• Title/Summary/Keyword: 한후기

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Role of Wetland Plants as Oxygen and Water Pump into Benthic Sediments (퇴적물내의 산소와 물 수송에 관한 습지 식물의 역할)

  • Choi, Jung-Hyun;Park, Seok-Soon
    • Korean Journal of Ecology and Environment
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    • v.37 no.4 s.109
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    • pp.436-447
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    • 2004
  • Wetland plants have evolved specialized adaptations to survive in the low-oxygen conditions associated with prolonged flooding. The development of internal gas space by means of aerenchyma is crucial for wetland plants to transport $O_2$ from the atmosphere into the roots and rhizome. The formation of tissue with high porosity depends on the species and environmental condition, which can control the depth of root penetration and the duration of root tolerance in the flooded sediments. The oxygen in the internal gas space of plants can be delivered from the atmosphere to the root and rhizome by both passive molecular diffusion and convective throughflow. The release of $O_2$ from the roots supplies oxygen demand for root respiration, microbial respiration, and chemical oxidation processes and stimulates aerobic decomposition of organic matter. Another essential mechanism of wetland plants is downward water movement across the root zone induced by water uptake. Natural and constructed wetlands sediments have low hydraulic conductivity due to the relatively fine particle sizes in the litter layer and, therefore, negligible water movement. Under such condition, the water uptake by wetland plants creates a water potential difference in the rhizosphere which acts as a driving force to draw water and dissolved solutes into the sediments. A large number of anatomical, morphological and physiological studies have been conducted to investigate the specialized adaptations of wetland plants that enable them to tolerate water saturated environment and to support their biochemical activities. Despite this, there is little knowledge regarding how the combined effects of wetland plants influence the biogeochemistry of wetland sediments. A further investigation of how the Presence of plants and their growth cycle affects the biogeochemistry of sediments will be of particular importance to understand the role of wetland in the ecological environment.

Spawning Behavior and Early Life History of Grass Puffer, Takifugu niphobles (Jordan et Snyder) (Teleostei: Tetraodontidae) (복섬, Takifugu niphobles(Jordan et Snyder)의 산란습성(産卵習性) 및 초기생활사(初期生活史))

  • Oh, Sung-Hyun;Han, Kyeong-Ho;Kim, Yong-Min;Joung, Hyun-Ho;Shin, Sang-Soo;Kim, Yong-Uk
    • Korean Journal of Ichthyology
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    • v.12 no.4
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    • pp.236-243
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    • 2000
  • The purpose of present the study was to describe the spawning behavior and early life history of the grass puffer, Takifugu niphobles. The grass puffer was caught at the spawning ground on the coast Dolsan, Korea from May to the 1998. Artificial fertilization was carried out to get fertilied eggs. Spawning season was from the end of May to the beginning of July on the coast of the Dolsan, Korea. Form 2~6 days before the spring tide the aduct males and females began to aggregate in the shore water, and they spawned in the upper part of intertidal zone exposed to air among pebble stone. The fertilized eggs were demersal, transparent and spherical in shape, and its diameter were 0.87~0.95 mm with several oil globules of 0.0014~0.0540 mm. Hatching began about 146 hours after fertilization under water temperature $21.2{\sim}22.3^{\circ}C$. The newly-hatched larva was 2.02~2.24 mm in total length (TL, mean: 2.14 mm), with 22~24(8~9+14~15) myotomes, and mouth and anus was not yet open. In 3 days after hatching it was measured 2.64~2.93 mm in TL (mean: 2.76 mm), and yolk sac was completely absorbed and transformed to postlarval stage. In 15 days after hatching it was measured 4.43~4.82mm in TL (mean: 4.59mm), and the caudal notochord flexion started. The larvae reached the juvenile stage in 28 days after hatching and attained 7.55~7.65mm in TL (mean: 7.60mm), and all fin-rays were formed.

