• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.207-213
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• 2009

This experiment was performed to understand the relationship between uptake of Fe and Mn by plants, red pepper and tomato, and soil physico-chemical properties under different soil conditions at an environmentally controlled chamber in NAAS(National Academy of Agricultural Science) in 2008. After the dipping for 3 days, four treatments, dipping, dipping+aeration, drainage, drainage+aeration, were set up to investigate the changes in soil redox potential and moisture content. Drainage+aeration changed soil to the oxidation condition from 72 hrs of treatment, and soil moisture content was immediately reduced after treatment. Uptake of Fe and Mn of red pepper was investigated with two treatments, soil only and the mixed[soil(50%) : bed soil(35%) : bark(15%)]. Red pepper leaves taken at 30 days after treatment absorbed excessively Mn from the treatment of soil only and the mixed, and thus uptake of iron was strongly reduced. Also, uptake pattern of Fe and Mn of tomato was examined with four treatment, soil only, soil(50%) + rice straw(50%), soil(50%) + compost(50%) and soil + aeration. Contents of Fe and Mn in tomato leaves was measured at 60 days after treatment. Fe content was the greatest in soil(50%) + compost(50%) whereas Mn content was the highest in soil only. As a result of this experiment, plant growth was stronger influenced by soil moisture content than redox potential or porosity, and the oxidation status of soil was likely to promote that plant predominantly absorbed Mn from soil and thus resulted in Fe deficiency.

• The Journal of the Petrological Society of Korea
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• v.14 no.2 s.40
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• pp.116-126
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• 2005

The Precambrian quartzite and calc-schist layers experienced multi-1310ing events are distributed along the two kinds of U-shaped 1310 (Fold I and II) with $N10^{\circ}E-directed$ fo1d axis in Wollong-myeon, Gwangtan-myeon, Jori-myeon of Paju city, the northeastern part of Gyeonggido. Occurrence of 10 layers of quartzite and 4 layers of calc-schist is not clear whether quartzite and schist layers were deposited sequentially each other or one to two layers of quartzite and schist were distributed repeatedly by isoclinal folding and thrusting, because of lack of sedimentary structures. In this paper, we tried to clarify the correlative relationship among the quartzite beds which are distributed along the U-shaped folds using geochemical tools such as rare earth element (REE) patterns and Nd isotope ratio. Quartzites have characteristics of LREE-flattened, HREE- slightly depleted patterns. They also show Ce negative anomaly whereas there are no Eu anomalies. As a result, quartzite beds occurred along the bilateral sides of fold axis show very similar REE patterns from outer side to inner side of 1314. The Nd model age of quartzite layers shows a trend that the inner part of fold is younger than the outer part of it. Such geochemical characteristics suggest that bilateral quartzite beds occurred along the fold axis were derived from the cogenetic source materials. The REE patterns and trace element geochemistry of mica schist intercalated within quartzite indicate that the quartzite and mica schist may be derived from different source materials. Our results suggest that REE and Nd isotope geochemistries may be very useful in clarifying the relationship of sedimentary deposits which do not show stratigraphical and structural connections in the field.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.235-247
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• 2012

Peridotite xenoliths hosted by alkali basalts from South Korea occur in Baengnyeong Island, Jeju Island, Boeun, Asan, Pyeongtaek and Ganseong areas. K-Ar whole-rock ages of the basaltic rocks range from 0.1 to 18.9 Ma. The peridotites are dominantly lherzolites and magnesian harzburgites, and the constituent minerals are Fo-rich olivine ($Fo_{88.4-92.0}$), En-rich orthopyroxene, Di-rich clinopyroxene, and Cr-rich spinel (Cr# = 7.8-53.6). Hydrous minerals, such as pargasite and phlogopite, or garnet have not been reported yet. The Korean peridotites are residues after variable degree of partial melting (up to 26%) and melt extraction from fertile MORB mantle. However, some samples (usually refractory harzburgites) exhibit metasomatic enrichment of the highly incompatible elements, such as LREE. Equilibration temperatures estimated using two-pyroxene geothermometry range from ca. 850 to $1050^{\circ}C$. Sr and Nd isotopic compositions in clinopyroxene separates from the Korean peridotites show trends between depleted MORB-like mantle (DMM) and bulk silicate earth (BSE), which can be explained by secondary metasomatic overprinting of a precursor time-integrated depleted mantle. The Korean peridotite clinopyroxenes define mixing trends between DMM and EM2 end members on Sr-Pb and Nd-Pb isotopic correlation diagrams, without any corresponding changes in the basement. This is contrary to what we observe in late Cenozoic intraplate volcanism in East Asia which shows two distinct mantle sources such as a DMM-EM1 array for NE China including Baengnyeong Island and a DMM-EM2 array for Southeast Asia including Jeju Island. This observation suggests the existence of large-scale two distinct mantle domains in the shallow asthenosphere beneath East Asia. The Re-Os model ages on Korean peridotites indicate that they have been isolated from convecting mantle between ca. 1.8 and 1.9 Ga.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.15 no.1
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• pp.91-100
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• 2004

