68 results on '"Sung Woo Lee"'
Search Results
2. Transportation strategy decision-making process using interval-valued complex fuzzy soft information.
- Author
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Naeem Jan, Jeonghwan Gwak, Juhee Choi, Sung Woo Lee, and Chul Su Kim
- Subjects
DECISION making ,SOFT sets ,TRANSPORTATION ,ECONOMIC development ,FUZZY sets - Abstract
Transportation is among the more vital economic activities for a business and our daily life actions. At present, transport is one of the key branches playing a crucial role in the development of the economy. Transportation decision-making looks for ways to solve current and anticipated transportation problems while avoiding future problems. An interval-valued complex fuzzy set (IVCFS) is an extended form of fuzzy, interval-valued fuzzy and complex fuzzy sets, and it is used to evaluate complex and inaccurate information in real-world applications. In this research, we aim to examine the novel concept of IVCF soft relations (IVCFSRs) by utilizing the Cartesian product (CP) of two IVCF soft sets (IVCFSSs), which are determined with the help of two different concepts, referred to as IVCF relation and soft sets. Moreover, we investigated various types of relations and also explained them with the help of some appropriate examples. The IVCFSRs have a comprehensive structure discussing due dealing with the degree of interval-valued membership with multidimensional variables. Moreover, IVCFSR-based modeling techniques are included, and they use the score function to select the suitable transportation strategy to improve the value of the analyzed data. Finally, to demonstrate the effectiveness of the suggested work, comparative analysis with existing methods is performed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. Left Ventricular Diastolic Dysfunction and Progression of Chronic Kidney Disease: Analysis of KNOW-CKD Data.
- Author
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Eunjeong Kang, Sung Woo Lee, Hyunjin Ryu, Minjung Kang, Seonmi Kim, Park, Sue K., Ji Yong Jung, Kyu‐Beck Lee, Seung Hyeok Han, Ahn, Curie, Kook‐Hwan Oh, Kang, Eunjeong, Lee, Sung Woo, Ryu, Hyunjin, Kang, Minjung, Kim, Seonmi, Jung, Ji Yong, Lee, Kyu-Beck, Han, Seung Hyeok, and Oh, Kook-Hwan
- Published
- 2022
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4. Clinical Value of Serum Mitochondria-Inhibiting Substances in Assessing Renal Hazards: A Community-Based Prospective Study in Korea.
- Author
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Hoon Sung Choi, Jin Taek Kim, Hong Kyu Lee, Wook Ha Park, Youngmi Kim Pak, and Sung Woo Lee
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ARYL hydrocarbon receptors ,KIDNEY physiology ,LONGITUDINAL method ,LOGISTIC regression analysis ,ADENOSINE triphosphate - Abstract
Background: Mitochondrial dysfunction is strongly associated with several kidney diseases. However, no studies have evaluated the potential renal hazards of serum mitochondria-inhibiting substance (MIS) and aryl hydrocarbon receptor ligand (AhRL) levels. Methods: We used serum level of MIS and AhRL and clinical renal outcomes from 1,511 participants of a prospective communitybased cohort in Ansung. MIS was evaluated based on intracellular adenosine triphosphate (MIS-ATP) or reactive oxygen species (MIS-ROS) generation measured using cell-based assays. Results: During a mean 6.9-year follow-up, 84 participants (5.6%) developed a rapid decline in kidney function. In the lowest quartile group of MIS-ATP, patients were older and had metabolically deleterious parameters. In multivariate logistic regression analysis, higher MIS-ATP was associated with decreased odds for rapid decline: the odds ratio (OR) of 1% increase was 0.977 (95% confidence interval [CI], 0.957 to 0.998; P=0.031), while higher MIS-ROS was marginally associated with increased odds for rapid decline (OR, 1.014; 95% CI, 0.999 to 1.028; P=0.055). However, serum AhRL was not associated with the rapid decline in kidney function. In subgroup analysis, the renal hazard of MIS was particularly evident in people with hypertension and low baseline kidney function. Conclusion: Serum MIS was independently associated with a rapid decline in kidney function, while serum AhRL was not. The clinical implication of renal hazard on serum MIS requires further evaluation in future studies. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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5. Reaction condition optimization for non-oxidative conversion of methane using artificial intelligence.
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Hyun Woo Kim, Sung Woo Lee, Na, Gyoung S., Seung Ju Han, Seok Ki Kim, Jung Ho Shin, Hyunju Chang, and Yong Tae Kim
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- 2021
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6. The Association between Pulmonary Functions and Incident Diabetes: Longitudinal Analysis from the Ansung Cohort in Korea.
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Hoon Sung Choi, Sung Woo Lee, Jin Taek Kim, and Hong Kyu Lee
- Subjects
GLYCOSYLATED hemoglobin ,GLUCOSE tolerance tests ,DIABETES ,MIDDLE-aged persons ,INSULIN resistance - Abstract
Background: We sought to explore whether reduced pulmonary function is an independent risk factor for incident diabetes in Koreans. Methods: We conducted a prospective cohort study of pulmonary function as a risk factor for incident diabetes using 10-year follow- up data from 3,864 middle-aged adults from the Ansung cohort study in Korea. The incidence of diabetes was assessed using both oral glucose tolerance tests and glycosylated hemoglobin levels. Results: During 37,118 person-years of follow-up, 583 participants developed diabetes (incidence rate: 15.7 per 1,000 personyears). The mean follow-up period was 8.0±3.7 years. Forced vital capacity (FVC; % predicted) and forced expiratory volume in 1 second (FEV1; % predicted) were significantly correlated with incident diabetes in a graded manner after adjustment for sex, age, smoking, exercise, and metabolic parameters. The adjusted hazard ratio (HR) and confidence interval (CI) for diabetes were 1.408 (1.106 to 1.792) and 1.469 (1.137 to 1.897) in the first quartiles of FVC and FEV1, respectively, when compared with the highest quartile. Furthermore, the FVC of the lowest first and second quartiles showed a significantly higher 10-year panel homeostasis model assessment of insulin resistance index, with differences of 0.095 (95% CI, 0.010 to 0.018; P=0.028) and 0.127 (95% CI, 0.044 to 0.210; P=0.003), respectively, when compared to the highest quartiles. Conclusion: FVC and FEV1 are independent risk factors for developing diabetes in Koreans. Pulmonary factors are possible risk factors for insulin resistance and diabetes. [ABSTRACT FROM AUTHOR]
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- 2020
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7. Research for improvement of the national evaluation program for emergency medical center in Korea.
- Author
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Kap Su Han, Won Young Kim, Su Jin Kim, Jinwoo Jeong, Hyunggoo Kang, Chulung Lee, and Sung Woo Lee
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CATASTROPHIC illness ,CRITICALLY ill ,CROWDS ,EMERGENCY medical services ,LENGTH of stay in hospitals ,HOSPITAL emergency services ,MEDICAL research ,PATIENTS ,QUALITY assurance ,EVALUATION of human services programs - Abstract
In Korea, the national evaluation program for emergency medical centers (EMCs) was introduced in 2003. EMCs in Korea have three levels of emergency centers including regional emergency centers, local emergency centers, and local emergency rooms. The evaluation system assesses the performance of EMCs at all three levels. The role of both regional emergency centers and local emergency centers administer the final treatment for severe emergency patients, although the definition of severe emergency patients is unclear. These factors may aggravate crowding at the emergency department. The national evaluation system aims to reduce the length of stay in the emergency department. However, reduction of the length of stay at emergency department may cause a conflict with the administration of final treatment for critically ill emergency patients owing to a lack of in-hospital beds. Crowding of the emergency department is not a problem of EMCs but that of the health system. In 2019, the Korean Society of Emergency Medicine performed a study to improve the national evaluation program for EMC and the performance of EMC. Here, we have summarized the results. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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8. Reliability and Characteristics of Current Perception Thresholds in the Territory of the Infraorbital and Inferior Alveolar Nerves.
