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Breeding of ‘Skyblueball’, a New Gentiana spp. Cultivar with the Same Time Flower and Violet Blue Petals (연한 청색의 동시개화성 절화 용담 ‘스카이블루볼’ 육성)

  • Suh, Jong Taek;Yoo, Dong Lim;Kim, Su Jeong;Ryu, Seung Yeol;Nam, Chun Woo;Kwon, Young Seok;Jang, Suk Woo;Kim, Won Bae;Lee, Eung Ho;Choi, Chang Hak;Kim, Jeong Seon;Sung, Moon Seok
    • Korean Journal of Plant Resources
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    • v.29 no.5
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    • pp.630-633
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    • 2016
  • A new Gentiana spp. cultivar “Skyblueball” was bred by crossing between “Jinbu-65 line” with violet blue (VB 95B) colored petals as female and “Jinbu-1 line” with violet blue (VB 93B) petals as male in 2000 year. The superior line of 00-168-3 was selected in Daegwallyeong from 2001 to 2003 year, and its growth and flower characterization were conducted from 2004 to 2007 year in field of Daegwallyeong and Jinbu, Pyeongchang, Gangwon-do, Namwon, Jeollabuk-do and Jeju Special Self-Governing-do. The flower showed violet blue (VB 96C) color at opening, the petal of flower had not spot and flower stem color was purple. The flowers were bloomed at the same time from bottom to upside (Table 1). Plant height was 62.9 ㎝, number of flower stem per plant is 8.3, number of flower node per stem was 5.3, and number of flower per stem was 21.7 (Table 2). The flowering of ‘Skyblueball’ was bloomed from July 26 in Daegwallyeong, August 3 in Jinbu and Namwon, and June 28 in Jeju Special Self-Governing-do. ‘Skyblueball’ cultivar can be used for cut flower.

Medium Depths and Fixation Dates of 'Seolhyang' Strawberry Runner Plantlets in Nursery Field Influence the Seedling Quality and Early Growth after Transplanting (차근육묘를 위한 배지의 깊이 및 착근 시기가 '설향' 딸기 자묘 소질과 정식 후 초기 생장에 미치는 영향)

  • Park, Gab Soon;Choi, Jong Myung
    • Horticultural Science & Technology
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    • v.33 no.4
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    • pp.518-524
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    • 2015
  • The objective of this research was to investigate the influence of various depths of expanded rice hull (ERH) medium and fixation dates of runner plantlets of 'Seolhyang' strawberry on the growths in nursery field and in plastic house soil after transplanting. The five treatments in medium depths (30, 50, 70, 90, and 110 mm) and four treatments in fixation dates (1st and 15th July and 1st and 15th August) were tested. The growths of runner plantlets were investigated before transplanting to plastic house soil. The early growth and inflorescence rates of crops after transplant to plastic house soil were also investigated. The plant height and fresh weight of runner plantlets were the highest in the medium depths of 50, 70, and 90 mm. The medium depth of 30 mm had higher numbers of first roots, but lower root fresh weight compared to those of 70, 90, and 110 mm. The treatment of 30 mm in medium depth showed poorer growth in all indexes except root length and root weight compared to those of 70, 90, and 110 mm. The runner plantlets fixed on July 1 and July 15 showed good root growth and the weights of ERH adhered to form root balls were 18.3 g and 13.9 g, respectively. The detached amount of ERH was less than 40% in the two treatments when root balls were shaken by a vibratory sieve shaker. The plant growth at 45 days after transplanting to plastic house soil were not significantly different when the runner plantlets were fixed in the period from July 1 to Aug. 1. The inflorescence rates of the first cluster were 93 to 100% when runner plantlets were fixed in the period from July 1 to Aug. 1. By contrast the runner plantlets fixed on the Aug. 15 had a 67% in florescence rate for the first cluster. These results indicate that optimum depth of ERH medium was 7 cm and the ranges of optimum fixation dates are from July 20 to 25.

