• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.282-290
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• 1997

Hepatocytes of Anguilla japonica have been prepared using a collagenase perfusion technique. The isolated cells attached efficiently to fibronectin-coated culture dishes and subsequently formed monolayers in serum-free medium. These cultures maintained in appropriate medium at least for 10 days with minimal cell loss. The effects of estradiol and pituitary hormones on vitellogenin (Vg) synthesis were examined in primary hepatocyte culture of the immature eels. In fish, as in other oviparous vertebrates, estrogen is a major inducer of Vg synthesis. However, $estradiol-17\beta(E_2)$ alone was insufficient to induce Vg synthesis in cultures of eel hepatocytes. Combination of $E_2$ with growth hormone (GH) and/or prolactin (PRL) markedly stimulated Vg synthesis. Even in cultures exposed to $E_2$ or precultured without hormones for 8 days, $E_2$ alone could not fully induce Vg synthesis. The synthesis of Vg was dramatically increased when hepatocytes were cultured in medium supplemented with $E_{2}+GH+PRL$ for 6 days. At this point, even though GH and/or PRL were eliminated from the medium, Vg synthesis was not influenced by these factors during culture of further 3 days. These results indicate that pituitary hormones, in particular GH and PRL, play important roles in the regulation of Vg synthesis in primary cultures of eel hepatocytes.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.3
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• pp.263-272
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• 2012

Carbon dioxide, emitted by human activities since the industrial revolution, is regarded as a major contributor of global warming. There are many efforts to mitigate climate change, and carbon dioxide capture and geological storage (CCS) is recognized as one of key technologies because it can reduce carbon dioxide emissions from large point sources such as a power station or other industrial installation. The inclusion of CCS as clean development mechanism (CDM) project activities has been considered at UNFCCC as financial incentive mechanisms for those developing countries that may wish to deploy the CCS. Although the Conference of the Parties serving as the Meeting of the Parties to the UNFCCC's Kyoto Protocol (CMP), at Cancun in December 2010, decided that CCS is eligible as CDM project activities, the issues identified in decision 2/CMP.5 should be addressed and resolved in a satisfactory manner. Major issues regarding modalities and procedure are 1) Site selection, 2) Monitoring, 3) Modeling, 4) Boundaries, 5) Seepage Measuring and Accounting, 6) Trans-Boundary Effects, 7) Accounting of Associated Project Emissions (Leakage), 8) Risk and Safety Assessment, and 9) Liability Under the CDM Scheme. The CMP, by its decision 7/CMP.6, invited Parties to submit their views to the secretariat of Subsidiary Body for Scientific and Technological Advice (SBSTA), SBSTA prepared a draft modalities and procedure by exchanging views of Parties through workshop held in Abu Dhabi, UAE (September 2011). The 7th CMP (Durban, December 2011) finally adopted the modalities and procedures for CCS as CDM project activities (CMP[2011], Decision-/CMP.7). The inclusion of CCS as CDM project activities means that CCS is officially accredited as one of $CO_2$ reducing technologies in global carbon market. Consequently, it will affect relevant technologies and industry as well as law and policy in Korea and aboard countries. This paper presents a progress made on discussion and challenges regarding the issue, and aims to suggest some considerations to policy makers in Korea in order to demonstrate and deploy the CCS project in the near future. According to the adopted modalities and procedures for CCS as CDM project activities, it is possible to implement relevant CCS projects in Non-Annex I countries, including Korea, as long as legal and regulatory frameworks are established. Though Korea enacted 'Framework Act on Low Carbon, Green Growth', the details are too inadequate to content the requirements of modalities and procedures for CCS as CDM project. Therefore, it is required not only to amend the existing laws related with capture, transport, and storage of $CO_2$ for paving the way of an prompt deployment of CCS CDM activities in Korea as a short-term approach, but also to establish the united framework as a long-term approach.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.14-14
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• 2011

