• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.311-319
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• 2008

To understand the relative immigration activities (RIA) of hibernal diatom community in Lake Ilgam (at the station with and without macrophyte) and River Han (at the station with different current and nutrient), a natural and artificial bed substrate was deposited from 15 to 29 January 2008. For the study period, both waters comprised huge biomass of diatom, over 75% of total abundance. Nutrients in water column, ash-free dry matter (AFDM) and chlorophyll-a (Chl-a) concentration in substrates were decreased with increasing of current in rivers, while in lakes the macrophyte largely affected the diatom community and water quality. Algal RIA in rivers was high at stations with high concentration of nutrient, AFDM and Chl-a, and in high nutrients and no macrophytes in lakes, respectively. The species showing a higher RIA was Nitzschia amphibia in rivers and Aulacoseira italica in lakes, while the dominant species were Navicula sp. in rivers and Syndera acus in lakes, suggesting no relationship between water algal biomass and its RIA. These results suggest that the RIA of stream diatom community depends exclusively on the current, while the planktonic diatom in lake was of the macrophyte.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.1
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• pp.1-15
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• 2001

The purpose of this study is to evaluate the creation techniques of eco-pond, one of biotopes to promote biodiversity in urban residence area. Investigation were classified out plant, mammals, amphibia, reptiles, birds, fishes and insects. The results were summarized as follows: Around the eco-pond shows simple vegetation structurs, consisted of Pinus densoflora S et Z. and Robinia pseudoacacia under competition. In case of shrub, consisted of 4 species but plant growing appearence diversely by seasons. The evaluation of vegetation of eco-pond, there are found 4 species of aquatic plants. Inside the revetment of pond, Echinochloa crus-galli, Persicaria hydropiper, Digiaria sanguinalis, Cyperus microiria and Bidens frondosa L. are mainly distributed. Near the revetment, Trifolium repens L. and Digiaria sanguinalis are prevailed. And in its background, Erigeron canadensis, Erigeron annuus and vines are begins to make their appearances. When evaluation animals in eco-pond and contrast plot, it show simple species and numbers of mammals. It seemed to be resulted from its isolation and outside intervention by users In eco-pond, Pica pica and Streptopelia orientalis are mainly found and in contrast plot of Columba livia, which are so strong adaptation to city life environment. In case of amphibia and reptiles, none is observed in contrast plot, but in ecological pond, Rana nigromaculata and Hyla japonica are constantly observed. In case of insects, more species are found in eco-pond than contrast plot. And in eco-pond, more dragonflies are visibly increased one year after its construction. In floral zone inside of pond revetment, grasshopper and Locusta migratoria are frequently observed. In case of butterflies, they are mainly found in log fence and willow(salix) around eco-pond. In case of fishes inside of eco-pond, the species and its density are remarkable increased one year after the construction. With above evaluation results, we have identify the increase effect of biodiversity after construction of the eco-pond.

• Korean Journal of Environmental Biology
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• v.29 no.1
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• pp.1-10
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• 2011

Amphibian population declines globally. Aquatic contamination by organic pollutants including endocrine disrupters has been suspected to the one of the reason for distinction of amphibia which has obligate aquatic life style during larval period. Amphibians have been widely accepted as animal model for the study of endocrine disruption in aquatic ecosystem at molecular as well as individual levels. There are increasing need for toxicological data in amphibians at multiple endpoints for management of contamination and development of safety guideline for important EDs in aquatic media. Alkylphenols have been widely used in agricultural, industrial, and housekeeping activities, contaminating the aquatic media and evoking endocrine disruption in aquatic animals. In this review, we summarized data concerning the endocrine disruption by alkylphenol organic pollutants on amphibians according to route, concentration, terms, and developmental stage of exposure together with mechanism of endocrine disruption.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.91-102
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• 2010

Water quality and epiphytic diatom on the submerged stems of reed (Phragmites communis), which occupy 90% of the Donghwa wetland macrophytes were monthly monitored at three points such as inflow stream, high- and low-level wetlands, and outflow stream between March and October, 2005. 1) A diverse and high density of diatom species observed in the cold-season, especially Nitzschia palea and Nitzschia amphibia dominated the diatom community without wetlands. 2) High DAIpo and TDI indices were measured over the sampling periods and stations, regardless of nitrogen increase and phosphorus increase through the wetlands. 3) Higher density of diatom species in high wetland than low wetlands was attributed in the enough nutrients and light penetration by low growth of reed. Therefore, epiphytic diatom of reed stem in Donghwa wetland, where high nutrients released from the sediment and reed debris after the death of macrophytes, flourished with low canopy of low reed vegetation.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.188-195
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• 1991