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Effects of Dietary Supplementation of Coffee Meal on Intestinal Enzyme Activity, Biochemical Profiles and Microbial Population in Broiler Chicks (커피박 첨가가 육계의 소장 효소 활성도, 생화학 지표 및 장내 미생물 균총에 미치는 영향)

  • Ko, Young-Hyun;Yun, Seo-Hyun;Song, Min-Hae;Kim, Se-Yun;Kim, Jong-Sun;Kim, Hyoun-Wook;Jang, In-Surk
    • Korean Journal of Poultry Science
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    • v.41 no.2
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    • pp.105-113
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    • 2014
  • The current study was performed to investigate the effects of dietary supplementation of dried coffee meal (CM) on growth performance, intestinal and blood biochemical index, intestinal enzymes, and cecal microbial populations. A total of 162, 3-day-old male broiler chicks were randomly allocated into three dietary groups: control group (CON), basal diet added with 0.5% CM (CM I), and basal diet added with 1.0% CM (CM II). Dietary supplementation of CM did not change bird performance and the relative weight of intestinal mucosal tissues. The birds fed the diet supplemented with CM (0.5 and 1.0%) significantly decreased mucosal glucose concentration (P<0.05) without affecting blood glucose level compared with those fed control diet. The level of blood aspartate aminotransferase (AST) significantly increased in CM II group (P<0.05) without affecting ${\gamma}$-glutamyl transpeptidase (${\gamma}$-GTP) compared with that in the CON group. The specific activity of intestinal maltase, leucine aminopeptidase (LAP) and alkaline phosphatase (ALP) were not affected by dietary supplementation of CM, whereas sucrase activity in birds fed the diet supplemented with CM was decreased (P<0.05) compared to that in the control birds. The colony forming units (CFU) of E. coli in the cecum of CM-fed birds was significantly decreased (P<0.05) compared with that of control birds without changing the CFU of Lactobacillus. In conclusion, dietary supplementation of lower level of CM (0.5%) can be used as a beneficial feed resource without liver toxicity in broiler chicks.

Effects of CPG-oligodeoxynucleotides in Chronic Inflammation and Remodeling of Airway in a Murine Model of Bronchial Asthma (기관지천식의 마우스모델에서 CPG-oligodeoxynucleotides의 기도의 만성염증 및 기도재구성에 대한 영향)

  • Song, So Hyang;Kim, Chi Hong;Dong Hwa, Han;Kim, Seung Joon;Moon, Hwa Sik;Song, Jeong Sup;Park, Sung Hak
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.6
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    • pp.543-552
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    • 2004
  • Background : Airway remodeling of the asthmatic airway, the result of persistent inflammation in the bronchial wall, is associated with irreversible airway obstruction and the severity of asthma. Previous reports had represented that adminitering CpG-oligodeoxynucleotides (CpG-ODN) before sensitization or challenge by allergens inhibits the development of eosinophilic airway inflammation in a murine model of asthma, but the effects of CpG-ODNs on chronic inflammation and airway remodeling had not been characterized. To investigate the influence of CpG-ODNs on chronic inflammation and remodeling of the airway, we performed studies using a murine model of chronic allergen-induced asthma. Methods : Balb/C mice were sensitized to ovalbumin(OVA) and subsequently exposed to nebulized OVA by means of inhalation twice weekly for 7 weeks. CpG-ODNs($30{\mu}g$) was administered intraperitoneally at sensitization. After final inhalation, mice were evaluated for airway hyperresponsiveness, chronic airway inflammation and remodeling. Results : The mice exposed to chronic and recurrent airway challenge with OVA had persistent airway hyperresponsiveness, chronic inflammation and airway remodeling. Mice treated with CpG-ODNs exhibited decreased bronchial hyperresponsiveness, OVA-specific IgE, chronic inflammation and evidence of airway remodeling, including goblet cell hyperplasia and subepithelial fibrosis. Conclusion : CpG-ODNs was thought to prevent chronic inflammation and remodeling changes in a murine model of chronic asthma.

Effect of Maternal Phenylalanine Deficiency on the Growth of Their Offsprings (어미쥐의 Phenylalanine 결핍(缺乏)이 새끼쥐의 성장발육(成長發育)에 미치는 영향(影響))