- Author
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Hyung-Suk Kim, Hong-Seop Kho, Young-Ku Kim, Sung-Woo Lee, and Sung-Chang Chung
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THRESHOLD (Perception) ,ALVEOLAR nerve ,PAIN ,TRIGEMINAL nerve ,ALVEOLAR process ,NEUROLOGICAL disorders ,NEUROPATHY - Abstract
Aims: To estimate the intra- and interrater reliability of current perception threshold (CPT) evaluation, especially within the infraorbital nerve territory (ION) and inferior alveolar nerve territory (IAN) of the orofacial region, and to characterize the CPTs of ION and IAN in the normal population. Methods: Electrical stimulation (at 2.000 Hz, 250 Hz, and 5Hz) was applied to ION and IAN to allow for CPT evaluation in 200 subjects, all of whom were healthy, had no systemic diseases, and were free from symptoms and history of neuropathic conditions. Twenty-five of the subjects were evaluated 3 times by 2 examiners to test reliability, and the remaining subjects were evaluated once for normative data. Results: The intraclass correlation coefficient of CPTs within examiner and between examiners ranged from 0.46 to 0.95. There were no significant differences between right and left sides in CPT evaluation within the ION and IAN territory. Gender and age did not affect the CPT values for ION and IAN in the normal population. There were significant differences between each of the 3 frequency-dependent (2,000 Hz. 250 Hz, 5 Hz) measures within ION and IAN (P < 0.001). Conclusion: Evaluation of CPTs within ION and IAN revealed good intra- and interrater reliabflity. The study also provided normative data of CPTs of ION. IAN, and the between-site and within-site ratios of CPTs of ION and IAN. This should prove useful in the diagnosis of orofacial neuropathy. [ABSTRACT FROM AUTHOR]
- Published
- 2000
9. Sub-morbid dehydration-associated glomerular hyperfiltration: An emerging reality?
- Author
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Hyang Ki Min, Su Ah Sung, So Young Lee, and Sung Woo Lee
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Background: Severe dehydration decreases renal perfusion. However, it is unclear whether sub-morbid dehydration affects kidney function similarly. Although there have been numerous animal and human studies that have suggested mild dehydration is associated with glomerular hyperfiltration, it has not been confirmed on a large-scale in the general population. Therefore, we aimed to identify the relationship between hydration status and kidney function. Methods: We reviewed the data of 28,342 adults who participated in the Korea National Health and Nutrition Examination Surveys. Urine specific gravity unit (SGU) was the primary variable that indicated hydration status, and the estimated glomerular filtration rate (eGFR) was used as the primary outcome. Results: Multivariate linear regression analysis showed urine SGU was positively associated with eGFR, which was J-shaped in the multivariate generalized additive model plot. In the penalized spline curve analysis, the odds ratio for high eGFR was steadily increased. Although increased urine SGU was associated with decreased blood pressure and pulse rate, it had no effect on increased fasting glucose and total cholesterol, suggesting conflicting cardio-metabolic dehydration effects. Conclusion: Dehydration, presumably sub-morbid in an ambulatory community-dwelling general population, is associated with higher kidney function. The clinical significance of sub-morbid dehydration-associated glomerular hyperfiltration needs further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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10. Pain-Pressure Threshold in the Head and Neck Region of Episodic Tension-type Headache Patients.
- Author
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Hyung-Suk Kim, Sung-Chang Chung, Young-Ku Kim, and Sung-Woo Lee
- Subjects
MEDICAL research ,PAIN ,HEADACHE ,NECK pain ,MUSCLES ,MUSCULOSKELETAL system ,MULTIVARIATE analysis ,STERNOCLEIDOMASTOID muscle ,TRAPEZIUS muscle ,PATIENTS - Abstract
Copyright of Journal of Orofacial Pain is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 1995
11. National evaluation program for emergency medical center.
- Author
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Sung Woo Lee
- Subjects
EMERGENCY medical services ,HEALTH care rationing ,HOSPITAL emergency services ,MEDICAL quality control ,PATIENTS ,QUALITY assurance ,EVALUATION of human services programs - Abstract
Since 2003, the national evaluation program for emergency medical centers (EMCs) has been managed by the Central Emergency Medical center which is controlled by the Ministry of Health and Welfare. Although the evaluation system for EMC has contributed to the development of the structure of emergency centers and the expansion of emergency resources (emergency medical person and equipment), it has some limitations in terms of quality control for both EMCs and emergency medical systems. One of the purposes of the evaluation program is to assess the performance of EMC in different levels. However, both regional and local emergency centers have same role that is offering of final treatment to severe emergency patients. There is no role for local emergency rooms in the emergency care of patients. In addition, the national evaluation program does not have outcome indicators that assess the performance of the EMC in emergency care. The improvement of the national evaluation system for EMC is required for the appropriate assessment of the performance of EMCs in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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12. Proposed Imprecision Quality Goals for Urinary Albumin/Creatinine Ratio.
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Dae-Hyun Ko, Sung Woo Lee, Jungwon Hyun, Hyun Soo Kim, Min-Jeong Park, and Dong Hoon Shin
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ALBUMINS ,CREATININE ,ALBUMINURIA ,CONFIDENCE intervals ,BIOLOGICAL variation statistics - Abstract
Background: The urinary albumin/creatinine ratio (ACR) is an important indicator of albuminuria. We aimed to estimate ACR uncertainty and its impact on test results and proposed imprecision quality goals based on the estimated uncertainty. Methods: The combined ACR uncertainty was calculated using the individual uncertainties of urinary albumin and creatinine. ACR confidence intervals (CIs) were estimated based on the expanded uncertainty. When the CI contained the ACR category boundary (30 or 300 mg/g), the cases were considered ambiguous. Quality goals for ACR were suggested using the number of ambiguous cases among actual patient results. Results: The number of ambiguous cases resulting from the combined ACR uncertainty was higher than expected based on biological variation (BV) quality goals. When the ACR met BV quality specifications, we estimated that 4.8-15.5% of the results may have been misclassified. To minimize the number of ambiguous results, the minimum, desirable, and optimum quality goals were set at 34.0%, 18.0%, and 4.5%, respectively. Conclusions: We expressed ACR uncertainty using the uncertainties of urinary albumin and creatinine and assessed the impact of this combined uncertainty on the test results. Subsequently, we proposed imprecision quality goals for ACR based on ambiguous results. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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13. Targeted cardiopulmonary resuscitation training focused on the family members of high-risk patients at a regional medical center: A comparison between family members of high-risk and no-risk patients.
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Kap Su Han, Ji Sung Lee, Su Jin Kim, and Sung Woo Lee
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HEART disease risk factors ,HEART diseases ,THERAPEUTICS ,CARDIAC arrest ,CARDIOVASCULAR diseases ,CARDIOPULMONARY resuscitation ,EDUCATIONAL tests & measurements ,CARDIAC patients ,MARRIED women ,MEDICAL personnel ,MOTIVATION (Psychology) ,RESEARCH evaluation ,SURVEYS ,TELEPHONES ,EXTENDED families ,EDUCATIONAL attainment ,HEALTH literacy ,EVALUATION of human services programs ,CARDIOVASCULAR diseases risk factors - Abstract
Copyright of Turkish Journal of Trauma & Emergency Surgery / Ulusal Travma ve Acil Cerrahi Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
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14. A system-wide approach from the community to the hospital for improving neurologic outcomes in out-of-hospital cardiac arrest patients.
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Won Sook Hwang, Jong Su Park, Su Jin Kim, Yun Sik Hong, Sung Woo Moon, and Sung Woo Lee
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- 2017
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15. Neural Probes for Chronic Applications.
