• 한국식품과학회지
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• 제22권2호
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• pp.172-176
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• 1990

크릴에 과량 존재하는 불소를 감량시키고자 전기분해 반응에 의한 electrocondensation 방법을 이용하였다. Electrotocondensation 방법에 의한 크릴 불소의 감량정도는 불소이온의 존재형태 (이온 및 결합상태의 불소, 총불소)와 시료의 부위(육질, 키틴질, 건조크릴)에 따라 차이가 있는 것으로 나타났다. 전기분해 반응시간에 따른 불소의 감량곡선을 살펴보면, 반응초기에는 불소의 감량이 빠르게 진행되었으나 일정시간 이후부터는 서서히 감량되는 경향을 나타내어 전기분해반응 120분 후에는 반응전 초기 불소농도의 $30{\sim}70%$ 수준까지 감량시킬 수 있었다. 이상의 결과를 살펴볼 때, electrocondensation 방법으로 크릴에 과량 함유되어 있는 불소를 상당량 제거하였지만. 아직도 많은 양의 불소가 각 시료에 잔재하고 있어, 완전한 불소세거를 위해서는 보다 깊은 연구가 필요로 되는 것으로 생각되었다. 즉 Newman은 세포외 불소가 벼에 집적되는 과정에서 hydroxyl기와의 치환반응을 고찰하였고, Rehbein등은 크릴을 주 먹이사슬로 하는 남극어류의 대부분이 chitinase와 pretense등의 강한 효소활성으로 크릴을 소화하는 과정에서 불소가 유리되어 체외로 방출되는 것으로 고찰하고 있어, 불소의 이동기작 및 집적과정에 대한 깊은 연구와 더불어 electrocondensation 방법을 보다 효율적으로 이용할 수 있는 방안이 모색된다면 크릴의 불소문제는 완전히 해결될 수 있을 것으로 생각되었다.

• 수산해양기술연구
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• 제58권4호
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• pp.352-358
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• 2022

We explored the frequency response of krill target strength (TS) to understand the Antarctic krill (Euphausia superba) and ice krill (Euphausia crystallorophias) using the stochastic distorted-wave Born approximation (SDWBA) model. The results showed that the distribution of orientation and the fatness factor could significantly impact on the frequency response of TS. Krill TS is clearly depended on acoustic properties, which could affect to estimate the biomass of two krill species. The results provide insight into the importance of understanding TS variation to estimate the Antarctic krill and ice krill biomass, and their ecology related to the environmental features in the Southern Ocean.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.215-219
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• 2007

Long-tenn variation in krill (Euphausia superba) and salp (mainly Salpa thompsoni) stocks was compared to environmental changes in the Atlantic and Indian sectors of the Antarctic. Environmental conditions examined were air temperature, water temperature, salinity, and sea-ice extent from 1926 to 1938 and from 1982 to 2000. The long-term pattern of krill was opposite to that of salp: krill stock decreased while salp stock increased concurrently. Krill stock was about three-fold higher from 1926 to 1938 than from 1982 to 2000, but salp was about four -fold lower in 1926-1938 than in 1982-2000. A wanning trend was observed in the environmental data, and the long-term variation in krill and salp stocks was affected by this trend.

• Ocean and Polar Research
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• 제25권4호
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• pp.617-623
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• 2003

Organisms living in the Arctic and Antarctic regions are exposed to strong constraints, of which temperature is a driving factor. Evolution has led to special adaptations, some with important implications at the biochemical, physiological, and molecular levels. The northern and southern polar oceans have very different characteristics. Tectonic and oceanographic events have played a key role in delimiting the two polar ecosystems and influencing evolution. Antarctica has been isolated and cold longer than the Arctic; its ice sheet developed at least 10 million years earlier. As an intermediate system, the Arctic is a connection between the more extreme, simpler Antarctic system and the very complex temperate and tropical systems. By studying the molecular bases of cold adaptation in polar fish, and taking advantage of the information available on hemoglobin structure and function, we analysed the evolutionary history of the ${\alpha}\;and\;{\beta}globins$ of Antarctic and Arctic hemoglobin using the molecular clock hypothesis as a basis for reconstructing the phylogenetic relationships among species.

• 천문학논총
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• 제30권2호
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• pp.611-616
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• 2015

The Antarctic high plateau offers exceptional conditions for infrared and terahertz astronomy, as well as for programs requiring long, uninterrupted periods for measurements made with high cadence and photometric precision (i.e. time domain astronomy). In this review we summarise the special conditions of the Antarctic plateau which facilitate these observing regimes. We also outline some high profile science programs in each that could be conducted most effectively from the Antarctic high plateau, involving the first light in the Universe, the life cycle of our Galaxy, and the equation of state for the Universe. Three high plateau sites are under particular consideration for furthering such scientific programs{Dome A, Dome F and Ridge A. We summarise the activity underway at each site, which includes the building of new stations and the construction of facilities for optical, infrared and terahertz astronomy, as well as the plans for their future development.

• Ocean and Polar Research
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• 제26권2호
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• pp.155-163
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• 2004

The Protocol on Environmental Protection to the Antarctic Treaty was ratified in 1991. With the aim to ensure comprehensive protection of the Antarctic environment, it contains provisions on environmental protection and conservation of the Antarctic area, including provisions for Environmental Impact Assessment. Environmental Impact Assessment is a method used to predict environmental impacts at an early stage in project planning and design, and find ways to mitigate or prevent adverse impacts in order to maintain balance between development activities and environmental conservation. Internationally, the Environmental Impact Assessment (EIA) in the Antarctic is classified into three types - preliminary, Initial, and Comprehensive - based on the environmental impacts of the proposed activities. In case of the Preliminary Environmental Review (PER), proposed activity may proceed in accordance to the national procedures and drafting of an outline. However, Initial (IEE) and Comprehensive Environmental Evaluation (CEE) assess and verify the impacts of the proposed activity, and require methods or alternatives for mitigating or eliminating negative impacts on the environment. Although Korea's Act of 'Activities and Environmental Protection in Antarctica' also includes provisions on EIA for activities in Antarctica, there are obvious contrasts with the EIAs currently being conducted in Korea, in regards to deciding the level of EIA through screening and identifying key issues for assessment through scoping. In order to implement the proper EIA, more improved methods for drafting and reviewing the EIA to Antarctica in Korea are necessary.

