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Lee DK, Lee SC, Seol YG, Ahn JH, Lee NE, Kim YJ. Deformation characteristics of an organic thin film transistor. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2011; 11:239-242. [PMID: 21446433 DOI: 10.1166/jnn.2011.3259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An organic thin film transistor (OTFT) on a flexible substrate with electroplated electrodes has many advantages in the fabrication of low cost sensors, e-paper, smart cards, and flexible displays. In this study, we simulated the mechanical characteristics of an OTFT with various compressive stress conditions using COMSOL. An analysis model, which was limited to channel, source, and drain, was used to investigate deformation and internal stress concentrations. The channel length is 40 microm and the OTFT structure is a top-contact structure. The OTFT was fabricated using pentacene as a semiconducting layer and electroplated Ni as a gate electrode. The deformation characteristics of the fabricated OTFT were predicted in terms of strain and internal stress.
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Lee CH, Lee GW, Kang WK, Lee DK, Ko MJ, Kim KK, Park NG. Suppression of Charge Recombination Rate in Nanocrystalline SnO2by Thin Coatings of Divalent Oxides in Dye-Sensitized Solar Cells. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.11.3093] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Yoo B, Kim KJ, Lee DK, Kim K, Ko MJ, Kim YH, Kim WM, Park NG. Method to protect charge recombination in the back-contact dye-sensitized solar cell. OPTICS EXPRESS 2010; 18 Suppl 3:A395-A402. [PMID: 21165069 DOI: 10.1364/oe.18.00a395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We prepared a back-contact dye-sensitized solar cell and investigated effect of the sputter deposited thin TiO₂ film on the back-contact ITO electrode on photovoltaic property. The nanocrystalline TiO₂ layer with thickness of about 11 μm formed on a plain glass substrate in the back-contact structure showed higher optical transmittance than that formed on an ITO-coated glass substrate, which led to an improved photocurrent density by about 6.3%. However, photovoltage was found to decrease from 817 mV to 773 mV. The photovoltage recovered after deposition of a 35 nm-thick thin TiO₂ film on the surface of the back-contact ITO electrode. Little difference in time constant for electron transport was found for the back-contact ITO electrodes with and without the sputter deposited thin TiO₂ film. Whereas, time constant for charge recombination increased after introduction of the thin TiO₂ film, indicating that such a thin TiO₂ film protected back electron transfer, associated with the recovery of photovoltage. As the result of the improved photocurrent density without deterioration of photovoltage, the back-contact dye-sensitized solar cell exhibited 13.6% higher efficiency than the ITO-coated glass substrate-based dye-sensitized solar cell.
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Hartmann P, Lee DK, Smarsly B, Janek J. Mesoporous TiO2 Photoelectrodes for Solar Hydrogen Generation. Z Anorg Allg Chem 2010. [DOI: 10.1002/zaac.201008026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hartmann P, Lee DK, Smarsly BM, Janek J. Mesoporous TiO(2): comparison of classical sol-gel and nanoparticle based photoelectrodes for the water splitting reaction. ACS NANO 2010; 4:3147-54. [PMID: 20486697 DOI: 10.1021/nn1004765] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
This paper describes a systematic comparison of the photoelectrochemical properties of mesoporous TiO(2) films prepared by the two most prevalent templating methods: The use of preformed, crystalline nanoparticles is generally considered advantageous compared to the usage of molecular precursors such as TiCl(4), since the latter requires a separate heat treatment at elevated temperature to induce crystallization. However, our photoelectrochemical experiments clearly show that sol-gel derived mesoporous TiO(2) films cause an about 10 times higher efficiency for the water splitting reaction than their counterparts obtained from crystalline TiO(2) nanoparticles. This result indicates that for electrochemical applications the performance of nanoparticle-based metal oxide films might suffer from insufficient electronic connectivity.