The effect of lanthanum ion (La3 +), which is associated with the mobilization of internal calcium, on the regulation of oocyte maturation was investigated with Rana dybowskii follicles. Follicular oocytes matured (germinal vesicle breakdown, GVBD) dose dependently when they were exposed to La3+ (O.O1-1.O mM) and the maturation occurred in 9-12 hours after the la3+(0.33 mM) stimulation. lanthanum also accelerated the onset of maturation of the lollicular oocytes exhibiting spontaneous maturation. Three hours of exposure to La3+ was enough to induce the maturation. The La3 + -induced maturation was not associated with progesterone production by follicle cells, and the maturation was inhibited by forskolin (9 $\mu$ M), and cyclobeximide (0.01 - 1.0 - $\mu$g/2 ml) in the medium. The La3+ and hormone stimulated maturation showed the same patterns of protein phosphorylation and dephosphorylation during the maturation. The data suggest that the oocyte maturation by La3+ stimulation is very similar to that by progesterone. Thus, it seems that internal mobilization of Ca2+ plays a key role in the initiation of oocyte maturation in amphibia.

• The Korean Journal of Zoology
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• v.34 no.4
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• pp.433-451
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• 1991

척추동물(7목 23종)의 췌장에서 insulin( B)세포, glucagon(A)세포, somatostatin( D)세포 및 pancreatic polypeptide( PP)세포 등을 면역세포화학법으로 동정하여 이들의 출현율, 분포양상 및 형태 등을 계통별로 비교하였다. 파충강의 거북목, 양서강의 유미목 및 어강의 악상대목 들을 제외한 모든 종에서 췌도의 형성을 관찰할 수 있었으며, 췌도를 구성하는 내분비세포의 크기에는 계통간의 차이가 있었다. B세포는 파충강의 것이 가장 크고, 양서강, 어강의 순이 었으며 A와 PP세포는 양서강, 파충강 및 어강의 순서였다. D세포는 양서강의 것이 가장 윤고, 다음이 어장이었으며, 파충강의 것이 가장 작았다. 이들 세포의 모양은 B세포의 경우 양서강과 어장에서는 원형, 난원형 및 방추형이었으며, 파충강에서는 원추형 및 단기형 등 다양한 모습이었다. A세포는 어강에서는 원헝, 난원형 및 방추형이 고르게 나타났고, 파충강과 양서 강에서는 원주형, 다각형 및 쐐기형이 나타났다. D세포는 모든 동물에서 원형, 난원형 및 방추형이 관찰되었고, 특히 파충강에서는 원추형및 쐐기형도 나타났다. PP세포는 주로 방추형 및 반원형이 대다수이였으며 간혹 원형 또는 다각형 등의 모습도 나타났다. 각 내분비세포의 출현율은 파충강 열 어강 들에서는 B, A, D 및 PP세포 순이었으나, 양서 강에서는 B, A, PP 및 D세포 순으로 나타났다. B와 PP세포는 양서강, 어강 및 파충강 순서로 출현하였고, A세포는 파충강, 어강 및 양서강의 순서이었으며 D세포는 어강, 파충강 및 양서강의 순서였다. 췌도 내에서의 세포의 분포 위치는 세포의 종류에 따라 차이를 보여 B세포의 경우 대다수 동물들에서 중앙부에 균등하게 분포하였으나 A, D및 PP세포는 주로 췌도 주변부에 분포하였고, 어강에서의 D세포는 췌도 중앙부에서도 관찰되었다. 일반적으로 파충강 및 양서 강에서는 외분비 선포조직에서초 내분비세포들이 출현하였으나, 어강에서는 내분비세포가 전혀 출현하지 않았다. 양서강 및 어강 들의 일부 수에서는 췌관상피에서도 드물게 나타났다.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.174-181
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• 1994

