• 한국수산과학회지
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• 제41권1호
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• pp.1-6
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• 2008

The changes in osmolality and the gene expression profiles of prolactin (PRL) and growth hormone (GH) with rapid changes in salinity were compared in the eel (Anguilla japonica), crucian carp (Carassius carassius), and masu salmon (Oncorhynchus masou). Fish stocked in freshwater (FW) were abruptly transferred to experimental tanks containing FW, 50% seawater (50% SW), or 100% SW (SW). Blood samples and pituitary glands were collected 2 and 24 hrs after the exposure. No mortality was observed in SW eel (n=6), whereas all of the crucian carp (n=6) and two masu salmon (n=6) exposed to SW died after land 24 hrs, respectively. The PRL mRNA levels of the eel and masu salmon decreased in 50% SW and SW compared to those of the fish kept in FW after 24 hrs, whereas the PRL levels of crucian carp were higher in 50% SW than in FW. Unlike the PRL mRNA levels, the GH mRNA levels of the eel did not differ significantly among three different salinities, while the GH mRNA levels of crucian carp and masu salmon increased significantly in 50% SW and SW after 24 hrs. The serum osmolalities increased marginally in the eel and masu salmon in 50% SW at 24 hrs (19% and 9%, respectively), whereas those of crucian carp increased abruptly in 50% SW (50% increase). These results suggest that the synthesis of PRL and GH is important in relation to the osmoregulatory system with environmental changes in salinity.

• 문화기술의 융합
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• 제9권2호
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• pp.113-118
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• 2023

본 연구는 주택구입능력을 포함한 거시경제변수와 은행 대출 관련 변수들이 주택가격 변동에 미치는 영향을 다중회귀모형을 이용하여 분석하였다. 분석 결과, 소비자물가 상승률, 총통화 증가율 및 주택구입부담지수 증가율은 전국 주택가격의 변동에 유의한 양의 영향을 미치는 것으로 나타났다. 주택가격의 상승기와 하락기로 구분하여 분석한 결과, 주택가격 상승 기간 동안 소비자물가상승률과 총통화 증가율은 전국, 서울 및 경기의 주택가격에 유의하게 양의 영향을 미치는 것으로 나타난 반면에, 주택가격 하락 기간 동안 GDP 성장률은 주택가격 상승기와는 달리 주택가격에 유의하게 음의 영향을 미친 것으로 나타났다. 가계대출증가율도 주택가격 상승기와는 달리 주택가격에 유의한 양의 영향을 미치는 것으로 나타나났다. 반면에 주택담보대출증가율은 주택가격 상승기와는 달리 전국, 서울 및 경기의 주택가격에 유의한 음의 영향을 미치는 것으로 나타났다. 주택구입부담지수 증가율은 주택가격 상승기에는 주택가격에 대해 유의하게 양의 영향을 미치지 않으나, 주택가격 하락기에는 유의한 양의 영향을 보이는 것으로 나타났다. 주택가격결정 변수들은 주택가격 상승기와 주택가격 하락기에 서로 다른 양상을 보이는 것으로 나타났다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.736-737
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• 2015

In these days, international construction market including construction companies has much grown due to globalization and economic boom in the mid 2000's. The size of international construction market, measured with overseas revenue of 225 construction firms, has expanded 2.7 times from 2003 to 2008 according to the ENR. However, after the global financial crisis of 2008 it has faced condition of low growth. In this research, major changes of international construction market and top contractors have been studied. In this study, changes of international construction market have been analyzed in the aspect of region and product including general buildings, transportation, petroleum, etc. Then, in order to find the changes of top contractors which obtained good accomplishment, business performance of companies have been examined by the compound annual growth rate, profit margin and international revenue by comparing the data before 2008 and after. The purpose of the study is to understand major changes of international construction market. Also, strategy changes of top contractors against market stagnation, profit depreciation, high competition have been inferred through the study. The result of the study would contribute to analyzing the strategies of construction companies in international market.