A STUDY ON IN VIVO AND IN VITRO AMALGAM CORROSION (아말감의 구강내 부식 및 인공 부식에 관한 연구)

  • Lim, Byong-Mok;Kwon, Hyuk-Choon;Um, Chung-Moon
    • Restorative Dentistry and Endodontics
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    • v.22 no.1
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    • pp.1-33
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    • 1997
  • The objective of this study was to analyze the in vitro and in vivo corrosion products of low and high copper amalgams. The four different types of amalgam alloy used in this study were Fine cut, Caulk spherical, Dispersalloy, and Tytin. After each amalgam alloy and Hg were triturated according to the directions of the manufacturer by means of the mechanical amalgamator(Amalgam mixer. Shinhung Co. Korea), the triturated mass was inserted into a cylindrical metal mold which was 12mm in diameter and 10mm in height. The mass was condensed by 150Kg/cm compressive force. The specimen was removed from the mold and aged at room temperature for about seven days. The standard surface preparation was routinely carried out by emery paper polishing under running water. In vitro amalgam specimens were potentiostatically polarized ten times in a normal saline solution at $37^{\circ}C$(potentiostat : HA-301. Hukuto Denko Corp. Japan). Each specimen was subjected to anodic polarization scan within the potential range -1700mV to+400mV(SCE). After corrosion tests, anodic polarization curves and corrosion potentials were obtained. The amount of component elements dissolved from amalgams into solution was measured three times by ICP AES(Inductive Coupled Plasma Atomic Emission Spectrometry: Plasma 40. Perkim Elmer Co. U.S.A.). The four different types of amalgam were filled in occlusal and buccal class I cavities of four human 3rd molars. After about five years the restorations were carefully removed after tooth extraction to preserve the structural details including the deteriorated margins. The occlusal surface, amalgam-tooth interface and the fractured surface of in vivo amalgam corrosion products were analyzed. In vivo and in vitro amalgam specimens were examined and analyzed metallographically by SEM(Scanning Electron Microscope: JSM 840. Jeol Co. Japan) and EDAX(Energy Dispersive Micro X-ray Analyser: JSM 840. Jeol Co. Japan). 1. The following results are obtained from in vitro corrosion tests. 1) Corrosion potentials of all amalgams became more noble after ten times passing through the in vitro corrosion test compared to first time. 2) After times through the test, released Cu concentration in saline solution was almost equal but highest in Fine cut. Ag and Hg ion concentration was highest in Caulk spherical and Sn was highest in Dispersalloy. 3) Analyses of surface corrosion products in vitro reveal the following results. a)The corroded surface of Caulk spherical has Na-Sn-Cl containing clusters of $5{\mu}m$ needle-like crystals and oval shapes of Sn-Cl phase, polyhedral Sn oxide phase. b)In Fine cut, there appeared to be a large Sn containing phase, surrounded by many Cu-Sn phases of $1{\mu}m$ granular shapes. c)Dispersalloy was covered by a thick reticular layer which contained Zn-Cl phase. d)In Tytin, a very thin, corroded layer had formed with irregularly growing Sn-Cl phases that looked like a stack of plates. 2. The following results are obtained by an analysis of in vivo amalgam corrosion products. 1) Occlusal surfaces of all amalgams were covered by thick amorphous layers containing Ca-P elements which were abraded by occlusal force. 2) In tooth-amalgam interface, Ca-P containing products were examined in all amalgams but were most clearly seen in low copper amalgams. 3) Sn oxide appeared as a polyhedral shape in internal space in Caulk spherical and Fine cut. 4) Apical pyramidal shaped Sn oxide and curved plate-like Sn-Cl phases resulted in Dispersalloy. 5) In Tytin, Sn oxide and Sn hydroxide were not seen but polyhedral Ag-Hg phase crystal appeared in internal space which assumed a ${\beta}_l$ phase.

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Site Characteristics and Vegetation Structure of the Habitat of Cauliflower Mushroom (Sparassis crispa) (꽃송이버섯 자생지의 입지특성 및 식생구조)