3 종의 한국산개구리를 사용하여 여포들이 생성하는 스테로이드와 난자의 성숙능이 번식기 근처에서 어떻게 변하는가를 조사하였다. 개구리의 여포를 생체외 배양하면서 이들이 뇌하수체추출물(frog pituitary homogenate, FPH) 혹은 CAMP의 자극으로 생성하는 progesterone(Pa)과 testosterone(T)의 양을 측정하여 이로부터 P4yT의 비율을 구하였으며 여포난자들이 FPH. P4 혹은 12-0-tetrsdecanoyl phorbol-13-acetate(TPA)에 반응하여 성숙을 일으키는 시기를 조사하였다. 북방산개구리의 여포난자는 11월 부터 호르몬에 반응하여 성숙을 일으켰으며 2월에 PJT의 비율이 급격히 증가하였다 참개구리는 5월에 가서of PJT의 비율이 현저히 증가하고 FPH에 반응하여 성숙을 일으켰다. 그러나 P4에 의한 난자성숙은 3월부터 시작하였다 옴개구리는 7월에 P4/T 비율의 증가가 있었으며 이때부터 또한 TPA에 반응하여 난자의 성숙을 일으켰다 따라서 3종의 개구리에서 모두 각각의 번식기 근처에서 PJT의 비가 급격히 증가하고 또한 성숙능이 생긴다는 것을 알 수있었다.

• Animal cells and systems
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• v.6 no.4
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• pp.287-292
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• 2002

Functional characterization of sex pheromones in olfactory responses is essential for the study of chemical communications in amphibians. Using Y-maze olfactory preference tests, we have investigated the olfactory res-ponses of male and female red-spotted newts, Notophthalmus viridescens, to the crude extracts of the opposite sex's genial and cloacal pheromones. Both male and female cloacal pheromone extracts caused the opposite sex to initiate olfactory responses by leaving the starting area in the Y-maze, but only subject males exposed to female cloacal pheromone extracts completed olfactory choice by entering the side arm of the Y-maze which received the pheromones. For genial pheromone extracts, only female genial pheromone extracts induced initial olfactory responses from test males. Neither male nor female genial pheromone extracts made the oppo-site sex complete olfactory choice. Pre-exposure of test females to male pheromone extracts increased the likelihood of initial olfactory responses. The latency for initial olfactory responses of test females that were previously exposed to male genial extracts was significantly shorter than that of control females.

• The Korean Journal of Zoology
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• v.36 no.1
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• pp.109-115
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• 1993

본연구는 북방산개구리 여포난자의 자발적 성숙과 관련된 몇가지 요인들에 대해 조사하였다. 자발적 성숙을 일으키는 여포에서 여포조직을 제거하여 denuded 난자를 만든다음 배양했을 때에는 자발적 성숙을 일으키지 않았다. 이들 denuded 난자에 frog pituitary homogenate(FPH, 0.05 gland/ml)를 처리하여도 역시 성숙이 일어나지 않았으나 progesterone(P4, 0.5 Ig/ml)을 처리하였을 때에는 성숙이 일어났다. 동면기간에 여포들이 생성하는 P4와 testosterone(T)의 양을 측정해본 결과 동면초에는 비슷한 양의 P4와 T를 생성하였으나 후기에는 P4만 생성하고 T는 거의 생성하지 않았다. 배양액에 estradiol을 첨가하면 농도에 의존하여 FPH에 의해 촉진된 P4의 생성을 억제할 뿐 아니라 성숙도 비가역적으로 억제하였다. 배양액에 첨가한 hvpoxanthine은 CAMP와 항진적으로 난자의 성숙을 억제하였다. 이러한 결과들은 자발적 성숙과정에 여포세포와 P4/T 비율의 증가가 중요한 요인이 된다는 것과 일반적인 난자성숙억제제는 자발적 성숙을 역시 억제한다는 것을 보여준다.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.66-74
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• 2004

In order to clarify intra-and inter-specific variation of Korean Rana species, the partial DNA sequences of mitochondrial 16S rDNA gene were determined from 6 Korean and 1 Japanese Rana species, DNA sequences from Korean and Japanese species were comparison-analysed within, and also with the sequences from three species of Japanese brown frogs. DNA similarities were calculated as 91.3∼97.3％ among brown frog (R. amurensis coreana, R. dybowskii and R. huanrenensis), as 96.11∼97.26％ among pond frogs (R. nigromaculata and R. planeyi chosenica). Genetic distance of pond frog and wrinkle fyog (R. rugosa) were near than that of pond frog and brown frog. Two clusters were formed brown frogs and the other group by neigh-bor-joining and maximum-likelihood analysis, also the populations of R. nigromaculata were well distinguished between Korean peninsula and Korean island. But result from maximum-likelihood analysis slightly differed from neighbor-joining to cluster of R. rugosa. Further analyses for their population will be necessary to study the phylogenetic status.