• 환경영향평가
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• 제18권3호
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• pp.123-129
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• 2009

In Korea the population of breeding house swallow is continuously decreasing. In this regard this study was conducted to find out the overall population trend during 2001-2005. The areas of urban and rural sites were separated to estimate population. Also the sites in Yangpyung areas were chosen to compare population density between two sites during Mar-Aug, 2006. The house swallow had two breeding periods and I tried to correlated amount of days of incubation and number of eggs in the nest. After egg hatching the homing behavior also was estimated assuming lack of foods takes longer to bring foods back to the nest. This study signified that a long term study should be conducted for population change and spring arrival time due to climate change in Korea.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제3권2호
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• pp.163-171
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• 1996

Observing that a locally weakly Lindel$\"{o}$f space is a quasi-F space if and only if it has an F-base, we show that every dense weakly Lindel$\"{o}$f subspace of an almost-p-space is C-embedded, every locally weakly Lindel$\"{o}$f space with a cocompact F-base is a locally compact and quasi-F space and that if Y is a dense weakly Lindel$\"{o}$f subspace of X which has a cocompact F-base, then $\beta$Y and X are homeomorphic. We also show that for any a separating nest generated intersection ring F on a space X, there is a separating nest generated intersection ring g on $\phi_{Y}^{-1}$(X) such that QF(w(X, F)) and ($\phi_{Y}^{-1}$(X),g) are homeomorphic and $\phi_{Y}_{x}$(g$^#$)=F$^#$.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1996년도 한국생물과학협회 국제학술대회
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• pp.129.2-129
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• 1996

• 환경생물
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• 제35권2호
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• pp.134-142
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• 2017

난도는 괭이갈매기 번식지 중 하나로 천연기념물로서 보호되고 있다. 본 연구에서는 난도에서 번식하는 괭이갈매기 개체군과 서식지 현황을 파악하기 위해서 2015년 7월부터 11월까지 조사하였다. 둥지 밀도를 이용하여 번식 개체군을 산정하였다. 괭이갈매기는 $1m^2$당 평균 0.51쌍이 번식하고 있었으며 약 26,760개체가 난도에 번식하고 있는 것으로 추정된다. 난도의 우점식생은 돌피와 개밀이었으며 괭이갈매기가 은신처나 둥지장소로 이용하고 있었다. 번식기간 중 괭이갈매기의 주된 먹이는 멸치 (48%)로 보인다. 그 밖에 난도에서 번식하는 바닷새로는 슴새, 가마우지, 바다제비 등을 확인할 수 있었다.

• Journal of Ecology and Environment
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• 제30권4호
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• pp.341-346
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• 2007

Nest density was determined and tree and soil characteristics around Nycticorax nycticorax breeding sites and non-breeding sites on Bamsum Island in Seoul were analyzed from May 2005 to October 2006 to identify breeding site preferences of N. nycticorax and the effects of N. nycticorax nesting density on nesting tree structure and soil characteristics. N. nycticorax preferred trees of low height ($3.5{\sim}6$ m) and small diameter at breast height in high density Salix communities. Excrement of heron juveniles was dropped on the soil under the nests. The soil nutrient content under nests (P: 126.0 mg/kg, N: 202.8 mg/kg, EC: 549 ${\mu}S/cm$, pH 4.7) was much higher than that of control soils from Bamsum Island not enriched by heron excrement (P: 41.5 mg/kg, N: 42.0 mg/kg, EC: 342 ${\mu}S/cm$, pH 5.1). Formation of Salix communities on the shores of Bamsum Island is ongoing, and their structure has been directly influenced by annual flooding. After flooding, the nutrient content differences between heron-affected soils and control soils were not significant. This might be the reason that Salix communities on Bamsum were not affected by nesting herons as in other terrestrial communities where herons nest. This result indicates that flooding plays an important role in sustaining Salix communities on Bamsum Island where herons nest. The results of this study may increase understanding of N. nycticorax breeding behavior which may be useful for conservation planning.

• 한국발생생물학회지:발생과생식
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• 제21권1호
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• pp.101-110
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• 2017

On June 14, 2008 (the first experiment) and July 24, 2008 (the second experiment), the shores of the Boseong River and the sandy beaches, Seokgok-myun, Moksadong-myun, Gokseong-gun in Jeollanam Province were investigated and a total of 29 soft-shelled turtle (Tryonyx sinensis) eggs in the natural spawning nest eggs were collected (13 eggs were collected in the first experiment and 16 eggs in the second experiment). The temperatures in the natural spawning nests were $25.9-36.9{\pm}0.5^{\circ}C$, the depth of the eggs was $5.2-7.5{\pm}0.5cm$ as the distance of the average $6.4{\pm}0.5cm$. 29 eggs were scattered at least 0.2 cm interval. Artificial incubation of 29 eggs was conducted in artificial nest boxes in thermo-plastic composition of the incubator, and then incubated at $26.5-35.5{\pm}0.5^{\circ}C$, and an average constant temperature was $31.2-32.1{\pm}1.0^{\circ}C$. The incubation days ranged from 53 to 55. In case of most turtles, incubation at $31^{\circ}C$ (higher temperatures) generally produces all or mostly females, while incubation at $25^{\circ}C$(cooler temperatures) produces all or mostly males. Exceptionally, in case of genus Trionyx, the sex ratio of female : male of T. sinensis of a freshwater soft-shelled turtle was approximately 1:1, which differs from other genera of turtles and makes T. sinensis Strauch only turtles presently known to lack temperature-dependent sex determination.

