• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.281-285
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• 1979

A species of enigmatic amoeba was found front the oysters culcured in Jinhae Bay and the Goje Bay in September-October 1978 and October 1979. Occurrence and the morphological characteristics of the amoeba were studied. Based on their peculiar morphological characters the enigmatic body was a species of parasitic amoeba. The amoebas were morphologically very similar to the amoeboid parasite described by Sawyer(1977). Occurrence of the oysters infected with the amoeboid ranged from zero to $13.3\%$. The infection rate did not show any relations to the depth of water where the oysters were suspended. The longest diameter of the amoeba is $24\;\mu$. The thin outer membrane is lightly stained with eosin and PAS positively. Initially one amoeboid was found in an ovum, and later it propagated to 3 to 4 individuals.

• The Korean Journal of Ecology
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• v.12 no.1
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• pp.37-49
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• 1989

When the light stimulus was presented continuously, habituations were formed, after 13 and 14 hrs in amoeba and planaria, repectively. As amoeba more habituated, the light-escaping velocity of streaming was decreased with a negative-exponential function. in two-dimensional electrophoretic patterns of proteins of amoeba habituated, a newly synthesized protein (pI 7.0, MW 20 kD) was detected. Therefore, it is conjectured that similarity or commonality may exist between amoeba and planaria habituations to light, and in these behavioral modifications, specific protein(s) may be involved in molecular level.

• Journal of the Korean Geographical Society
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• v.45 no.4
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• pp.502-520
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• 2010

The main objective of the paper is to develop a GIS-based method for delineating spatial clusters. Major tasks are: (i) to devise a sustainable algorithm with reference to various methods developed in the fields of geographic boundary analysis and cluster detection; (ii) to develop a GIS-based program to implement the algorithm. The main results are as follows. First, it is recognized that the AMOEBA technique utilizing LISA is the best candidate. Second, a modified version of the AMOEBA technique is proposed and implemented in a GIS environment. Third, the validity and usefulness of the modified AMOEBA algorithm is assured by its applications to test and real data sets.

• The Korean Journal of Zoology
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• v.28 no.1
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• pp.21-30
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• 1985

By two-dimensional gel electrophoresis loss of a cell-specific protein was detected in tD strain of Amoeba proteus that had been infected by symbiotic bacteria extracted from xD strain. In 50 days of experimental infection by induced phagocytosis the host amoeba lost the ability to synthesize the tD cell-specific protein even after removal of the infective bacteria and xD cell-specific protein by growing the amoebae at $27^\\circC$. By this time the host amoebae were obligately dependent on the bacteria. From these and other results (Lorch and Jeon, Science 221:549), it is clear that the incompatibility of the infected nuclei with the cytoplasm of the uninfected amoeba and the obligate dependence of the host on bacteria are due to the irreversible inactivation or the loss of the cell-specific gene by bacterial infection in this amoeba.

• Animal Systematics, Evolution and Diversity
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• v.32 no.1
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• pp.1-8
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• 2016

Vermamoeba vermiformis is a very important free-living amoeba for human health in association with Legionnaires' disease and keratitis. This interesting amoeba was firstly isolated from a freshwater of Dokdo (island), which was historically used for drinking water. Trophozoites and cyst forms of V. vermiformis strain MG1 are very similar to previous reported species. Trophozoites of V. vermiformis strain MG1 showed cylindrical shape with prominent anterior hyaline region. The average ratio of length and width was about 6.5. Typically, cysts of the strain MG1 showed a spherical or slightly ovoidal shape with smooth wall, and lacked cyst pores. Some cysts had crenulate-walled ectocyst, which was separated from endocyst wall. Further, 18S rRNA gene sequence of V. vermiformis strain MG1 showed very high similarity to other V. vermiformis species (99.4%-99.9% identity). Molecular phylogenetic analysis based on 18S rRNA gene sequences clearly confirmed that the isolate was one strain of V. vermiformis with maximum bootstrap value (maximum likelihood: 100%) and Bayesian posterior probability of 1. Thus, the freshwater of Dokdo in Korea could harbor potentially pathogenic amoeba that may cause diseases in humans.