• Fisheries and Aquatic Sciences
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• 제17권4호
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• pp.427-431
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• 2014

Mercury is an element of special concern for human health. Measurements of total mercury levels in fish have been taken into consideration to assess risk. In this study, the Antarctic toothfish Dissostichus mawsoni was evaluated as a potential safe food source through measurement of total mercury contents. Total mercury concentrations in Antarctic toothfish ranged from $0.101{\pm}0.047mg/kg$ to $0.139{\pm}0.075mg/kg$. The total mercury concentration was significantly correlated with macroscopic values including total fish length, weight, gonadosomatic index, and maturity (P < 0.01 or 0.05). Furthermore, according to the risk assessment, the total mercury body exposure rate from Antarctic toothfish ranged from 2.125% to 2.847% of the Provisional Tolerable Weekly Intake. Therefore, the Antarctic toothfish could be used as a potential safe seafood source.

• Ocean and Polar Research
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• 제45권3호
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• pp.155-172
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• 2023

The collapse of ice shelves is a process that can severely increase the rise of global sea-levels through the reduction of the buttressing effect of ice shelves and the consequent acceleration of the ice flow of ice sheets. In recent years, the West Antarctic ice shelves in the Amundsen Sea, whose buttressing effect is essential for a great part of the West Antarctic ice sheet, have been experiencing the most rapid melting and thinning in the world. The melting of the West Antarctic ice shelves is caused primarily by heat transported by Circumpolar Deep Water (CDW). For this reason, it is important to investigate ice-ocean interactions that could influence the melting of ice shelves and evaluate the stability of West Antarctic ice shelves. A lot of researchers have been actively investigating the West Antarctic ice shelves in the Amundsen Sea. High-impact journals have recognized the importance of and published studies on ice-ocean interactions occurring near and under the ice shelves as well as the connections among ice shelves. However, in situ observations are limited due to extreme weather and sea-ice conditions near the ice shelves; therefore, many scientific questions remain unanswered. This study introduces the characteristics of the Amundsen Sea and investigate the past and latest research issues in this region. This study also gives suggestions regarding important scientific questions and directions for future research that should help early-career scientists take the lead in future research on the melting dynamics of the West Antarctic ice shelves in the Amundsen Sea.

• Ocean and Polar Research
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• 제21권2호
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• pp.137-147
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• 1999

Penguins are one of the key constituent organisms in the Antarctic ecosystem. A total of 18 species of penguins occur only in the southern hemisphere from the Galapagos Archipelago to southern area off Australia and New Zealand, South Africa, South America, and the islands scattered in the Southern Ocean to the coast along the Antarctic Continent. In the Antarctic Treaty area, there are only 5 species of penguins such as Emperor (Aptenodytes forsteri), Gentoo (Pygoscelis papua ellsworthi), Adelie (P. adeliae), Chinstrap (p. antarctica), and Macaroni (Eudyptes chrysolophus) penguins. Two additional species, the King (Aptenodytes patagonicus patagonicus) and Rockhopper (Eudyptes chrysocome) penguins, however, are distributed within the Antarctic Convergence. In the vicinity of king Sejong Station located in King George Island, the South Shetland Islands off the Antarctic Peninsula, 5 species are observed, among which 2 Pygoscelis species such as the Gentoo and Chinstrap penguins hatch their eggs and raise their chicks at the rookery 2km south offing Sejong Station in summer. Adelie penguins hatch their chicks in other place in King George Island. One Emperor penguin roamed on the frozen Maxwell Bay which has been frozen every two or three years with the approximate thickness of 60cm. And one Macaroni penguin also visited the rookery in summer. We should carry out researches on the penguins occurring in the vicinity of King Sejong Station to monitor the environmental changes around King Sejong Station and the South Shetland Islands.

• Journal of Astronomy and Space Sciences
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• 제34권3호
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• pp.207-212
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• 2017

During the last glacial-interglacial transition, there were multiple intense climatic events such as the Bølling-Allerød warming and Younger Dryas cooling. These events show abrupt and rapid climatic changes. In this study, the climate events and cycles during this interval are examined through wavelet analysis of Arctic and Antarctic ice-core $^{18}O$ and tropical marine $^{14}C$ records. The results show that periods of ~1383-1402, ~1029-1043, ~726-736, ~441-497 and ~202-247 years are dominant in the Arctic region, whereas periods of ~1480, ~765, ~518, ~311, and ~207 years are prominent in the Antarctic TALDICE. In addition, cycles of ~1019, ~515, and ~209 years are distinct in the tropical region. Among these variations, the de Vries cycle of ~202-209 years, correlated with variations in solar activity, was detected globally. In particular, this cycle shows a strong signal in the Antarctic between about 13,000 and 10,500 yr before present (BP). In contrast, the Eddy cycle of ~1019-1043 years was prominent in Greenland and the tropical region, but was not detected in the Antarctic TALDICE records. Instead, these records showed that the Heinrich cycle of ~1480 year was very strong and significant throughout the last glacial-interglacial interval.