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Yoo B, Kim K, Lee DK, Ko MJ, Lee H, Kim YH, Kim WM, Park NG. Enhanced charge collection efficiency by thin-TiO2-film deposition on FTO-coated ITO conductive oxide in dye-sensitized solar cells. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b926145a] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Paik YH, Kim JK, Lee JI, Kang SH, Kim DY, An SH, Lee SJ, Lee DK, Han KH, Chon CY, Lee SI, Lee KS, Brenner DA. Celecoxib induces hepatic stellate cell apoptosis through inhibition of Akt activation and suppresses hepatic fibrosis in rats. Gut 2009; 58:1517-27. [PMID: 19201774 DOI: 10.1136/gut.2008.157420] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIMS Activated hepatic stellate cells (HSCs) but not quiescent HSCs express cyclo-oxygenase-2 (COX-2), suggesting that the COX-2/prostanoid pathway has an active role in hepatic fibrogenesis. However, the role of COX-2 inhibitors in hepatic fibrogenesis remains controversial. The aim of this study was to investigate the antifibrotic effects of celecoxib, a selective COX-2 inhibitor. METHODS The effects of various COX inhibitors-that is, ibuprofen, celecoxib, NS-398 and DFU, were investigated in activated human HSCs. Then, the antifibrotic effect of celecoxib was evaluated in hepatic fibrosis developed by bile duct ligation (BDL) or peritoneal thioacetamide (TAA) injection in rats. RESULTS Celecoxib, NS-398 and DFU inhibited platelet-derived growth facor (PDGF)-induced HSC proliferation; however, only celecoxib (> or =50 microM) induced HSC apoptosis. All COX inhibitors completely inhibited prostaglandin E(2) (PGE(2)) and PGI(2) production in HSCs. Separately, PGE(2) and PGI(2) induced cell proliferation and extracellular signal-regulated kinase (ERK) activation in HSCs. All COX inhibitors attenuated ERK activation, but only celecoxib significantly inhibited Akt activation in HSCs. Celecoxib-induced apoptosis was significantly attenuated in HSCs infected with adenovirus containing a constitutive active form of Akt (Ad5myrAkt). Celecoxib had no significant effect on PPARgamma (peroxisome proliferator-activated receptor gamma) expression in HSCs. Celecoxib inhibited type I collagen mRNA and protein production in HSCs. Oral administration of celecoxib (20 mg/kg/day) significantly decreased hepatic collagen deposition and alpha-SMA (alpha-smooth muscle actin) expression in BDL- and TAA-treated rats. Celecoxib treatment significantly decreased mRNA expression of COX-2, alpha-SMA, transforming growth factor beta1 (TGFbeta1) and collagen alpha1(I) in both models. CONCLUSIONS Celecoxib shows a proapoptotic effect on HSCs through Akt inactivation and shows antifibrogenic effects in BDL- and TAA-treated rats, suggesting celecoxib as a novel antifibrotic agent of hepatic fibrosis.
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Lee DK, Kogel L, Ebbinghaus SG, Valov I, Wiemhoefer HD, Lerch M, Janek J. Defect chemistry of the cage compound, Ca12Al14O33−δ—understanding the route from a solid electrolyte to a semiconductor and electride. Phys Chem Chem Phys 2009; 11:3105-14. [PMID: 19370205 DOI: 10.1039/b818474g] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Valov I, Lee DK, De Souza RA, Martin M, Lerch M, Janek J. Defect Chemistry and Transport Properties of Nitrogen-Doped YSZ. Z Anorg Allg Chem 2008. [DOI: 10.1002/zaac.200870008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kucheyev SO, Biener J, Baumann TF, Wang YM, Hamza AV, Li Z, Lee DK, Gordon RG. Mechanisms of atomic layer deposition on substrates with ultrahigh aspect ratios. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:943-948. [PMID: 18166066 DOI: 10.1021/la7018617] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Atomic layer deposition (ALD) appears to be uniquely suited for coating substrates with ultrahigh aspect ratios (> or similar 10(3)), including nanoporous solids. Here, we study the ALD of Cu and Cu3N on the inner surfaces of low-density nanoporous silica aerogel monoliths. Results show that Cu depth profiles in nanoporous monoliths are limited not only by Knudsen diffusion of heavier precursor molecules into the pores, as currently believed, but also by other processes such as the interaction of precursor and reaction product molecules with pore walls. Similar behavior has also been observed for Fe, Ru, and Pt ALD on aerogels. On the basis of these results, we discuss design rules for ALD precursors specifically geared for coating nanoporous solids.