W (tungsten)-alloys will be the most promising plasma facing armor materials in highly loaded plasma interactive components of the next step fusion reactors due to its high melting point, high sputtering resistance and low deuterium/tritium retention. The bonding technology of tungsten to Cu alloy was one of the key issues. In this paper, W/CuCrZr diffusion bonding has been performed successfully by inserting pure metal interlay. The joint microstructure, interfacial elements migration and phase composition were analyzed by SEM, EDS, XRD, and the joint shear strength and micro-hardness were investigated. The mock-ups were fabricated successfully with diffusion bonding and the cladding technology respectively, and the high heat flux test and thermal fatigue test were carried out under actively cooling condition. When Ni foil was used for the bonding of tungsten to CuCrZr, two reaction layers, Ni4W and Ni(W) layer, appeared between the tungsten and Ni interlayer with the optimized condition. Even though Ni4W is hard and brittle, and the strength of the joint was oppositely increased (217 MPa) due primarily to extremely small thicknesses (2~3 ${\mu}m$). When Ti foil was selected as the interlayer, the Ti foil diffused quickly with Cu and was transformed into liquid phase at $1,000^{\circ}C$. Almost all of the liquid was extruded out of the interface zone under bonding pressure, and an extremely thin residual layer (1~2 ${\mu}m$) of the liquid phase was retained between the tungsten and CuCrZr, which shear strength exceeded 160 MPa. When Ni/Ti/Ni multiple interlayers were used for bonding of tungsten to CuCrZr, a large number of intermetallic compound ($Ni_4W/NiTi_2/NiTi/Ni_3T$) were formed for the interdiffusion among W, Ni and Ti. Therefore, the shear strength of the joint was low and just about 85 MPa. The residual stresses in the clad samples with flat, arc, rectangle and trapezoid interface were estimated by Finite Element Analysis. The simulation results show that the flat clad sample was subjected maximum residual stress at the edge of the interface, which could be cracked at the edge and propagated along the interface. As for the rectangle and trapezoid interface, the residual stresses of the interface were lower than that of the flat interface, and the interface of the arc clad sample have lowest residual stress and all of the residual stress with arc interface were divided into different grooved zones, so the probabilities of cracking and propagation were lower than other interfaces. The residual stresses of the mock-ups under high heat flux of 10 $MW/m^2$ were estimated by Finite Element Analysis. The tungsten of the flat interfaces was subjected to tensile stresses (positive $S_x$), and the CuCrZr was subjected to compressive stresses (negative $S_x$). If the interface have a little microcrack, the tungsten of joint was more liable to propagate than the CuCrZr due to the brittle of the tungsten. However, when the flat interface was substituted by arc interfaces, the periodical residual stresses in the joining region were either released or formed a stress field prohibiting the growth or nucleation of the interfacial cracks. Thermal fatigue tests were performed on the mock-ups of flat and arc interface under the heat flux of 10 $MW/m^2$ with the cooling water velocity of 10 m/s. After thermal cycle experiments, a large number of microcracks appeared at the tungsten substrate due to large radial tensile stress on the flat mock-up. The defects would largely affect the heat transfer capability and the structure reliability of the mock-up. As for the arc mock-up, even though some microcracks were found at the interface of the regions, all microcracks with arc interface were divided into different arc-grooved zones, so the propagation of microcracks is difficult.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.238-245
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• 1998