  • Song, Kyung-Hee;Choi, Hay-Mie
    • Journal of Nutrition and Health
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    • v.14 no.3
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    • pp.129-135
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    • 1981
  • Low phenylalanine diet(0.05%) was given to the Sprague Dawley pregnant rats at the 14 days of gestation and continued until the pups were lactated for 11 days. Body weight, plasma phenylalanine and tyrosine, brain weight, and brain phenylalanine and tyrosine were determined on pups randomly sacrificed at several intervals. Body weight of pups on normal diet (0. 36% phenylalanine) gained rapidly while the pups on the phenylalanine deficient diet decreased and did not survive during the period of 11 days. Brain weight of the pups on the phenylalanine deficient diet was significantly lower(P < 0.05) than the normal pups. Phenylalanine deficient diet did not affect the level of plasma phenylalanine of pups, but it seems that there was a positive correlation between the level of phenylalanine in the diet and the plasma tyrosine level. The plasma tyrosine level of pups on the deficient diet was decreased significantly during the Period while the pups on the normal diet increased steadily. Phenylalanine and tyrosine level in the brain was lower in Pups on the deficient diet than the pups on normal diet but the plasma phenylalanine level was not significantly different in both diets. However, plasma tyrosine level was significantly lower in the pups on the deficient diet than the normal diet at the end of the period.

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The Development and Significance of Physic Gardens in the Late Goryeo and Early Joseon Dynasties (여말선초 약초원의 형성 과정과 조경사적 의미 고찰)

  • Kim, Jung-Hwa
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.5
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    • pp.60-70
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    • 2017
  • This study traces the development of physic gardens in Korea and explores their significance in the history of landscape architecture. For this purpose, records related to physic gardens from medical sources from the period of the Three States to the Joseon dynasty, when herbal medicine was systematized as a field, were searched. Physic gardens had been developed by the time of the late Goryeo and early Joseon dynasties, in the 13th and the 15th centuries. Yakpo(kitchen gardens for medicinal herbs) were cultivated by a group of new high-level officials in the late Goryeo dynasty, when an increasing interest in hyangyak(native herbs) emerged under the influence of the Neo-Confucian perspective on nature, which emphasized locality. The sources analyzed in this study confirm that physic gardens called jong-yakjeon(royal medicinal herb gardens) were in operation in the early Joseon dynasty when policies to investigate, discover, cultivate, and research native herbs were put into place. It is likely that the jong-yakjeon were established at the beginning of the Joseon dynasty as subsidiary facilities under its central medical institutions, the Naeuiwon and Hyeminseo, and then declined in the late Joseon dynasty. Jong-yakjeon can be confirmed to have existed in the mid-15th century. Physic gardens were located in several places outside the Fortress Wall of Hanyang, such as Yakhyeon, Yuldo, Yeoudo, and Saari. The total area encompassed by physic gardens was about 160,000 square meters in the early 18th century. In jong-yakjeon, dozens of medicinal herbs were cultivated, including Schizonepeta tenuifolia var. japonica, Rehmannia glutinosa, and Glycyrrhiza uralensis Fischer, and these gardens were operated by physicians dispatched from the Naeuiwon and dozens of provincial slaves. In conclusion, the jong-yakjeon were similar to the physic gardens of Renaissance medical universities in that they reflected the interest in and development of theories about new herbs, and were similar to the physic gardens of medieval castles and monasteries in terms of species types, location, and function. This paper has limitations in that it does not present the specific spatial forms of the yakpo or the jong-yakjeon. Nevertheless, this paper is significant for the field of garden history because it shows that physic gardens in Korea appeared in the late Goryeo and early Joseon dynasties concomitantly with the development of medicine towards native herbs and functioned as utilitarian gardens to cultivate community remedies.

The Joseon Confucian Ruling Class's Records and Visual Media of Suryukjae (Water and Land Ceremony) during the Fifteenth and Seventeenth Centuries (조선 15~17세기 수륙재(水陸齋)에 대한 유신(儒臣)의 기록과 시각 매체)

