• ALGAE
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• 제19권1호
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• pp.39-47
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• 2004

Production dynamics of eelgrass, Zostera marina was examined in Jindong Bay on the south of the Korea peninsula. Eelgrass leaf productivities and environmental factors such as underwater photon flux density, water temperature, and nutrient availabilities in the water column and sediments were monitored from March 2002 to December 2003. While water temperature exhibited a distinct seasonal trend, underwater irradiance and nutrient availabilities exhibited high degree of fluctuation, and did not show a seasonal trend throughout the experimental periods. Eelgrass leaf elongation and production rates showed significant seasonal variations. Leaf productivity was highest in May (30.0 mg dry wt sht$^{-1}$ d$^{-1}$ or 3.7g dry wt m$^{-2}$d$^{-1}$) and lowest in November (3.2 mg dry wt sht$^{-1}$ d$^{-1}$ or 0.12 g dry wt m $^{-2}$ d$^{-1}$). Eelgrass leaf productivities did not show a strong correlation with underwater irradiance or environmental nutrient availabilities. The production rates, however, were positively correlated with water temperature during spring periods, and were correlated negatively at high water temperature exceeded 20℃ during summer months. While relative growth rates were highest in spring and lowest in high water temperature periods, plastochrone interval was longest during summer and shortest during spring. These results imply that seasonal growth dynamics of eelgrass, Z. marina was mainly controlled by water temperature.

• 센서학회지
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• 제5권2호
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• pp.55-60
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• 1996

The growth and microwave plasma assisted nitrogen doping of ZnSe by low pressure organometallic vapor phase epitaxy(OMVPE) has been investigated in a vertical downflow reactor equipped with a laser interferometer for in-situ growth rate measurements. Particular emphasis is placed on understanding growth characteristics of $H_{2}Se$ and the new adduct source dimethylzinc:triethyllamine($DMZn:NEt_{3}$) as compared with those obtained with $H_{2}Se$ and DMZn. At lower temperatures ($<300^{\circ}C$) and pressures(<30Torr), growth rates are higher with the adduct source and the surface morphology is improved relative to films synthesized with DMZn. Hall measurements and photoluminescence spectra of the grown films demonstrate that DMZn and $DMZn:NEt_{3}$ produce material with comparable electronic and optical properties. Microwave plasma decomposition of ammonia is investigated as a possible approach to increasing nitrogen incorporation in ZnSe and photoluminescence spectra are compared to those realized with conventional ammonia doping.

• 한국환경복원기술학회지
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• 제15권3호
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• pp.67-74
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• 2012

This study was carried out to cultivate evergreen-leaved tree container seedlings having low cost of equipment and easy to control. Two species of V. odoratissimum var. awabuki and Q. glauca planting in respective underground container were showed survival rate above 90%. The Relative growth rates of height was good in non-treatment and root collar diameter was no significant difference between treatments. The T/R ratio was respectively 1.1, 1.0 in container type of F, G. and root's biomass products was more effective than others. A container type of F showed better Quailty index than others with 16.2 values. Q. glauca was higher T/R ratio in root development than shoot and the quality index was high in container type of E, D with 4.0. 3.5, respectively. On the basis of the results obtained in this study, we can concluded that the underground container type was suitable to F in V. odoratissimum var. awabuki and to D or E in Q. glauca.

• Journal of Plant Biology
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• 제30권3호
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• pp.205-213
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• 1987

Soybean, inoculated with effective Rhizobium japonicum 110, were grown by sand culture with nutrient solution containing either of 0, 1, 3, 10 or 30mM NO3-/l, and analyzed growth characteristics, NR activity, N2-fixation activity, and changes of ureide contents during the growing period. The amount of nodule formation decreased abruptly by nitrate treatment, the maximum nodule dry weight was 1.59, 1.05, 0.78, 0.09 and 0.008 g plant-1, respectively for each treatment on the 98th day. Specfic activity of N2-fixation showed the maximum rates of 140, 101, 37, 5 and 2.2 nM dw.mg-1.hr-1, respectively for each treatment in the earlier growth period. The maximum acetylene reduction activity on the 98th day after sowing was 81.5, 35.3, 14.3, 0.1 and 0.0045 $\mu$M C2H4 plant-1.hr-1, respectively for 0, 1, 3, 10 and 30 mM of NO3- gradients. Nitrate reduction activity increased along with nitrate gradients, and decreased abruptly with age. Relative abundance of ureides in plant organs was high in reproductive growth, and showed the maximum value in fully symbiotic dependent plant. Relative abundance of ureides in stem is a useful indication for the evaluation of nitrogen fixation in nodules of symbiotic plant.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9731-9737
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• 2014