The reasonable level of nitrogen fertilizer is a key factor to reduce environmental contamination as well as to increase crop yield and quality. The treatments are $N=42kg\;10a^{-1}$, $N=48kg\;10a^{-1}$, $N=54kg\;10a^{-1}$. $N=60kg\;10a^{-1}$. $N=72kg\;10a^{-1}$ and $N=150kg\;10a^{-1}$. Analytical results of yield and quality of tea leaves harvested the second time are summarized as follows: The soil of experimental field was higher in organic matter($49.9g\;kg^{-1}$) and available phosphate($937mg\;kg^{-1}$) compared to the general field but lower in pH(5.07) compared to the general field. When the amount of nitrogen fertilizer application was raised, the yield of tea leaves, the content of nitrogen, total free amino acids, caffeine and chlorophyll increased: however, the yield of tea leaves increased to excessive levels. On the other hand, the increased level of nitrogen fertilizer did not show any difference in the contents of vitamin C and tannin. Eleven kinds of amino acids were isolated from second harvested leaves of tea where the content of theanine occupied over 50%, and content of $665{\sim}763mg\;100g^{-1}$. The contents of fatty acids and catechin did not show correlation with application level of nitrogen fertilizer. The content of fatty acid was produced $1,742{\sim}2,643mg\;100g^{-1}$, and content of catechin was produced 12.47~13.54%. In scoring test, $N=60kg\;10a^{-1}$ treatment was 0.5~6.0 point higher compared to other treatments. Consequently, $N=60kg\;10a^{-1}$ is considered to be the best level of nitrogen fertilizer in terms of decreased environmental contamination as well as to increase crop yield and quality.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.334-344
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• 2020

A total of 24 families, 44 species, and 658 benthic macroinvertebrates were identified, and Ecdyonurus dracon Kluge (13%) was the dominant species in forested streams within the Yeonyeopsan (Mt.). A total of four habit categories (i.e., clingers (56%), burrowers (19%), swimmers (14%), and sprawlers (56%)) were identified, and clingers were the dominant habit at all survey points except point one (UP1). Habitat characteristics were depended on the hydraulic factors (e.g., flow velocity, depth, and substrates), water quality (e.g., DO and water temperature), and the habitat characteristics were differed in the riffle, which has a faster the flow velocity, compared by in the stagnant pool. In other words, in riffles, the clingers dominated in high flow velocity with the large maximum and median grain size for substrates in the habitats regardless of depth, but the burrowers and sprawlers were dominant in low flow velocity with the small maximum and median grain size for substrates in the habitats. Moreover, DO and flow velocity were in positive correlation (y = 0.6666x - 0.659, R² = 0.0851), and the habitat for burrowers was wider than that for sprawlers or clingers. The water depth was negatively correlated with water temperature (y = -26.397x + 283.87, R² = 0.1802) since the water temperature is more sensitive to insolation in shallow depth. pH was positively correlated with water temperature. The investigation of the habitat characteristics by separating the relations between pH and DO in upstream and downstream showed the low pH and high DO in the upstream with a high crown density of 68%, regardless of community composition. On the other hand, high pH and low DO in the downstream with a relatively low crown density of 51%. It was considered that the riparian forest played a role in suppressing the growth of attached algae and the controlling water temperature in headwater streams. Our findings identified the habitat characteristics of benthic macroinvertebrates in a headwater stream. We expected that the finding can provide reference data for suggesting conservation and management plans in a headwater stream and increasing academic value.

• The Korean Journal of Air & Space Law and Policy
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• v.2
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• pp.31-67
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• 1990