• Journal of Environmental Science International
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• v.17 no.10
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• pp.1121-1127
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• 2008

The free-living amoeba and Acanthamoeba sp. are widely distributed in fresh water, soil, air and dust in the world. We studied distribution of amoeba from low Nakdong River(Mulgum and Maeri) and removal efficiency in water treatment process of Busan metropolitan city. During this investigation, water quality showed pH $7.4{\sim}9.6({\pm}1.1)$, water temperature $2.0{\sim}29.0({\pm}17)^{\circ}C$, turbidity $4.8{\sim}27.4({\pm}11.0)$ NTU, chlorophyll-a $10.3{\sim}109.0({\pm}44.3)\;mg/m^{3}$, BOD $1.7\sim4.9({\pm}2.6)$ mg/L, COD $3.1\sim-6.9({\pm}5.0)$ mg/L and total coliform $17\sim920({\pm}200.5)$ MPN/100 mL. The free-living amoeba were detected highly than Acanthamoeba sp., 11 out of 22 in raw water samples were positive (50%) for Acanthamoeba sp. from February 2005 to December 2005. The seasonal characteristics of tree-living amoeba and Acanthamoeba sp. in raw water were mainly distributed through the spring to the early fall. When tree-living amoeba and Acanthamoeba sp. were passed through the water treatment of pilot-plant, approximately 80% was sure to be removed through pre-ozonation, sedimentation, send filtration. 100% was removed after post-ozonation process. All of the isolated amoebas from Nakdong River were Acanthamoeba sp. AC311 18S ribosomal RNA gene with 98% nucleotide sequence homology.

• Korean Journal of Remote Sensing
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• v.27 no.5
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• pp.601-611
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• 2011

Land cover changes are occurring for a variety of reasons such as urbanization, infrastructure construction, desertification, drought, flood, and so on. Many researchers have studied the cause and effect of land cover changes, and also the methods for change detection. However, most of the detection methods are based on the dichotomy of "change" and "not change" according a threshold value. In this paper, we present a change detection method with the integration of probability, spatial autocorrelation, and hotspot detection. We used the AMOEBA (A Multidirectional Ecotope-Based Algorithm) and developed the AMOEBA-CH (core hotspot) because the original algorithm tends to produce too many clusters. Our method considers the probability of land cover changes and the spatial interactions between each pixel and its neighboring pixels using a local spatial autocorrelation measure. The core hotspots of land cover changes can be delineated by a contiguity-dominance model of our AMOEBA-CH method. We tested our algorithm in a simulation for land cover changes using NDVI (Normalized Difference Vegetation Index) data in South Korea between 2000 and 2008.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.101-111
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• 1991

Amoeba sp. was cultured under the light and the dark conditions, and the activity of phosphatases was investigated. There was a linear correlation between the early reaction time and the activity of phosphatases when phosphatases were incubated at 30℃. Then the activity of acid phosphatase was about 2 times higher than that of alkaline phosphatase. The activity of phosphatase was optimal at pH 5.0 in acidic part and at pH 8.0 in alkaline part, respectively. The optimal temperature of phosphatases was near the 40℃. The isozyme patterns of cytoplasmic acid phosphatase were compared with those of membraneous one. Both the isozyme patterns were shown to bo polymorphic on the polyacyamide gel, but different band patterns were observed in the isozymes of the cytoplasmic and the membraneous acid phosphatases. The number of Amoeba sp. under the light stimulus for 48 hours decreased negative exponentially from the illumination. The activity of acid and alkaline phosphatases under the illumination of light incresed 1.7 and 1.5 times higher, respectively, than the activity of those under the dark condition. This result apperars to be related to the mechanism of the autophosphorylation.

• The Korean Journal of Zoology
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• v.34 no.1
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• pp.44-53
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• 1991

Distribution of the antigens during the cell cycle of amoebae was followed by immunof-luorescence microscopy using a monoclonal antibody against the nucleus as a probe. While the cells were in the interphase, the antigen was localized on the nucleus membrane. But it was dispersed all over the cytoplasm during mitosis and cytokinesis. The molecular weights of the immunoreacted antigens were 210 KD and 190 KD as determined by SDS PAGE and western blotting of the purified nuclei. The antigens were not soluble in non-ionic detergent, but were released from the nucleus by incubation with 0.05 M sodium carbonate, pH 10.6 or with 8 M urea at serial chemical extraction. Thus the antigens appeared to be peripheral proteins of the nurBeus envelope. The isoelectic point of both antigens was 7.64 as determined by 2 D PAGE and transfer blotting. Considering the peiipherd association with the nucleus membrane and the dispersed distribution during mitosis, the antigens could be lamin like proteins. Hourever, it appears also possible that they are the component molecules of the unusually structured aurous lamina of amoeba nucleus since they have the large molecular weight and the basic pl.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.215-218
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• 2009

In this paper, there analyzed the UV behavior and detection images due to corona discharge of insulators at 22.9kV. As the results, the shapes of UV detection images are jellyfish, sunflower, and amoeba type. Generally, the jellyfish and sunflower type appeared in air discharge. In surface discharge, Amoeba is generated. Also, there are classified 8 patterns such as sunflower A or B, jellyfish A or B, amoeba A, B, C, D. This method of the facilities assessment has an immediate effect in the field.