  • Oh, Deuk-Sil;Park, Joon-Moh;Park, Hyun;Ka, Kang-Hyeon;Chun, Woo-Jae
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.33-40
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    • 2009
  • From 2006 to 2008, natural habitat of Sparassis crispa were surveyed for investigating ecological conditions at sixteen different sites in Korea. The investigated sites showed very wide altitudinal distribution ranged from 240 meters to 1,100 meters above the sea level. In general, S. crispa showed distinct feature of heart-rot fungi as it occurs on soils around the stems of larch (Larix kaempferi) and Korean white pine (Pinus koraiensis). But it also could be found on stems or on the stumps of dead trees, which indicated that the fungus might have several invasion routes and capabilities to grow on various ecological conditions. All of the sixteen sites were pure stands consisted with conifers such as larch or Korean white pine. The dominant tree layer showed $15.3{\sim}38.0$ meters for tree heights, thicker than twenty centimeters for the diameter at breast height (DBH), and all of them were older than thirty years. Since the stands were pure stand, species diversity of trees in the sites was extremely low. While the dominant tree layer showed only pure coniferous stand, the co-dominant tree layer, shrub layer and herbaceous layer showed more diverse features with higher Shannon-Wiener (H') indices. Soil texture of thirteen sites among sixteen investigated sites were loamy soils, and the contents of organic matter in soil were more or less higher than general forest soils in Korea with $3.79{\sim}14.32%$. The cation exchange capacity (CEC) was also relatively higher than general forest soils with $16.1{\sim}27.2$ cmol+/kg. The data indicated that the cauliflower mushroom occurring sites were relatively fertile than general forest soils. The soils were acidic with pH ranged from 4.2 to 5.2, which were typical features for conifer stands in Korea.

Ecological Management of Sangnim Woods in Hamyang-gun, Korea by Analysis of Ecological Structure (함양 상림의 환경생태적 구조 분석 및 생태적 관리방안1)

  • 한봉호;김종엽;조현서
    • Korean Journal of Environment and Ecology
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    • v.17 no.4
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    • pp.324-336
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    • 2004
  • This study was achieved to present ecological administration plan by analyzing vegetation structure and condition rating class(environmental damage degree) of Sangnim Woods Natural Monument in Hamyang-gun, Korea. In vegetation structure part, actual vegetation was classified by 22 patterns and Quercus serrata Carpinus tschonoskii community(31.8%), Quercus serrata community(14.6%) ranged extensively. Main plant community was 8 types, and is fractionated by 13 plant communities according to stratigraphy development degree it is Quercus serrata community, Quercus serrata Carpinus tschonoskii community, Quercus aliena community, Quercus acutissima community, Carpinus tschonoskii community, Carpinus tschonoskii Quercus serrata community, Zelkova serrata-Quercus serrata community, and Planted area with korean landscape woody plants. Age of old growth trees that diameter of breast height over 38cm was 61∼77years. In condition rating class, area of class 3 was 51,960$m^2$(32.8%), area of class 4 was 6,583$m^2$(3.5%), and area of class 5 was 4,086$m^2$(2.6%) and gross area of class 3∼6 need artificial restoration was 61,619$m^2$(38.9%). Considering actual vegetation, plant community structure, and condition rating class biotope was classified by total 14 types. While distribution area of Queens spp. old growth forest of shrub damaged(51,246$m^2$, 32.4%) and deciduous broad leaved old growth forest of simple-layer structure(19,906$m^2$, 12.6%) is large and that of deciduous broad-leaved old growth forest of multi-layer structure(2,085$m^2$, 1.3%) and Queens spp. old growth forest of multi-layer structure may have to manage with user control by administration plan for stabilization of Sangnim Woods ecosystem for long-term. Also, both vegetation of shrub damaged and simple-layer structure as negative restoration area should be restored for ecological succession and both grassland and planted area with korean woody plants as positive restoration area should be revegetated by using ecological planting model of native vegetation structure in Sangnim Woods.

An Analysis of Growth Conditions of old Trees in Yangdong Villages (양동마을의 노거수 생육실태 분석)

