12%.
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Affiliation(s)
- Antonio C Torrezan
- Department of Electrical Engineering and Computer Science and the Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA ( )
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Torrezan AC, Han ST, Mastovsky I, Shapiro MA, Sirigiri JR, Temkin RJ, Barnes AB, Griffin RG. Continuous-Wave Operation of a Frequency-Tunable 460-GHz Second-Harmonic Gyrotron for Enhanced Nuclear Magnetic Resonance. IEEE Trans Plasma Sci IEEE Nucl Plasma Sci Soc 2010; 38:1150-1160. [PMID: 21243088 PMCID: PMC3021140 DOI: 10.1109/tps.2010.2046617] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The design, operation, and characterization of a continuous-wave (CW) tunable second-harmonic 460-GHz gyrotron are reported. The gyrotron is intended to be used as a submillimeter-wave source for 700-MHz nuclear magnetic resonance experiments with sensitivity enhanced by dynamic nuclear polarization. The gyrotron operates in the whispering-gallery mode TE(11,2) and has generated 16 W of output power with a 13-kV 100-mA electron beam. The start oscillation current measured over a range of magnetic field values is in good agreement with theoretical start currents obtained from linear theory for successive high-order axial modes TE(11,2,q). The minimum start current is 27 mA. Power and frequency tuning measurements as a function of the electron cyclotron frequency have also been carried out. A smooth frequency tuning range of 1 GHz was obtained for the operating second-harmonic mode either by magnetic field tuning or beam voltage tuning. Long-term CW operation was evaluated during an uninterrupted period of 48 h, where the gyrotron output power and frequency were kept stable to within ±0.7% and ±6 ppm, respectively, by a computerized control system. Proper operation of an internal quasi-optical mode converter implemented to transform the operating whispering-gallery mode to a Gaussian-like beam was also verified. Based on the images of the gyrotron output beam taken with a pyroelectric camera, the Gaussian-like mode content of the output beam was computed to be 92% with an ellipticity of 12%.
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Affiliation(s)
- Antonio C. Torrezan
- Department of Electrical Engineering and Computer Science and the Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Seong-Tae Han
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA. He is now with the Korea Electrotechnology Research Institute, Ansan 426-170, Korea
| | - Ivan Mastovsky
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Michael A. Shapiro
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Jagadishwar R. Sirigiri
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Richard J. Temkin
- Department of Physics and the Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Alexander B. Barnes
- Department of Chemistry and the Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Robert G. Griffin
- Department of Chemistry and the Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
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Wright JT, Frazier-Bowers S, Simmons D, Alexander K, Crawford P, Han ST, Hart PS, Hart TC. Phenotypic variation in FAM83H-associated amelogenesis imperfecta. J Dent Res 2009; 88:356-60. [PMID: 19407157 DOI: 10.1177/0022034509333822] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
FAM83H gene mutations are associated with autosomal-dominant hypocalcified amelogenesis imperfecta (ADHCAI), which is typically characterized by enamel having normal thickness and a markedly decreased mineral content. This study tested the hypothesis that there are phenotype and genotype associations in families with FAM83H-associated ADHCAI. Seven families segregating ADHCAI (147 individuals) were evaluated. Phenotyping included clinical, radiographic, histological, and biochemical studies, and genotyping was by mutational analysis. Multiple novel FAM83H mutations were identified, including two 2-bp-deletion mutations, the first non-nonsense mutations identified. Craniofacial deviation from normal was more prevalent in the affected individuals. Affected individuals having truncating FAMH3H mutations of 677 or fewer amino acids presented a generalized ADHCAI phenotype, while those having mutations capable of producing a protein of at least 694 amino acids had a unique and previously unreported phenotype affecting primarily the cervical enamel. This investigation shows that unique phenotypes are associated with specific FAM83H mutations.
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Affiliation(s)
- J T Wright
- Dept. of Pediatric Dentistry, School of Dentistry, CB #7450 Brauer Hall, UNC Chapel Hill, NC 27599, USA.
