• Title/Summary/Keyword: Genesis

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Study on the Origin of Rapakivi Texture in Bangeojin Granite (방어진 화강암에 나타나는 라파키비 조직의 성인에 관한 연구)

  • 진미정;김종선;이준동
    • The Journal of the Petrological Society of Korea
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    • v.11 no.1
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    • pp.30-48
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    • 2002
  • Phenocrysts with rapakivi texture are easily observed in Bangeojin granite. The rapakivi texture is composed of inner pinkish alkali feldspars and white-colored mantling plagioclase. The Bangeojin granite distinctively includes lots of mafic microgranular enclaves and can be divided into five rock facies: (1) enclave-poor granite (EPG); (2) enclave-rich granite (ERG); (3) mafic microgranular enclave (MME); (4) hybrid zone between mafic microgranular enclave and granite (HZ); (5) hybrid zone-like enclaves (HLE). The rapakivi textures are observed in these five rock facies with no difference in shape and size. Plagioclase mantle commonly shows dendritic texture that is an important indicator to know the rapakivi genesis. The mantling texture would indicate supercooling condition during magma solidification process. In addition, mafic microgranular enclaves would imply the magma mingling environment. The magma mixing process had possibly caused the mantling texture. An abundance of rapakivi phenocrysts in HZ and the influxing phenomenon of the phenocrysts into MME support that there were physical chemical exchanges during the mingling. And this model of the magma mixing/mingling explain well the heterogeneous distribution of the rapakivi phenocrysts in the five rock facies. Therefore the rapakivi textures in the Bangeojin granite would have been formed by magma mixing process.

The genesis of Ulsan carbonate rocks: a possibility of carbonatite\ulcorner (울산 광산에 분포하는 탄산염암체의 성인에 관한 연구: 카보내타이트의 가능성)

  • 양경희;황진연;옥수석
    • The Journal of the Petrological Society of Korea
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    • v.10 no.1
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    • pp.1-12
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    • 2001
  • A small of carbonate rocks and spatially-associated ultramafic rocks uniquely occur in the ulsan iron-serpentine mine of the sourtheastern Kyungsang basin. The study of field geology, core drilling data and stable isotope analysis suggest that the carbonate rocks are carbonatite formed from the melt reflecting intrusive natures. Based on this study, the geology of the Ulsan iron-serpentinite mining area consists of Cretaceous sedimentary, volcanic, granitic ultramafic and carbonate rocks in ascending order. The carbonate and ultramafic rocks show concentric and ellipsoidal shapes at the outcrop and a funnel shape in the cross sectional view. Carbon and oxygen stable isotope analysis show a bimodal pattern rather than a typical mantle pattern, which may indicate that the melt was a secondary melt generated within the crus not in the mantle directly. The uprising of ultramafic melts would have melted lime-contained rocks forming a secondary carbonate melt in the upper crus. Then, the intrusion of the ultramafic melts would have melted lime-contained rocks forming a secondary carbonate melt in the upper crust. Then, the intrusion of the ultramafic melt was followed by the intrusion of the carbonate melt along deep-seated fractures. Well-developed major fractures in this area, fluid inclusion characteristics of the carbonate rocks, the spatial relation between the ultramafic and carbonate rocks and stable isotope data support interpreting the Ulsan carbonate rocks as carbonatite.

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Oogenesis in a Tubiculous Polychaete, Schizobranchia insignis Bush: I. Microscopic and Biometric Studies

  • Lee, Yang-Rim
    • The Korean Journal of Zoology
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    • v.20 no.2
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    • pp.77-92
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    • 1977
  • A study has been made to correlate morphological and biochemical differentiation in the oocytes of a tubiculous polychaete, Schizobranchia insignis. The pressent paper is concerned with an examination of the cytological changes during oogenesis and annual size distribution of oocytes, The oocytes are released from the ovary into the coelomic sac at the end of the oogonial division and grow to a maximum size (180 $\\mu$ diameter). Oogensis takes place continuously throughout a year, although the breeding season is the period between January and March. When the oocytes reach the largest size class, they remain constant in size thereafter and accumulate in the coelomic sac. The nucleolus, which first appears in the oocytes 5-10$\\mu$ diameter, grows in the early stages of oogenesis, becomes maximum in the oocytes 100-120$\\mu$ diameter, and is constant throughout the rest of the pertiod. The nuclelus initially has a single comartment but becomes bipartite prior to vitello genesis. Three types of yolk including lipid droplets, proteid granules and oval granules oof unknown composition form at different times of oogenesis. The lipid droplets and oval granules appear in the early stage, but mainly in the oocytes larger than 80 $\\mu$ diameter. Proteid yolk and cortical granules appear only in the oocytes larger than 80 $\\mu$ diameter Microvilli are abundant in the oocyte 80 $\\mu$ diameter and embedded in the vitelline membranc. In the oocytes 180 $\\mu$ diameter they have retracted from the vitelline membrane.

