• Title/Summary/Keyword: Pure sciences

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Neotectonic Crustal Deformation and Current Stress Field in the Korean Peninsula and Their Tectonic Implications: A Review (한반도 신기 지각변형과 현생 응력장 그리고 지구조적 의미: 논평)

  • Kim, Min-Cheol;Jung, Soohwan;Yoon, Sangwon;Jeong, Rae-Yoon;Song, Cheol Woo;Son, Moon
    • The Journal of the Petrological Society of Korea
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    • v.25 no.3
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    • pp.169-193
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    • 2016
  • In order to characterize the Neotectonic crustal deformation and current stress field in and around the Korean Peninsula and to interpret their tectonic implications, this paper synthetically analyzes the previous Quaternary fault and focal mechanism solution data and recent geotechnical in-situ stress data and examines the characteristics of crustal deformations and tectonic settings in and around East Asia after the Miocene. Most of the Quaternary fault outcrops in SE Korea occur along major inherited fault zones and show a NS-striking top-to-the-west thrust geometry, indicating that the faults were produced by local reactivation of appropriately oriented preexisting weaknesses under EW-trending pure compressional stress field. The focal mechanism solutions in and around the Korean Peninsula disclose that strike-slip faulting containing some reverse-slip component and reverse-slip faulting are significantly dominant on land and in sea area, respectively. The P-axes are horizontally clustered in ENE-WSW direction, whereas the T-axes are girdle-distributed in NNW direction. The geotechnical in-situ stress data in South Korea also indicate the ENE-trending maximum horizontal stress. The current crustal deformation in the Korean Peninsula is thus characterized by crustal contraction under regional ENE-WSW or E-W compression stress field. Based on the regional stress trajectories in and around East Asia, the current stress regime is interpreted to have resulted from the cooperation of westward shallow subduction of the Pacific Plate and collision of Indian and Eurasian continents, whereas the Philippine Sea plate have not a decisive effect on the stress-regime in the Korean Peninsula due to its high-angle subduction that resulted in dominant crust extension of the back-arc region. It is also interpreted that the Neotectonic crustal deformation and present-day tectonic setting of East Asia commenced with the change of the Pacific Plate motion during 5~3.2 Ma.

Mineral Phase Transitions of Jarosite Substituted by Oxyanions during the Reductive Dissolution Using Oxalate Solution (옥살레이트 용액을 이용한 환원성 용해 시 산화음이온으로 치환된 자로사이트의 광물 상변화)

  • Lee, Myoungsin;Lee, Dongho;Chun, Herin;Kim, Yeongkyoo;Baek, YoungDoo
    • Korean Journal of Mineralogy and Petrology
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    • v.34 no.2
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    • pp.95-106
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    • 2021
  • The SO4 in the jarosite structure can be substituted by other oxyanions, and therefore, the transition of jarosite to goethite plays a very important role in controlling the behavior of oxyanions. In this study, the phase change according to the species of the oxyanion in jarosite and the related behavior of the oxyanion was studied by mineralogical and geochemical methods when jarosite, which is coprecipitated with various oxynions, undergoes a phase change by a reductive dissolution. Jarosite substituted by five oxyanions by 5 mol% was used in this study. The mineral phase change induced by reductive dissolution using ammonium oxalate was investigated, and the order of phase transition rate of jarosite to goethite was MoO4-jarosite ≥ SeO4-jarosite ≥ CrO4-jarosite > pure jarosite > SeO3-jarosite > AsO4-jarosite, showing that the transition rates vary depending on the substituted oxyanion. The resultant concentration of the leached Fe was slightly different depending on the type of oxyanion and time but did not show a noticeable difference. The concentration of each oxyanion leached according to the change of the mineral phase showed that the order of concentration of oxyanions was Mo > Se(SeO3) > As > Se(SeO4) > Cr in general, and showed a slight increase with time. This trend was related to the species of oxyanions rather than mineral phase change. The results of this study showed that the phase transition of jarosite to goethite was affected by the species of oxyanions, but this tendency did not affect the concentrations leached oxyanions.