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Hart PS, Becerik S, Cogulu D, Emingil G, Ozdemir-Ozenen D, Han ST, Sulima PP, Firatli E, Hart TC. Novel FAM83H mutations in Turkish families with autosomal dominant hypocalcified amelogenesis imperfecta. Clin Genet 2009; 75:401-4. [PMID: 19220331 DOI: 10.1111/j.1399-0004.2008.01112.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Han ST, Comfoltey EN, Shapiro MA, Sirigiri JR, Tax DS, Temkin RJ, Woskov PP, Rasmussen DA. Low-Power Testing of Losses in Millimeter-Wave Transmission Lines for High-Power Applications. Int J Infrared Millimeter Waves 2008; 29:1011-1018. [PMID: 19081774 DOI: 10.1007/s10762-008-9404-3] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We report the measurement of small losses in transmission line (TL) components intended for high-power millimeter-wave applications. Measurements were made using two different low-power techniques: a coherent technique using a vector network analyzer (VNA) and an incoherent technique using a radiometer. The measured loss in a 140 GHz 12.7 mm diameter TL system, consisting of 1.7 m of circular corrugated waveguide and three miter bends, is dominated by the miter bend loss. The measured loss was 0.3±0.1 dB per miter bend using a VNA; and 0.22±0.1 dB per miter bend using a radiometer. Good agreement between the two measurement techniques implies that both are useful for measuring small losses. To verify the methodology, the VNA technique was employed to measure the extremely small transmission loss in a 170 GHz ITER prototype TL system consisting of three lengths of 1 m, 63.5 mm diameter, circular corrugated waveguide and two miter bends. The measured loss of 0.05±0.02 dB per miter bend may be compared with the theoretical loss of 0.027 dB per miter bend. These results suggest that low-power testing of TL losses, utilizing a small, simple TL system and a VNA, is a reliable method for evaluating performance of low-loss millimeter-wave TL components intended for use in high-power applications.
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Affiliation(s)
- S T Han
- Plasma Science and Fusion Center, MIT, Cambridge, MA 02139-4294, USA; Korea Electrotechnology Research Institute, Changwon, Kyungnam 641-120, Republic of Korea
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Han ST, Griffin RG, Hu KN, Joo CG, Joye CD, Sirigiri JR, Temkin RJ, Torrezan AC, Woskov PP. Spectral Characteristics of a 140-GHz Long-Pulsed Gyrotron. IEEE Trans Plasma Sci IEEE Nucl Plasma Sci Soc 2007; 35:559-564. [PMID: 19081779 PMCID: PMC2600513 DOI: 10.1109/tps.2007.896931] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Gyrotrons operating in the millimeter and submillimeter wavelength ranges are the promising sources for applications that are requiring good spectral characteristics and a wide range of output power. We report the precise measurement results of gyrotron spectra. Experiments were conducted using a 140-GHz long-pulse gyrotron that is developed for the dynamic nuclear polarization/nuclear-magnetic-resonance spectroscopy at the Massachusetts Institute of Technology. Transient downshift of the frequency by 12 MHz with a time constant of 3 s was observed. After reaching equilibrium, the frequency was maintained within 1 ppm for over 20 s. The coefficient of the frequency change with cavity temperature was -2.0 MHz/K, which shows that fine tuning of the gyrotron frequency is plausible by cavity-temperature control. Frequency pulling by the beam current was observed, but it was shown to be masked by the downward shift of the gyrotron frequency with temperature. The linewidth was measured to be much less than 1 MHz at 60 dB relative to the carrier power [in decibels relative to carrier (dBc)] and 4.3 MHz at 75 dBc, which is the largest dynamic range to date for the measurement of gyrotron linewidth to our knowledge.
