• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.413-420
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• 2020

We analyzed the growth characteristics of each cell line and acclimating substrate of Larix kaempferi plantlets regenerated from somatic embryos, with the goal of increasing the survival rate during the acclimation phase. Somatic embryos from three embryogenic cell lines (L14-66, L16-18, and L17-B4) were used, and the acclimating substrates were commercial soils for Larix species (Larix-Soil) and horticultural corps (Hort-Soil), Elle-pot, and Peat-plug. The average initial shoot and root length was shortest in L14-66 and longest in L17-B4. The average survival rate by cell line was highest (87.0%) in L17-B4 and lowest (64.3%) for L14-66. Survival rates by substrate were highest in Elle-pot (88.5%) and Peat-plug (88.9%). The initial shoot length of the L14-66 plantlets was highly correlated with survival rates in the Larix-Soil (r = 0.852), Hort-Soil (r = 0.692), and Elle-pot (r = 0.867) substrates, but not in Peat-plug with high total nitrogen content. The initial shoot length of the L17-B4 plantlets was not correlated with the survival rate in any of the substrates. The initial root length of the L14-66 plantlets was highly related to survival rates in the Larix-Soil (r = 0.986), Elle-pot (r = 0.846), and Peat-plug (r = 0.802) substrates, and the survival rate of the plantlets was higher as the initial root length was longer. The initial root length of the L17-B4 plantlets was related to survival rate only in the Larix-Soil (r = 0.896) and Elle-pot (r = 0.696) substrates. In conclusion, to increase the survival rate of plantlets, root length should be considered over shoot length, and it is recommended to use substrates with high nitrogen content, such as Peat-plug, or to add fertilizer, during the acclimating process. In addition, in order to increase the survival rate, lines with high initial growth should be developed.

• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.334-337
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• 2005

Pine wood nematode isolates from Haman, Gyoungsangnam-do were cryopreserved with three different cryoprotectants (glycerol, ethylene glycol and dimethylsulfoxide), Nematode Growth medium (NGM) and M 9 buffer solution, respectively, and then survival rate, reproduction ability, and pathogenicity of stored nematodes were compared. Survival rates of juvenile was excellent in 15% glycerol solution as $72{\pm}5.3%$. The survival ability of nematodes at juvenile stage was more efficient than that of nematodes at adult stage. Pre-incubation treatment at $4^{\circ}C$ before storing in liquid nitrogen didn't affect the survival ability of pine wood nematode. When the reproduction ability of nematodes was confirmed on Botrytis cinerea agar plates at $28^{\circ}C$ incubator, there was no difference between cryopreserved and non-cryopreserved. Pathogenic ability of cryopreserved nematodes was also evaluated and confirmed by artificially inoculating them on 2-year old red pine seedlings.

• Journal of Aquaculture
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• v.13 no.1
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• pp.69-78
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• 2000

Bioactivity growth and survival rte of yolk sac larvae in cultured black seabream (Acanthopogrus schlegeli) red seabream (Pagrus major) and olive flounder (Paralichthys olivaceus) to 5 different concentration (0, 25, 50, 75 and 100%) of water soluble fraction (WSF) of Kuwait crude oil were studied. The 75% and 100% of WSF concentration influenced negatively on the length growth of larvae in each species so the growth rates of total length in the concentration of WSF were significantly lower than those of control. The high concentration (50%, 75%, and 100%) of WSF influenced negatively not only on the swimming frequency and speed but also on the morphological abnormality of larvae. Red seabream larvae showed the highest rate of abnormality by WSF among the tested fishes. The fish larvae exposed during pre-and post-hatch (egg and larval stages) and during post-hatch (larval stage only) to the WSF were significantly influenced on their survival rate. The larvae of red seabream were more sensitive to WSF than those of black seabream and olive flounder. The survival rates of larvae exposed to higher concentration (50%, 75%, and 100%) of WSF were significantly lower than those of the control but those of the 25% group were not.