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Mineralization and Characterization of Boseung Kaolin in Gaya Area (가야 지역 보성 고령토의 광화작용 및 광물 특성)

  • Noh, Jin-Hwan
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.4
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    • pp.397-413
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    • 2008
  • In Gaya area, the Boseong kaolin deposits exhibit locally unusual occurrences such as downward enrichment of kaoin minerals, characteristic hydrothermal alterations (illite and stilbite), and phase relations among kaolin minerals in addition to the extensive weathering of anorthositic country rocks. This indicates that the kaolin deposits seem to be genetically formed as a mixed hydrothermal and residual model. The kaolin ores can be divided into five types on the basis of differences in occurrence, mineral composition and characters. These consist of two types of high-grade ores ranging above 80% in grade and low-grade ores as low as less than 80% including feldspar residuals or the peculiar impurity phase of illite-vermiculite-stilbite. Halloysite and kaolinite are mostly coexisted in the Boseong kaolin, and these kaolin minerals exhibit diverse appearances in crystallinity and morphology. Such a diversity in mineral phase and crystallinity seems to be originated from the complexity in genesis. In addition to these diverse characters of the kaolin, its applied-mineralogical characteristics such as chemical composition, thermal properties, whiteness, viscosity, and etc. made it disadvantageous in terms of ore quality.

Occurrence and Mineralogical Characteristics of Dolomite Ores from South Korea (국내 백운석 광석의 산상과 광물학적 특성)

  • Hwang, Jinyeon;Choi, Jin Beom;Jeong, Gi Young;Oh, Jiho;Choi, Younghun;Lee, Jinhyun
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.2
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    • pp.87-99
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    • 2013
  • The occurrence, mineralogical characteristics, and origin of the dolomite ores were investigated from major dolomite mines in South Korea. Mineralogical and textural properties of the ores and associated minerals were analyzed using X-ray diffraction, thin section petrography, and scanning electron microscopy. Dolomite ores were light to dark gray in color and mainly composed of dolomite in varying particle size with minor amounts of calcite, quartz and micas. Calcite, quartz, illite, feldspar, kaolin minerals, and chlorite occurred in local veins, dikes and alteration zones. Sepiolite and wollastonite occurred in the altered part of some mine. Asbestos minerals such as chrysotile and tremolite, however, were not identified in the present study. Reddish brown to yellow clay materials were mainly composed of illite, occasionally associated with kaolin minerals and smectite. These clay minerals might be a product of the local hydrothermal alteration related to the dyke intrusion and subsequent weathering. As well indicated in the previous studies, mineral composition, texture, and occurrence of the dolostone beds suggest their formation through the diagenesis of carbonate sediments deposited in the shallow sea during the Precambrian to Paleozoic period.

BIOLOGICAL STUDIES IN CHILD AND ADOLESCENT DEPRESSION (소아 ${\cdot}$ 청소년 우울장애의 생물학적 연구)

  • Cho, Soo-Churl
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.5 no.1
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    • pp.28-35
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    • 1994
  • Research on biological aspects on adult depression has been subjected to more than 25 years of systematic research, while biologic investigations regarding childhood and adolescent depression are only now being initiated. Although no unifying, explanatory theory of the biologic etiology of childhood depression emerges from the results of studies reviewed above, the findings do support that biological factors may be involved in the genesis of childhood depression. The research reviewed in this paper suggests that age and pubertal factors have major effects in most biological markers of depression. Some of these markers, like sleep EEG and neuroendocrine markers should be broken down by decades during adult life span. Thus, although adult data are very valuable points of departure for biological research on child and adolescent depression, it is very hard to transfer the adult data to prepubertal children and adolescents, ignoring the biological changes that take place in growth and development, pubety and aging. A great deal of work in basic developmental neuroscience remains to be done. It will be crucial for further advances in this field to determine the normal patterns of neurotransmitter interaction in this age group and to study children at high risk for depression. It will be also crucial to use primate models of depressive illness in order to be able to answer the many queations that cannot be investigated in humans for ethical issues. Conclusively, much closer collaboration between developmental and neurobiological and behavioral studies in primates and in humans will be essential for further development.