Objectives：The effects of repeated maternal separation on the expression of glucocorticoid receptor (GR) and cyclooxygenase-2(COX-2) in the hippocampus of rat pups at preweanling stage were evaluated. Methods：The experimental, Repeated Maternal Separation group(N=4) was separated from the mother for four hours a day over a period of ten days beginning with postnatal day 4. The Control group(N=4), on the other hand, did not separated from the mother at all. GR and COX-2 expression in the hippocampus was examined by immunohistochemistry on postnatal day 14. Results：It was determined that the number of GR-immunopositive cells in the dentate gyrus of the hippocampus was significantly increased in the Repeated Maternal Separation group. The numbers of COX-2-immunopositive cells in the CA1 and CA3 were also significantly higher in the Repeated Maternal Separation group. Conclusion：These results suggest that maternal separation may be a significant developmental stress that induces GR and COX-2 expression in the hippocampus of developing pups.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.235-241
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• 2003

The effect of ultraviolet (UV) radiation on the characteristics of algae-derived dissolved organic matter (DOM) was examined by comparing the biodegradability and DOM fraction distribution of algal DOM before and after UV exposure. Algal DOM from two axenic cultures of Microcystis aeruginosa and Oscillatoria agardhii were irradiated for 24 h at a UV intensity of 42 W/$m^2$. A complete degradation of algal DOM during the UV exposure did not occur, remaining at constant concentrations of dissolved organic carbon(DOC). After UV exposure, however, microbial degradations were reduced by 17% in M. aeruginosa and 53% in O. agardhii, respectively, and decomposition rates also were two times lower in UV exposed algal DOM. In addition, the chemical compositions of algal DOM altered substantially after UV radiation exposure. The proportions of hydrophilic bases (HiB; protein-like DOM) decreased considerably in both algal DOM sources after UV exposure (16.8% and 20.0% of DOM, respectively), whereas those of hydrophilic acids (HiA; carboxylic acids-like DOM) increased as much as the decrease of the HiB fraction. Capillary ion electrophoresis (CE) analysis showed that several carboxylic acids increased significantly after UV exposure, further confirming an increase in HiA fractions. The results of this study clearly indicate that algal DOM can be changed in its chemical composition as well as biodegradability without complete degradation by UV radiation.

• The Journal of the Petrological Society of Korea
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• v.12 no.1
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• pp.16-31
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• 2003

The granites in the southern Gimcheon area can be divided into two parts, marginal hornblende biotite granodiorite (Mgd) and central biotite granodiorite to granite (Cgd). Mgd and Cgd are gray in color and display gradational contact relations and are mainly composed of coarse-grained and medium-grained rocks, respectively. Mgd has more frequent and larger mafic enclaves than Cgd, and the two granites partly show parallel foliation at thire contact with gneisses. From representative samples of the granites, K-Ar biotite ages of 197∼207 Ma were obtained. Considering the blocking temperature of biotite, it is suggested that the emplacement age of the granitic magma was probably late Triassic. The anorthite contents of plagioclases in Mgd display less variation than those of Cgd, indicating that Mgd crystallized within a narrow range of temperatures. In the Al$\_$total/-Mg diagram, the biotites from the granites plot within the subalkaline field, and the smooth slope indicates differentiation from a single magma. All amphiboles from the granites belong to magnesio-hornblende. The linear trends of major oxides, AFM and Ba-Sr-Rb indicate that Mgd and Cgd were fractionally differentiated from a single granitic magma body crystallizing from the margin inwards. The relations of modal (Qz+Af) vs. Op, K$_2$O vs. Na$_2$O, Fe$_2$ $O_3$ vs. FeO, Fe$\^$+3/(Fe$\^$+3/+Fe$\^$+2/) and K/Rb vs. Rb/Sr show that they belong to I-type and magnetite-series granitic rocks developed by the progressive melting products of fixed sources. REE data, normalized to chondrite value, have trends of enriched LREE and depleted HREE together with weakly negative Eu anomalies.