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Geon Kook, Sung Woo Lee, Hyunjoo Jenny Lee, Hee Chul Lee, and Il-Joo Cho
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BRAIN mapping ,MICROFABRICATION ,FOREIGN body reaction - Abstract
Developed over approximately half a century, neural probe technology is now a mature technology in terms of its fabrication technology and serves as a practical alternative to the traditional microwires for extracellular recording. Through extensive exploration of fabrication methods, structural shapes, materials, and stimulation functionalities, neural probes are now denser, more functional and reliable. Thus, applications of neural probes are not limited to extracellular recording, brain-machine interface, and deep brain stimulation, but also include a wide range of new applications such as brain mapping, restoration of neuronal functions, and investigation of brain disorders. However, the biggest limitation of the current neural probe technology is chronic reliability; neural probes that record with high fidelity in acute settings often fail to function reliably in chronic settings. While chronic viability is imperative for both clinical uses and animal experiments, achieving one is a major technological challenge due to the chronic foreign body response to the implant. Thus, this review aims to outline the factors that potentially affect chronic recording in chronological order of implantation, summarize the methods proposed to minimize each factor, and provide a performance comparison of the neural probes developed for chronic applications. [ABSTRACT FROM AUTHOR]
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- 2016
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16. Neutron intensity modulation and time-focusing with integrated Larmor and resonant frequency techniques.
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Jinkui Zhao, Hamilton, William A., Sung-Woo Lee, Robertson, J. L., Crow, Lowell, and Kang, Yoon W.
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NEUTRON diffraction ,LARMOR frequency ,INELASTIC neutron scattering ,SIGNAL separation ,NUCLEAR spin - Abstract
The analysis of neutron diffraction experiments often assumes that neutrons are elastically scattered from the sample. However, there is growing evidence that a significant fraction of the detected neutrons is in fact inelastically scattered, especially from soft materials and aqueous samples. Ignoring these inelastic contributions gives rise to inaccurate experimental results. To date, there has been no simple method with broad applicability for inelastic signal separation in neutron diffraction experiments. Here, we present a simple and robust method that we believe could be suited for this purpose. We use two radio frequency resonant spin flippers integrated with a Larmor precession field to modulate the neutron intensity and to encode the inelastic scattering information into the neutron data. All three components contribute to the spin encoding. The Larmor field serves several additional purposes. Its usage facilitates neutron time-focusing, eliminates the need for stringent magnetic shielding, and allows for compact setups. The scheme is robust, simple, and flexible. We believe that, with further improvements, it has the potential of adding inelastic signal discrimination capabilities to many existing diffraction instruments in the future. [ABSTRACT FROM AUTHOR]
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- 2015
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17. A Polarization Diversity Patch Antenna with a Reconfigurable Feeding Network.
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Sung Woo Lee and Youngje Sung
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ANTENNAS (Electronics) ,POLARIZATION (Electricity) ,PIN diodes - Abstract
This paper proposes a reconfigurable square-patch antenna with polarization diversity. The proposed antenna consists of a square radiating patch and a Y-shaped feed structure with two PIN diodes. The shape of the feed structure can be changed by adjusting the bias states of the two PIN diodes, which helps switch between two orthogonal linear polarizations. The polarization diversity characteristic is validated by the simulated current distribution and the measured radiation pattern. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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18. A 10b linear interpolation DAC using body-transconductance control for AMLCD column driver.
- Author
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Changbyung Park, Ki-Duk Kim, Sung-Woo Lee, Gyu-Sung Park, Seung-Tak Ryu, and Gyu-Hyeong Cho
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- 2010
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19. Single cell assay on cd-like lab chip using centrifugal single cell trap.
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Sung-Woo Lee, In-Hye Lee, Sung-Shin Ryu, Seung-Min Kwak, Kyeong-Sik Shin, Ji-Yoon Kang, Hyo-Il Jung, and Tae-Song Kim
- Published
- 2007
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20. Evaluation of optimum position and orientation of laptop MIMO antennas using envelope correlation coefficients and mutual coupling parameters.
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Sung-Woo Lee, Fathy, A.E., El-Ghazaly, S.M., and Nair, V.
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- 2007
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21. A Study on Factors Affecting Patent Citation Counts and Patent Licensing in Chemistry Field.
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Yong-Gil Lee, Jeong-Dong Lee, Yong-Il Song, Yun-Chul Chung, and Sung-Woo Lee
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- 2006
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22. An optimal transition time to extracorporeal cardiopulmonary resuscitation for predicting good neurological outcome in patients with out-of-hospital cardiac arrest: a propensity-matched study.
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Su Jin Kim, Jae Seung Jung, Jae Hyoung Park, Jong Su Park, Yun Sik Hong, and Sung Woo Lee
- Published
- 2014
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23. Structural and Luminescence Properties of 6-Oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl thiophene-2-carboxylate.
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Yong-Kwang Jeong, Min-Ah Kim, Hyo-Sung Lee, Sung Woo Lee, and Jun-Gill Kang
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PYRIDONE ,CARBAZOLE derivatives ,LUMINESCENCE ,THIOPHENES ,ULTRAVIOLET radiation - Abstract
The article discusses a study on the structural and luminiscence properties as a series of pyrido [3,2,1-jk]carbazol-6-one (PCO) derivatives. Topics discussed include the production of deep-blue and blue-green luminescence by 4-hydroxy-5-phenyl-tH-pyridol [3,2,1-jk]-carbazol-6-one (HPPCO) and its derivative 6-oxo-5-phenyl-6H-pyrido [3,2,1-jk] carbazol-4-yl thiophene-2-carboxyate (OPPCT) respectively when exposed to UV light.
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- 2014
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24. International Cooperation and the Logistics Market in Northeast Asia: Problems and Prospects for North Korea.
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Seong-gul Hong, Sung-woo Lee, and Sung-jun Park
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BUSINESS logistics ,ECONOMIC change ,POLITICAL change ,NORTH Korean politics & government, 2011- ,ECONOMIC history - Abstract
The article discusses how structural changes and international cooperation in the Northeast Asian logistics market can effect political and economic change in North Korea. Topics covered include the Chang-Ji-Tu project, the Trans-Siberian Railway, and the northern sea route. Also mentioned are the Rason Special Economic Zone, the northern economic bloc, and the Trans-Korean Railway.
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- 2014
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25. Room temperature light-induced recrystallization of Cu2O cubes to CuO nanostructures in water.
- Author
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Yulyi Na, Sung Woo Lee, Roy, Nitish, Pradhan, Debabrata, and Youngku Sohn
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COPPER oxide ,COPPER compounds ,NANOWIRE crystallography ,CRYSTAL growth ,RECRYSTALLIZATION (Metallurgy) ,CRYSTALLOGRAPHY - Abstract
The mechanism of temperature-assisted Cu and Cu
2 O oxidation in oxygen and subsequent CuO nanowire growth is well known. Here, we report a simple light-induced process for the recrystallization of Cu2 O cubes to [010] growth-directed CuO nanoribbons in water at room temperature. This was attributed to the formation and participation of• OH and• O2 - active species in water as well as the outward diffusion of Cu ions leading to the formation of CuO nanoribbons along unstable {010} facets on the surface of Cu2 O cubes. The oxidation was significantly suppressed under dark conditions or by active species scavengers, confirming the strong role of visible light. CO oxidation activity of nanoribbons was found to be superior to that of cubes. Our unique light-induced recrystallization of Cu2 O to CuO in water provides new insight and better understanding of the oxidation mechanism of Cu2 O, enabling tailoring of nanostructures by varying types of light (sun, incandescent and fluorescent) and opening a new strategy for development of energy- and environment-related Cu oxide nanomaterials. [ABSTRACT FROM AUTHOR]- Published
- 2014
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26. A Groove Technique for Securing an Electrode Connector on the Cranial Bone : Case Analysis of Efficacy.