Large scale secular registry or surveillance systems have been accumulating vast data that allow mathematical modeling of cancer incidence and mortality rates. Most contemporary models in this regard use time series and APC (age-period-cohort) methods and focus primarily on predicting or analyzing cancer epidemiology with little attention being paid to implications for designing cancer registry, surveillance or evaluation initiatives. This research models age-specific cancer incidence rates using logistic growth equations and explores their performance under different scenarios of data completeness in the hope of deriving clues for reshaping relevant data collection. The study used China Cancer Registry Report 2012 as the data source. It employed 3-parameter logistic growth equations and modeled the age-specific incidence rates of all and the top 10 cancers presented in the registry report. The study performed 3 types of modeling, namely full age-span by fitting, multiple 5-year-segment fitting and single-segment fitting. Measurement of model performance adopted adjusted goodness of fit that combines sum of squred residuals and relative errors. Both model simulation and performance evalation utilized self-developed algorithms programed using C# languade and MS Visual Studio 2008. For models built upon full age-span data, predicted age-specific cancer incidence rates fitted very well with observed values for most (except cervical and breast) cancers with estimated goodness of fit (Rs) being over 0.96. When a given cancer is concerned, the R valuae of the logistic growth model derived using observed data from urban residents was greater than or at least equal to that of the same model built on data from rural people. For models based on multiple-5-year-segment data, the Rs remained fairly high (over 0.89) until 3-fourths of the data segments were excluded. For models using a fixed length single-segment of observed data, the older the age covered by the corresponding data segment, the higher the resulting Rs. Logistic growth models describe age-specific incidence rates perfectly for most cancers and may be used to inform data collection for purposes of monitoring and analyzing cancer epidemic. Helped by appropriate logistic growth equations, the work vomume of contemporary data collection, e.g., cancer registry and surveilance systems, may be reduced substantially.

• 수산해양교육연구
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• 제29권2호
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• pp.422-435
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• 2017

Intermolt periods, growth rates, survival (%) and relative growth of the megalopa larvae of Portunus trituberculatus (Miers, 1876) were studied up to the crab 7th stage for 160 days in the 3 different temperature groups in which each has 60 larvae. The higher the water temperature was the shorter the intermolt period was in each crab stage. In addition, a deviation of intermolt periods was shown as few as the water temperature gets higher. The intermolt period in the 7th crab stage was $29.8{\pm}3.26$ days in the experimental group at the room temperature, $45.2{\pm}3.89$ days at the temperature of $17^{\circ}C$, and $25.6{\pm}2.23$ days at the temperature of $27^{\circ}C$, respectively. The survival (%) of larvae of P. trituberculatus (the crab 7th stage) is the highest in the group at the room temperature: However, they showed 15% at the temperature of $27^{\circ}C$ and 10% at the temperature of $17^{\circ}C$. All the groups were shown the similar relative growth, but significant differences appeared in some comparison. The sizes (mean growth of carapace width) of the crabs in the group at the temperature of $27^{\circ}C$ reached 5.01~25.45 mm length (it is the longest among the groups) from the crab 1th to the crab 7th stage. However, the sizes (mean growth of carapace width) of room temperature were 4.99~22.26 mm and the size of crab in the group at the temperature of $17^{\circ}C$ reached 4.8~17.26 mm, The sizes (mean growth of carapace length) of the crabs in the group at temperature of $27^{\circ}C$ reached 2.88~13.56 mm, However, the size of the crab in the group at the room temperature showed 2.88~12.34 mm, while in the group at temperature of $17^{\circ}C$, their average growth of carapace length were 2.51~8.03 mm. The growth rates of larvae of P. trituberculatus (from the crab 1th to the crab 7th stage) were changed with the increase of the instar stage, however their changes showed irregular.