Host Specificity and Distribution of Putative Ectomycorrhizal Fungi in Pure Stands of Twelve Tree Species in Korea (한국(韓國) 12개(個) 수종(樹種) 임분내(林分內)의 외생균근(外生菌根) 버섯의 기주선택성(寄主選擇性)과 분석(分布)에 관(關)한 연구(硏究))

  • Lee, Kyung-Joon;Kim, Yang-Sup
    • The Korean Journal of Mycology
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    • v.15 no.1
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    • pp.48-69
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    • 1987
  • To understand host ranges and host specificity of ectomycorrhizal fungi and fungus specificity of host tree species, higher fungi from pure forest stands of following twelve tree species were collected for six years from 1981 to 1986: Pinus densiflora, P. rigida, P. koraiensis, Picea koraiensis, Larix leptolepis, Abies holophylla, Populus $alba{\times}glandulosa$, Castanea crenata, Quercus aliena, Q. acutissima, Q. mongolica, and Betula platyphylla. A total of 196 ectomycorrhizal species with 8 varieties in 48 genera were identified. Thirty-one species with one variety belonged to Russula, 22 species with 5 varieties to Amanita, 18 species with one variety to Lactarius. Fungi belonging to above three gepera, Laccaria, and Cantharellus had a relatively wide host range. Laccaria laccata was collected under all the 12 tree species, Amanita vaginata group under 11 tree species, Laccaria amethystina and Russula foetens under 10 tree species, Lactarius gerardii and Russula sororia under 9 tree species, and Amanita agglutinata, Cantharellus cibarius, Russula bella, and R. virescens under 8 tree species. Above 10 fungal species may be classified to have a wide host range. Following fungi were collected under 4 to 5 tree species of both conifers and broad-leaved trees: Amanita citrina, Boletus bicolor, B. erythropus, Lactarius piperatus, L. subzonar­ius, and Russula pseudodelica. Above fungi may be classified to have an intermediate host range. Chroogomphus, Gomphidius, Rhizopogon, and Suillus were collected only under Pinaceae and may be classified to have a narrow host range. Particularly Suillus grevillei was collected only under Larix leptolepis, and appeared to have high host specificity. A total of 83 ectomycorrhizal species were collected under Abies holophylla, 66 species under Pinus densiflora, 50 species under Pinus rigida, 49 species under Pinus koraiensis, 46 species under Quercus aliena, and 23 fungal species under Larix leptolepis. Particularly, Larix leptolepis was associated with different fungal flora, with fewer species of Amanita, Lactarius and Russula, and more species of Laccaria. Most host tree species surveyerl in the present study appeared to have low fungus specificity for ectomycorrhizal formation.

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Characteristics of Carcass and Meat Yields of Fattening Pigs by Production Step (비육돈 생산단계에 따른 도체 및 부분육 생산 특성)

  • Kim, J.H.;Park, B.Y.;Yoo, Y.M.;Cho, S.H.;Kim, Y.K.;Lee, J.M.;Yun, H.J.;Kim, K.N.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.793-800
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    • 2002
  • The characteristics of carcass and meat yields of fattening pigs by production steps were investigated with Landrace (LL, n=41), Yorkshire (YY, n=33), and Duroc (DD, n=30), $F_1$ (LY, n=25), the Crossbred of LYD (n=48). Duroc had more weight loss in carcasses weight than that of the other breed(p<0.05). Yorkshire and $F_1$ had higher production weight in retail cut than that of the other pure or crossbred. Carcass from Landrace and $F_1$ were significantly longer in length than the other breed(p<0.05). $F_1$ produced wider carcass than the other breed. Carcass thickness at aitch bone was higher for $F_1$ and Crossbred than the other breed(p<0.05). Landrace, Yorkshire and $F_1$ produced more loin and tenderloin in weight than the other breed (p<0.05). Yorkshire and $F_1$ produced more picnic shoulder when compared to the other breed. The hind legs produced from Yorkshire and $F_1$ were higher in weight and the fore legs produced from the Crossbred were higher in weight. Duroc produced the lowest weight of belly among the breeds. The acceptance level of loin were extremely low for all breed. Landrace had the highest acceptance level for tenderloin. Yorkshire had the highest acceptance level for picnic shoulder and ham when evaluated by export standard of Japan. In conclusion, The introduction of pure breed and establishment of mating steps are necessary to produce highly accepted pork with high acceptance in carcass and meat yields.