One of the first issues which arose in the evolution of air law was the determination of the vertical limits of airspace over private property. In 1959 the UN in its Ad Hoc Committee on the Peaceful Uses of Outer Space, started to give attention to the question of the meaning of the term "outer space". Discussions in the United Nations regarding the delimitation issue were often divided between those in favour of a functional approach ("functionalists"), and those seeking the delineation of a boundary ("spatialists"). The functionalists, backed initially by both major space powers, which viewed any boundary as possibly restricting their access to space(Whether for peaceful or military purposes), won the first rounds, starting with the 1959 Report of the Ad Hoc Committee on the Peaceful Uses of Outer Space which did not consider that the topic called for priority consideration. In 1966, however, the spatialists, were able to place the issue on the agenda of the Outer Sapce Committee pursuant to Resolution 2222 (xxx1). However, the spatialists were not able to present a common position since there existed a variety of propositions for delineation of a boundary. Over the years, the funtionalists have seemed to be losing ground. As the element of location is a decisive factor for the choice of the legal regime to be applied, a purely functional approach to the regulation of activities in the space above the Earth does not offer a solution. It is therefore to be welcomed that there is clear evidence of a growing recognition of the defect inherent to such an approach and that a spatial approach to the problem is gaining support both by a growing number of States as well as by publicists. The search for a solution of the problem of demarcating the two different legal regimes governing the space above the Earth has undoubtedly been facilitated, and a number of countries, among them Argentina, Belgium, France, Italy and Mexico have already advocated the acceptance of the lower boundary of outer space at a height of 100km. The adoption of the principle of sovereignty at that height does not mean that States would not be allowed to take protective measures against space activities above that height which constitute a threat to their security. A parallel can be drawn with the defence of the State's security on the high seas. Measures taken by States in their own protection on the high seas outside the territorial waters-provided that they are proportionate to the danger-are not considered to infringe the principle of international law. The most important issue in this context relates to the problem of a right of passage for space craft through foreign air space in order to reach outer space. In the reports to former ILA Conferences an explanation was given of the reasons why no customary rule of freedom of passage for aircraft through foreign territorial air space could as yet be said to exist. It was suggested, however, that though the essential elements for the creation of a rule of customary international law allowing such passage were still lacking, developments apperaed to point to a steady growth of a feeling of necessity for such a rule. A definite treaty solution of the demarcation problem would require further study which should be carried out by the UN Outer Space Committee in close co-operation with other interested international organizations, including ICAO. If a limit between air space and outer space were established, air space would automatically come under the regime of the Chicago Convention alone. The use of the word "recognize" in Art. I of chicago convention is an acknowledgement of sovereignty over airspace existing as a general principle of law, the binding force of which exists independently of the Convention. Further it is important to note that the Aricle recognizes this sovereignty, as existing for every state, holding it immaterial whether the state is or is not a contracting state. The functional criteria having been created by reference to either the nature of activity or the nature of the space object, the next hurdle would be to provide methods of verification. With regard to the question of international verification the establishment of an International Satelite Monitoring Agency is required. The path towards the successful delimitation of outer space from territorial space is doubtless narrow and stony but the establishment of a precise legal framework, consonant with the basic principles of international law, for the future activities of states in outer space will, it is still believed, remove a source of potentially dangerous conflicts between states, and furthermore afford some safeguard of the rights and interests of non-space powers which otherwise are likely to be eroded by incipient customs based on at present almost complete freedom of action of the space powers.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.1
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• pp.33-62
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• 2020

The current air transportation industry is facing a lot of changes not only in the quantitative growth of the market, but also in the legal aspects. For many years, the Warsaw Convention has contributed to the uniform discipline of civil carriers' legal liabilities arising from international aviation accident and has fulfilled the duties of legal guardians for the development of the air transport industry. In the process, however, the consumer interests of the air transport industry did not have much protection compared to other industries. In response, the Montreal Convention has effected for protecting the interests of aviation consumers, and there are numerous legal changes around the world to protect aviation consumers like passengers. The mental damages of airline passengers arising from the accident can also be understood as part of the protection of air consumers. Considering that the US Federal Court has dealt with the recognition of mental damages for air passengers since the early 1990s. However, Korean judicial precedent still excludes mental anguishes from the scope of damage compensation. From this point of view, it is considered academically meaningful to analyze the latest case of the US federal court. Recently, the United States Court of Appeal for the Sixth Circuit in Doe v Etihad Airways applied a different interpretation against the traditional opinion: passengers could not recover for mental distress unless that mental distress resulted from a bodily injury sustained in an airplane accident. The background of the court's conclusions can be explained in many ways, among other things, unlike the Warsaw Convention the new international rule, Montreal Convention is recognizing the importance of ensuring protection of the interests of consumers in international carriage by air and the need for equitable compensation based on the principle of restitution.