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Sung-Woo Lee, Myung-Ki Lee, Il Seo, Ho-Sang Kim, Jeong-Ho Kim, and Yun-Suk Kim
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DEEP brain stimulation ,SURGICAL complications ,CRANIOTOMY ,SKIN diseases ,FOLLOW-up studies (Medicine) - Abstract
Objective : A groove technique for securing an electrode connector was described as an alternative surgical technique in deep brain stimulation (DBS) surgery to avoid electrode connector-related complications, such as skin erosion, infection, and migration. Methods : We retrospectively reviewed 109 patients undergoing one of two techniques; the standard technique (52 patients using 104 electrodes) and the groove technique (57 patients using 109 electrodes) for securing the electrode connector in DBS surgery, regardless of patient disease. In the standard percutaneous tunneling technique, the connector was placed on the vertex of the cranial surface. The other technique, so called the groove technique, created a groove (about 4 cm long, 8 mm wide) in the cranial bone at the posterior parietal area. Wound erosion and migration related to the connectors were compared between the two techniques. Results : The mean follow-up period was 73 months for the standard method and 46 months for the groove technique. Connector-related complications were observed in three patients with the groove technique and in seven patients with the standard technique. Wound erosion at the connector sites per electrode was one (0.9%) with the groove technique and six (5.8%) with the standard technique. This difference was statistically significant. The electrode connector was migrated in two patients with the groove technique and in one patient with the standard technique. Conclusions : The groove technique, which involves securing an electrode using a groove in the cranial bone at the posterior parietal area, offers an effective and safe method to avoid electrode connector-related complications during DBS surgery. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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27. Effects of exogenous pyoverdines on Fe availability and their impacts on Mn(II) oxidation by Pseudomonas putida GB-1.
- Author
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Sung-Woo Lee, Parker, Dorothy L., Geszvain, Kati, and Tebo, Bradley M.
- Subjects
PYOVERDINES ,PSEUDOMONAS putida ,BIOFILMS ,MUTAGENESIS ,IRON - Abstract
Pseudomonas putida GB-1 is a Mn(II)-oxidizing bacterium that produces pyoverdine-type siderophores (PVDs), which facilitate the uptake of Fe(III) but also influence MnO
2 formation. Recently, a non-ribosomal peptide synthetase mutant that does not synthesize PVD was described. Here we identified a gene encoding the PVDGB-1 (PVD produced by strain GB-1) uptake receptor (PputGB1_4082) of strain GB-1 and confirmed its function by in-frame mutagenesis. Growth and other physiological responses of these two mutants and of wild type were compared during cultivation in the presence of three chemically distinct sets of PVDs (siderotypes n°1, n°2, and n°4) derived from various pseudomonads. Under iron-limiting conditions, Fe(III) complexes of various siderotype n°1 PVDs (including PVDGB-1 ) allowed growth of wild type and the synthetase mutant, but not the receptor mutant, confirming that iron uptake with any tested siderotype n°1 PVD depended on PputGB1_4082. Fe(III) complexes of a siderotype n°2 PVD were not utilized by any strain and strongly induced PVD synthesis. In contrast, Fe(III) complexes of siderotype n°4 PVDs promoted the growth of all three strains and did not induce PVD synthesis by the wild type, implying these complexes were utilized for iron uptake independent of PputGB1_4082. These differing properties of the three PVD types provided a way to differentiate between effects on MnO2 formation that resulted from iron limitation and others that required participation of the PVDGB-1 receptor. Specifically, MnO2 production was inhibited by siderotype n°1 but not n°4 PVDs indicating PVD synthesis or PputGB1_4082 involvement rather than iron-limitation caused the inhibition. In contrast, iron limitation was sufficient to explain the inhibition of Mn(II) oxidation by siderotype n°2 PVDs. Collectively, our results provide insight into how competition for iron via siderophores influences growth, iron nutrition and MnO2 formation in more complex environmental systems. [ABSTRACT FROM AUTHOR]- Published
- 2014
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28. Pyoverdine synthesis by the Mn(II)-oxidizing bacterium Pseudomonas putida GB-1.
- Author
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Parker, Dorothy L., Sung-Woo Lee, Geszvain, Kati, Davis, Richard E., Gruffaz, Christelle, Meyer, Jean-Marie, Torpey, Justin W., and Tebo, Bradley M.
- Subjects
PSEUDOMONAS putida ,PYOVERDINES ,SIDEROPHORES ,IRON chelates ,MICROBIAL metabolites - Abstract
When iron-starved, the Mn(II)-oxidizing bacteria Pseudomonas putida strains GB-1 and MnB1 produce pyoverdines (PVDGB?1 and PVDMnB1), siderophores that both influence iron uptake and inhibit manganese(II) oxidation by these strains. To explore the properties and genetics of a PVD that can affect manganese oxidation, LC-MS/MS, and various siderotyping techniques were used to identify the peptides of PVDGB?1 and PVDMnB1 as being (for both PVDs): chromophore-Asp-Lys-OHAsp-Ser-Gly-aThr-Lys-cOHOrn, resembling a structure previously reported for P. putida CFML 90-51, which does not oxidize Mn. All three strains also produced an azotobactin and a sulfonated PVD, each with the peptide sequence above, but with unknown regulatory or metabolic effects. Bioinformatic analysis of the sequenced genome of P. putida GB-1 suggested that a particular non-ribosomal peptide synthetase (NRPS), coded by the operon PputGB1_4083-4086, could produce the peptide backbone of PVDGB?1. To verify this prediction, plasmid integration disruption of PputGB1_4083 was performed and the resulting mutant failed to produce detectable PVD. In silico analysis of the modules in PputGB1_4083-4086 predicted a peptide sequence of Asp-Lys-Asp-Ser-Ala-Thr-Lsy-Orn, which closely matches the peptide determined by MS/MS. To extend these studies to other organisms, various Mn(II)-oxidizing and non-oxidizing isolates of P. putida, P. fluorescens, P. marincola, P. fluorescens-syringae group, P. mendocina-resinovorans group, and P. stutzerii group were screened for PVD synthesis. The PVD producers (12 out of 16 tested strains) were siderotyped and placed into four sets of differing PVD structures, some corresponding to previously characterized PVDs and some to novel PVDs. These results combined with previous studies suggested that the presence of OHAsp or the flexibility of the pyoverdine polypeptide may enable efficient binding of Mn(III). [ABSTRACT FROM AUTHOR]
- Published
- 2014
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29. Accuracy of transcutaneous carbon dioxide monitoring in hypotensive patients.
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Jung-Youn Kim, Young-Hoon Yoon, Sung-Woo Lee, Sung-Hyuk Choi, Young-Duck Cho, and Sang-Min Park
- Abstract
Objectives Continuous blood gas monitoring is frequently necessary in critically ill patients. Our aim was to assess the accuracy of transcutaneous CO
2 tension (PtcCO2 ) monitoring in the emergency department (ED) assessment of hypotensive patients by comparing it with the gold standard of arterial blood gas analysis (ABGA). Methods All patients receiving PtcCO2 monitoring in the ED were included. We excluded paediatric patients, patients with no ABGA results during a hypotensive event, patients whose ABGA was not performed simultaneously with PtcCO2 monitoring, and patients who received sodium bicarbonate for resuscitation. The included patients were classified into hypotensive patients and normotensive patients. A hypotensive patient was defined as a patient showing a mean arterial pressure under 60 mm Hg. The agreement in measurement between PaCO2 tension (PaCO2 ) and PtcCO2 were investigated in both groups. Results The mean difference between PaCO2 and PtcCO2 was 2.1 mm Hg, and the Bland-Altman limits of agreement (bias±1.96 SD) ranged from – 15.6 to 19.7 mm Hg in the 28 normotensive patients. The mean difference between PaCO2 and PtcCO2 was 1.1 mm Hg, and the Bland-Altman limits of agreement (bias±1.96 SD) ranged from –19.5 to 21.7 mm Hg in the 26 hypotensive patients. The weighted κ values were 0.64 in the normotensive patients and 0.60 in the hypotensive patients. Conclusions PtcCO2 monitoring showed wider limits of agreement with PaCO2 in urgent situations in the ED environment. However, acutely developed hypotension does not affect the accuracy of PtcCO2 monitoring. [ABSTRACT FROM AUTHOR]- Published
- 2014
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30. Antidotes of cyanide intoxication.
