• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.81-81
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• 2003

DNA methylation is a covalent modification of DNA that can modulate gene expression and is now recognized as a major component of the epigenome. During evolution, the dinucleotide CpG has been progressively eliminated from the genome of higher eukaryotes and is present at only 5% to 10% of its predicted frequency. Approxymately 80% of the remaining CpG sites contain methylated cytosines in most vertebrates and they are distributed in a pattern that is unique in each tissue and is inversely correlated with gene expression. The pattern of methylation is faithfully maintained during cell division by the enzyme Dnmt1, the maintenance DNA methyltransferase, which catalyzes the transfer of a methyl group from S-adenosyl-methionine to the 5'-position of the cytosine ring. We have been identified bovine Dnmt1 cDNA full-length recently (AY173048) Little is known on the functions of Dnmt1 in bovine preimplantation embryos. Thus, we analyzed the specific pattern of Dnmt1 in in vitro derived/nuclear transfer bovine and in vivo derived mouse embryos to monitor the epigenetic reprogramming process. We investigated these process by using indirect immunofluresence with an antibody to Dnmt1. According to other studies, Dnmt1 accumulates in nuclei of early growing oocytes but is sequestered in the cytoplasm of mature oocytes. In 2-cell and 4-cell embryos, Dnmt1 is cytoplasmic, but at the 8-cell stage, it is present only in the nucleus. By the blastocyst stage, Dnmt1o is again found only in the cytoplasm. Thus, nuclear localization of Dnmt1o in preimplantation embryos is limited to the 8-cell stages After implantation, Dnmt1 is localized in the nucleus in mouse. However, we have found different patterns of Dnmt1 nuclear localization. Though we used the common antibody, immune-localization data revealed that Dnmt1 antibody have been detected at the nucleus in 1-cell to blastocyst embryos. Therefore, maybe we think that the functions of Dnmt1 between bovine and mice are different. In order to Identify the mechanisms that regulate DNA methylation in bovine preimplantation embryo, we have plans on using bovine oocyte and somatic specific Dnmt1 antibodies.

• Korean Journal of Radiology
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• 제2권3호
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• pp.138-144
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• 2001

Objective: Bronchogenic carcinoma can mimic or be masked by pulmonary tuberculosis (TB), and the aim of this study was to describe the radiologic findings and clinical significance of bronchogenic carcinoma and pulmonary TB which coexist in the same lobe. Materials and Methods: The findings of 51 patients (48 males and three females, aged 48-79 years) in whom pulmonary TB and bronchogenic carcinoma coexisted in the same lobe were analyzed. The morphologic characteristics of a tumor, such as its diameter and margin, the presence of calcification or cavitation, and mediastinal lymphadenopathy, as seen at CT, were retrospectively assessed, and the clinical stage of the lung cancer was also determined. Using the serial chest radiographs available for 21 patients, the possible causes of delay in the diagnosis of lung cancer were analyzed. Results: Lung cancers with coexisting pulmonary TB were located predominantly in the upper lobes (82.4%). The mean diameter of the mass was 5.3 cm, and most tumors (n=42, 82.4%) had a lobulated border. Calcification within the tumor was seen in 20 patients (39.2%), and cavitation in five (9.8%). Forty-two (82.4%) had mediastinal lymphadenopathy, and more than half the tumors (60.8%) were at an advanced stage [IIIB (n=11) or IV (n=20)]. The average delay in diagnosing lung cancer was 11.7 (range, 1-24) months, and the causes of this were failure to observe new nodules masked by coexisting stable TB lesions (n=8), misinterpretation of new lesions as aggravation of TB (n=5), misinterpretation of lung cancer as tuberculoma at initial radiography (n=4), masking of the nodule by an active TB lesion (n=3), and subtleness of the lesion (n=1). Conclusion: Most cancers concurrent with TB are large, lobulated masses with mediastinal lymphadenopathy, indicating that the morphologic characteristics of lung cancer with coexisting pulmonary TB are similar to those of lung cancer without TB. The diagnosis of lung cancer is delayed mainly because of masking by a tuberculous lesion, and this suggests that in patients in whom a predominant or growing nodule is present and who show little improvement of symptoms despite antituberculous or other medical therapy, coexisting cancer should be suspected.

