• Journal of the Korean earth science society
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• v.33 no.7
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• pp.618-626
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• 2012

The Cretaceous fossil sites of Seoyuri in Hwasun was designated as the Korean Natural Monument No. 487 in November 2007. It provides important resources for paleoenvironmental studies, including theropod trackways, plant fossils, mudcracks, ripple marks, and horizontal bedding. The Cretaceous sedimentary strata contain a wide variety of volcanic pebbles, 5-40 cm in diameter in the lower portion and are overlain by the Late Cretaceous Hwasun andesite. Whole rock absolute K-Ar age determinations were performed on six volcanic pebbles from the Cretaceous sedimentary strata and on two samples from the overlaying Hwasun andesite. These ages indicate that the rocks belong to the period between the Turonian of the late Cretaceous (91-70 Ma) and the Pliocene age of the early Cenozoic ($63.4{\pm}1.2$ and $62.1{\pm}1.2$ Ma). Thus, the K-Ar ages indicate that the maximum geological age of the dinosaur track-bearing sedimentary deposits is about ca. 70 Ma. Therefore, it suggests that the age is comparable to the formation ages of the dinosaur footprints-bearing deposits in Sado area of Yeosu (71-66Ma).

• Journal of Adhesion and Interface
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• v.11 no.3
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• pp.106-111
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• 2010

Na-MMT intercalated with PEGMA macromer was prepared using an EtAc/acetone mixture (1/1 by volume) as a solvent. PEGMA/(Na-MMT)-co-MMA/MA nanocomposites was synthesized by copolymerizing intercalated compound with MMA and MA, and then characterization was performed. The results of X-ray diffraction (XRD) showed that in the case of Na-MMT intercalated with PEGMA macromer the d-spacings of silicate of Na-MMT increased with increasing of Na-MMT loading. As the Na-MMT loading increases Tg showed increasing trend through the DSC measurement. TGA result showed that thermal stability of PEGMA/(Na-MMT)-co-MMA/MA nanocomposites improved a little more than the pure PEGMA-co-MMA/MA.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.1
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• pp.49-57
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• 2024

While arterial tone is generally determined by the phosphorylation of Ser¹⁹ in myosin light chain (p-MLC2), Thr¹⁸/Ser¹⁹ diphosphorylation of MLC2 (pp-MLC2) has been suggested to hinder the relaxation of smooth muscle. In a dual-wire myography of rodent pulmonary artery (PA) and mesenteric artery (MA), we noticed significantly slower relaxation in PA than in MA after 80 mM KCl-induced condition (80K-contraction). Thus, we investigated the MLC2 phosphorylation and the expression levels of its regulatory enzymes; soluble guanylate cyclase (sGC), Rho-A dependent kinase (ROCK) and myosin light chain phosphatase target regulatory subunit (MYPT1). Immunoblotting showed higher sGC-α and ROCK2 in PA than MA, while sGC-β and MYPT1 levels were higher in MA than in PA. Interestingly, the level of pp-MLC2 was higher in PA than in MA without stimulation. In the 80K-contraction state, the levels of p-MLC2 and pp-MLC2 were commonly increased. Treatment with the ROCK inhibitor (Y27632, 10 µM) reversed the higher pp-MLC2 in PA. In the myography study, pharmacological inhibition of sGC (ODQ, 10 µM) slowed relaxation during washout, which was more pronounced in PA than in MA. The simultaneous treatment of Y27632 and ODQ reversed the impaired relaxation in PA and MA. Although treatment of PA with Y27632 alone could increase the rate of relaxation, it was still slower than that of MA without Y27632 treatment. Taken together, we suggest that the higher ROCK and lower MYPT in PA would have induced the higher level of MLC2 phosphorylation, which is responsible for the characteristic slow relaxation in PA.