- Author
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Sung Woo Lee and Jun Sik Kim
- Subjects
ANTIDOTES ,CYANIDES ,POISONING ,SULFATES ,VITAMIN B12 ,THERAPEUTICS - Abstract
Cyanide poisoning can occur from industrial disasters, smoke inhalation from fire, food, and multiple other sources. Cyanide inhibits mitochondrial oxidative phosphorylation by blocking mitochondrial cytochrome oxidase, which in turn results in anaerobic metabolism and depletion of adenosine triphosphate in cells. Rapid administration of antidote is crucial for life saving in severe cyanide poisoning. Multiple antidotes are available for cyanide poisoning. The action mechanism of cyanide antidotes include formation of methemoglobin, production of less or no toxic complex, and sulfane sulfur supplementation. At present, the available antidotes are amyl nitrite, sodium nitrite, sodium thiosulfate, hydroxocobalamin, 4-dimethylaminophenol, and dicobalt edetate. Amyl nitrite, sodium nitrite, and 4-dimethylaminophenol induce the formation of methemoglobin. Sodium thiosulfate supplies the sulfane sulfur molecule to rhodanese, allowing formation of thiocyanate and regeneration of native enzymes. Hydroxocobalamin binds cyanide rapidly and irreversibly to form cyanocobalamin. Dicobalt edetate acts as a chelator of cyanide, forming a stable complex. Based on the best evidence available, a treatment regimen of 100% oxygen and hydroxocobalamin, with or without sodium thiosulfate, is recommended for cyanide poisoning. Amyl nitrite and sodium nitrite, which induce methemoglobin, should be avoided in victims of smoke inhalation because of serious adverse effects. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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- View/download PDF
31. Through-glass copper via using the glass reflow and seedless electroplating processes for wafer-level RF MEMS packaging.
- Author
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Ju-Yong Lee, Sung-Woo Lee, Seung-Ki Lee, and Jae-Hyoung Park
- Subjects
RADIO frequency microelectromechanical systems ,WAFER level packaging ,ELECTROPLATING ,COPLANAR waveguides ,THERMAL shock ,PRESSURE cooking ,EQUIPMENT & supplies - Abstract
We present a novel method for the fabrication of void-free copper-filled through-glass-vias (TGVs), and their application to the wafer-level radio frequency microelectromechanical systems (RF MEMS) packaging scheme. By using the glass reflow process with a patterned silicon mold, a vertical TGV with smooth sidewall and fine pitch could be achieved. Bottom-up void-free filling of the TGV is successfully demonstrated through the seedless copper electroplating process. In addition, the proposed process allows wafer-level packaging with glass cap encapsulation using the anodic bonding process, since the reflowed glass interposer is only formed in the device area surrounded with silicon substrate. A simple coplanar waveguide (CPW) line was employed as the packaged device to evaluate the electrical characteristics and thermo-mechanical reliability of the proposed packaging structure. The fabricated packaging structure showed a low insertion loss of 0.116 dB and a high return loss of 35.537 dB at 20 GHz, which were measured through the whole electrical path, including the CPW line, TGVs and contact pads. An insertion loss lower than 0.1 dB and a return loss higher than 30 dB could be achieved at frequencies of up to 15 GHz, and the resistance of the single copper via was measured to be 36 mΩ. Furthermore, the thermo-mechanical reliability of the proposed packaging structure was also verified through thermal shock and pressure cooker test. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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- View/download PDF
32. Mn(II,III) oxidation and MnO2 mineralization by an expressed bacterial multicopper oxidase.
- Author
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Butterfield, Cristina N., Soldatova, Alexandra V., Sung-Woo Lee, Spiro, Thomas G., and Tebo, Bradley M.
- Subjects
OXIDATION-reduction reaction ,OXIDE minerals ,REACTIVE oxygen species ,ORGANIC compounds ,COPPER oxide ,CHARGE exchange - Abstract
Reactive Mn(IV) oxide minerals are ubiquitous in the environment and control the bioavailability and distribution of many toxic and essential elements and organic compounds. Their formation is thought to be dependent on microbial enzymes, because spontaneous Mn(II) to Mn(IV) oxidation is slow. Several species of marine Bacillus spores oxidize Mn(II) on their exosporium, the outermost layer of the spore. encrusting them with Mn(IV) oxides. Molecular studies have identified the mnx (Mn oxidation) genes, including mnxG, encoding a putative multicopper oxidase (MCO), as responsible for this two-electron oxidation, a surprising finding because MCOs only catalyze single-electron transfer reactions. Characterization of the enzymatic mechanism has been hindered by the lack of purified protein. By purifying active protein from the mnxDEFG expression construct, we found that the resulting enzyme is a blue (absorption maximum 590 nm) complex containing MnxE, MnxF, and MnxG proteins. Further, by analyzing the Mn(II)and (III)-oxidizing activity in the presence of a Mn(III) chelator, pyrophosphate, we found that the complex facilitates both electron transfers from Mn (II) to Mn(III) and from Mn(III) to Mn(IV). X-ray absorption spectroscopy of the Mn mineral product confirmed its similarity to Mn(IV) oxides generated by whole spores. Our results demonstrate that Mn oxidation from soluble Mn(II) to Mn(IV) oxides is a two-step reaction catalyzed by an MCO-containing complex. With the purification of active Mn oxidase, we will be able to uncover its mechanism, broadening our understanding of Mn mineral formation and the bioinorganic capabilities of MCOs. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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- View/download PDF
33. The molecular biogeochemistry of manganese(II) oxidation.
- Author
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Geszvain, Kati, Butterfield, Cristina, Davis, Richard E., Madison, Andrew S., Sung-Woo Lee, Parker, Dorothy L., Soldatova, Alexandra, Spiro, Thomas G., Luther III, George W., and Tebo, Bradley M.
- Subjects
MANGANESE ,OXIDATION ,BIOGEOCHEMISTRY ,OXIDIZING agents ,OXIDATION-reduction reaction ,LIGANDS (Biochemistry) - Abstract
Micro-organisms capable of oxidizing the redox-active transition metal manganese play an important role in the biogeochemical cycle of manganese. In the present mini-review, we focus specifically on Mn(II)- oxidizing bacteria. The mechanisms by which bacteria oxidize Mn(II) include a two-electron oxidation reaction catalysed by a novel multicopper oxidase that produces Mn(IV) oxides as the primary product. Bacteria also produce organic ligands, such as siderophores, that bind to and stabilize Mn(III). The realization that this stabilized Mn(III) is present in many environments and can affect the redox cycles of other elements such as sulfur has made it clear that manganese and the bacteria that oxidize it profoundly affect the Earth's biogeochemistry. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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- View/download PDF
34. Acute traumatic coagulopathy decreased actual survival rate when compared with predicted survival rate in severe trauma.