• 한국식생활문화학회지
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• 제5권2호
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• pp.235-241
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• 1990

두릅나무 Aralia elata순의 saponin을 분리하여 조사한 결과는 다음과 같다. 1. Saponin의 함량과 종류는 자연산이 온상산보다 많고, 가열에 의해서는 모두 감소하였으며, 잎이 자랄수록 그 함량은 증가하였다. 자연산 날것 식용적기(Nr2)의 총 saponin 종류는 37개였다. 2. 자연산의 saponin 패턴은 생육시기에 따라 변하였으며 날것 식용적기(Nr2)가 다른 것에 비해서 크게 달랐다. 그러나 가열 처리한 결과는 saponin 패턴이 변화되어 시기적 차가 줄었다. 온상산은 자연산에 비해 피크가 단순하고 시기별 차이는 적었지만 가열에 의한 패턴의 차도 적었다. 3. 자연산 날것 식용적기는 ‘b’ saponin이 특이하게 많았고 나머지에서는 ‘d’ saponin이 가장 많았다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권6호
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• pp.338-348
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• 2003

In the past decade, considerable progress has been made in developing the appropriate biotechnology for microalgal mass cultivation aimed at establishing a new agro-industry. This review points out the main biological constraints affecting algal biotechnology outdoors and the requirements for making this biotechnology economically viable. One of them is the availability of a wide variety of algal species and improved strains that favorably respond to varying environmental conditions existing outdoors. It is thus just a matter of time and effort before a new methodology like genetic engineering can and will be applied in this field as well. The study of stress physiology and adaptation of microalgae has also an important application in further development of the biotechnology for mass culturing of microalgae. In outdoor cultures, cells are exposed to severe changes in light and temperature much faster than the time scale re-quired for the cells to acclimate. A better understanding of those parameters and the ability to rapidly monitor those conditions will provide the growers with a better knowledge on how to optimize growth and productivity. Induction of accumulation of high value products is associated with stress conditions. Understanding the physiological response may help in providing a better production system for the desired product and, at a later stage, give an insight of the potential for genetic modification of desired strains. The potential use of microalgae as part of a biological system for bioremediation/detoxification and wastewater treatment is also associated with growing the cells under stress conditions. Important developments in monitoring and feedback control of the culture behavior through application of on-line chlorophyll fluorescence technique are in progress. Understanding the process associated with those unique environmental conditions may help in choosing the right culture conditions as well as selecting strains in order to improve the efficiency of the biological process.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.36-36
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• 2003

In the present study, growth performances of the offspring from selected brood line were compared to those of the offspring from non-selected brood line of red sea bream. Offspring groups were mass produced separately from two brood lines, selected and non-selected Korean strain. Selected brood line have been selected by fish size for four generations (upper 5∼30% per generation) and non-selected brood line is the second generation of wild population at south sea in Korea. There's no significant difference in body length between offspring from selected and non-selected brood line during early growing stage (until 96-days old). However, offspring from selected brood line had superior body weight growth than offspring from non-selected brood line. At sea cages rearing trials with communal stocking, Offspring from selected brood line showed significantly better performance in body weight, body length, weight gain, specific growth rate and feed consumption (but not in feed conversion ratio) than offspring from non-selected brood line. At 24 months old, offspring from selected brood line grew faster 1.10 times in body length and 1.41 times in body weight than offspring from non selected brood line. The response to selection when compared to a non-selected line is on average of 10% in weight per generation at 24 months old.

• 정보관리학회지
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• 제21권1호
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• pp.187-207
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• 2004

최근에 이르러 차세대 웹 아키텍처인 시멘틱 웹에 관한 연구에 대한 관심이 증대되고 있다. 정보학적인 관점에서, 차세대 웹 아키텍처인 시멘틱 웹은 하나의 거대한 메타데이터 조직으로 볼 수 있다 시멘틱 웹을 거대한 메타데이터 조직으로 볼 수 있는 가장 큰 이유는, 시멘틱 웹을 구축 과정에서 가장 중요한 단계 중 하나가 웹 정보자원에 대한 정형화된 메타데이터를 작성하는 것이기 때문이며, 이용자는 메타데이터를 이용하여 보다 쉽게 자신이 원하는 정보를 찾을 수 있다. 본 논문에서는, 시멘틱 웹 환경 하에서 서로 다른 정보체계구조를 지닌 개방형 전자도서관간의 상호 운영성을 제공하기 위하여 새로운 방식의 응용프로화일 메타데이터구조를 개발하였다. 새로운 방식의 응용프로화일 메타데이터구조를 토대로, 개방형도서관모델에서 서로 다른 형태의 대규모메타데이터를 통합하기 위한 통합메타데이터 자동생성 및 통합검색 알고리즘을 개발하였다.

