• Journal of Korean Society of Transportation
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• v.11 no.1
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• pp.5-22
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• 1993

This study examines the 1980 Census and the 1987 Travel Survey data sets, in order to identify commuting trends in the Seoul Metropolitan Area. The commuting field of Seoul includes the cities and counties contiguous to Seoul, as well as Inchon, Suwon and Ansan City and Paju County. The study finds little support for the expansion of the commuting field toward distant counties of Kyonggi Province; instead an intensification of commuting within the field is more salient. The most prominent trend, within the city limit of Seoul, is that journey-to-work toward the city center has decreased whereas peripheral journeys increased considerably. The work trips have increased most in the southwestern sector of the city; a moderate increase in the northeastern and southwestern sectors; and decreases in the center and the northwestern sector of the city. Factorial analyses of the work trip data also reveal the emergence of sub-regions of journey-to-work in the peripheries of the city. Such a spatial pattern of commuting changes resemble that of population changes, and correspond in part to the layout of the subway system.

• Journal of Korean Neurosurgical Society
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• v.61 no.1
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• pp.75-80
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• 2018

Objective : Among the various sacropelvic fixation methods, S2 alar-iliac (S2AI) screw fixation has several advantages compared to conventional iliac wing screw. However, the placement of S2AI screw still remains a challenge. The purpose of this study was to describe a novel technique of free hand S2AI screw insertion using a K-wire and cannulated screw, and to evaluate the accuracy of the technique. Methods : S2AI screw was inserted by free hand technique in sixteen consecutive patients without any fluoroscopic guidance. The gearshift was advanced to make a pilot hole passing through the sacroiliac joint and directing the anterior inferior iliac spine. A K-wire was placed through the pilot hole. After introducing a cannulated tapper along with the K-wire, a cannulated S2AI screw was installed over the K-wire. Results : Thirty-three S2AI screws were placed in sixteen consecutive patients. Thirty-two screws were cannulated screws, and one screw was a conventional non-cannulated screw. Thirty out of 32 (93.8%) cannulated screws were accurately positioned, whereas two cannulated screws and one non-cannulated screw violated lateral cortex of the ilium. Conclusion : The technique using K-wire and cannulated screw can provide accurate placement of free hand S2AI screw.

• Journal of Korean Neurosurgical Society
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• v.55 no.4
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• pp.226-229
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• 2014

We describe a rare case of intradural-extramedullary primary spinal cysticercosis. A 42-year-old man visited our institute for lower back pain. He denied having consumed raw meet. Magnetic resonance (MR) images revealed an intradural pure cystic mass at the L3-L4 level. A radiologic diagnosis of spinal arachnoid cyst was established. Three years later, he complained of aggravated back pain, and follow-up MR examination showed a markedly expanded cyst, occupying the subarachnoid space from the T11 to the S1 level. L2 hemilaminectomy was performed, and a yellowish infected cyst bulged out through the dural opening. The cyst was removed en bloc. The histopathological findings of the cyst were consistent with parasitic infection. Serum enzyme-linked immunosorbent assay (ELISA) confirmed the presence of spinal cysticercosis. As there was no intracranial lesion, the final diagnosis was primary spinal cysticercosis, which is very rare. MR imaging is a sensitive diagnostic tool for detecting cystic lesions in the spine; however, it is difficult to distinguish cysticercosis from non-infectious cysts such as an arachnoid cyst without using gadolinium enhancement. Clinicians treating spinal cysts with an unusual clinical course should include cysticercosis as a differential diagnosis. We recommend contrast-enhanced MR imaging and serum ELISA in the diagnostic work-up of such cases.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.114-124
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• 2011

The characteristics of pesticide residues by multiresidue analysis method using GC, HPLC and GC-MSD were examined for 18,069 numbers of 91 kinds of vegetables in Seoul from 2007 to 2009. Detection rates of pesticide residues were 11.2% in 2007, 8.5% in 2008 and 12.0% in 2009, respectively, and the excess rates of Maximum Residue Limits (MRLs) showed a declining tendency as 4.6% in 2007, 2.8% in 2008 and 2.1% in 2009, respectively. The pesticides exceeding MRLs were 43 ingredients in 2007, 30 ingredients in 2008 and 36 ingredients in 2009, respectively. The frequencies of pesticides exceeding MRLs were 71 of azoxystrobin in 2007, 29 of procymidone in 2008, 24 of endosulfan in 2009, respectively. The excess rate of mustard green for MRLs in comparison with sample numbers was the highest among vegetables analyzed more than 10 cases each year. As a result of comparing annually pesticide residues about pesticide ingredients showed high frequency rates for pesticide detection, there was a statistical significance for the detection quantities of diazinon, endosulfan, paclobutrazol and procymidone.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.294-300
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• 2012