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Affiliation(s)
- Seong-Tae Han
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139-4294 USA
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Han ST, Griffin RG, Hu KN, Joo CG, Joye CD, Mastovsky I, Shapiro MA, Sirigiri JR, Temkin RJ, Torrezan AC, Woskov PP. Continuous-wave Submillimeter-wave Gyrotrons. Proc SPIE Int Soc Opt Eng 2006; 6373:63730C. [PMID: 17404605 PMCID: PMC1847421 DOI: 10.1117/12.686436] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Recently, dynamic nuclear polarization enhanced nuclear magnetic resonance (DNP/NMR) has emerged as a powerful technique to obtain significant enhancements in spin spectra from biological samples. For DNP in modern NMR systems, a high power continuous-wave source in the submillimeter wavelength range is necessary. Gyrotrons can deliver tens of watts of CW power at submillimeter wavelengths and are well suited for use in DNP/NMR spectrometers. To date, 140 GHz and 250 GHz gyrotrons are being employed in DNP spectrometer experiments at 200 MHz and 380 MHz at MIT. A 460 GHz gyrotron, which has operated with 8 W of CW output power, will soon be installed in a 700 MHz NMR spectrometer. High power radiation with good spectral and spatial resolution from these gyrotrons should provide NMR spectrometers with high signal enhancement through DNP. Also, these tubes operating at submillimeter wavelengths should have important applications in research in physics, chemistry, biology, materials science and medicine.
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Affiliation(s)
- Seong-Tae Han
- Plasma Science and Fusion Center, MIT, Cambridge, MA, USA 02139-4294
| | | | - Kan-Nian Hu
- Francis Bitter Magnet Laboratory, MIT, Cambridge, MA 02139-4294
| | - Chan-Gyu Joo
- Francis Bitter Magnet Laboratory, MIT, Cambridge, MA 02139-4294
| | - Colin D. Joye
- Plasma Science and Fusion Center, MIT, Cambridge, MA, USA 02139-4294
| | - Ivan Mastovsky
- Plasma Science and Fusion Center, MIT, Cambridge, MA, USA 02139-4294
| | | | | | - Richard J. Temkin
- Plasma Science and Fusion Center, MIT, Cambridge, MA, USA 02139-4294
| | | | - Paul P. Woskov
- Plasma Science and Fusion Center, MIT, Cambridge, MA, USA 02139-4294
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Han ST. Health informatics in the Western Pacific Region of WHO--current issues and concerns. Stud Health Technol Inform 1999; 52 Pt 1:suppl 15-7. [PMID: 10384546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Affiliation(s)
- S T Han
- WHO Regional Office for the Western Pacific, Manila, Philippines
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Han ST. "WHO's efforts: past, present and future--special reference to the proposal documents: new horizons in health". Tokai J Exp Clin Med 1997; 22:179-81. [PMID: 9670417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Han ST. STD / AIDS -- the need for a global response. Venereology 1995; 8:211-3. [PMID: 12291197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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Han ST. Demand and needs on new health initiative leaders developments. Tokai J Exp Clin Med 1995; 20:185-8. [PMID: 8863384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Han ST, Erben R. Health promotion in the western Pacific region of WHO. A programme outline. Promot Educ 1993; Spec No:36-41. [PMID: 8186943 DOI: 10.1177/175797599300100411] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- S T Han
- WHO Regional Office, Western Pacific, Manila, Philippines
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Han ST, Tsao YL, Walser RM, Becker MF. Electromagnetic scattering of two-dimensional surface-relief dielectric gratings. Appl Opt 1992; 31:2343-2352. [PMID: 20720899 DOI: 10.1364/ao.31.002343] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We employed the rigorous vector coupled-wave theory [J. Opt. Soc. Am. 73, 1105 (1983)] to analyze the electromagnetic scattering from two dimensional (2-D) surface-relief dielectric gratings. A shoot-back method was developed for the numerical solution of the resulting coupled differential equations. This method allowed numerical solutions to be found for grating structures of arbitrary profiles and relatively deep grooves. It was most suitable where the grating medium refractive index was not too large and where only a small number of propagating orders existed. Experiments confirmed the numerically predicted reflectivities for 2-D surface-relief dielectric sinusoidal gratings. Reflectivity measurements were made on 2-D sinusoidal gratings fabricated on photoresist and on polycarbonate. The grating periodicities were of the order of 3000 lines/mm such that only the zero-order diffracted waves were propagating in the incident region, and possibly a few forward orders in the transmission region. The embossing technique that was used for replicating the grating patterns from photoresist onto polycarbonate proved to be a feasible method for the production of such gratings.