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Mulkey VR, Owens VN, Lee DK. Management of warm-season grass mixtures for biomass production in South Dakota USA. BIORESOURCE TECHNOLOGY 2008; 99:609-17. [PMID: 17349789 DOI: 10.1016/j.biortech.2006.12.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 12/21/2006] [Accepted: 12/21/2006] [Indexed: 05/14/2023]
Abstract
Switchgrass (Panicum virgatum L.), big bluestem (Andropogon gerardii Vitman), and indiangrass (Sorghastrum nutans (L.) Nash) are native warm-season grasses commonly used for pasture, hay, and conservation. More recently switchgrass has also been identified as a potential biomass energy crop, but management of mixtures of these species for biomass is not well documented. Therefore, the objectives of our study were to: (1) determine the effects of harvest timing and N rate on yield and biomass characteristics of established warm-season grass stands containing a mixture of switchgrass, big bluestem, and indiangrass, and (2) evaluate the impact of harvest management on species composition. Five N rates (0, 56, 112, and 224 kg ha(-1) applied annually in spring and 224 kg ha(-1) evenly split between spring and fall) and two harvest timings (anthesis and killing frost) were applied to plots at two South Dakota USA locations from 2001 to 2003. Harvesting once a year shortly after a killing frost produced the greatest yields with high concentrations of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) along with lower concentrations of total nitrogen (TN) and ash. This harvest timing also allowed for the greatest percentage of desirable species while maintaining low grass weed percentages. While N rates of 56 and 112 kg ha(-1) tended to increase total biomass without promoting severe invasion of grass and broadleaf weed species, N application did not always result in significant increases in biomass production. Based on these results, mixtures of switchgrass and big bluestem were well suited for sustainable biomass energy production. Furthermore, N requirements of these mixtures were relatively low thus reducing production input costs.
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Lee DK, Yoo HI. Electrical conductivity and oxygen nonstoichiometry of acceptor (Ga)-doped titania. Phys Chem Chem Phys 2008; 10:6890-8. [DOI: 10.1039/b811319j] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lee DK, Chung SK, Dhong HJ, Kim HY, Kim HJ, Bok KH. Focal hyperostosis on CT of sinonasal inverted papilloma as a predictor of tumor origin. AJNR Am J Neuroradiol 2007; 28:618-21. [PMID: 17416809 PMCID: PMC7977366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND PURPOSE To evaluate the CT characteristics of focal hyperostosis in patients with sinonasal inverted papilloma and to correlate these characteristics with the detection of the origins of tumors. MATERIALS AND METHODS Paranasal sinus and nasal cavity CT images of 76 patients were reviewed retrospectively to detect areas within which there was focal hyperostosis. We correlated the sites on the CT scans within which there was focal hyperostosis with the origin of the tumors described in the corresponding patient's medical records. We also evaluated the CT features of focal hyperostosis according to the origin of tumors. RESULT Surgical evaluation of 55 lesions with focal hyperostosis in CT images revealed that 49 of these lesions coincided with the actual origin of tumor. The CT-based determination of the locations of the areas of focal hyperostosis corresponded to the actual tumor origin in 89.1% of cases. Especially in cases with focal hyperostosis within the frontal, maxillary, sphenoid, and posterior ethmoid sinuses, areas of focal hyperostosis corresponded to the origin of tumor without exception. In the evaluation of the CT features of focal hyperostosis, 2 patterns of localized bone thickening were noted. Plaquelike bone thickening was seen mainly when focal hyperostosis involved the lateral wall of the nasal cavity. On the other hand, cone-shaped bone thickening was seen only in the walls of the paranasal sinuses or the bony septum. CONCLUSIONS A high correlation between the origin of the inverted papilloma and focal hyperostosis on CT might facilitate preoperative prediction of tumor origin by radiologists and rhinologists.
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Kim SI, Lee DK, Kim SY, Kwon OS, Cho J. An algorithm to detect a center of pupil for extraction of point of gaze. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:1237-40. [PMID: 17271912 DOI: 10.1109/iembs.2004.1403393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
This work proposes an algorithm that is developed for the video-oculograph method. It is used to detect a center of pupil for extraction of point of gaze in the eye image acquired by a charge coupled device camera and TV receiver card. The center of pupil could be detected accurately by applying the proposed algorithm in this study that removes noise effectively caused by eyelashes and image that is projected on pupil. In this study, we assume that the pupil is a perfect circle in the captured eye images.