  • Kim, Young-Hun;Deng, Bei-Jia;You, Ju-Han
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.2
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    • pp.95-107
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    • 2020
  • The purpose of this study is to provide the basic data by analyzing and analysing the Growth Conditions of old Trees in Yangdong village. This study investigated about the conducted on tree information, soil information, and tree health. The result are as follows. The trees information in Yangdong Village consists of Juniperus chinensis, Salix chaenomeloides, Salix pseudolasiogyne, Celtis sinensis, Zelkova serrata, Gleditsia japonica, and Gleditsia sinensis trees, The range of height was 4.0~17.0m, and the diameter was 0.51~1.34m, Juniperus chinensis trees of No.17 was most large. In the results of soil analysis, there showed that acidity was pH4.1~6.3, hardness of 5~48mm, organic matter content of 21.2~29.1g/kg, electrical conductivity(EC) of 0.34~1.76dS/m, available P2O5 of 79.8~451.6mg/kg, exchangeable K of 0.22~1.71cmol+/kg, exchangeable Ca of 4.98~7.44cmol+/kg, exchangeable Mg of 0.67~2.19cmol+/kg, exchangeable Na of 0.19~1.04cmol+/kg and cation exchange capacity(C.E.C) of 7.23~13.02cmol+/kg. As a result, the highest number of tree health levels is 8 of 11trees of Celtis sinensis, 2 of 7trees of Zelkova serrata, and 3 of Gleditsia sinensis, and 13 of 30 trees of health levels, The Older trees with high infection, spoil and hollowed part were the remaining trees except for the healthy part. Relatively, more than half of the number of targets is infected, decay, and the hollowed site, and it is necessary to perform surgery on the damaged area. In addition, preservation and protection measures should be implemented by supplying root nutrients for trees, controlling nutrients in the body to prevent secondary and tertiary damages that cause the infection site to metastasize to the health site, In order to continually monitor the trees, measures to improve the location environment and management of the trees should be sought.

A Nutrition Intakes Survey of Pregnant Women in a Urban Area -Application of Convenient Method for the Study of Nutritionial Status- (일개 도시지역 임신부의 영양섭취에 관한 조사연구 -간이식 영양조사법 이용-)

  • Kim, In-Sook
    • Journal of Preventive Medicine and Public Health
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    • v.16 no.1
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    • pp.99-104
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    • 1983
  • Aiming at the total 200 pregnant women including 150 ones registered with the Health Center of Chung Ku District and 50 ones registered with the Health Center of Mapo District, we have conducted a research study of the socio-medical characteristics, maternal child health, and the status of nutritional intake which has utilized the application of convenient method for the study of nutritional status, during the period of April 20 to May 25, 1983. And we have obtained the following conclusions: 1. Regarding age distribution, the pregnant women aged from 26 to 30 were most numerous, which was 54.0%. The percentage of women who experienced the first pregnancy was 12.0% and the percentage of those who experienced the second pregnancy was 37.0%, which was the highest. Regarding the weeks of pregnancy of the pregnant women, the first trimesterr was 11.5%, the second trimester 30.0%, and the third trimester 58.6%. 2. Regarding academic achievements, the pregnant women who graduated from middle schools reached 43.5%, which was the highest percentage. Regarding economic status, the pregnant women who owned their own houses were only 21.0%. And the pregnant women whose monthly income was from 300,000 won to 400,000 won were 40%, which was the most numerous. 5. The women above 15 years old who experienced the first menstruation were 84.0%. And those who experienced abortion were totally 54.4%. and 35.5% among those women experienced artificial abortion. 4. 70.5% of the pregnant women said that their health condition was excellent, 24.5% felt subjective complaints, and 5.0% specially received medical consultation for their diseases. 5. 82.0% received prenatal care, but 60.5% regularly received prenatal care. 68.0% received the education for nutrition and only 19.5% regularly received the education for nutrition. 6. Regarding the family composition, the families consisting of two generations were 47.0%, which was the most numerous. 97.5% of the preparation for meals was conducted by housewives. They said that they did not lack time for meal preparation. 7. 94.9% of the pregnant women said that they had eaten as in ordinary times during their pregnancy. 25.5% said that there were tabooed foods. Tabooed foods are chiefly pork, chicken, milk, and eggs. 68.0% don't drink milk during pregnancy, 32.5% take the intake of vitamins, and 20.5% take iron supplement. 8. The average amounts of the intake of protein, fat, and carbohydrate of a pregnant women are 49.3gm, 29.4gm, and 205.1gm respectively, which showed the phenomenon in which the amount of the intake of nutrition increased as the weeks of pregnancy increased. The average amount of the intake of salt was 14.2gm. 9. Regarding the hemoglobin value of all pregnant women, those whose hemoglobin value was less than 11.0gm were 66.5%, those whose hemoglobin value was 11 to 12 gm were 16.5%. and those whose hemoglobin value was above 12gm were 17.0%. The pregnant women whose hemoglobin value was less than 11.0gm in the first trimester of pregnancy, in the second trimester, and in the trimester were 81.8%, 62.8%, and 64.9% respectively. This shows that the phenomenon of anemia increased as the weeks of pregnancy increased 10. Regarding physical development of a pregnant woman during prenatal period, the height and weight were $156.7cm{\pm}14.1$ and $51.1kg{\pm}58$ respectively. When the standard increase of a prenatal weigt gain is set as 100%, the women over the range of 100% were 28.0% and the women under the range of 80% were 37.0%.