• Journal of the Korean earth science society
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• v.36 no.1
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• pp.27-35
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• 2015

This study aims to establish the age of the Cretaceous Togeum Formation in Gurye that reported the discovery of dinosaur eggshells and bones. This study also investigates to determine the period of the dinosaurs' dominance in the region. K-Ar ages are measured on the whole volcanic rocks in the lower - and upper parts of the formation. The six samples dated are volcanic pebbles deposited in the Geumjeongri Conglomerate that is distributed underneath the Togeum Formation, and the ages dated as Aptian ($118.3{\pm}2.3Ma$) or Albian ($103.6{\pm}2.0$, $102.5{\pm}2.0$, $99.9{\pm}1.9Ma$), which all correspond to the Early Cretaceous. In addition, the ages of andesites and porphyritic andesites overlying the Togeum Formation are dated in a similar way. The result is that the ages are apparently corresponding to the Campanian ($83.9{\pm}1.6$, $74.2{\pm}1.5$Ma) of the Late Cretaceous. Field evidence and the age results indicate that the formation of the Togeum and the activities of dinosaurs dated back between 84 and 100Ma. It suggests that the Togeum Formation be somewhat older than the Boseong Seonso Formation (81Ma) which contains egg shells, the Haenam Uhangni Formation (79-81 Ma) that has dinosaur, pterosaur and webbed bird footprints, and also older than the theropod egg nests (77-83Ma) found in the Aphaedo area.

• Proceedings of the KHMA Conference
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• 2013.11a
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• pp.225-225
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• 2013

• Korean Journal of Acupuncture
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• v.23 no.3
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• pp.81-98
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• 2006

Objectives : Acupuncture using a tonification or sedation techniques method is used as a controlling the medication for an early stroke in the Korean medicine. LR3 has indicatons of headache, vertigo, facial paralysis, apoplexy, epiepsy as the source acupoint of a liver meridian. So this study is aims to investigate the anti-apoptotic and neuroprotective effects of acupuncture on the focal ischemia induced by intraluminal filament insertion in rats. Methods : The focal ischemia was induced by intraluminal filament insertion into middle cerebral artery. The animals were divided into seven groups (n=8 in each group) : Normal, intactness group; Conrol group, no therapy group after being ischemia induced; MA-l, acupuncture perpendicularly without Tonification or Sedation techniques at LR3 after being ischemia induced; MA-2, acupuncture obliquely towards the knee at LR3 after being ischemia induced; MA-3, acupuncture obliquely towards the toe at LR3 after being ischemia induced; MA-4, acupuncture obliquely towards the knee and rotate 9 times in a clockwise direction at LR3 after being ischemia induced; MA-5, acupuncture obliquely towards the toe and rotate 6 times in a counterclockwise direction at LR3 after being ischemia induced. The anti-apoptotic and neuroprotective effects of Acupuncture techniques of tonification or sedation at LR3 are observed by mGluR5, Bax, Cresyl violet, ChAT-stain and NGF. Results : The intensity of mGluR5 and the density of ChAT was increased in MA-1 group. The intensity of Bax was decreased in MA-3, MA-4 group. The density of neurons stained by Cresyl violet and ChAT was increased in MA-2, MA-3, MA-4, MA-5 group. The density of neurons stained by NGF was only increased in MA-4 group. Conclusions : Our study suggests that acupuncture perpendicularly without Tonification or Sedation techniques and obliquely towards the knee and rotate 9 times in a clockwise direction(Tonifying technique) at LR3 after being ischemia induced at LR3 shows anti-apoptotic and neuroprotective effects on cholinergic neuron in focal cerebral ischemia of the stroke in rats.

• Resources Recycling
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• v.17 no.3
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• pp.29-34
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• 2008

Solvent extraction behaviors of iron(III) from chloride solution at high ionic strength condition between Alamine336 and TBP were compared by using MaCabe-Thiele diagram. Extraction isotherms of iron by the two extractants were obtained by calculating the equilibrium concentrations of iron in both phases from the initial extraction conditions. In calculating the equilibrium concentration of iron, chemical equilibria in the aqueous phase and mass balance together with the solvent extraction reaction were considered. MaCabe-Thiele diagram of iron by 1M Alamine336 indicated that two extraction stages could lead to complete extraction of 0.5M iron from 3M HCl solution at an A/O ratio of 6/5. The extraction power of 1M Alamine336 was found to be the same as 2-3M TBP. MaCabe-Thiele diagram together with the physical properties of the two extractants indicated that Alamine336 is superior to TBP in extracting ferric iron from chloride solution.