Comparison of Breeding Value by Establishment of Genomic Relationship Matrix in Pure Landrace Population (유전체 관계행렬 구성에 따른 Landrace 순종돈의 육종가 비교)

  • Lee, Joon-Ho;Cho, Kwang-Hyun;Cho, Chung-Il;Park, Kyung-Do;Lee, Deuk Hwan
    • Journal of Animal Science and Technology
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    • v.55 no.3
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    • pp.165-171
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    • 2013
  • Genomic relationship matrix (GRM) was constructed using whole genome SNP markers of swine and genomic breeding value was estimated by substitution of the numerator relationship matrix (NRM) based on pedigree information to GRM. Genotypes of 40,706 SNP markers from 448 pure Landrace pigs were used in this study and five kinds of GRM construction methods, G05, GMF, GOF, $GOF^*$ and GN, were compared with each other and with NRM. Coefficients of GOF considering each of observed allele frequencies showed the lowest deviation with coefficients of NRM and as coefficients of GMF considering the average minor allele frequency showed huge deviation from coefficients of NRM, movement of mean was expected by methods of allele frequency consideration. All GRM construction methods, except for $GOF^*$, showed normally distributed Mendelian sampling. As the result of breeding value (BV) estimation for days to 90 kg (D90KG) and average back-fat thickness (ABF) using NRM and GRM, correlation between BV of NRM and GRM was the highest by GOF and as genetic variance was overestimated by $GOF^*$, it was confirmed that scale of GRM is closely related with estimation of genetic variance. With the same amount of phenotype information, accuracy of BV based on genomic information was higher than BV based on pedigree information and these symptoms were more obvious for ABF then D90KG. Genetic evaluation of animal using relationship matrix by genomic information could be useful when there is lack of phenotype or relationship and prediction of BV for young animals without phenotype.

Characteristics and Distribution Pattern of Carbonate Rock Resources in Kangwon Area: The Middle Carboniferous Yobong Formation in the Northern Part of Yeongwoleup, Kangwon, Korea (강원 지역에 분포하는 석회석 자원의 특성과 부존환경: 영월읍 북부 지역의 중기 석탄기 요봉층을 중심으로)

  • Park, Soo-In;Lee, Hee-Kwon;Lee, Sang-Hun
    • Journal of the Korean earth science society
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    • v.21 no.5
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    • pp.583-594
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    • 2000
  • The Middle Carboniferous Yobong Formation with North-South trending is distributed in the Yeongheungri and Samokri of Yeongwoleup, Kangwon Province, Korea. A light gray thick and massive pure limestone is developed in the middle part of the Yobong Formation and it has been exploited for a long time. This study was carried out to investigate the lithological characteristics and geochemical compositions of the limestones and to figure out how geologic structures control the disribution of the limestones of the formation. The limestones of the Yobong formation are characterized by the fine and dense textures and the light gray to light brown in color. The limestones are composed of crinoid fragments, small foraminifers, fusulinids, gastropods, ostracods, etc. Based on the amount of grains and matrix, the Yobong Limestone can be classified as fine packstones and wackestones. The chemical analysis of limestones of the Yobong Formation was carried out to measure the contents of CaO, MgO, Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$. The content of CaO ranges from 48.12 to 59.31% and its average is about 54.52%. The average content of MgO is about 0.32% and the coutents of Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ are relatively low. The amounts of Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ of the limestones vary according to the kinds of limestone and their stratigraphical horizons in the formation. Generally, the CaO content of the limestones of the Yobong Formation decreases towards the top of the formation. Using geometric and structural analysis, we determined five progressively overprinted phases of deformation recorded in the study area. The anticline and syncline formed during the first and fourth deformation had controlled the distribution pattern of the Yobong Limestone of the Yobong Formation. The structures of deformation D$_1$ consist of F$_1$ isoclinal folds and foliations. The D$_2$ deformation had formed the isoclinal interstratal F$_2$ folds and axial plane cleavages which are locally developed within mudstones. The structural elements of deformation D$_3$ are axial plane cleavages associated with recumbent F$_3$ folds. These structures are overprinted by meso-scale and regional F$_4$ folds which are regionally dominant. Finally, the structures of D$_5$ consist of the thrust faults and folds associated with the thrust faults.