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.251-257
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• 2006

Purpose : In this study, we created a questionnaire and collected answers concerning actual conditions of vaccination and parents' knowledge of vaccination issues, in order to find false knowledge of patients. We tried to give correct information and suggested the role of the pediatrician. Methods : We made questionnaires and collected answers from 466 parents from March 2004 to June 2004. Results : Places of vaccination were pediatric clinics(49.4 percent), health centers(27.7 percent), general/university hospitals(15.0 percent) and other clinics(4.9 percent). We found 38.8 percent of parents thought that the reason for vaccination at pediatric clinics was a belief of speciality, even though there is no difference in the vaccination itself. We also found 15.0 percent of parents thought that there were no differences between pediatricians and other physicians, but 52.0 percent of parents wanted to receive vaccination at pediatric clinics in the future. Our study also found that 62.4 percent of parents wanted to make out a preliminary questionnaire for vaccination. Many parents got vaccination information from vaccination record books(57.9 percent), and 52.6 percent of parents incorrectly believed that Hib vaccination could prevent all kinds of meningitis. Conclusion : Our study suggests that pediatricians need to make efforts to give out correct information. It is necessary to use preliminary questionnaires for vaccination and correct vaccination information should be written on the vaccination record book. Also, there needs to be counselling with parents about weaning, growth and development at the time of vaccination, and to point out the differences between pediatricians and other physicians.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.4
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• pp.113-122
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• 2012

A success of opening a business should be supported with complete preparations and implementation. While there have been various educational programs for opening a business to support its success, there have not been a lot of studies on the relationships between educational programs and operational performance in small businesses, due to the difficulties of empirical survey. In this point, this study attempts to understand the relationships between preparation of opening a business and operational performance, while dividing samples into two groups (1. a group completing educational programs for opening a business, 2. a group non-completing). For the perspectives of the preparation of opening a business, various success factors have been suggested through various studies, but the perspectives and approaches of balanced business operation have been required. Therefore, using BSC, it developed a framework with the four perspectives of preparation for opening a business, and empirically reviewed the relationships between the four perspectives and operational performances in small businesses. It conducted a survey on the total 252 samples, whose business periods are less than 5 years. As the results, the preparations of financial and customer/marketing perspectives have significant relationships between operational performances in total samples, preparations of financial, customer/marketing, and growth-strategies perspectives in the educational program completing group and only preparation of financial perspectives in the non-completing group have significant relationship with operational performances. The differences between the two groups may imply that educational programs for opening a business may be helpful for preparation of opening a business and have some possibility of direct and indirect effects for the success of opening a business. Also, the developed BSC based-preparation framework for opening a business is meaningful for the view of balanced business operations, and can contribute to develop the educational programs for opening a business.

• Journal of Life Science
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• v.22 no.1
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• pp.16-24
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• 2012

Polyamines are essential for cell growth and differentiation; however their precise roles are unclear yet. In the present study, the cytotoxic effect of spermine (spm) on MCF-7 cells was investigated. In the MTT assay of MCF-7 cells treated with spm, cell viability was significantly decreased in a time-and dose-dependent manner. Cell viability measurement was confirmed by trypan blue staining. FACS analysis shows that sub-G1 was increased in a time-and dose-dependent manner too. When the cells were treated with spm, cells started to show morphological changes within 2 hrs. The expression of adhesion proteins (FAK and integrin ${\beta}1$), and cytoskeletal protein (actin) was checked by Western blotting analysis. Integrin ${\beta}1$ levels were slightly decreased, and FAK and actin levels were rapidly decreased with spm treatment. In confocal laser scanning microscopy, the distribution of actin did not change but the expression decreased in a dose-dependent manner with spm treatment. FAK was evenly distributed under the plasma membrane in the untreated control. However, at 10 ${\mu}M$ spm FAK seemed to move toward the cell nucleus. Integrin ${\beta}1$, which was mainly found in the focal point of the plasma membrane in the untreated control, dispersed through the entire plasma membrane in spm treatment. The present results indicate that cytotoxic effects of spm are triggered by the disruption of adhesion proteins and cytoskeletal protein.