• Journal of Technology Innovation
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• v.26 no.4
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• pp.98-121
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• 2018

This article analyzes the survival of Korean software firms from 1995 to 2015 by Cox regression model and product-limit method. The results show that survival rates are different for each sector: IT service, package software, game software and internet service. In addition, firm growth and investment in research and development positively affect software firm's survival, while slack resources negatively affect the software firm's survival. The implication of this study is that characteristics of the software industry and technologies should be taken into consideration in survival strategy of software firms and government policy. Previous research on survival analysis has been mainly conducted in the manufacturing industry or at the special circumstance such as the foreign exchange crisis of Korea in the late 1990s. The contribution of this study is that expanding the survival analysis to software firms in Korea which are becoming more important recently.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.874-881
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• 1997

In order to estimate toxicity of copper, radmium and chromium on survival, growth and oxygen consumption of the estuarine mysid, Neomysis awatschensis, adult and juvenile, the experiments were conducted by renewal bioassay method at $20{\pm}1^{\circ}C\;and\;20{\pm}1\%_{\circ}$ salinity. The $96hr-LC_{50}$ of the mysid exposed to cadmium, copper and chromium was 20.2, 11.3 and $670.4\;{\mu}g/\ell$ in adut and 3.4, 1.9 and $49.4\;{\mu}g/\ell$ in juvenile, respectively, and were ranked in order of toxicity : copper >cadmium >chromium. Survival rates of the mysid exposed to the sublethal concentrations of heavy metals for 40 days were significantly affected by cadmium $\geq1.0\;{\mu}g/\ell$ and copper $\geq0.6\;{\mu}g/\ell$ concentrations. The growth rate of the mysid exposed to $cadmium\geq2.0\;{\mu}g\ell$ and copper $\geq1.2\;{\mu}g/\ell$ concentrations were significantly reduced than that exposed to normal condition, but there was no affect on intermoult period. Oxygen consumption rate of the mysid exposed to heavy metals was significantly reduced with increasing heavy metals concentrations. The results of the present study led us to conclude that concentrations levels cadmium$\geq1.0\;{\mu}g\ell$ and copper $\geq0.6\;{\mu}g\ell$ of the estuarine could markedly affect the distribution and population of the mysid by reduced survival, growth and oxygen consumption rate.

• Journal of Aquaculture
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• v.11 no.2
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• pp.183-191
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• 1998

To substitute fromzed and freeze-dried food for live food in the development of the artificial seedling production of bivalve larvae, the dietary value of live T. suecica was compared with those of freeze-dried T. suecica, frozed T. suecica, live T. suecica (50%)+frozen T. suecica (50%), and live T. suecica (50%)+freeze-dried T. suecica (50%) in the rearing of oyster (Crassotrea gigas) and hen clam (Mactra chinensis) larvae, and manila clam (Tapes philipninarum) spats. Oyster larvae fed live T. suecica showed the highest growth (shell hight $231.9^{\mu}$m) and survival rate (72.6%) and those fed freeze-dried T. suecica showed the lowest growth (shell height $168.9^{\mu}$m) and survival rate (35.3%). However, in the hen clam larvae, there were not significantly different among diet group in growth and survival rate. The small spats of manila clam fed live t. suecica or live T. suecica (50%)+freeze-dried T. suecica (50%) showed higher growth and survival rate than those fed other diet group. In the case of large spats of manila clam, live T. suecica and live T. suecica (50%)+frozen T. suecica (50%) showed better growht. But, survival rates were not different among diet groups. Dietary valuse of frozen and dried T. suecica were different on species and growth stage, and frozen and freeze-dried T. suecica can be partially used as substitute food for T. suecica live T. succica in shellfish hatchery.