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A Study on The Fruits Mentioned in the Bible (성서에 언급된 과실에 관한 연구)

  • Kim, Sung-Mee;Lee, Kwang
    • Journal of the East Asian Society of Dietary Life
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    • v.9 no.2
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    • pp.149-160
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    • 1999
  • This paper is intended to find out what kinds of fruits are mentioned in the Bible and how they were used in those days. It has also analyzed in what terms they are expressed in the Korean Version of the Bible and studied agricultural regulations involved in the religion, and allegorical uses of the fruits. Olives were the primary fruit in the economy of the ancient times, followed by figs and vines. In addition, there are mentioned in the Bible almonds, apples, dates. mulberries and pomegranates. Olive trees have been grown for more than six thousand years. The Hebrew word. Zayit is mentioned in the Bible more than fifty times. Olive trees are not so beautiful in themselves but as they give us humans abundant reap and a lot of oil, they have been thought to be beautiful. Olive trees grow well on the seaside in the salty air and fog. Vines began to grown as early as in the Bronze Age(the period of 3000 to 2000 B.C.). In Northern Greece, grape seeds were found to belong to the year 4500 B.C. or so. The vine gardens produced raisins and wine as well as vines. Figs are the fruit which are first mentioned in the Bible(Genesis 3:7) and they were the precious product of the Palestine people, which is described in Deuteronomy 8:8. Figs are sweet and watery and can easily quench thirst on hot summer days. They were used for cookies and wine in the raw or dried state. An apple, which is tappuah in Hebrew, is mentioned as 'Sagwa' six times in the Revised Korean Version, and in the Korean Joint Version it is twice mentioned as 'Sagwa' and as 'Neungum' four times. In ASV and KJV, 'apple' appears eleven times. which is because' the apple of eye' is translated in the 'Nun-dong-ja(the pupil of the eye)'In the Korean Version. 'Sagwa(apple)'of Proverb 25:11, the Song of Songs 2:3, 2:5, 7:8, 8:5 and Joel 1 :12 have been thought to be doubtful. because apple trees cannot be grown in the areas mentioned in the Bible. Some maintain that the apples in the Bible refer to apricots(Prunus armeniaca, Citrus medica L.) or golden oranges (Citrus sinensis L. Obsbeck) which is confusing. In the Revised Korean Version, 'Salgu(apricots)' appears eight times while ASV and KJV translate almond into 'Salgu'. So since translating a genuine apricot into 'Salgu' can be confusing, a great care should be taken in the translation into Korean. Some hold that as some papyri arround the year 1200 B.C. describes pomegranate, apple, olive and fig trees growing on the Nile delta, tappuah rightly refers to 'Sagwa(apple)' In the Korean Joint Version, Sagwa and Neungum are used together to refer to the same fruit, which should be avoided. It is desirable to use the same word for the same thing. Sagwa' showing up six times In the HeL.Ised Korean Version should all be replaced by 'Neungum' Dates symbolized peace and abundance were used for food in the raw or dried state, and were made into honey. Pomegranates can be eaten in the raw state and be used for sherbets and wine. Juice made of promegranates can be mixed with wine and drunk.

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Monthly Gonadal and Sex Hormonal Changes of Indoor-Reared Seabass, Lateolabrax japonicus during Annual Reproductive Cycle (실내사육 농어, Lateolabrax japonicus의 생식소 및 성호르몬의 주년 변화)

  • Kang Duk Young;Han Hyoung Kyun;Baek Hea Ja
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.614-620
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    • 2002
  • The sea bass, Lateoiabrax japonicus is a highly valued fish in aquaculture in South Korea. For establishment of seedling production of sea bass,1 japonicus, we examined change of gonadal development and plasma steroid levels of sea bass reared in indoor tank. Male matured unsimultaneously faster than females and spawning of females took place between the end of January and March. After the spawning period, and until the following January, all the females were in preyitello genesis and in some males, spermatogenetic activity restarted gradually. In October, under reducing photoperiod, cortical alveoli appeared in growing oocyte and the development of spermatogenesis greatly increased. Between October and february, vitellogenesis and spermatogenesis occurred respectively in female and male and gonadosomatic index increased from 4.31 to $24.07\%$ in female and upper 6o/o in male. Also, two sex hormones were analyzed during the course of a reproductive cycle in the sea bass: plasma levels of the gonadal steroid testosterone (T) and estradiol-l7$\beta$ (E_{2}). Variation of the plasma concentrations of T and E, appeared to depend on gonad stages. Plasma T and E, levels were high from November to January, suggesting that an sufficient gonadal stimulation by both hormones may undergoing a processes for the formation of sperm and oocyte.