Capsaicinoids are responsible for the pungency of Capsicum species. Among the several reported methods for quantifying capsaicinoids in pepper, liquid chromatography methods such as TLC and HPLC have been the most widely used due to their precision and reliability. However, they are quite expensive and time consuming to be applied to the field breeding. In this paper, we demonstrated that Gibb's reagent, 2,6-dichloroquinone chlorimide, mediated measurement of capsaicinoids is a simple and reliable method for determining the presence/absence of capsaicinoids, and estimating the amount of capsacinoids in pepper fruits. The capsaicinoids could be also detected via colorimetiric reactions of the Gibb's reagent. This simple method has been verified to be as accurate as the HPLC analysis. We have also modified this method for a high through-put analysis. This method will be useful for measuring capsaicinids in pungency breeding programs in pepper.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.293-299
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• 2012

The residual contents of fluoroquinolones in fish and shrimp were analyzed by using HPLC-FLD and LC-MS. The limit of detection (LOD) and limit of quantification (LOQ) for fluoroquinolones by HPLC-FLD were 0.0030-0.0083 and 0.0090-0.0252 mg/kg, respectively. Those by LC-MS were 0.0019-0.0040 and 0.0059-0.0122 mg/kg, respectively. Recoveries regarding ofloxacin, norfloxacin, pefloxacin, ciprofloxacin and enrofloxacin ranged from 76.4-104.6%. The detection rate of fluoroquinolones was 7.5% from a total of 268 samples. In only one Korean bullhead sample, the sum of ciprofloxacin and enrofloxacin contents was detected at a higher level than its maximum residue limits (MRL) of 0.1 mg/kg. Ofloxacin, norfloxacin and pefloxacin were not detected in any samples and detection rates of ciprofloxacin and enrofloxacin were 3.4% and 6.7%, respectively. In detection rate by species eel (2.6%), loach (2.2%), Korean bullhead (1.5%), carp (0.7%) and snakehead (0.4%) were in order.

• Proceedings of the Optical Society of Korea Conference
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• 1995.06a
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• pp.127-137
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• 1995

Anomalously large real space charge transfer through thick barries in GaAs asymmetric double quantum wells is studied by photoluminesence exitation. This inter-well excitonic transfer is very large when the barrier is the Al0.3Ga0.7As alloy, but disappears when the barrier is GaAs/AlAs digital alloy with an equivalent Al concentration of 0.28. These resilts combined with observed x and barrier thickness depence suggest that the spatial fluctuation of the atomic arrangment of Ga and Al in the alloy may be responsible for this transfer. This picture is supported by the quantum mechanical calculation in three dimensions which takes into account the side fluctuation effects.

• Journal of Chest Surgery
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• v.55 no.5
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• pp.361-363
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• 2022

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.923-929
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• 2016

The purpose of this study was to evaluate the protective effect of $PineXol^{(R)}$ on $H_2O_2$-induced cell death in SK-N-MC cells, and in early stage focal ischemia rodent model. SK-N-MC cells were pre-treated with $200{\mu}M$ $H_2O_2$ or various concentrations of $PineXol^{(R)}$ (10, 30, and 50 pg/mL) for 24 h, and then exposed to $H_2O_2$ for 3 h. Cell death was assessed by the CCK-8 assay, reactive oxygen species (ROS) assay, and lactate and dehydrogenase (LDH) release assay. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) expressions were also analyzed by western blotting. Focal ischemia rodent model was used as the in vivo model, and different concentrations of $PineXol^{(R)}$ (1, 10, and 100 mg/kg) were administered. One week after administration, reduction of infarct volume was analyzed by TTC staining. Cell viability of $H_2O_2$-treated SK-N-MC cells significantly increased by pre-treatment of $PineXol^{(R)}$ (p<0.05). $PineXol^{(R)}$ pre-treatment also induced significant decrease of ROS and LDH expressions. However, $PineXol^{(R)}$ did not affect the infarct volume. These results suggest that $PineXol^{(R)}$ has significant neuroprotective effect in vitro, but statistical significance was not confirmed in the in vivo focal ischemia model.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.45-51
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• 2011

A low acid phosphatase 3 (lap3) mutant was identified and characterized from an Arabidopsis activation-tagged (Weigel) population. The roots of the lap3 plants showed lower acid phosphatase (APase) activity compared to wild-type ones under low-Pi conditions ($10{\mu}M\;Pi$). Plasmid rescue experiments revealed that the activation-tagging vector was inserted into the intergenic region between At4g31540 and At4g31550 in the Arabidopsis genome. The genotypic segregation of the lap3 mutation was tightly linked with the phenotypic segregation of root APase activity in the prgeny of lap3. The transcript level of the At4g31520 (SDA1: SEVERE DEPOLYMERIZATION OF ACTIN 1), located 7.4 kb from the CaMV 35S enhancers in the lap3 mutant, was significantly reduced compared to that in the wild type. It was speculated that cellular actin polymerization may be involved in Pi acquisition in higher plants.