• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.419-424
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• 2015

In order to determine the ovarian cycle of Asian Toad, Bufo gargarizans, the developmental stage based on the gonadosomatic index (GSI), size of follicle oocytes in ovary and vitellogenesis for adult females were investigated all around the year. The weight of ovary and GSI were the lowest from April, and all follicle oocytes exist in the pre-vitellogenic form, indicating that the vitellogenesis was suspended. The follicle oocytes in early-vitellogenic stage appeared in ovary during may when the weight of ovary and GSI start to increased, and the follicle oocytes in mid-vitellogenic and pre-vitellogenic stages existed during June and the weight of ovary and GSI also increased. This indicates that vitellogenesis has been carried out actively during this period. The follicle oocytes in mid-vitellogenic stage and late-vitellogenic stage when the vitellogenesis was also completed existed on September. Post-vitellogenic follicle oocytes after vitellogenesis started to appear from October and rapidly increased from December in hibernation. The full grown follicle oocytes existed during February, indicating the ovarian cycle that all follicle oocytes in ovary are developed separately, not synchronized, during the growing period of follicle oocytes and the post-vitellogenic follicle oocytes are maintained the ovulation period.

• The Journal of the Acoustical Society of Korea
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• v.11 no.2
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• pp.28-37
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• 1992

In the study, the Acoustic transducer of a thin circular disc-type with PZT/Metal was manufactured. The 'tape casting method' was introduced to prepare the thin disc-type of piezoelectric ceramics. The acoustic characteristics of PZT/Metal acoustic transducer for piezoelectric buzzer and piezoelectric speaker etc. have been studied and analyzed. As a result, the sound pressure level (dB), in the range from -6dB to -14dB, increased with increasing the piezoelectric coeffeicient ($d_{31}$) of ceramics. The optimal conditions of the sound pressure characteristics of acoustic transducer were that the radius ratio(${\eta}$) of ceramics and metal plate is 0.7-0.8 and the thickness ratio(${\beta}$) is 1.0, and the value were -15~-165dB.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.381-388
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• 1999

Herpetofauna of Kojedo was surveyed in both May 3, 1998~May 5, 1998 and Nov. 7, 1998~Nov. 8, 1998. 9 species of 6 families in Amphibia and 9 species of 3 families in Reptile were observed by survey and heard the evidence in this study. It was observed relatively rich biota to the Kayasan, Sokrisan, Soraksan and Chirisan National Park in Korea. There were Specific Endangered Animal assigned by Minister of Environment such as Hynobius leechii, Bufo bufo gargarizans, Rana dybowskii, Elaphe rufodorsata, Zamenis spinalis, Dinodon rufo-zonatum rufozonatum, Agkistrodon blomhoffii bevicaudus and Agkistrodon saxatilis. Especially Rana catesbeiana which was originated from North America was very abundantly distributed at one pond. So Rana catesbeiana should be controlled for stable environmental condition of endemic Amphibia distribution.

• The Korean Journal of Zoology
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• v.15 no.3
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• pp.105-110
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• 1972

A cellulosse acetate electrophoretic survey of Korean Anura has revealed the presence of diverse lactate and malate dehydrogenase (LDH and MDH) isozymes. The pattern of LDH and MDH isozymes in the tissues of the central nervous system of the six species of Anura examined are species specific and differ from those of mammals and birds. Both Rana nigromaculata nigromaculata and Rana nigromaculata coreana have two molecular forms of LDH and MDH, respectively, with almost the same pattern. Whole brain homogenate of Rana temporaria shows also a maximum of only two LDH isozymes. Both Bufo bufo asiaticus and Bombina orientalis have five molecular forms of LDH with an entirely different spacing on the zymograms, whereas Rana rugosa has three. Two molecular forms of MDH are present in all animals examined and one band is shown in olfactory lobe and mixture of cerebellum and medulla oblongata of Rana nigromaculata nigromaculata.

• Journal of the FoodService Safety
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• v.4 no.2
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• pp.60-66
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• 2023

This study was to suggest the roles of social enterprises in maintaining healthy life of the socially vulnerable by creating a customized care environment through chronic disease diet management targeting the elderly at home in need of care in the community. As for the subjects of this study, 102 in-home elderly people aged 65 or older (14 males & 88 females) who needed care in the community were provided with a diet management lunch box delivery service customized for chronic diseases. Theoretical education and cooking class on chronic diseases were provided to 15 volunteers with 10 sessions, and customized lunch boxes were provided to the elderly with chronic diseases at home on that day. In conclusion, it is believed that only by increasing the level of knowledge about chronic diseases and nutritional knowledge of the elderly will it be possible to establish a proper meal plan. Since the role of volunteers is important, it is necessary to systematically seek nutritional education methods for volunteers.