Effects of Carcass Processing Method and Curing Condition on Quality Characteristics of Ground Chicken Breasts (분쇄 계육 가슴살의 도체가공방법과 염지조건이 품질특성에 미치는 영향)

  • Choi, Ji-Hun;Kim, Il;Jeong, Jong-Youn;Lee, Eui-Soo;Choi, Yun-Sang;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.29 no.3
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    • pp.356-363
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    • 2009
  • This study was carried out to investigate the effect of hot boning and curing condition on the quality characteristics of ground chicken breast. Treatments were cured by four conditions follows; control (general curing method), T1 (after hot-boning and then immediately cured), T2 (after hot-boning and immediately cured, then frozen), and T3 (after hot-boning, immediately frozen, refrigerated and then cured). The pH of chicken breast in the state of pre-rigor was 6.22. The pH of cold storage or freezing chicken breast meat respectively were 5.70 or 5.61. The pH of T1 and T2 treatments were significantly higher than those of control and T3 treatment (p<0.05). After stored for 1 wk, the pH value of T1 treatment had a higher value than those of other treatments. T1 treatment had the highest water holding capacity and the lowest cooking loss among all treatments, regardless of the cooking methods. The reduction in diameter for T1 and T2 treatments was lower than those of control and T3 treatment (p<0.05). T1 treatment had the lowest fat loss and moisture loss among all treatments, and the emulsifying capacity of T1 treatment was the highest. The protein solubility of T1 treatment was significantly lower than that of T3 treatment.

Fluid Inclusion and Stable Isotope Studies of Mesothermal Gold Vein Deposits in Metamorphic Rocks of Central Sobaegsan Massif, Korea: Youngdong Area (소백산 육괴 중부 지역의 변성암에서 산출되는 중온형 금광상에 대한 유체 포유물 및 안정동위원소 연구. 영동지역)

  • Chip-Sup So
    • Economic and Environmental Geology
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    • v.32 no.6
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    • pp.561-573
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    • 1999
  • Mesothermal gold deposits of the Heungdeok, Daewon and Ilsaeng mines in the Youngdong area occur in fault shear zones in Precambrian metamorphic rocks of central Sobaegsan Massif, Korea, and formed in single stage of massive quartz veins (0.3 to 3 m thick). Ore mineralogy is simple, consisting dominantly of pyrrhotite, sphalerite and galena with subordinate pyrite, chalcopyrite, electrum, tetrahedrite and native bismuth. Fluid inclusion data indicate that hydrothermal mineralization occurred at high temperatures (>240$^{\circ}$ to 400$^{\circ}$C) from $H_{2}O-CO_{2}(-CH_{4})$-NaCI fluids with salinities less than 12 wt. % equiv. NaC!. Fluid inclusions in vein quartz comprise two main types. These are, in decreasing order of abundance, type I (aqueous liquid-rich) and type II (carbonic). Volumetric proportion of the carbonic phase in type II inclusions varies widely in a single quartz grain. Estimated $CH_4$ contents in the carbonic phase of type II inclusions are 2 to 20 mole %. Relationship between homogenization temperature and salinity of fluid inclusions suggests a complex history of fluid evolution, comprising the early fluid's unmixing accompanying $CO_2$ effervescence and later cooling. Estimated pressures of vein filling are at least 2 kbars. The ore mineralization formed from a magmatic fluid with the ${\delta}^{34}S_{{\Sigma}S}$, ${\delta}^{18}O_{water}$ and ${\delta}D_{water}$ values of -2.1 to 2.2$\textperthousand$, 4.7 to 9.3$\textperthousand$ and -63 to -79$\textperthousand$, respectively. This study validates the application of a magmatic model for the genesis of mesothermal gold deposits in Youngdong area.

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