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A STUDY ON THE JUJEON OF AUTOMATIC CLEPSYDRA IN EARLY JOSEON DYNASTY (조선 전기 자동물시계의 주전(籌箭) 연구)

  • YUN, YONG-HYUN;KIM, SANG HYUK;MIHN, BYEONG-HEE;OH, KYONG TAEK
    • Publications of The Korean Astronomical Society
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    • v.36 no.3
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    • pp.65-78
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    • 2021
  • Jagyeokru, an automatic striking water clock described in the Sejong Sillok (Veritable Records of King Sejong) is essentially composed of a water quantity control device and a time-signal device, with the former controlling the amount or the flow rate of water and the latter automatically informing the time based on the former. What connects these two parts is a signal generating device or a power transmission device called the 'Jujeon' system, which includes a copper rod on the float and ball-racked scheduled plates. The copper products excavated under Gongpyeong-dong in Seoul include a lot of broken plate pieces and cylinder-like devices. If some plate pieces are put together, a large square plate with circular holes located in a zigzag can be completed, and at the upper right of it is carved 'the first scheduled plate (一箭).' Cylinder-like devices generally 3.8 cm in diameter are able to release a ball, and have a ginkgo leaf-like screen fixed on the inner axis and a bird-shaped hook of which the leg fixes another axis and the beak attaches to the leaf side. The lateral view of this cylinder-like device appears like a trapezoid and mounts an iron ball. The function of releasing a ball agrees with the description of Borugak Pavilion, where Jagyeokru was installed, written by Kim Don (1385 ~ 1440). The other accounts of Borugak Pavilion's and Heumgyeonggak Pavilion's water clocks describe these copper plates and ball releasing devices as the 'Jujeon' system. According to the description of Borugak Pavilion, a square wooden column has copper plates on the left and right sides the same height as the column, and the left copper plate has 12 drilled holes to keep the time of a 12 double-hours. Meanwhile, the right plate has 25 holes which represent seasonal night 5-hours (Kyeong) and their 5-subhours (Jeom), not 12 hours. There are 11 scheduled plates for seasonal night 5-hours made with copper, which are made to be attached or detached as the season. In accordance with Nujutongui (manual for the operation of the yardstick for the clepsydra), the first scheduled plate for the night is used from the winter solstice (冬至) to 2 days after Daehan (大寒), and from 4 days before Soseol (小雪) to a day before the winter solstice. Besides the first scheduled plate, we confirm discovering a third scheduled plate and a sixth scheduled plate among the excavated copper materials based on the spacing between holes. On the other hand, the width of the scheduled plate is different for these artifacts, measured as 144 mm compared to the description of the Borugak Pavilion, which is recorded as 51 mm. From this perspective, they may be the scheduled plates for the Heumgyeonggak Ongru made in 1438 (or 1554) or for the new Fortress Pavilion installed in Changdeokgung palace completed in 1536 (the 31st year of the reign of King Jungjong) in the early Joseon dynasty. This study presents the concept of the scheduled plates described in the literature, including their new operating mechanism. In addition, a detailed model of 11 scheduled plates is designed from the records and on the excavated relics. It is expected that this study will aid in efforts to restore and reconstruct the automatic water clocks of the early Joseon dynasty.