• Applied Microscopy
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• v.20 no.2
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• pp.81-101
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• 1990

Toad bladder의 상피수송(上皮輸送)을 분석(分析)하기 위하여 동결치환(凍結置換) 및 동결절단법(凍結切斷法)을 적용(適用)하여 전자현미경(電子顯微鏡) 관찰(觀察)을 실시하였다. 방광(膀胱)의 점막층(粘膜層)은 과립성세포(顆粒性細胞), 미토콘드리아가 풍부한 세포, 점막분필세포(粘膜分泌細胞) 및 기저세포(基底細胞)등 4가지 세포로 구성되어 있었다. 과립성세포(顆粒性細胞)는 점막표면적의 대부분을 점유하며 $Na^+$ 수송(輸送)에 주요한 역할을 하고, 정단부(頂端部)의 세포질에는 다수의 과립이 분포하며 정단세포막(頂端細胞膜)은 microvilli type I로 배열되어 있고, 표면에 glycoprotein을 함유하는 세포외막(細胞外膜)이 관찰되었다. 대조적으로 미토콘드리아가 풍부한 세포는 세포질 전역에 걸쳐 다수의 미토콘드리아가 분포해 있으며 주요 기능은 $H^{+},\;K^{+}$ 및 $HCO_{3}^{-}$ 분필수송(分泌輸送)에 관여할 것으로 생각되며 이들 수송상피(輸送上皮)는 정단부가 견고연접(堅固連接)으로 둘러 싸이고 기저세포막(基底細胞膜)은 인접세포와 서로 분리되므로 상피세포의 극성이 유지되며 정단부(頂端部) 세포막과 기저세포막의 수송특성(輸送特性)은 각기 다르다고 생각된다. 따라서 두꺼비 방광(膀胱)에서 상피수송(上皮輸送)은 세포 통과수송 및 세포간 분류수송 경로를 나타내고 있다. 한편 세포막 투과성(透過性)의 조절과 관련하여 동결절단(凍結切斷) 전자현미경 관찰에 의하면 forskolin에 촉진된 정단부(頂端部) 세포막 투과성의 변화는 세포막내(細胞膜內) 입자(粒子)의 분포와 밀접한 관계를 가지는 것으로 보인다. 특히 과립성세포(顆粒性細胞)에서 집단으로 관찰되는 세포막내(細胞膜內) 입자(粒子)는 forskolin에 유도된 정단세포막(頂端細胞膜) 투과성의 변화를 나타내주는 것으로 사료되나 이의 기능적 의미에 대하여는 연구가 더욱 필요하다고 본다.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.17-26
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• 2000

The regional distribution and relative frequencies of endocrine cells were studied immunohistochemically (PAP methods) in the alimentary tract and pancreas of the toad, Bufo bufo gargarizans Cantor using specific antisera against bovine Sp-1/chromogranin (BCG), serotonin, bombesin, gastrin, substance P (SP), somatostatin, insulin, glucagon, pancreatic polypeptide (PP), vasoactive intestinal polypeptide (VIP) and secretin. Nine kinds of endocrine cells were identified in this study. Spherical or spindleshaped immunoreactive (IR) cells were located in the gastric glands of stomach regions, in the basal portion of the epithelium of intestinal tract or esophagus, and in the exocrine or pancreatic islets with variable frequencies. In the alimentary tract, BCG-IR cells were found in the fundus and pylorus with rare and a few frequencies, respectively. Serotonin-IR cells were demonstrated in the whole alimentary tract including the esophagus. Bombesin- and SP-IR cells were restricted to the stomach regions and gastrin-IR cells were restricted to the pylorus. Somatostatin-IR cells were detected throughout the whole alimentary tract except for the large intestine, However, insulin-, glucagon-, PP-, VIP- and secretin-IR cells were not detected in the alimentary tract. In the pancreas of toad, the distribution and relative frequency of endocrine cells were similar to those of other mammals. Insulin-IR cells were located in the central portion of the pancreatic islets and interspaces of exocrine portions, and glucagon-, somatostatin- and PP-IR cells were detected in the marginal regions of the pancreatic islets and interspaces of exocrine. However, other IR cells were not found in the pancreas. In conclusion, the regional distribution and relative frequency of the endocrine cells in the alimentary tract and pancreas of the toad were similar to other anuran species but some differences which might be caused by feeding habits and species specification were also observed.