• KSBB Journal
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• 제27권5호
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• pp.301-307
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• 2012

The hyphal growth, production of color pigments and monacolin K by Monascus strains were investigated in liquid medium. Thirty five different strains were collected and cultured in potato dextrose yeast extract broth (PDYB), potato dextrose broth (PDB) and malt extract broth (MEB) medea at $25^{\circ}C$ for 7 days. The growth rates of most of strains were highest in PDYB medium. Growth rate as well as pigment production were influenced by suspension conditions of mycelia during liquid cultivation. Most of strains producing monacolin K corresponded to strains producing red pigment highly and showing more pH changes of liquid media. Monacolin K produced from strains was detected in culture broth as well as mycelia. Any citrinin was not detected in monacolin K producing strains. These results imply that the selection of the strains producing red pigment highly and showing more pH changes in liquid cultivation could be applied for primary screening of Monascus strains for preparation of red mold rice.

• 한국환경과학회지
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• 제5권6호
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• pp.813-826
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• 1996

발아후 7일된 팥유식물에서 alumlnlum(Al)이 생장, 엽록소 함량, ALAD활성 및 뿌리와 경엽부의 형태에 미치는 영향을 조사하였다. 저농도(50, 100 $\muM)의$ Al처리에 의해 뿌리와 경엽부의 신장이 매우 감소되었으며 농도가 증가함에 따라 생장이 더욱 억제되었다. 따라서 생장억제는 농도의존적이었다. 뿌리신장은 Al 처리 24시간에서 감소되었으며 7일간의 저농도처리에 의해 억제효과가 회복되는 경향을 보여주었다. Al의 독성증상과 생장반응은 경엽부에 비해 뿌리에서 더 크게 나타났다. Hematoxylin 염색법에 의해 Al 분포를 조사한 결과 Al은 근단을 통해 표피와 피층세포에 축적되어 있음을 알 수 있었다. 한편 Al처리는 엽록소함량을 감소시켰으며, ALAD활성 또한 억제시켰다. 엽록소 함량과 ALAD 활성 간에는 양의 상관관계가 나타났다. Al 처리에 의한 뿌리의 형태변화를 보면 표피세포 및 피층세포의 변형 또는 파괴가 관찰되었으며, 뿌리직경과 피층의 체적도 매우 감소되었다. 경엽부에서도 Al처리는 직경과 세포크기의 감소를 보여주었다. 그러나 잎에서의 형태적 변화는 엽록체수와 크기변화 이외에는 거의 관찰되지 않았다. 이와 같은 결과에서 Al의 독성효과는 1차적으로 뿌리에서 나타나며, 뿌리형태의 변화는 뿌리의 생장패턴과 관련이 있음을 알 수 있었다. 따라서 Al은 팥유식물에서 특히 뿌리의 형태와 기능적 손상을 일으키는데 큰 영향을 미치는 것으로 생각된다.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.78-84
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• 1999

Ultrastructural changes in the cuticle of Paleamon serrifer associated with the intermolt cycle were examined and quantified as changes in the cuticular thickness. The cuticular thickness in each zoea stage increased with time elapsed after molting. The cuticle in the premolt stage was about 1.5 and 3 times thicker than that in the postmolt and intermolt stage, respectively. The cuticle in the premolt stage, including the molting space, was more than 5 times as thick as in the postmolt stage. In addition, newly hatched larvae were individually reared in the laboratory and body length for each specimen was measured frequently until the end of zoea VI. An average increase in body length between one zoea stage and the next is about $10\%$ of the length of the previous stage. Within individual zoea stages, the premolt stage had a body length some 0.3% longer than that of the postmolt stage, indicating a growth rate of about 0.03 mm/d.