- Author
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Su Jin Kim, Sung Woo Lee, Gap Su Han, Sung Woo Moon, Sung Hyuck Choi, and Yun Sik Hong
- Abstract
Objective To determine whether acute traumatic coagulopathy (ATC) should be combined with the trauma and injury severity score (TRISS) to predict outcome in severe trauma patients and investigate effects of the change in coagulation state during early resuscitation on the actual survival rate. Methods This was a retrospective study. Significant variables that affected 28-day mortality were analysed using multivariate logistic regression. Study patients were classified into three groups: no coagulopathy, mild coagulopathy or severe coagulopathy. Concordance between actual and predicted survival rates were compared for each group. The predicted survival rate was calculated using the TRISS method. The study also determined whether changes in the coagulation state during inhospital resuscitation affected the relationship between actual and predicted survival in patients who had rechecked coagulation profile within 12 h after presentation. Results Data from a total of 336 patients were analysed. At presentation, 20.8% of the study patients had mild coagulopathy, whereas 7.7% had severe coagulopathy. Age, injury severity score, revised trauma score and presence of ATC at presentation were independently associated with 28-day mortality. Actual survival was significantly lower than predicted survival in the mild and severe coagulopathy groups. Aggravation of coagulation state from normal or mild to severe coagulopathy or persistent severe coagulopathy during inhospital resuscitation mainly contributed to the discrepancy between actual and predicted survival. Conclusions ATC decreased actual survival more than expected. ATC should be combined with TRISS to predict trauma outcome in severely injured patients. Improvement in coagulopathy during resuscitation may reduce the incidence of preventable death after trauma. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
35. Radiological misinterpretations by emergency physicians in discharged minor trauma patients.
- Author
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Su-Jin Kim, Sung Woo Lee, Yun-Sik Hong, and Do-Hyoun Kim
- Abstract
Introduction Unerring radiological interpretation is essential in discharged minor trauma patients without follow-up visits based on the rapid decision of emergency physicians (EPs). Misinterpretation may raise issues concerning patient care, reimbursement and lawsuits. The authors investigated the discrepancies and associated factors in radiological interpretation for discharged trauma patients between EPs and radiologists. Methods The authors included trauma patients who visited the emergency department, from 1 August 2009 to 31 July 2010, and searched for cases showing discrepancy using the 'modified quality assurance model for radiological interpretation'. The overall/clinically significant discrepancy (CSD)/clinically insignificant discrepancy (CinSD) rates were calculated. The authors also looked at the relationship between discrepancies and several factors including age and time of visit. Results 10 243 cases were related to minor trauma, in which the radiological images were interpreted as normal by EPs. The overall discrepancy, the CSD and CinSD rates were 0.77% (n=79), 0.47% (n=48) and 0.3% (n=31), respectively. No discrepancy was shown to be related to the day or time of visit. The discrepancy rate turned out to be relatively higher with increasing age, and for injuries of the extremities. No associated factors were found between the CSD and CinSD groups. Conclusions Despite a relatively low CSD rate, careful interpretation is recommended considering age and body areas imaged. A modified model would be needed as a supportive tool for training and improving the quality of care. A further development of the modified system for efficient use of resources will be needed to focus on quality improvement and education in each hospital. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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- View/download PDF
36. Optimal entry points and trajectories for cervical pedicle screw placement into subaxial cervical vertebrae.
- Author
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Dong-Ho Lee, Sung-Woo Lee, Suk Jung Kang, Chang Ju Hwang, Nam Heun Kim, Ju-Yul Bae, Yung-Tae Kim, Choon Sung Lee, and Daniel Riew, K.
- Subjects
CERVICAL vertebrae diseases ,SPINAL surgery ,TRAJECTORY optimization ,SIMULATION methods & models - Abstract
The present study was performed to determine the optimal entry points and trajectories for cervical pedicle screw insertion into C3-7. The study involved 40 patients (M:F = 20:20) with various cervical diseases. A surgical simulation program was used to construct three-dimensional spine models from cervical spine axial CT images. Axial, sagittal, and coronal plane data were simultaneously processed to determine the ideal pedicle trajectory (a line passing through the center of the pedicle on coronal, sagittal, and transverse CT images). The optimal entry points on the lateral masses were then identified. Horizontal offsets and vertical offsets of the optimal entry points were measured from three different anatomical landmarks: the lateral notch, the center of the superior edge and the center of lateral mass. The transverse angle and sagittal angles of the ideal pedicle trajectory were measured. Using those entry points and trajectory results, virtual screws were placed into the pedicles using the simulation program, and the outcomes were evaluated. We found that at C3-6, the optimal entry point was located 2.0-2.4 mm medial and 0-0.8 mm inferior to the lateral notch. Since the difference of 1 mm is difficult to discern intra-operatively, for ease of remembrance, we recommend rounding off our findings to arrive at a starting point for the C3-6 pedicle screws to be 2 mm directly medial to the lateral notch. At C7, by contrast, the optimal entry point was 1.6 mm lateral and 2.5 mm superior to the center of lateral mass. Again, for ease of remembrance, we recommend rounding off these numbers to use a starting point for the C7 pedicle screws to be 2 mm lateral and 2 mm superior to the center of lateral mass. The average transverse angles were 45° at C3-5, 38° at C6, and 28° at C7. The entry points for each vertebra should be adjusted according to the transverse angles of pedicles. The mean sagittal angles were 7° upward at C3, and parallel to the upper end plate at C4-7. The simulation study showed that the entry point and ideal pedicle trajectory led to screw placements that were safer than those used in other studies. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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37. Characterization of a novel facultative Methylocystis species capable of growth on methane, acetate and ethanol.
- Author
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Jeongdae Im, Sung-Woo Lee, Sukhwan Yoon, DiSpirito, Alan A., and Semrau, Jeremy D.
- Subjects
BACTERIAL genetics ,BACTERIAL growth ,FATTY acids ,METHANE ,ACETATES ,ETHANOL - Abstract
Summary A non-motile strain of Methylocystis, strain SB2, isolated from a spring bog in southeast Michigan, had a curved rod morphology with a typical type II intracytoplasmic membrane system. This organism expressed the membrane-bound or particulate methane monooxygenase (pMMO) as well as a chalkophore with high affinity for copper and did not express the cytoplasmic or soluble methane monooxygenase (sMMO). Strain SB2 was found to grow within the pH range of 6-9, with optimal growth at 6.8. Growth was observed at temperatures ranging between 10°C and 30°C, with no growth at 37°C. The DNA G+C content was 62.9 mol%. Predominant fatty acids were 18:1ω7c (72.7%) and 18:1ω9c (24%) when grown on methane. Phylogenetic comparisons based on both pmoA and 16S rRNA sequences indicated that this organism belonged to the Methylocystis genus, and was closely related to Methylocystis rosea SV97
T and Methylocystis echinoides IMET10491T (98% 16S rRNA gene sequence similarity to both strains). DNA : DNA hybridizations indicated that strain SB2 had 70% similarity with M. rosea SV97T . Unlike M. rosea SV97T , strain SB2 was able to utilize not only methane for growth, but also ethanol and acetate. Furthermore, the predominant fatty acids in strain SB2 were different from those found in M. rosea SV97T , i.e. 54.2% and 39.7% of fatty acids are 18:1ω8 and 18:1ω7 in M. rosea SV97T , while 18:1ω8 is completely absent in strain SB2. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
38. Field application of nitrogen and phenylacetylene to mitigate greenhouse gas emissions from landfill cover soils: effects on microbial community structure.
- Author
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Jeongdae Im, Sung-Woo Lee, Bodrossy, Levente, Barcelona, Michael J., and Semrau, Jeremy D.