  • Jeong, Myounghee
    • Korean Journal of Heritage: History & Science
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    • v.53 no.1
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    • pp.184-203
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    • 2020
  • The Confucian ruling class of the Joseon Dynasty regarded Buddhist rituals as "dangerous festivals." However, these Buddhist ceremonies facilitated transitions between phases of life from birth till death and strengthened communal unity through their joint practice of the rites. Ritual spaces were decorated with various utensils and objects that transformed them into wondrous arenas. Of these ornaments, Buddhist paintings served as the most effective visual medium for educating the common people. As an example, a painting of the Ten Kings of the Underworld (siwangdo) could be hung as a means to illustrate the Buddhist view of the afterlife, embedded in images not only inside a Buddhist temple hall, but in any space where a Buddhist ritual was being held. Demand for Buddhist paintings rose considerably with their use in ritual spaces. Nectar ritual paintings (gamnodo), including scenes of appeasement rites for the souls of the deceased, emphasized depictions of royal family members and their royal relatives. In Chinese paintings of the water and land ceremony (suryukjae), these figures referred to one of several sacred groups who invited deities to a ritual. However, in Korean paintings of a nectar ritual, the iconography symbolized the patronage of the royal court and underlined the historicity and tradition of nationally conducted water and land ceremonies. This royal patronage implied the social and governmental sanction of Buddhist rituals. By including depictions of royal family members and their royal relatives, Joseon Buddhist paintings highlighted this approval. The Joseon ruling class outwardly feared that Buddhist rituals might undermine observance of Confucian proprieties and lead to a corruption of public morals, since monks and laymen, men and women, and people of all ranks mingled within the ritual spaces. The concern of the ruling class was also closely related to the nature of festivals, which involved deviation from the routines of daily life and violation of taboos. Since visual media such as paintings were considered to hold a special power, some members of the ruling class attempted to exploit this power, while others were apprehensive of the risks they entailed. According to Joseon wangjo sillok (The Annals of the Joseon Dynasty), the Joseon royal court burned Buddhist paintings and ordered the arrest of those who created them, while emphasizing their dangers. It further announced that so many citizens were gathering in Buddhist ritual spaces that the capital city was being left vacant. However, this record also paradoxically suggests that Buddhist rituals were widely considered festivals that people should participate in. Buddhist rituals could not be easily suppressed since they performed important religious functions reflecting the phases of the human life cycle, and had no available Confucian replacements. Their festive nature, unifying communities, expanded significantly at the time. The nectar ritual paintings of the late Joseon period realistically delineated nectar rituals and depicted the troops of traveling actors and performers that began to emerge during the seventeenth century. Such Buddhist rituals for consoling souls who encountered an unfortunate death were held annually and evolved into festivals during which the Joseon people relieved their everyday fatigue and refreshed themselves. The process of adopting Buddhist rituals-regarded as "dangerous festivals" due to political suppression of Buddhism in the Confucian nation-as seasonal customs and communal feasts is well reflected in the changes made in Buddhist paintings.

Iconography and Symbols of the Gwandeokjeong Pavilion Murals in Jeju (제주 관덕정(觀德亭) 벽화의 도상과 표상)

  • Kang, Yeongju
    • Korean Journal of Heritage: History & Science
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    • v.53 no.3
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    • pp.258-277
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    • 2020
  • The purpose of this paper is to examine the paintings and symbols of the Jeju Guandeokjeong murals, Treasure No. 322. Gwandeokjeong Pavilion in Jeju is one of the oldest buildings in Jeju and was built in 1448 during the reign of King Sejong (世宗) of the Joseon Dynasty to serve as a training ground for soldiers. Unlike Gwandeokjeong Pavilions in other regions, Jeju's Gwandeokjeong Pavilion has a long history and is of cultural value due to its beautiful architecture. In addition, it contains various murals which are a further source of attention. There are four murals on the front and back of the two Lintels on the left and right sides of the building. Their contents include of 『The Three Kingdoms (三國志)』 and and on the back. Towards the right, is depicted, with on the back. Based on a replica of the murals from 1976, the plan, style, and age of the Gwandeokjeong Pavilion murals have been studied, together with their meanings. The contents of the mural are broadly divided into five parts, which are identified by the tacit signatures atop the screen, which provide such details as the painting titles. The paintings on the left and right sides of the center appear to inspire the spirit of the military's commerce in order to boost soldiers' morale, protect the country, and protect the people in line with the purpose of Gwandeokjeong Pavilion. The following and figuratively depict guidelines for the behavior and mindset of officials. In particular, is a painting concerned with concepts of longevity and an auspicious (吉祥), which shows how court paintings became popular as folk paintings at that time. The paintings of tangerines and other specialties of Jeju Island, the ritual paintings of Jeokbyeokdaejeon, and the expressions of Mt. Halla (漢拏山) and Oreum (오름) indicate the existence of Jeju artists that belonged to the Jeju government office at that time. The five themes and styles of the murals also show that the murals of Gwandeokjeong Pavilion were produced in the late 19th and early 20th centuries.