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Lee DK, Kim SC, Yoon JH. Reuse of a dyehouse effluent after being treated with the combined catalytic wet peroxide oxidation process and the aerated constructed wetland. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2007; 55:407-15. [PMID: 17305165 DOI: 10.2166/wst.2007.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A catalytic wet peroxide oxidation process was combined with the aerated constructed wetland in order to treat the raw dyehouse wastewater to in acceptable level for reuse as washing process water. More than 90% of BOD and CODs could be removed with the wet peroxide oxidation reactor and the remaining pollutants in the treated water were transformed into biodegradable ones which could have been successfully treated at the following aerated constructed wetland. The highest values of BOD5, CODMn, CODCr, SS and T-N in the treated water were 1.6, 1.8, 2.1, 0.5 and 12.8 mg/L, respectively. These values were low enough for the treated water to be reused at the washing process.
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Cho YS, Lee DK, Hong SD, Oh WS. Intracranial aspergillosis involving the internal auditory canal and inner ear in an immunocompetent patient. AJNR Am J Neuroradiol 2007; 28:138-40. [PMID: 17213442 PMCID: PMC8134082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We report the MR imaging findings in a case of intracranial aspergillosis involving the internal auditory canal (IAC) and inner ear in an immunocompetent patient. The presence of rim enhancement of the vestibulocochlear nerve, abnormal signal intensity involving the labyrinth, and adjacent meningeal enhancement might help clinicians to make a correct diagnosis in patients with a mass in the IAC and previous history of ear surgery.
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Lee DK, Yoo HI. Electron-ion interference and Onsager reciprocity in mixed ionic-electronic transport in TiO2. PHYSICAL REVIEW LETTERS 2006; 97:255901. [PMID: 17280367 DOI: 10.1103/physrevlett.97.255901] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Indexed: 05/13/2023]
Abstract
Onsager's reciprocity theorem has been extensively discussed for fluid systems and its validity generally accepted. The application of the theorem to solid state, however, is not always transparent due to additional complications that have no counterparts in fluids, and its validity has not been so exhaustively examined experimentally either. Here we show that in the phenomenon of mixed ionic-electronic conduction in TiO2 (rutile), the theorem is verified experimentally, and the Onsager cross coefficient can be even larger than a direct one, contrary to the conventional belief.
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Kim EJ, Lee DK, Kang DH, Ku BD, Kim JS, Na DL, Lee JH. Ipsilateral Ptosis Associated with Anterior Thalamic Infarction. Cerebrovasc Dis 2005; 20:410-1. [PMID: 16210852 DOI: 10.1159/000088664] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2004] [Indexed: 11/19/2022] Open
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Chang SE, Lee DK, Choi JH, Moon KC, Koh JK. Majocchi's granuloma of the vulva caused by Trichophyton mentagrophytes. Mycoses 2005; 48:382-4. [PMID: 16262873 DOI: 10.1111/j.1439-0507.2005.01147.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report a case of Majocchi's granuloma caused by Trichophyton mentagrophytes on the vulva in a 23-year-old girl who had used topical steroids for many years. Her dog was a source of the infection.
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Narasimhaswamy T, Monette M, Lee DK, Ramamoorthy A. Solid-State NMR Characterization and Determination of the Orientational Order of a Nematogen. J Phys Chem B 2005; 109:19696-703. [PMID: 16853547 DOI: 10.1021/jp052343v] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thermotropic liquid crystalline compounds are of considerable importance due to their potential applications as advanced functional materials. A mesogen consisting of a terminal dimethylamino group, which can act as a charge-transfer donor, is particularly valuable for its light emission and nonlinear optical properties. In this study, we report the solid-state NMR investigation of the nematic behavior of one such novel mesogen (4-(dodecyloxy)benzoic acid 4-[((4-(dimethylamino)phenyl)imino)methyl]phenyl ester). Static and MAS experiments were performed on nematic and crystalline phases of the compound to measure (13)C chemical shift, (13)C-(1)H dipolar coupling, and (1)H chemical shift values. 2D chemical shift correlation of (1)H and (13)C nuclei confirmed the (13)C chemical shift values determined from 1D CPMAS experiments. The appearance of more peaks in both CPMAS and (13)C-(1)H HETCOR spectra of a crystalline solid suggests the heterogeneous orientations of phenyl rings of the mesogenic core. Variable-temperature experiments infer the motional averaging of these orientations before melting. The (1)H-(13)C dipolar coupling values, measured by 2D PITANSEMA experiments, were used to determine the orientational order of the mesogenic core at various temperatures. The influence of the linking unit and terminal substituents on the order parameter values of the mesogenic core is discussed.