- Subjects
GREENHOUSE gases ,LANDFILLS ,NITROGEN ,MONOOXYGENASES ,AMMONIA - Abstract
Landfills are large sources of CH, but a considerable amount of CH can be removed in situ by methanotrophs if their activity can be stimulated through the addition of nitrogen. Nitrogen can, however, lead to increased NO production. To examine the effects of nitrogen and a selective inhibitor on CH oxidation and NO production in situ, 0.5 M of NHCl and 0.25 M of KNO, with and without 0.01% ( w/ v) phenylacetylene, were applied to test plots at a landfill in Kalamazoo, MI from 2007 November to 2009 July. Nitrogen amendments stimulated NO production but had no effect on CH oxidation. The addition of phenylacetylene stimulated CH oxidation while reducing NO production. Methanotrophs possessing particulate methane monooxygenase and archaeal ammonia-oxidizers (AOAs) were abundant. The addition of nitrogen reduced methanotrophic diversity, particularly for type I methanotrophs. The simultaneous addition of phenylacetylene increased methanotrophic diversity and the presence of type I methanotrophs. Clone libraries of the archaeal amoA gene showed that the addition of nitrogen increased AOAs affiliated with Crenarchaeal group 1.1b, while they decreased with the simultaneous addition of phenylacetylene. These results suggest that the addition of phenylacetylene with nitrogen reduces NO production by selectively inhibiting AOAs and/or type II methanotrophs. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
39. Design and implementation of a single bias FET source mixer.
- Author
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Sung-Woo Lee, Hwoa-Yuol Kim, and Hong-Goo Cho
- Published
- 1998
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- View/download PDF
40. Design Method for Area-efficient and Uniform Channel DACs in Current-mode AMOLED Display Data Drivers.
- Author
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Yong-Joon Jeon, Jin-Yong Jeon, Sung-Woo Lee, and Gyu-Hyeong Cho
- Subjects
LIGHT emitting diodes ,ELECTRIC currents ,COMPOSITE materials ,ELECTRONIC circuits ,POWER electronics - Abstract
A current-mode driving scheme has significant advantages over other competing driving method, and the scheme does not require the time-consuming threshold voltage sampling process used in recent voltage-mode driving methods. Design considerations for compact and uniform channel DACs in current-mode AMOLED display data drivers are addressed in detail. Furthermore, an 8 bit area-efficient cascaded-dividing DAC and a 9 bit segmented DAC are designed in accordance with the suggested DAC design method. The presented DACs perform outstandingly when compared in terms of a composite DAC performance that comprises chip area, power consumption, sampling frequency, and DAC bit resolution. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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- View/download PDF
41. Centrality and vulnerability in liner shipping networks: revisiting the Northeast Asian port hierarchy.
- Author
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Ducruet, Cesar, Sung-Woo Lee, and Ng, Adolf K. Y.
- Subjects
HARBORS ,SHIPYARDS ,COMMUNICATIONS industries - Abstract
This article is essentially an empirical investigation in the network analysis of inter-port traffic flows. Based on a database of vessel movements, it applies conventional techniques of network analysis to the graph of Northeast Asian liner networks in 1996 and 2006. Such an approach proves particularly helpful for analyzing the changing position of major hub ports and for revealing their respective tributary areas within the region. Despite rapid traffic growth at Chinese ports during the period under study, the latter seem to remain polarized by established hubs such as Korean ports and Hong Kong. This research reveals the strong relation between local port policies and the evolution of shipping network design. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
42. Risk factors for adjacent segment disease after lumbar fusion.
- Author
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Choon Sung Lee, Chang Ju Hwang, Sung-Woo Lee, Young-Joon Ahn, Yung-Tae Kim, Dong-Ho Lee, and Mi Young Lee
- Subjects
LUMBOSACRAL region ,DISEASE risk factors ,DEGENERATION (Pathology) ,MAGNETIC resonance imaging ,LOGISTIC regression analysis ,DISEASES - Abstract
The incidence of adjacent segment problems after lumbar fusion has been found to vary, and risk factors for these problems have not been precisely verified, especially based on structural changes determined by magnetic resonance imaging. The purpose of this retrospective clinical study was to describe the incidence and clinical features of adjacent segment disease (ASD) after lumbar fusion and to determine its risk factors. We assessed the incidence of ASD in patients who underwent lumbar or lumbosacral fusions for degenerative conditions between August 1995 and March 2006 with at least a 1-year follow-up. Patients less than 35 years of age at the index spinal fusion, patients with uninstrumented fusion, and patients who had not achieved successful union were excluded. Of the 1069 patients who underwent fusions, 28 (2.62%) needed secondary operations because of ASD and were included in this study. In order to identify the risk factors, we matched a disease group and a control group. The disease group consisted of 26 of the 28 patients with ASD, excluding the 2 patients for whom we did not have initial MRI data. Each patient in the disease group was matched by age, sex, fusion level and follow-up period with a control patient. The assumed risk factors included disc and facet degeneration, instability, listhesis, rotational deformity, and disc wedging. The mean age of the 28 patients with ASD requiring surgical treatment was 58.4 years, which did not differ significantly from that of the population in which ASD did not develop (58.2 years, p = 0.894). Of the 21 patients who underwent floating fusion, only 1 developed distal ASD. Facet degeneration was a significant risk factor ( p < 0.01) on logistic regression analysis. The incidence of distal ASD was much lower than that of proximal ASD. Pre-existing facet degeneration may be associated with a high risk of adjacent segment problems following lumbar fusion procedures. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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43. A Piecewise Linear 10 Bit DAC Architecture With Drain Current Modulation for Compact LCD Driver ICs.
- Author
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Yong-Joon Jeon, Hyung-Min Lee, Sung-Woo Lee, Gyu-Hyeong Cho, Hyoung Rae Kim, Yoon-Kyung Choi, and Myunghee Lee
- Subjects
LIQUID crystal displays ,ELECTRONIC data processing ,INTEGRATED circuits ,INTERPOLATION ,CAPACITORS ,ELECTRIC currents - Abstract
A piecewise linear 10 bit DAC for LCD data driver with robust interpolation method of drain current modulation is presented. It has higher effective bit resolution than the linear 10 bit switched-capacitor DAC when applied to nonlinear liquid crystal characteristics. By adopting a simultaneous design flow based on the estimations for the mismatch and nonlinearity effects on channel driver performance, the proposed DAC accomplishes good DNL of 0.37 LSB and excellent channel uniformity such that the mean and the standard deviation of the maximum output voltage deviations are 6.35 mV and 0.54 mV, respectively. The data driver with the new interpolation shows 8.2% shrinkage of chip area in comparison with the conventional 8 bit data driver with R-DAC. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
44. SPATIAL GLOCALIZATION IN ASIA-PACIFIC HUB PORT CITIES: A COMPARISON OF HONG KONG AND SINGAPORE.
- Author
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Sung- Woo Lee and Ducruet, Cesar
- Subjects
URBAN planning ,CITIES & towns ,HUMAN settlements ,URBAN sociology ,URBAN renewal ,URBAN life - Abstract
Port competition at both the regional and global scales results in port concentration and deconcentration, respectively. Whereas a number of recent studies interpret such phenomena as the effects of global forces such as containerization, few researchers have investigated local forces, such as the evolving relationships between urban policy and port growth. This study compares how two global hub port cities in the Asia-Pacific region, Hong Kong and Singapore, have sustained their port functions while transforming into major economic centers. Entropy indexes are calculated by district based on service industries related to port activities between 1993 and 2004. The results show the influences of port competition, lack of space, and congestion on changes in port-related activities. We conclude that cross-border integration is a main differentiating factor in the evolution of these hub port cities. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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- View/download PDF