• 한국패류학회지
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• 제28권4호
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• pp.343-347
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• 2012

속성장을 위한 선발 1세대 전복 (Selected abalone : SA)의 성장률을 조사하기 위하여 동일 사육 환경 조건에서 대조구 전복 (Control abalone : CA) 과 비교실험을 하였다. 그 결과 각 성장형질 (각장, 각폭 및 중량) 은 SA구가 CA구보다 유의하게 빠른 것으로 나타났다. 45일째 및 90일째의 평균 각장에 있어 SA구가 CA구 보다 각각 31.7% 및 17.8% 빠르게 나타났으며, 중량에 있어서도 각각 43.7% 및 25.6% 빠른 것으로 나타났다. 더욱이 90일째의 각장과 중량의 상대성장 비교에 있어서도 SA구가 CA구 보다 유의적으로 높은 상관관계를 나타내었다. 이러한 결과는 선발육종기술을 이용하여 양식 전복의 성장률을 증대할 수 있는 가능성을 시사하고 있다.

• ALGAE
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• 제29권3호
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• pp.203-215
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• 2014

As global warming continues over the coming century, marine organisms will experience a warmer, more acidic ocean. Although these stressors may behave antagonistically or synergistically and will impact organisms both directly (i.e., physiologically) and indirectly (i.e., through altered species interactions), few studies have examined the complexities of these effects in combination. To address these uncertainties, we examined the independent and combined effects of elevated temperature and $pCO_2$ on the physiology of the adult sporophyte stage of giant kelp, Macrocystis pyrifera, and the grazing of the purple sea urchin Strongylocentrotus purpuratus. While elevating $pCO_2$ alone had no effect on M. pyrifera growth or photosynthetic carbon uptake, elevating temperature alone resulted in a significant reduction in both. However, when M. pyrifera was grown under elevated temperature and $pCO_2$ together, growth and photosynthetic carbon uptake significantly increased relative to ambient conditions, suggesting an interaction of these factors on photosynthetic physiology. S. purpuratus held under future conditions generally exhibited reduced growth, and smaller gonads than urchins held under present-day conditions. However, urchins fed kelp grown under future conditions showed higher growth rates, partially ameliorating this effect. Feeding rates were variable over the course of the experiment, with only the first feeding rate experiment showing significantly lower rates for urchins held under future conditions. Together, these data suggest that M. pyrifera may benefit physiologically from a warmer, more acidic (i.e., higher $pCO_2$) ocean while S. purpuratus will likely be impacted negatively. Given that kelp-urchin interactions can be important to kelp forest structure, changes to either of these populations may have serious consequences for many coastal environments.

• Ecology and Resilient Infrastructure
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• 제2권4호
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• pp.345-350
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• 2015

The toxicity of red mud (RM) pellets for water purification was evaluated using Pseudokirchneriella subcapitata and Daphnia magna in a lab-scale experiment. According to the algal growth inhibition test, both specific growth rates and relative growth rates of P. subcapitata decreased, and the growth inhibition rates increased ($R^2=0.97$, p<0.001) as the concentration of RM pellets in the aqueous solution increased (>1.6 g/L). Also, based on the acute toxicity evaluation test on D. magna, toxic unit (TU) values ranged between 0.00 and 2.83, and increased with an increase in the concentration of RM pellets in the aqueous solution. A correlation analysis indicated that the pH of RM pellets was statistically correlated with TU values ($R^2=0.77$, p=0.02). The environmental implication from this study is that the concentration of RM pellets in an aqueous solution needs to be lower than 4.4 g/L to keep the maximum permissible TU value less than 1.0.

• Fisheries and Aquatic Sciences
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• 제15권1호
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• pp.37-41
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• 2012

Autotransgenic manipulation with a growth hormone (GH)-construct is a potential approach to improving the growth rates of farmed fish. Here, we present the generation of GH-autotransgenic common carp Cyprinus carpio carrying a transgene comprised of the carp homologous GH gene and a ${\beta}$-actin regulator. Autotransgenic carp showed similar viability to their non-transgenic siblings. Early growth characteristics of founder autotransgenic carp up to 50 days postfertilization were highly variable among individuals; i.e., some fish exhibited significant growth depression, while others showed dramatic acceleration of growth, achieving greater than sixfold increases in body weight relative to their non-transgenic counterparts. Stimulated growth performance became more notable with age and many transgenic individuals of the largest class reached 5 kg within 8 or 9 months, which is at least 10 times heavier than the average body weight of communally grown non-transgenics. Four of six founder transgenic males were successful in passing the transgene to their $F_1$ offspring with frequencies ranging from 19 to 36%. Growth stimulations were also persistent in all $F_1$ progeny groups examined.