• Journal of Forest and Environmental Science
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• 제28권1호
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• pp.12-18
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• 2012

Like any other natural resources, forest flora may experience the extreme threat of elevated temperature and saline water submergence at different stages of their lives i.e. from germination to maturity due to climate change effects. The overall aim of the study was to measure the effect of higher temperatures along with saline water irrigation on survival and initial growth during seedling stage of Artocarpus chapalasha. The experiment was conducted in temperature- humidity-photoperiod regulated plant growth chamber during stipulated period to measure the growth performance of randomly selected seedlings. Within three different elevated temperatures viz. $30^{\circ}C$, $32^{\circ}C$ and $34^{\circ}C$, the seedlings were given three different saline conditions such as 0.5 g/L, 1.5 g/L and 2.5 g/L NaCl concentrations. Results found from the experiment was that, seedlings of Artocarpus chaplasha reared at different temperatures and saline water treatments showed stunted growth than reared at existing outdoor temperature ($26.31^{\circ}C$) irrigated with regular fresh water. Seedling growth at three different parameters such as height, collar diameter and number of leaves showed that with increasing temperature individuals respond negatively to increasing saline condition. The seedling's growth occurred at every day in height, collar diameter and leaf. However, growth rate reduced later during the observation. The combined effect of high salinity and higher elevated temperature results in seedling mortality. Therefore, Artocarpus chaplasha may not thrive at higher temperature and salinity intrusion at its early growing period in plantation and natural forest areas.

• 한국토양비료학회지
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• 제45권2호
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• pp.312-316
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• 2012

1. 우리나라 북부 8개 지역을 대상으로 하여 최근 30년간의 기상자료 분석에 의한 12월~6월의 일평균 PET는 $2.31mm\;day^{-1}$ 이었다. 2. 시설재배 고추의 우리나라 북부 8개 지역별, 3개 토성 및 16개 순별, 총 384경우의 재배여건에 적합한 물 절약형 적정 관개간격 및 1회 관개량을 산정하였다.

• Journal of Ecology and Environment
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• 제38권4호
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• pp.493-503
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• 2015

This study analyzed how spatial distribution of Himantormia lugubris is affected by the microenvironment in the Antarctic Specially Protected Area (ASPA) No. 171 located in the Barton Peninsula of King George Island that belongs to the maritime Antarctic. In order to determine the population structure of H. lugubris growing in Baekje Hill within ASPA No. 171, we counted the individuals of different size groups after dividing the population into 5 growth stages according to mean diameter as follows: ≤ 1 cm, 1-3 cm, 3-5 cm, 5-10 cm, and ≥ 10 cm. The count of H. lugubris individuals in each growth stage was converted into its percentage with respect to the entire population, which yielded the finding that stages 1 through 5 accounted for 32.8%, 25.3%, 15.9%, 22.5%, and 3.5%, respectively. This suggests that the population of H. lugubris in ASPA No. 171 has a stable reverse J-shaped population structure, with the younger individuals outnumbering mature ones. The mean density of H. lugubris was 17.6/0.25 m², mean canopy cover 13.3%, and the mean dry weight 37.8 g/0.25 m². It began to produce spore in the sizes over 3 cm, and most individuals measuring 5-10 cm were adults with sexually mature apothecia. The spatial distribution of H. lugubris was highly heterogeneous. The major factors influencing its distribution and performance were found to be the period covered by snow, wind direction, moisture, size of the substrate, and canopy cover of Usnea spp. Based on these factors, we constructed a prediction model for estimating the spatial distribution of H. lugubris. Conclusively, the major factors for the spatial distribution of H. lugubris were snow, wind, substrate and the competition with Usnea spp. These results are important for understanding of the distribution in the maritime Antarctic and evolution of H. lugubris that claims a unique life history and ecological niche.

• 대한기계학회논문집B
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• 제38권6호
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• pp.493-500
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• 2014

Damk$\ddot{o}$hler수가 클 때 복사열손실에 의한 소염근처에서 셀모양의 대향류확산화염의 특성에 대하여 수치해석적으로 연구하였다. Lewis 수를 0.5로 두고 일차원 정상상태의 화염의 해에 매우 작은 교란을 가하여 시간에 따른 화염전개를 계산하였다. 천이과정 초기에는 선형안정성 해석에서 예측된 결과와 매우 비슷하게 진행된다. 시간이 증가함에 따라 증가율이 가장 강한 파동수를 갖는 교란파가 성장하고, 완전히 발달되면 소염영역과 화염영역이 번갈아 나타나는 셀모양의 화염구조를 갖는다. 화염온도는 총엔탈피의 국소 이득 때문에 일차원 정상상태의 화염온도보다 높다. 셀모양의 확산화염은 Damk$\ddot{o}$hler 수가 증가함에 따라 셀의 모양이 원형으로 되며 일차원 정상상태 소염조건보다 큰 Damk$\ddot{o}$hler 수에서도 셀모양의 화염은 꺼지지 않고 살아남는다.