• Applied Microscopy
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• v.40 no.2
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• pp.89-99
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• 2010

Fibroblasts are the most common cells in connective tissue and are responsible for the synthesis of extracellular matrix components. The fibrosis associated with chronic inflammation and injury may contribute to cholangiocarcinoma pathogenesis, particularly through an increase in extracellular matrix components, which participate in the regulation of bile duct differentiation during development. Mitochondria produce ATP through oxidative metabolism to provide energy to the cell under physiological conditions. Also, mitochondrial dysfunction and oxidative stress have been implicated in cellular senescence and aging. Alternations in mitochondrial structure and function are early events of programmed cell death or apoptosis and mitochondria appear to be a central regulator of apoptosis in most somatic cell. Clonorchis sinensis, one of the most important parasite of the human bile duct in East Asia, arouses epithelial hyperplasia and ductal fibrosis. Isolated fibroblast from the bile ducts of rats infected by C. sinensis showed increase of cytoplasmic process. In addition, decrease of cellular proliferation was observed in fibroblasts which was isolated from normal rat bile duct and then cultured in media containing C. sinensis excretory-secretory product. However, the effects of C. sinensis infection on the mitochondrial enzyme distribution is not clearly reported yet. Therefore, we investigated the structural change of C. sinensis infected bile duct and mitochondrial enzyme distribution of the cultured fibroblast isolated from the C. sinensis infected rat bile duct. As a result, C. sinensis infected SD rat bile ducts showed the features of chronic clonorchiasis, such as ductal connective and epithelial tissue dilatation, or ductal fibrosis. In addition, fibroblast in ductal connective tissue was damaged by physical effect of fibrotic tissue and chemical stimulation. Immunohistochemically detected mitochondrial electron transferase (ATPase, COXII, Porin) was decreased in C. sinensis infected rat bile duct and cultured fibroblast from infected rat bile duct. It can be hypothesized that the reason why number of electron transferase decrease in fibroblast isolated from the rat bile duct infected with C. sinensis is because dysfunction of electron transport system is occurred mitochondrial dysfunction, increase of ROS (reactive oxygen species) and apoptosis after chemical damage on the cell caused by C. sinensis infection. Overall, C. sinensis infection induces fibrotic change of ductal connective tissue, mutation of cellular metabolism in fibroblast and mitochondrial dysfunction. Consequently, ductal fibrosis inhibits fibroblast proliferation and decreases mitochondrial electron transferase on fibroblast cytoplasm. It was assumed that the structure of bile duct could not normalized and ductal fibrosis was maintained for a long period of time according to fibroblast metamorphosis and death induced by mitochondrial dysfunction.

• Journal of Life Science
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• v.20 no.1
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• pp.90-96
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• 2010

Menopause increases the onset of hypertension and heart disease. Whereas it increases the blood LDL-cholesterol, triglyceride and total-cholesterol levels, the HDL-cholesterol concentration is reduced. Accordingly, we examined the effect of internal organs of Todarodes pacificus (IOT) on improvement in blood flow ability and changes in serum lipid content by using ovariectomized rats. For this study, the following four groups of 9-week-old Sprague-Dawley strain female rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (CON) and ovariectomized rats that were treated with IOT extracts. Ovary removal promoted platelet aggregability. However, IOT administration in the CON group after ovary excision resulted in a hinderance of coherence. The blood vessel passing time of ovariectomized rats was slower than the SHAM group. But the blood flow ability, which was slowed down for ovary removal, was improved by IOT administration. Serum triglyceride levels were significantly reduced by IOT administration. Moreover, blood HDL-cholesterol levels were reduced by ovary removal. However, IOT administration after ovary excision significantly increase HDL-cholesterol levels. The biological activity of IOT could be confirmed from these results. Moreover, IOT can be used in the development of functional foods which are meant to improve blood circulation and anti-platelet aggregation function. According to these results, we could know that IOT improved blood flow and anti-platelet aggregation. Therefore, it is expected that IOT can be used for the development of functional foods.