Distribution and Natural Regeneration of Abies holophylla in Plantations in Gapyeong, Gyeonggi-do (경기도 가평 지역 조림지 내 전나무(Abies holophylla)의 분포와 천연갱신)

  • Nam, Kwanghyun;Joo, Kwang Young;Choi, Eun Ho;Jung, Jong Bin;Park, Pil Sun
    • Journal of Korean Society of Forest Science
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    • v.110 no.3
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    • pp.341-354
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    • 2021
  • A large part of Gapyeong is occupied by Korean pine (Pinus koraiensis) and Japanese larch (Larix kaempferi) plantations. Abies holophylla stands are scattered throughout Gapyeong, but little information on their distribution is available. This study explored the potential of succession from planted species to native A. holophylla in plantations. Trees were inventoried and regeneration of A. holoplhylla and stand management history were examined in Korean pine, Japanese larch, and A. holophylla-dominated stands. The importance percentage of A. holophylla was the highest among species with a range of 36.1% to 79.1% in all stands and the density of A. holophylla in understory (DBH <2 cm or <1.3 m height) ranged from 50 to 5,820 trees ha-1. Non-metric multidimensional scaling classified stands into four types, AN, AP, AM, and P. The AN type showed a reverse J-shape DBH distribution, which was similar to that in natural A. holophylla stands. Both AP and AM types included Korean pine plantations with A. holophylla seed trees within stands. For AP, A. holophylla competed with planted species in overstory and deciduous broadleaved species in understory. The AM type was once thinned from below, thus stem density in the mid DBH classes was lower than upper or lower DBH classes. The P type consisted of plantations without A. holophylla seed trees. However, understory regeneration of A. holophylla was abundant through seed supply from A. holophylla in adjacent stands. Plantations with A. holophylla seed trees within or in adjacent stands showed vigorous natural regeneration of A. holophylla, highlighting the potential for succession from planted species to native A. holophylla in the Gapyeong area. Further studies can help develop techniques to restore plantations to native species-dominated natural stands using ecological succession.

Manufacturing Techniques of Bronze Seated Bodhisattva Statue of Goseongsa Temple in Gangjin (강진 고성사 청동보살좌상의 제작기술 연구)

  • LEE Seungchan;BAE Gowoon;CHUNG Kwangyong
    • Korean Journal of Heritage: History & Science
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    • v.57 no.1
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    • pp.146-159
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    • 2024
  • In this study, a study on the production technology of the Buddha statue and the production of raw material origin was conducted through scientific analysis on the Bronze seated Bodhisattva Statue of Goseongsa Temple, a treasure. As a result of microstructure analysis through a metal microscope, it was confirmed that the microstructure of the Bronze seated Bodhisattva Statue of Goseongsa Temple was a process-type dendritic structure, and the casting structure of bronze was well represented, so it was manufactured through casting. Subsequently, as a result of analyzing the alloy composition ratio through SEM-EDS, it was identified as a ternary alloy with 81.26 wt% of copper (Cu) and 16.42 wt% of tin (Sn) and 1.72 wt% of lead (Pb). The results of the analysis of lead isotope ratios using a thermal ionization mass spectrometer (TIMS) were substituted into the distribution of lead isotope ratios on the Korean Peninsula, it was shown in corresponding to Jeolla-do and Chungcheong-do regions and North and South Gyeongsang Province. This suggests that the raw materials used in their production were likely sourced from the mines around Goseong Temple in Gangjin. Despite the fact that the statue is a medium and large Buddha with a total height of 51 centimeters, 1.72 wt% of lead (Pb) was found as a result of alloy composition ratio analysis, which showed a similar composition to the lead content ratio of small bronze and gilt-bronze Buddha statues. Therefore, we compared and analyzed the results of the analysis of the composition ratio of the alloys of bronze and gilt bronze statues, which has been scientifically analyzed with a compositional age similar to that of the Bronze seated Bodhisattva Statue of Goseongsa Temple. Comparison results, Various factors, such as the size of the Buddha statue as well as its stylistic characteristics and the age of composition, may exist in determining the alloy composition ratio of the bronze and gilt bronze Buddha statues, and it was confirmed that the alloy composition ratio or casting technology was properly adjusted when the Buddha statue was created. In other words, it is judged that a more comprehensive system of Buddha statue production technology should be investigated by conducting archaeological and art history studies on stylistic characteristics and age of composition, as well as scientific analysis results such as observation of internal structure, microstructure observation, and analysis of alloy composition ratio using radiation transmission irradiation.