• Journal of Preventive Medicine and Public Health
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• v.37 no.3
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• pp.260-266
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• 2004

Objectives : To assess the impacts of implementing case payment system (CPS) to Medical Aid (MA) hemodialysis patients on the frequencies and expenditure of dialysis. Methods : Fifty-eight clinics and 35 tertiary care hospitals were identified as having a minimum of 10 hemodialysis patients for each of the MA and Medical Insurance (MI) programs, who received hemodialysis from the same dialysis facilities for both periods of July 2001 and July 2002. From these facilities, a total of 2,167 MA and 2,928 MI patients were identified as the study subjects. Using electronic claims data, the changes in the total number of monthly treatments and charges for outpatient hemodialysis treatments for each patient after the introduction of the CPS were compared between the MA and MI patients. Multiple regression analyses were performed to examine the independent impact of the CPS on the utilization and expenditure of dialysis treatments among the MA patients. Results : There was a significant decrease in the total charges for the hemodialysis treatments of the MA patients, 3.4% (p<0.05), whereas a significant increase was observed for the MI patients, 2.5% (p<0.05). For both the MA and MI patients, the frequency of the monthly hemodialysis treatments were significantly increased, 5.5 (from 12.1 to 12.7) and 7.8% (from 11.6 to 12.5), for the MA and MI patients, respectively. However, a multivariate regression analysis showed no significant difference in the changes in the total number of monthly hemodialysis treatments between the MA and MI patients after implementation of the CPS. Another regression model, regressing on the changes in the monthly claims of dialysis treatments, showed a significant negative coefficient for the MA ((=-70725, p<0.05). Conclusion : The significant decrease in the total charges for hemodialysis treatments among MA as compared to MI patients suggests that there was a cost reduction in the MA program following the introduction of the CPS.

• The Journal of the Petrological Society of Korea
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• v.1 no.1
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• pp.49-57
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• 1992

Whole rock and mineral ages for the Jecheon Granite distributed in the Ogcheon Fold Belt were dated by three radiometric methods, and its thermal history was elucidated as follows, on the basis of isotopic age data. Rb and Sr isotopic compositions of three whole rock and seven mineral concentrates made an isochron of 202.7${\pm}$ 1.9 Ma with a strontium initial ratio of 0.7140. Different age data of twelve mineral concentrates agree closely with the retention temperature of each mineral in K-Ar and Fission Track methods. The Jecheon granitic magma was generated by partial melting of crustal materials (S-type), or by mixins between mantle and crustal materials, intruded into the katazone or mesozone (7∼9 km) of the Ogcheon Fold Belt, at least in the Early Jurassic (about 203 Ma), and then crystallized and cooled down rapidly from about 600$^{\circ}C$ to 300$^{\circ}C$ (more than 20$^{\circ}C$/Ma), owing to thermal differences between the magma and the wall-rock. During the Middle to Late Jurassic (190∼140 Ma), the cooling of the granite was likely to stop and keep thermal equilibrium with the wall-rock. The severe tectonism associated with igneous activities and active weathering on the surface in Early to Late Cretaceous time (140∼70 Ma) might have accelerated the granite pluton to uplift rapidly (40∼60 m/Ma in average) up to 3∼4 km and cooled down from 300$^{\circ}C$ to 200$^{\circ}C$ (1.4 $^{\circ}C$/Ma). The granite pluton was likely to keep different uplifting and cooling rate of about 120 m/Ma and 5$^{\circ}C$/Ma in average from the Late Cretaceous to Early Tertiary (70∼50 Ma), and about 60 m/Ma and 2$^{\circ}C$/Ma in average from about 50 Ma up to the present, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.6
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• pp.946-954
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• 1995

The purpose of this study is to modify the hydrophobic property and dyeability of polyethylene terephthalate fiber. Methacrylic acid (2nA) was graftpolymerized with benzoyl peroxide (BPO) as initiator onto polyethylene terephthalate fabrics. The results were as follow; 1. Graft-polymerization exhibited maximum graft ratio at a temperature of 100"C. 2. The polymer was gradually grafted in great amount to the surface of MA-g-PET as graft ration increase; with the cross-section examination of MA-g-PET, it was discovered that graft-polymeriation had also taken place inside the textile core. 3. Dyes absorption of basic dyes and disperse dyes was improved as craft ratio increase; with resistance to laundering, the former showed grade 3-4 and the latter showed grade 5.de 5.