The Rusticity and Spirit of Scholars Found at Suwoojae, the Birth House of Garam Byungi Lee (가람(嘉藍) 이병기 생가(李秉岐 生家) 수우재(守愚齋)에서 찾는 소박함과 선비정신)

  • Kim, Jung-Sik;Rho, Jae-Hyun;Kim, Jeong-Moon;Oh, Hyun-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.1-11
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    • 2010
  • This study examines the authentic meaning, location, garden layout, and structural characteristics of Suwoojae(守愚齋), the birth house of Garam Byungi Lee, which was the very epitome of the traditional house structure based on literature review, field survey, and the existing measured drawings. The followings explain how rusticity and spirit of scholars, the core concepts of Garam's poetry, were featured in structural and spacial arrangements of Suwoojae as well as its location and physical layout. 1. Suwoojae is enclosed by Cheonho mountain which fans out of Noryoung mountains in East and located on the tail of Yongwha mountain in West. It has proved to be Yangtack Myoungdang according to the Poongsoo theory, Inguljiryoungron; The energy of earth at a certain location results in the better fortune together with the energy emitted from human body. 2. Suwoojae is an official local monument which was built in 1844, late Joesoen Dynasty by Joheung Lee, Garam's grandfather. Some parts of inner-structure connect with the kitchen in the shape of called Gopae. Suwoojae consists of 4 Sarangchae, 3 Gobangchae, and a Jangdokdae behind Anchae. 3. Since inner and outer walls of Suwoojae are distinctly separate from the main structure, its look varies significantly from different angles. Suwoojae, in its entirety, discloses Garam's philosophy, ideas, and ideology on life and the universe. 4. Apricot trees, Japanese-magnolias, aromatic-trees, crape myrtle, white-magnolias, camellia-trees were planted on the left of the walls, and persimmon trees, jujube trees, plum trees, quince trees were at the inner-yard. Especially, trifoliate orange trees a natural monument of Jeonrabukdo draw substantial attention from visitors. 5. The main garden facilities are located in front of Sarangchae: A rectangle pond(14.72m in length and 3.87m in height), the surroundings of the pond and Anchae, rocks that have distinctive shapes. In general, the garden was designed to incorporate the scenery around Suwoojae as a part of its structure and contain the love for nature and aesthetic sense. 6. It seems that the natural surroundings of Suwoojae had helped form motives of Garam's poetry and assisted him in finding subject-matters and identifying the themes of his works. This is well revealed in his poem, Seungwoonjungee.

Embryonic and Larva Development of Slime Flounder, Microstomus achne (찰가자미(Microstomus achne)의 난발생 및 자치어 형태 발달)

  • Byun, Soon-Gyu;Lee, Sung-Hun;Hwang, Jae-Ho;Han, Kyeong-Ho;Kang, Kyeong-Wan;Kim, Jin-Do;Kim, Yi-Cheong;Lee, Bae-Ik
    • Development and Reproduction
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    • v.13 no.4
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    • pp.281-289
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    • 2009
  • The slime flounder Microstomus achne were caught at Geomun Island, Yosu-si, Jeollanamdo from January to March in 2006. The fertilized eggs were observed for morphological development of egg, embryo and larva. Eggs were colorless transparent, separative pelagic, absent of oil globule, and the diameter was 1.64${\pm}$0.03 mm (n=50). The eggs were hatched at 168 hours 40 minutes after fertilization in the range of $9.8\sim13.0^{\circ}C$ (mean $11.4{\pm}1.6^{\circ}C$). Total length of newly hatched larva was 4.05${\pm}$0.18 mm (n=20). The larva had developed membranous fin showing waterdrop-shaped structure, and their mouth and anus were not open. The myotomes were 14~15+33~34=47~49. The egg yolks were 1.64${\pm}$0.12 mm in major axis, and 1.23${\pm}$0.19 mm in minor axis. At 12 days after hatching, the total length was 7.32${\pm}$0.42 mm(n=20). The egg yolk was completely absorbed and transferred to post larval stage. Star-shaped melanophores and branch-shaped xanthophores in the edge of membranous fin were more densed. Chrysanthemum-shaped melanophores in the notochord were densed and formed 4~5 melanophore bands. At 90~93 days after hatching, morphological features of the larva, 19.91${\pm}$1.63 mm TL(n=20), were transferred to juvenile stage showing similar features with those of the adult fish.

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