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Lack of Cytotoxicity of the Colorant in Conjugated Linoleic Acid against Human Cancer and Normal Cells (Conjugated linoleic acid 황갈색의 인체암세포와 인체정상세포에 대한 세포독성)

  • Ji, Yu-Chul;Ahn, Chae-Rin;Seo, Yang-Gon;Suh, Jeong-Se;Kim, Jeong-Ok;Ha, Yeong-Lae
    • Journal of Life Science
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    • v.22 no.8
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    • pp.1099-1106
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    • 2012
  • The cytotoxicity of the colorant in conjugated linoleic acid (CLA) was investigated in human cancer cell lines and a normal human cell line. Commercially-available CLA with a brown color (designate crude CLA; c-CLA) was distilled in a vacuum (10 mmHg-$220^{\circ}C$, 10 mmHg-$235^{\circ}C$, 10 mmHg-$240^{\circ}C$, and 20 mmHg-$260^{\circ}C$) for 30 min to obtain pure CLA (distilled CLA; d-CLA) and dark brown-colored CLA (residual CLA; r-CLA) samples. No color intensity was shown in the d-CLA sample obtained under 10 mmHg-$220^{\circ}C$ conditions of distillation when the L (brightness), a (red/blue), and b (yellow/green) parameters were analyzed, whereas the r-CLA sample showed a dark brown color. The composition of CLA isomers in both the d- and r-CLA samples, as compared to that of the c-CLA sample, was not significantly different when analyzed by gas chromatography. When the cytotoxicity of the r-CLA and d-CLA samples obtained under 10 mmHg-$220^{\circ}C$ conditions were compared against human breast cancer cells (MCF-7), human lung cancer cells (A-549), human colon cancer cells (HT-29), human prostate cancer cells (PC-3), and human neuroblastoma cells (SK-N-SH), no significant cytotoxicity was seen in the cell lines. These results suggest that the color or colorant in the CLA samples did not have any effects on the proliferation of human cancer and normal cells and imply that the colorant in commercially available CLA samples is safe for human consumption.

Air Sampling and Isotope Analyses of Water Vapor and CO2 using Multi-Level Profile System (다중연직농도시스템(Multi-Level Profile System)을 이용한 수증기와 이산화탄소 시료채취 및 안정동위원소 조성 분석)

  • Lee, Dong-Ho;Kim, Su-Jin;Cheon, Jung-Hwa;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.12 no.4
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    • pp.277-288
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    • 2010
  • The multi-level $H_2O/CO_2$ profile system has been widely used to quantify the storage and advection effects on energy and mass fluxes measured by eddy covariance systems. In this study, we expanded the utility of the profile system by accommodating air sampling devices for isotope analyses of water vapor and $CO_2$. A pre-evacuated 2L glass flask was connected to the discharge of an Infrared Gas Analyzer (IRGA) of the profile system so that airs with known concentration of $H_2O$ and $CO_2$ can be sampled. To test the performance of this sampling system, we sampled airs from 8 levels (from 0.1 to 40 m) at the KoFlux tower of Gwangneung deciduous forest, Korea. Air samples in the 2L flask were separated into its component gases and pure $H_2O$ and $CO_2$ were extracted by using a vacuum extraction line. This novel technique successfully produced vertical profiles of ${\delta}D$ of $H_2O$ and ${\delta}^{13}C$ of $CO_2$ in a mature forest, and estimated ${\delta}D$ of evapotranspiration (${\delta}D_{ET}$) and ${\delta}^{13}C$ of $CO_2$ from ecosystem respiration (${\delta}^{13}C_{resp}$) by using Keeling plots. While technical improvement is still required in various aspects, our sampling system has two major advantages over other proposed techniques. First, it is cost effective since our system uses the existing structure of the profile system. Second, both $CO_2$ and $H_2O$ can be sampled simultaneously so that net ecosystem exchange of $H_2O$ and $CO_2$ can be partitioned at the same temporal resolution, which will improve our understanding of the coupling between water and carbon cycles in terrestrial ecosystems.

A Study on the Moisturizing Effect and Preparation of Liquid Crystal Structures Using Sucrose Distearate Emulsifier (슈크로오스디스테아레이트를 사용한 액정구조의 생성과 보습효과에 관한 연구)

