• Journal of Embryo Transfer
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• v.21 no.1
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• pp.35-43
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• 2006

Ions play important roles in various cellular processes including fertilization and differentiation. However, it is little known whether how ions are regulated during early embryonic development in mammalian animals. In this study, we examined changes in $Ca^{2+}\;and\;K^+$ concentrations in embryos and oviduct during mouse early embryonic development using patch clamp technique and confocal laser scanning microscopy. The intracellular calcium concentration in each stage embryos did not markedly change. At 56h afier hCG injection when 8-cell embryos could be Isolated from oviduct, $K^+$ concentration in oviduct increased by 26% compared with that at 14h after injection of hCG During early embryonic development, membrane potential was depolarized (from -38 mV to -16 mV), and $Ca^{2+}$ currents decreased, indicating that some $K^+$ channel might control membrane potential in oocytes. To record the changes in membrane potential induced by influx of $Ca^{2+}$ in mouse oocytes, we applied 5 mM $Ca^{2+}$ to the bath solution. The membrane potential transiently hyperpolarized and then recovered. In order to classify $K^+$ channels that cause hyperpolarization, we first applied TEA and apamin, general $K^+$ channel blockers, to the bath solution. Interestingly, the hyperpolarization of membrane potential still appeared in oocytes pretreated with TEA and apamin. This result suggest that the $K^+$ channel that induces hyperpolarization could belong to another $K^+$ channel such as two-pore domain $K^+(K_{2P})$channel that a.e insensitive to TEA and apamin. From these results, we suggest that the changes in $Ca^{2+}\;and\;K^+$ concentrations play a critical role in cell proliferation, differentiation and reproduction as well as early embryonic development, and $K_{2P}$ channels could be involved in regulation of membrane potential in ovulated oocytes.

• Journal of Environmental Impact Assessment
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• v.25 no.5
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• pp.319-332
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• 2016

Alien turtles belonging to Genus Trachemys have been designated as Invasive Alien Species since 2001 and their import has been banned in Korea. However, current status of import and distribution of the other alien turtles have not been reported. In this study, we aimed to investigate the taxa of alien turtles introduced into Korea, to assess their potential risks to the natural ecosystems and to suggest the future management directions of them in Korea. We identified 73 species of alien turtles belonging to 9 families. Since 2008, more than 6,000 kg of turtles have been imported annually and widely distributed through the pet shops, traditional markets and individual transactions. From the survey of natural habitats, we found that 8 species belonging to 3 families including Chrysemys picta, Pseudemys concinna, P. nelsoni, P. peninsularis, P. rubriventris, Mauremys sinensis, Macrochelys temminckii and Trachemys scripta have inhabited in 12 study sites. Out of 73 alien turtles, the potential adverse impacts of 13 species to ecosystems are serious when we considered status of designation of invasive alien species in other countries. For the management of alien turtles, it is required to register alien turtles in the import list and share general information such as import purpose, distribution and management condition among relevant authorities. The breeders and distributors must be obliged to identify turtles and to record management. The government must check transfer and migration of turtles periodically to prevent their introduction and spread into natural environments. The change of alien turtle populations in natural habitats should be monitored and their management plan should be developed to control the alien turtles in areas where the impacts are significant.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.58-69
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• 2018

The purpose of this study was to present specific standards for landscape planning and construction applicable to landscaping areas in various historical sites. The results are as follows: First, the types of historical sites are classified according to their preservation status and processing techniques, and the classification according to their status is divided into those that have been buried underground, such as those that have been exposed to the ground, such as buildings and structures, and those that have a reputation or a record of the sites. The classification according to the wartime processing technique was classified by such techniques as closures that isolate the site, penetration that can be seen on the site, and overlays where a separate protection facility is installed on the site. Second, the principles of landscape planning for display of historical sites are divided into the items that make up the historical site, surface treatment of the sites, tree planting, and installation of facilities. If the site is not a circular space, the area separating the space by different materials between the components is required. In the event that preservation of the historical site is required, it is deemed desirable to use the soil, and to do so, the use of grasses and shrubs is effectively considered to be effective. The introduction of plants and plants should be considered according to the nature of the space. Depending on the area and nature of the monument, the facility is required to take a cautious approach by reviewing its influence on the landscape and the additional excavation of the monument. Third, the readjustment method derived as a result of looking at the landscaping principle in the historical site space was classified as conservation of status, installation of protection facilities, burial, restoration, relocation, and reproduction. Preservation of the status quo is essential for limited landscape planning and should not affect the prototype of existing relics. The protection facility shall be installed where necessary to protect the relics, and when the soil is formed, the surface treatment shall be required to remove trees that could damage the site and prevent soil and soil oil from being lost after the site. The restoration shall establish a landscaping plan according to the circular preservation based on the clues to the circle. The transfer requires a landscaping plan to create an environment similar to the outer space of an existing site and should be able to highlight the value or location of the original site. The reenactment should have a landscaping plan to revive the landscape and atmosphere of the past for the now-defunct remains. Fourth, landscaping can simultaneously satisfy the preservation of excavation sites and the increase in exhibition effects. In order to protect the traces of the past and vitalize the site of the ruins today, specific measures are required, the creation of a park for historical sites that preserve the functions and value of the relics, and the formation of a shape of linked contents can be suggested as alternatives.

• (The) Research of the performance art and culture
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• no.39
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• pp.415-455
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• 2019

This paper aimed to clarify the identity and category of the Jeong Jeongnyeol-je Chunhyangga from the perspective of the pansori transfer, while revealing the trajectory of Jeong Jeong-ryeol-je Chunhyangga, which remains in the modern pansori. Jeong Jeong-ryeol's Chunhyangga pansori part has been handed out to date, and except for the love song section, the pansori section, which corresponds to the love-separate-suffering-reunion paragraph, is almost complete. In the case of "Lee Doryeong enters Dongheon," "Hwangneungmyo song," and "The royal secret inspector visits Chunhyang's house to console her", there is a difference in pansori rhythm compared to Chunhyangga, which is currently held. "Why Yi Doryeong came to Chunhyang's House" is used in the form of an Aniri in the current Chunhyangga and "Chunhyang is treated as a virtuous woman in Namwon" is the only one included in Park Rokju's Changbon. "The royal secret inspector gathers people of Namwon to give a feast" is a new part that is not found in Chunhyangga, which is now being held, and can be seen as the Changgeuk sori of pursuing theatrical fun. On the other hand, this paper confirmed that the period between 1936 and 1937, when the Joseon Traditional Vocal Music Group actively performed Changgeuk and the record companies released a series of Changgeuk records, such as and , was an important time for the re-establishment of the Jeong Jeong-ryeol-je Chunhyangga, and that the Chunhyangga of those who had learned it before 1936-1937 was different from those who had learned it after that period. The preceding group includes Park Rok-ju, Kim Yeo-ran and Kim So-hee, while the latter group includes Kim Yeon-soo, Jung Kwang-soo, Park Dong-jin, Jung Kwang-soo and Kang Do-geun. In addition, except for Kim So-hee, these two groups are divided by the time they have learned Jeong Jeong-ryeol-je, whether they inherit the Jeong Jeong-ryeol-je from beginning to end, and by the gender of male and female singers. In teaching his pupils, Jeong Jeong-ryeol chose to use the "old-fashioned pansori" teaching method with impromptu plate-making in mind and the "modern pansori" teaching method with stereotyped sounds in mind. As a result, there were two aspects of Jeong Jeongryeol-je Chunhyangga's succession: a female singer-centered succession, which was held as learned from beginning to end, and a male singer-centered succession, which was held differently depending on the pansori schools or versions.