45. Effects of atmospheric temperature and humidity on outbreak of diseases.
- Author
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Sung Hyuk Choi, Sung Woo Lee, Yun Sik Hong, Su Jin Kim, and Nak Hoon Kim
- Subjects
ATMOSPHERIC temperature ,HUMIDITY ,INFECTIOUS disease transmission ,DISEASE outbreaks ,LUNG diseases ,TRAUMATISM ,ETIOLOGY of diseases - Abstract
Objective: The present study aimed to determine the plausibility of forecasting the outbreak of diseases based on the weather by analysing the impact of atmospheric temperature and humidity on the occurrence of different diseases. Methods: The subjects of the present study were the 30 434 patients who visited the ED in 1 year from 1 February 2005 to 3 February 2006. The present study analysed the correlation between the daily number of patients who suffered from 22 types of traumatic and non-traumatic diseases and the data on atmospheric temperature and humidity provided by the Korea Meteorological Administration. Results: With traumatic disease, the occurrence tended to increase in proportion to the rise in temperature and humidity; whereas with non-traumatic disease, the occurrence tended to increase according to the rise in temperature, irrespective of humidity changes. The research on the impact of atmospheric temperature and humidity on different diseases revealed a high level of distribution of most diseases in an environment with high temperature and humidity. However, in the case of pulmonary diseases and trauma to multiple body regions, the occurrence increased in environments with low temperature and high humidity for pulmonary diseases, and with low temperature and low humidity for trauma to multiple body regions. Conclusion: Most diseases tend to increase in proportion to the rise in atmospheric temperature whereas being less affected by humidity. However, an increase in humidity in an optimum range of atmospheric temperature (12°C or higher) triggers an increase in the occurrence of diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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46. The Association between Pulmonary Functions and Incident Diabetes: Longitudinal Analysis from the Ansung Cohort in Korea.
- Author
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Hoon Sung Choi, Sung Woo Lee, Jin Taek Kim, and Hong Kyu Lee
- Subjects
DIABETES ,COVID-19 - Published
- 2020
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47. Frontline soldiers of globalisation: Port—city evolution and regional competition.
- Author
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Ducruet, César and Sung-Woo Lee
- Subjects
GLOBALIZATION ,PORT districts ,CITIES & towns ,SOCIAL change ,CITY dwellers ,ECONOMIC development ,INTERNATIONAL trade ,WORLD culture ,INTERNATIONAL markets - Abstract
This paper is an empirical attempt to measure the relative concentration of port-city functions in the context of globalisation. It reviews a number of urban and port issues regarding their complementary and contradictory aspects about the evolution of port cities. The main purpose is to verify how port function is more or less important to local economies, compared to other functions, through a temporal and global approach. Based on a matrix of port-city centrality and intermediacy, the main indicators available for international comparison are urban population and container throughput. An analysis of 653 places between 1970 and 2005 period is provided, using the relative concentration index (RCI) proposed by Vallega. The appropriate geographical scale to measure the relative evolution of port cities at a global level is discussed. Results tend to question previous models which consider functional and spatial separation between the city and its port as an ineluctable process. The port-city evolution appears to be gradual rather than linear or chaotic, and in many cases largely influenced by regional factors and local strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
48. Comparison of the Trauma Outcome between Urban and Suburban Hospital.
- Author
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Sung Hyuk Choi, Sung Woo Lee, Yun Sik Hong, Jung Min Jeon, and Su Jin Kim
- Abstract
This study compared the trauma outcome between urban and suburban hospitals. The medical records of patients admitted to the intensive care unit (ICU) following trauma, obtained from 1994 to 1995 and 2002 to 2003, were examined. One was a tertiary university teaching hospital with regional emergency medical center (EMC), and the other was a small general hospital in a suburban area. Since 1999, the suburban hospital has enlarged its capacities to include EMC. In this study, the standardizing W (Ws), 95% confidence interval (CI) of Ws, and the predicted survival rate (Ps) were calculated using the Trauma and Injury Severity Score (TRISS) method. From 1994 to 1995, 225 and 121 records of the urban and suburban hospital were reviewed, respectively. The performance of trauma care in the urban hospital was more accurate than that in the suburban (95% CI of the Ws in urban and small suburban hospital: –2.30 to 2.73 and –11.40 to –5.90, respectively). The actual survival rate of the suburban hospital was significantly lower than the predicted survival rate at all revised trauma score (RTS). From 2002 to 2003, 315 and 268 medical records of urban and suburban hospital were reviewed, respectively. The 95% CI of the Ws in urban and suburban hospital was –3.56 to 0.24 and –3.73 to 0.26, respectively. In addition, there were no differences in the distribution of actual survival rate that was compared with the predicted survival rate according to injury severity score (ISS) and RTS in each hospital. After increasing the capacity of the suburban hospital, the trauma care performance was more accurate, and the ability of the physiologic support had improved. In addition, a larger suburban hospital could manage more severely injured patients without the need for transfer (mean ISS from 1994–1995 to 2002–2003: 21.0 vs. 24.3, p = 0.059, mean RTS: 7.0 and 6.2, p = 0.003; transfer:admission ratio = 0.182:0.056, respectively, p = 0.01). In conclusion, under the well-constructed emergency medical service system, the enlargement of the capacities of emergency and intensive care should improve the performance of trauma care in suburban hospital. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
49. Increased Plasma Nitric Oxide Metabolites in Suicide Attempters.
- Author
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Bun-Hee Lee, Sung-Woo Lee, Dokyung Yoon, Heon-Jeong Lee, Jong-Chul Yang, Se-Hoon Shim, Do-Hoon Kim, Seung-Ho Ryu, Changsu Han, and Yong-Ku Kim
- Subjects
SUICIDAL behavior ,NITRIC oxide ,METABOLITES ,PATIENTS ,DEPRESSED persons - Abstract
Objective: To evaluate any correlation between plasma levels of nitric oxide metabolites (NO
x ) and suicide attempt. Method: Plasma NOx levels were measured in 53 patients who had recently attempted suicide, 58 nonsuicidal psychiatric patients, and 75 normal controls. The severity of suicidal behaviors was evaluated using Weisman and Worden’s Risk-Rescue Rating Scale. Results: Plasma NOx levels were significantly higher in suicidal patients than nonsuicidal psychiatric patients or normal control subjects (F = 11.029, d.f. = 2, 183, p < 0.001). Among the patients with a diagnosis of major depression, suicidal depressive patients had significantly higher plasma NOx levels than nonsuicidal depressive patients (t = –3.090, d.f. = 84, p = 0.003). Conclusion: Our study suggests that increased NO production in plasma is associated with suicide attempt, especially in depressive patients. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]- Published
- 2006
- Full Text
- View/download PDF
50. Explicit expression on specifications of mask mean to target and mask uniformity.
- Author
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Sung-Woo Lee, Doo-Youl Lee, Sang-Gyun Woo, and Han-Ku Cho
- Subjects
MASKS (Electronics) ,TECHNICAL specifications ,INDUSTRIAL design ,INDUSTRIAL engineering ,ENGINEERING design - Abstract
An analytic expression on the relationship of the mask mean to target (MTT) and the mask uniformity specifications is suggested. The MTT and uniformity (M-U) curve defines the boundary of the specification region, and this curve is explicitly expressed as mask error enhancement factors (MEEFs), dose sensitivities, and critical dimension (CD) tolerances of cell and peripheral patterns. This curve shows linear relationships between mask M-U. The decrease of the mask uniformity allows the increase of the mask MTT margin. M-U specifications are suggested for 63, 73, and 90 nm design rules. In this experiment, the tolerance of the cell pattern is given as the product of the MEEF and the mask uniformity margin which is specified as 60% of the total CD variation at the given design rule, while that of the peripheral pattern is set to be 10% of the design rule. An isolated pattern is selected as a peripheral pattern because its pitch size is infinite. The mask MTT specification for 63 nm is ±2.3 nm at the mask uniformity of 2.23 nm. For 73 nm design rule, specifications of mask MTT are ±1.94 and ±1.48 nm at the mask uniformities of 2.32 and 3.31 nm at the process constants (k1’s) of 0.295 and 0.322, respectively. For 90 nm design rule, the mask MTT specifications are ±3.89 and ±4.13 nm at mask uniformities of 3.89 and 4.13 nm for k1’s of 0.364 and 0.396, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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