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Yamamoto K, Ermakov VL, Lee DK, Ramamoorthy A. PITANSEMA-MAS, a solid-state NMR method to measure heteronuclear dipolar couplings under MAS. Chem Phys Lett 2005; 408:118-122. [PMID: 16652173 PMCID: PMC1451416 DOI: 10.1016/j.cplett.2005.04.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A 2D NMR method is presented for the measurement of the dipole-dipole interaction between a proton and a low-frequency nuclear spin species in the solid state under the magic angle spinning. It employs the time averaged nutation concept to dramatically reduce the required radio frequency (rf) power on the low γ nuclear channel and spin exchange at the magic angle is used to suppress (1)H-(1)H dipolar interactions and chemical shifts. The flexibility in choosing the spinning speed, rf power and the scaling factor of the pulse sequence are of considerable importance for the structural studies of biological solids. The performance of the pulse sequence has been numerically and experimentally demonstrated on several solids.
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Lee JY, Kim JI, Park JY, Choe JY, Kim CG, Chung SH, Lee DK, Chang HK. Cervical spine involvement in longstanding ankylosing spondylitis. Clin Exp Rheumatol 2005; 23:331-8. [PMID: 15971420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE To investigate the degree of ossification and the frequency of ankylosis between the atlas and the dens of the axis in patients with longstanding ankylosing spondylitis (AS), to assess radiological involvement of the cervical spine, and to determine their correlations with structural severity and clinical variables, including neurological abnormalities. METHODS In 61 AS patients with disease duration over 7 years, the findings of conventional radiographs were graded by the Bath Ankylosing Spondylitis Radiology Index (BASRI), and the ossification levels between the atlas and the dens and the severity of zygapophyseal (ZA) joint lesions were scored using multislice CT. Neurological examinations and somatosensory evoked potentials (SSEP) were performed by neurologists. RESULTS According to the BASRI, 50 patients (82.0%) had radiological changes of the cervical spine > or = score 1. Thirty-seven patients (60.6%) revealed a certain extent of the atlantodental ossification, and the presence of partial or complete atlantodental ankylosis was seen over 30% of the patients. The BASRI-cervical spine score and the atlantodental ossification levels correlated with disease duration. ZA involvement was observed in 49 patients (80.3%), including 23 with ZA fusion (37.7%). Although 4 of 11 patients with atlantoaxial subluxation showed abnormal SSEP none had significant neurological complications. This might be attributed in part to atlantodental ankylosis and ZA fusion. Finally, ossifications of the anterior and posterior longitudinal ligaments were found 26.2 and 29.5%, respectively. CONCLUSION Cervical spine involvement and atlantodental ossification or ankylosis appear to be common in patients with longstanding AS, and to be particularly more severe in patients with a longer disease duration.
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Lee DK, Suhler EB, Augustin W, Buggage RR. Serpiginous choroidopathy presenting as choroidal neovascularisation. Br J Ophthalmol 2003; 87:1184-5. [PMID: 12928294 PMCID: PMC1771863 DOI: 10.1136/bjo.87.9.1184] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Yoo HI, Lee DK. Chemical diffusion in complex oxides with an emphasis on BaTiO3. Phys Chem Chem Phys 2003. [DOI: 10.1039/b300169p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Odabasi Z, Demirci M, Kim DS, Lee DK, Ryan HF, Claussen GC, Tseng A, Oh SJ. Postexercise facilitation of reflexes is not common in Lambert-Eaton myasthenic syndrome. Neurology 2002; 59:1085-7. [PMID: 12370470 DOI: 10.1212/wnl.59.7.1085] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Postexercise facilitation (PEF) with clinical reflexes, H-reflex, and T-reflexes at the ankle and knee was systematically studied in 16 patients with Lambert-Eaton myasthenic syndrome (LEMS). PEF was observed in ankle and knee deep tendon reflexes in five patients, in H-reflex in three patients, and in T-reflexes in six patients. When all reflex tests were combined, 7 (43.7%) of 16 patients showed PEF by at least one test. The authors conclude that the PEF of reflexes, the most helpful diagnostic clinical marker for LEMS, is not common.
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