  • Kwak, Myeong-Heon;Kim, In-Young;Lee, Hwan-Myung;Park, Joo-Hoon
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.1
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    • pp.1-12
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    • 2016
  • This study is to make the liquid crystalline structure using sucrose distearate (Sucro-DS) emulsifier to create the hydrophilic type oil-in-water (O/W) emulsion, the droplets of the emulsion having a structure of a multi-lamellar structure. We have studied the physicochemical properties of Sucro-DS using those techniques. And it has been studied in the emulsion performance. In order to form the liquid crystalline structure applying 3 wt% of Sucro-DS, 5 wt% of glycerin, 5 wt% of squalane, 5 wt% of capric/caprylic triglyceride, 3wt% of cetostearyl alcohol, 1wt% of glyceryl mono-stearate, 78 wt% of pure water in mixture having the lamellar structure of stable multi-layer system was found to formed. By applying them, they were described how to create an unstable active material encapsulated cream. Further, the moisturizing cream was studied using this technique. It reported the results to the skin improvement effect by the human clinical trials. The pH range to produce a stable liquid crystal phase using a Sucro-DS was maintained in 5.2~7.5. In order to increase the stability of the liquid crystal, it was when behenyl alcohol containing 3 wt%, the hardness at this time was 13 kg/mm,min. Viscosity of the same amount was 25,000mPas/min. After a test for the effects of the emulsions, the concentration of 6 wt% Sucro-DS is that was appropriate, the particle size of the liquid crystal was 4~6mm. It was observed through a microscope analysis, reliability of the liquid crystal changes for 3 months was found to get stable at each $4^{\circ}C$, $25^{\circ}C$ and $45^{\circ}C$. In clinical trial test, before applying a moisturizing effect it was $13.4{\pm}7%$. Moisturizing cream liquid crystal was not formed in $14.5{\pm}5%$. Therefore, applying than ever before could see the moisture about 8.2% was improved. On the other hand, it was the moisturizing effect of the liquid cream is $19.2{\pm}7%$. The results showed that 43.3% improvement than that previously used. Applications fields, Sucro-DS emulsifier used liquid cream, lotion, eye cream and a variety of formulations can be developed, as well as the cosmetics industry is expected to be wide fields in the application of the external preparation for skin emulsion technology in the pharmaceutical industry and pharmaceutical industry.

Effects of Natural Product on the Inhibition of $5{\alpha}-Reductase$ Type 2 for the Development of Chemopreventive Agents in LNCaP Cells

  • Lee, Sung-Jin;Kim, Kyeong-Ho;Cho, Myung-Haing;Lee, Sang-Kook;Mar, Woong-Chon
    • Natural Product Sciences
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    • v.5 no.2
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    • pp.97-103
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    • 1999
  • The enzyme steroid $5{\alpha}-reductase$ is responsible for the conversion of testosterone into the most potent androgen dihydrotestosterone (DHT). In man, this steroid acts on a variety of androgen-responsive target tissues to mediate such diverse endocrine processes as male sexual differentiation in the fetus and prostatic growth in men. Androgen levels in the prostate may influence carcinogenesis in this organ. The use of a $5{\alpha}-reductase$ inhibitor, finasteride, in the chemoprevention of prostate cancer is being evaluated in a clinical trial and have been used successfully for treatment of benign prostatic hyperplasia. Therefore, for the discovery of $5{\alpha}-reductase$ type 2 inhibitors, we have evaluated the inhibitory effects of solvent fractionated extracts of natural products on $5{\alpha}-reductase$ type 2 activity. We have tested approximately 80 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from 100% methanol extracts of plants. The ethyl acetate fractions of Perilla sikokiana $(seed,\;IC_{50}\;:\;6.2\;ug/ml)$, Sophora flavescens $(root,\;IC_{50}\;:\;8.9\;ug/ml)$, and Angelica tenuissima $(root,\;IC_{50}\;:\;11.7\;ug/ml)$ revealed inhibitory effects on $5{\alpha}-reductase$ 2 activity in LNCaP cells. The effective ethyl acetate fractions of Perilla sikokiana, Sophora flavescens, Hydnocarpus anthelmintica, and Angelica tenuissima were subfractionated by column chromatography and tested. The subfractions $F4\;(IC_{50}\;:\;1.1\;ug/ml),\;F5\;(IC_{50}\;:\;2.0\;ug/ml),\;and\;F6\;(IC_{50}\;:\;5.8\;ug/ml)$ of the ethyl acetate fraction of Perilla sikokiana and the subfraction $F8\;(IC_{50}\;:\;5.3\;ug/ml)$ of the ethyl acetate fraction of Sophora flavescens displayed greater inhibition of $5{\alpha}-reductase$ type 2 than did finasteride in LNCaP cells. These active fractions are under the process of further sequential fractionation to find the effective pure compounds against $5{\alpha}-reductase$ 2 activity.

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