• Korean Journal of Environment and Ecology
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• v.21 no.2
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• pp.107-112
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• 2007

This study was carried out to investigate the herpeto-fauna at Hallasan National Park. We conducted a survey at 1100 Resting places, Eoseungsaengak, Donnaeko, Eorimok, Yeongsil, Gwaneumsa and Seongpanak from April, 2006 to January, 2007. A series of four families and 5 species of amphibians and 4 families and 8 species of reptiles were observed. Amphiesma vibakari ruthveni, Takydromus wolteri, Scincella vandenburghi, Coluber spinalis and Hynobius quelpartensis which are rarely appearing inland but they were frequently observed by this survey. Also, we observed Sibynophis chinensis that only inhabits Jeju island with in Korea. Jeju island has both southern and northern boundary lines for amphibians and reptiles. Amphibians and reptiles in Jeju island have a different from those inland and valuable information for biogeograpy due to dissimilar climate and isolation from continental for a long time. It is not certain whether some amphibians and reptiles, Bufo gargarizans, Rana rugosa, R. plancyi, Elaphe rufodorsata and Takydromus amurensis, inhabit Jeju island, as recorded in previous literatures, so the research on current status of them has to be carried out immediately.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.1-20
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• 2023

The present study has monitored the changes in the biodiversity of Dunchon-Dong ecological and landscape conservation area after the restoration of the wetland, identified and analyzed the threats to the ecosystem, and presented a management plan accordingly. In this area which was forests and rice paddies in the past, apartment reconstruction is currently underway, with some hinterland forests and wetlands remaining. When we look into the change in the floras, the total number of species was 193 in 2000 before the restoration, it decreased from 2004 to 2006, and as of 2019, it was 149, showing an increasing trend. The result of comparing the species that emerged before and after the restoration showed an increase in Cyperaceae herbs such as Carex maximowiczii and Carex dispalata growing in wetland areas within forests and Schoenoplectiella juncoides and Schoenoplectus tabernaemontani growing in areas within wetlands where shallow water is maintained. As a result of analyzing the change in the area ratio of each type of extant vegetation, the wetland native herbs formed the power at the highest ratio after the restoration. The change in the power of the wetland native herbs was on an increasing trend until 2007, after which it decreased much in 2010 and then gradually increased, showing values of 26.6% in 2000, 44.6% in 2002, 49.0% in 2005, 53.3% in 2007, 28.7% in 2010, and 37.3% in 2019. The cause of the decrease in 2010 was judged to be due to the vegetation management conducted to secure open water and remove organic matter in freshwater reservoirs. The amphibia which emerged from 2000 to 2019 was a total of 9 species including Hynobius leeshii, Bufo gargarizans, Kaloula borealis, and Rana uenoi. As a result of the changes in the emerging wild birds, the species diversity index before the restoration was 0.9922 in 2000, and the species diversity index after the restoration gradually increased to 1.2449 in 2005, 1.2467 in 2010, and 2.2631 in 2019. The amphibia and wild birds inhibiting in the Dunchon-Dong forest and wetland were judged to have increased through continuous wetland maintenance such as naturalized plant removal management, native plant maintenance, and open water securing management. For the ecosystem preservation management of the Dunchon-Dong ecological and landscape conservation area, it was suggested to minimize the impact of the Dunchon-Dong reconstruction project, reorganize the indiscriminate access roads adjacent to the wetland, and reorganize the main entrance to the wetland. For ecosystem restoration management, systematic restoration and ecological buffer planting were suggested to be carried out at the time of construction fence demolition.

• Journal of Life Science
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• v.26 no.3
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• pp.359-363
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• 2016

We have screened four natural products against 640 single compounds, which shows more two folds gene expression for both endoplasmic reticulum aminopeptidase 1 (ERAP1) and FOXO-family transcription factor (FOXO1). The results were as follows. (±)-Car-3-ene-2,5-dione from Asarum sieboldii Miq. is C₁₀H₁₂O₂ molecular formula and the 164 kDa molecular weight. Cinobufagin from Bufonis Venennum is C₂₆H₃₄O₆ molecular formula and 442 kDa molecular weight. So far reported main biological function is Na⁺/K⁺-ATPase inhibition. Corilagin from Euphorbia pekinensis is C₂₇H₂₂O₁₈ molecular formula and 634 kDa molecular weight. Carbonic anhydrase inhibition is well known its biological function. Corydaline from Corydalis turtschaninovii is C₂₂H₂₇NO₄ molecular formula and 369 kDa molecular weight. The main biological function is acetylcholinesterase inhibition. In the short future, four types of natural products will be used in longevity experiments with insects. The results may give one of the clues for studying new drug development candidates of the longevity.