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Han ST. Environmental health impacts of rapid industrialization and urbanization. J Hum Ergol (Tokyo) 1990; 19:249-51. [PMID: 2130097] [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: 12/30/2022]
Affiliation(s)
- S T Han
- WHO Regional Office for the Western Pacific, Manila, Philippines
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Han ST, Mei MH. [Effects of calcium ion on contractile response of guinea-pig gallbladder muscle strip to agonists]. Sheng Li Xue Bao 1990; 42:284-8. [PMID: 1964510] [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: 12/29/2022]
Abstract
The effects of calcium ion on the contractile response of gallbladder muscle strip (GBMS) in guinea pigs to acetylcholine, carbachol and caerulein were investigated by method of isotonic contraction and by RIA of cGMP and cAMP in the tissue. It was shown that the contractile response of GBMS to these agonists was stronger in Krebs solution than that in the calcium-free solution. In calcium-free solution, EDTA-zero calcium solution or verapamil-Krebs solution, the contractile response of GBMD was decreased to about 30% of the control (P less than 0.01). Verapamil significantly decreased carbachol induced enhancement of cGMP and cAMP of gallbladder tissue (P less than 0.01 or 0.05). The results suggest that both extra-and intra- cellular calcium take part in the contractile response of GBMS to agonists.
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Affiliation(s)
- S T Han
- Department of Physiology, Dalian Medical College
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Han ST. New initiatives in health manpower development in the western Pacific regional office of WHO. Asia Pac J Public Health 1989; 3:192-4. [PMID: 2620018 DOI: 10.1177/101053958900300303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Douglass KH, Tibbits P, Kasecamp W, Han ST, Koller D, Links JM, Wagner HN. Performance of a fully automated program for measurement of left ventricular ejection fraction. Eur J Nucl Med 1982; 7:564-6. [PMID: 6897632 DOI: 10.1007/bf00571652] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A fully automated program developed by us for measurement of left ventricular ejection fraction from equilibrium gated blood pool studies was evaluated in 130 additional patients. Both 6-min (130 studies) and 2-min (142 studies in 31 patients) gated blood pool studies were acquired and processed. The program successfully generated ejection fractions in 86% of the studies. These automatically generated ejection fractions were compared with ejection fractions derived from manually drawn regions of interest. When studies were acquired for 6-min with the patient at rest, the correlation between automated and manual ejection fractions was 0.92. When studies were acquired for 2-min, both at rest and during bicycle exercise, the correlation was 0.81. In 25 studies from patients who also underwent contrast ventriculography, the program successfully generated regions of interest in 22 (88%). The correlation between the ejection fraction determined by contrast ventriculography and the automatically generated radionuclide ejection fraction was 0.79.
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Harrison KS, Liu X, Han ST, Camargo EE, Wagner HN. Evaluation of a miniature CdTe detector for monitoring left ventricular function. Eur J Nucl Med 1982; 7:204-6. [PMID: 7094922 DOI: 10.1007/bf00256464] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A miniature CdTe probe interfaced to a microcomputer was used to measure left ventricular ejection fraction (LVEF) in 25 patients. LVEF obtained with the CdTe module, in the beat-to-beat mode, or the integrated gated mode agreed well with LVEF obtained with a gamma camera (r = 0.80; r = 0.82 respectively). Similarly, LVEF by CdTe probe agreed with LVEF obtained by gated equilibrium studies performed with a computerized NaI probe. The CdTe probe can provide comparable measurement of LVEF at a fraction of the cost of a camera-computer system and, being small and lightweight, the CdTe probe is adaptable for monitoring patients in intensive care facilities.
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