• The Korean Journal of Ecology
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• v.8 no.4
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• pp.179-196
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• 1985

By using temperatures as a key variable, a simulation model was constructed to predict the size and developmental speed for the German cockroach population. The following three research steps were conducted to implement the individual simulation technique to represent the basic life system of the cockroach. First, informations on developmental periods and survival rates in each life stage were obtained through rearing experiments at five different temperatures. Secondly, biological parameters needed for modeling were obtained based on these rearing results. The logistic equation was applied to calculating the developmental speed, while the averages of survival rates were utilized as parameters determining population size. And thirdly, a basic life model was constratued in a stimulative framework in FORTRAN for predicting the populating development on the individual basis. For this purpose the biological characteristics, such as life stage, age in days, developmental speed, fecundity, etc., were assigned as an inherent attribute of the transactiion so that they could accompany each individual automatically all through the simulation. This gave the model flexibility and applicability in representing the isnect life system. The save memory space in computer programing, two files were utilized in translocating the individual informations each other as time proceeded. The developed model could be effectively used as a strategic tool in interpreting and managing the cockroach population. It was also suggested in this study that the individual simulation could efficiently serve as a basis to formulate a fundamental framework on which the advanced and complex life process could be built.

• Journal of Digestive Cancer Research
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• v.3 no.1
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• pp.11-16
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• 2015

The discovery of HER2, a biomarker in advanced gastric cancer, and successful clinical trial using trastuzumab that targets this biomarker signaled a revolutionary turning point in treatment of metastatic gastric cancer. Many studies about targeted agents for gastric cancer have been attempted. Among them, ramicirumab, a monoclonal antibody that targets vascular endothelial growth factor receptor-2 (VEGFR-2), and apatinib, a tyrosine kinase inhibitor (TKI) that targets VEGFR2, have shown to improve the survival rates in advanced gastric cancer patients, for whom previous therapies had failed; hence, they are expected to be accepted as one of the standard therapies for advanced gastric cancer.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.368-374
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• 2008

Dry formulation is a limiting step for successful development of microbial bio-pesticides with the antagonistic Gram-negative bacteria because their survival rates are too low during drying and storage. The high concentration of sodium chloride (NaCl) in culture medium that induces osmolyte in bacterial cells is known to increase of survival rate during drying in many Gram-negative bacteria. Effect of NaCl on survival of antagonistic non-pathogenic Erwinia carotovora subsp. carotovora 9-3 (Ecc 9-3) during drying and storage was studied. Growth rate of Ecc 9-3 was not much different up to 0.5 M NaCl in NB while it was lower significantly with 0.7 M NaCl. Survival rates were twice and 3 times higher with 0.5 M NaCl than with no additional NaCl during drying at room temperature and freeze-drying, respectively. Survival rate was also higher with high NaCl in culture medium during storage after drying. It was not much different on storage at $4^{\circ}C$ both of drying at room temperature and freeze-drying. However, the survival rate was higher on storage at $27^{\circ}C$ and $37^{\circ}C$ with high NaCl concentration. Among the additives tested, lactose affects most to survival rate both of drying at room temperature and freeze-drying, and dextrin influenced significantly to survival rate of drying at room temperature.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.219-230
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• 2020

This study was conducted to determine the optimum medium and humidification period for the strawberry (Fragaria × ananassa Duch. cv. Maehyang) cutting seedling production. The cuttings were planted in coir (CO), rockwool (RW), phenolic foam (PF), and organic foam medium (OFM) with fogging treatment in 0, 3, 6, 9, or 12 days on February, 2019. And, as the field verification examination research, cuttings were planted in CO, RW, PF, and OFM, with misting treatment in 0, 6, 9, 12, or 15 days on June, 2019. In fogging treatments, rooting and survival rates of seedlings tended to increase with longer fogging periods, and rooting and survival rates were showed significantly higher in CO medium with more than 9 days of fogging periods. In misting treatments, rooting rate was significantly higher in CO and RW medium with more than 9 days of misting periods, and survival rate was significantly higher with more than 12 days of misting periods. There was no significantly difference by growth medium and humidification period in shoot and root growth. Therefore, when considering the rooting and survival rate the CO medium with 9 days of humidification period could be beneficial for the production of the 'Maehyang' strawberry cutting seedlings.