• 한국분말재료학회지
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• 제29권2호
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• pp.110-117
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• 2022

The grain growth behavior in the (1-x)K_0.5Na_0.5NbO₃-xCaZrO₃ (KNNCZ-x) system is studied as a function of the amount of CZ and grain shape. The (1-x)K_0.5Na_0.5NbO₃-xCaZrO₃ (KNNCZ-x) powders are synthesized using a conventional solid-state reaction method. A single orthorhombic phase is observed at x = 0 - 0.03. However, rhombohedral and orthorhombic phases are observed at x = 0.05. The grain growth behavior changes from abnormal grain growth to the suppression of grain growth as the amount of CaZrO₃ (CZ) increases. With increasing CZ content, grains become more faceted, and the step-free energy increases. Therefore, the critical growth driving force increases. The grain size distribution broadens with increasing sintering time in KNNCZ-0.05. As a result, some large grains with a driving force larger than the critical driving force for growth exhibit abnormal grain growth behavior during sintering. Therefore, CZ changes the grain growth behavior and microstructure of KNN. Grain growth at the faceted interface of the KNNCZ system occurs via two-dimensional nucleation and growth.

• 한국의류학회지
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• 제6권1호
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• pp.51-59
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• 1982

Growth is marked by changes in body shape as well as in body size. Increase in size is described quantitatively by increments over time : changes in shape are complex and perhaps are not possible to quantify satisfactorily. Simply to define or describe static body shape quantitatively is difficult, and traditionally simple ratios or indices have been used. In order to find out the body proportion and the body type of the Korean males and females from 6 to 24 years, the material of measurements obtained by the Korean Body-build Investigations (measured in 1979) was calculated and analyzed. The results are as follows: 1. The growth of the trunk part of the body precedes that of the lower part. Comparing the growth rate of male and female, the latter is higher than the former, especially in 12. 2. When a comparison is made between 6, 9, 12, 15 years and grown-ups(20$\~$24 years) with their respective stature's taken as 100, then values of these children are larger in the measurements related with head, acromial and waist height but smaller in lower extremities than these of the grown-ups. 3. Body proportion changes gradually from infant to adult body type indicating different phases each sex.

• Journal of Plant Biology
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• 제14권3호
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• pp.21-28
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• 1971

Dry matter production, leaf area growth and total nitrogen changes were studied in Glycine max. soybean communities, which were grown in sandy loam soils controlled to provide various moisture levels, i.e., 5-7%(level 1), 8-10%(level 2), 11-13%(level 3), 14-15%(lev디 4), 17-20%(level 5) and 22-24%(level 6). A summary of the results is shown. The maximum dry matter production of leaves, stems and nodules and the maximum leaf area per unit area were at level 5, but the maximum of root dry matter production was at level 4. Total nitrogen content of the soybean plant decreased with growth, but each level of soil moisture content also showed a little difference. Water content of the plant decreased with plant age and soil water deficiency, especially in roots and nodules. Nodule formation increased in proportion to soil moisture content. total nitrogen content of the soil on which the soybeans grew, increased from 0.23% before sowing to 0.30% at 100 days after sowing. It seems that soil water content acts as a linear factor in the elongation or dry weight increase of shoots and roots until increasing to level 5. Considering the pattern of plant growth through analysis of the shoot and root dry weight ratio, or the photosynthetic organ and non-photosynthetic organ dry weight ratio, the asymptote of plant growth at a high soil water content exceeded that at a low soil water content.

• 한국환경과학회지
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• 제21권3호
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• pp.267-276
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• 2012

Spaceflights results in the reduction of immune status of human beings and increase in the virulence of microorganisms, especially gram negative bacteria. The growth of Klebsiella pneumoniae is enhanced by catecholamines and during spaceflight, elevation in the levels of cortisols occurs. So it is necessary to know the changes in physiology, virulence, antibiotic resistance and gene expression of K. pneumoniae under microgravity conditions. The present study was undertaken to study effect of simulated microgravity on growth, morphology, antibiotic resistance and cross stress resistance of K. pneumoniae to various stresses. The susceptibility of simulated microgravity grown K. pneumoniae to ampicillin, penicillin, streptomycin, kanamycin, hygromycin and rifampicin were evaluated. The growth of bacteria was found to be fast compared with normal gravity grown bacteria and no significant changes in the antibiotic resistance were found. The bacteria cultured under microgravity conferred cross stress resistance to acid, temperature and osmotic stress higher than the normal gravity cultured bacteria but the vice versa was found in case of oxidative stress.