• The korean journal of orthodontics
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• v.27 no.4 s.63
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• pp.585-597
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• 1997

The purpose of this study was to evaluate the effect of estrogen on the periodontium and alveolar bone tissue response during experimental tooth movement in ovariectomized rats. Eighty female rats, 250gm in body weight, were classified into four groups ; sham operated group(NN), ovariectomized group(ON), ovariectomized & estrogen injected group(OE), sham operated & estrogen injected group(NE). flats were ovariectomized before 3 weeks to begin the experiment, which resulted in estrogen-deficient osteoporosis. In OE group & NE group, estrogen was injected $50{\mu}g/kg\;B.W.$ every other days. The left maxillary 1st molar was moved mesially with 60g force. Each foot rats were sacrificed after 1, 3, 7, 15 days from application of orthodontic appliance and alter additional 7 days from removal of orthodontic appliance. Histological findings on mesial roots of upper 1st molar in pressure and tension side are observed. The results were summarized as follows ; 1. In pressure side of alveolar bone, the number of osteoclasts and Howship's lacuna of ON group was significantly more than that of NN group from 1 day to 15 days(P<0.05). Especially the number of Howship's lacuna of ON group was significantly more than that of OE group during all experimental period(P<0.05). 2. In tension side of alveolar tune, the number of osteoclasts of ON group was significantly increased from 1 day to 3 days and decreased after 7 days. But the number of osteoclast of ON group was significantly mote than that of NN group during all experimental period(P<0.05). Also the number of Howship's lacuna of all groups was abruptly increased at 1 day, but slowly decreased till experimental 15 days. And the number of Howship's lacuna of of group was significantly more than that of NN group from 0 hr to 7 days(P<0.05). 3. The speed of tooth movement of OE group & NE group was similar to that of NN group(P>0.05). The amount of tooth movement of ON group between 7 days and 15 days was significantly greater than those of other groups(P<0.05). 4. The degree of relapse of ON group after 7 days from removal of orthodontic appliance was similar to those of other groups(P>0.05).

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.229-240
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• 2009

The high temperature and water content in soil profile probably affect the physiological disorder especially on cool-season turfgrasses in warm and humid weather of Korean summer. The purpose of this research was to analyze the effect of soil temperature and water content on the growth and stress response of creeping bentgrass(Agrostis palustris Huds.) under a humid and warm temperature. USGA(United State of Golf Association) green profile in laboratory test, Daily temperature changes were tested under a dried sand, 70% water content of field capacity, and saturated condition at $34^{\circ}C$ of the USGA green in lab. In this test, the dried sand reached to $80^{\circ}C$, however, the surface temperature decrease of $10^{\circ}C$ on the saturated condition. In the thermal properties test in field, thermal conductivity, thermal diffusivity, and soil temperature were increased followed by irrigation practise. In the water-deficient condition, the highest soil temperature was reached temporally right after irrigation, however, the excessive soil water content higher than field water holding capacity showed the highest soil temperature after a while. This result indicated that a heat damage to root system was caused from the thermal conductivity of a high surface soil temperature. The excessive irrigation when a high turf surface temperature should occur a negative result on tufgrass growth, moreover, it would be fatal to root growth of creeping bentgrass, especially when associated with a poor draining system on USGA sand green. Overall, this study shows that high soil temperature with water-excessive condition negatively affects on cool-season grass during the summer season, suggesting that excessive irrigation, over 70% field capacity of soil condition, does not help to reduce soil temperature for summer season in Korea. In the study that cool-season grass were treated with different water content of soil, The soil had higher temperature and more water holding capacity when treatment rate of soil conditioner was increased. The best growth at the normal water condition and the worst state of growth at thee water-excessive condition were observed.