• 한국환경생태학회지
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• 제22권1호
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• pp.59-65
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• 2008

본 연구는 2005년부터 2007년까지 파주, 강화도, 이천, 시화호, 충주 등 5개 지역에 서식하는 수리부엉이 9쌍의 둥지를 정기적으로 촬영, 관찰하여 번식생태와 교미행동을 연구하였다. 한배산란수는 $1\sim4$개로 평균 2.77개(n=15)였으며, 부화성공률은 약 71%(n=34)였고, 이소성공률은 약 83%(n=23)였다. 수리부엉이는 산란이 끝난 후에도 암수간의 교미행동이 지속되며, 새끼들이 둥지를 떠나는 시기인 부화 후 $7\sim8$주까지 교미행동을 계속한다는 것을 확인하였다. 이러한 수정 목적 이외의 교미 행동은 암컷과 수컷 모두의 필요에 의해서 이루어지는 것으로써 '부부관계(pair-bond)'의 확인, 유지, 강화를 통해 새끼를 안정적으로 키우기 위한 것으로 해석된다.

• Ocean and Polar Research
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• 제27권4호
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• pp.443-450
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• 2005

The ratio of breeding pairs of brown skuas (Catharacta lonnbergi), south polar skuas (C. maccormicki) and mixed species pairs between Barton and Weaver peninsulas remained the same $(X^2-test,\;X^2=0,503,\;df=2,\;p=0.778)$. The nests of skuas were clustered on Barton, whereas they were distributed randomly on the Weaver peninsula. The distance between brown skua nests, and that of mixed species pair nests were longer than those of south polar skua nests. Brown skua nests were distributed along the coast. Whereas, the nests of mixed species pairs and south polar skuas were found more frequently inland (Kruskal-Wallis, $X^2=11.631$, df=2, p<0.005). There was no interspecific difference in the distances between skua nests and Penguin rookery at Barton (Kruskal-Wallis, $X^2=2.153$, df=2, p=0.341) or at King Sejong Station (ANOVA, F=1.483, df=2, p=0.229). In general, skuas prefer lower locales (<125m above sea level) for their nest building sites. Brown skua nests were distributed mainly on the beach, whereas south polar skua were distributed on the predominant periglacial landforms and till areas $(X^2-test,\;X^2=24.988,\;df=8,\;p<0.005)$.

• 한국식품영양학회지
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• 제33권6호
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• pp.614-623
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• 2020

The objective of this study was to produce a nutrient delivery system (NDS) using sialic acid extracted from edible bird's nest (EBN), which improves brain function in patients with Alzheimer's disease and Parkinson's disease, by affinity bead technology (ABT). The inhibitory activity of acetylcholinesterase (AChE) and pyramidal cells in the dentate gyrus of the hippocampus were analyzed to investigate the effect of a sialic acid NDS on Alzheimer's disease. Also, the effect of a sialic acid NDS on Parkinson's disease was evaluated by rota-rod test and pole test in an animal model. Among the groups treated with donepezil, EBN, and sialic acid NDS, the AChE activity was the lowest in the sialic acid NDS-treated group. The results of the hippocampus analysis of the rat model confirmed that the sialic acid NDS inhibited amyloid-beta accumulation depending upon the concentration. Also, the sialic acid NDS group showed more improvement in motor deterioration than the1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced group in both the rota-rod test and pole test. Therefore, the sialic acid NDS had an effect of protecting not only Alzheimer's disease by inhibiting AChE and amyloid-beta accumulation, but Parkinson's disease by preventing neurotoxicity induced by MPTP.

• 한국환경생태학회지
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• 제23권6호
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• pp.528-534
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• 2009

국제적 멸종위기종이며, 동아시아에 국한하여 분포하는 섬개개비(Locustella pleskei)는 한국의 추자도, 마라도, 칠발도, 홍도 등에서 번식하는 것으로 알려져 왔으나, 구체적인 번식 정보는 아직 알려져 있지 않다. 본 연구는 마라도(N $33^{\circ}$ 06', E $126^{\circ}$ 16')에 번식하는 섬개개비의 번식 현황과 번식지 특성을 파악하기 위하여 실시되었다. 2008년 5월부터 9월까지 섬개개비 총 11쌍이 번식하는 것을 확인하였고, 번식하는 둥지는 곰솔숲의 관목층에 주로 분포하였다. 둥지는 곰솔숲의 관목층에 주로 분포하였으며, 동백나무(Camellia japonica)와 돈나무(Pittosporum tobira) 등 관목성 나무를 둥지목으로 선호하는 것으로 나타났다. 둥지목의 수고는 $2.77{\pm}1.10m$, 지면으로부터 둥지의 높이는 $1.75{\pm}0.56m$였으며, 둥지목의 수고는 다른 주변의 나무보다 낮은 것으로 나타나 마라도의 강한 해풍을 피하는데 유리한 것으로 판단되었다. 주로 억새잎이나 사초과 식물의 잎을 이용하여 밥그릇 형태의 둥지를 만들었으며, 둥지의 지름은 $11.9{\pm}0.5cm$, 높이는 $11.1{\pm}1.1cm$, 깊이는 $5.8{\pm}0.4cm$로 나타났으며, 산좌지름은 6.0cm였다. 마라도에서 섬개개비는 다른 섬지역보다 번식시기가 다소 늦었으며, 한배산란수는 3개로서 보통 다른 번식지의 4-5개보다 작았다. 이는 번식시기가 늦어질수록 한배산란수가 적어지는 일반적인 경향을 따르는 것으로 보인다. 이상의 결과로 볼 때, 마라도 곰솔숲의 솎아베기와 관목층 제거는 밀집된 관목층을 둥지로 선호하는 섬개개비의 번식에 영향을 미칠 수 있다. 따라서 섬개개비 번식 생태 및 서식지에 지속적이고 체계적인 조사가 요구되며, 숲가꾸기 수행에 있어서도 섬개개비의 보전을 위한 세심한 배려가 필요하다.