• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.2
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• pp.129-136
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• 2007

To investigate the effect of large patch infection on oxidative stress induction, growth, $H_2O_2$ concentration and lipid peroxidation were compared between pathogen-infected and healthy (control) zoysiagrass. The sampling for leaves and roots were carried out every 2 days for a period of 6 days. Pathogen-infection increased root mortality by 30% compared to control. Dry mass was not significantly affected by pathogen-infection until day 4, but significant decreases in both leaves (-14%) and roots (-20%) were observed at day 6. The $H_2O_2$ concentration in pathogen-infected leaves rapidly increased within the first 2 days(+28%) and then slightly decreased. The increase of $H_2O_2$ in pathogen-infected roots was distinct, showing 1.7-fold higher level than control at day 6. The extent of lipid peroxidation caused by pathogen-infection continuously increased for the first 4 days. This was then stagnated until day 6. In roots, the significant increase of lipid peroxidation was observed only at day 2. These results indicate that large patch-infection induces oxidative stress, and that the oxidative stress responsive pattern was plant organ specific.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.1
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• pp.51-64
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• 2011

Carbon dioxide Capture and Storage (CCS) is one of the key players in greenhouse gas (GHG) reduction portfolio for mitigating climate change. CCS makes simultaneously it possible not only to reduce a huge amount of carbon dioxide directly from the emission sources (e.g., coal power plant) but also to maintain the carbon concentrated-energy and/or industry infrastructure. Internationally, the United Nations Framework Convention on Climate Change (UNFCCC) is dealing the agenda for considering the possibility of including CCS project as one of Clean Development Mechanism (CDM) projects. Despite its usefulness, however, there are the controversies in including CCS as the CDM project, whose issues include i) non-permanence, including long-term permanence, ii) measuring, reporting and verification (MRV), iii) environmental impacts, iv) project activity boundaries, v) international law, vi) liability, vii) the potential for perverse outcomes, viii) safety, and ix) insurance coverage and compensation for damages caused due to seepage or leakage. In this paper, those issues in considering CCS as CDM are summarized and analyzed in order to suggest some considerations to policy makers in realizing the CCS project in Korea in the future.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.2
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• pp.118-134
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• 2015

An analytical solution of dynamic responses for seabed in shallow, finite and infinite thicknesses has been developed under flow and standing wave coexisting field at a constant water depth condition. To do this, based on the Biot's consolidation theory, the seabed is assumed as a porous elastic media with the assumptions that pore fluid is compressible and Darcy law governs the flow. The developed analytical solution is compared with the previous results and is verified. Using the analytical solution the deformation, pore pressure, effective and shear stresses of seabed are examined under various given values of flow velocity, incident wave period and seabed thickness. From this study, it is confirmed that the seabed response is quite different depending on consideration of flow, which causes changing period and length of incident and reflection waves.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.412-419
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• 1988

Cold-induced sterility is a problem of rice (Oryza sativa L.) production in temperate regions and high elevation tropics. The present study was conducted to measure combining ability, determine character associations. and to evaluate effectiveness of F$_2$selection for tolerance to this type of cold injury. The F$_1$, F$_2$, F$_3$ and reciprocal backcross F$_1$ populations of a nine-parent diallel were grown at Davis, California. a relatively cool location for rice. Additive genetic variance was predominant but some non -additive genetic variance existed for cold tolerance. Good general combining ability (GCA) was generally associated with the cold tolerant parents, 'M-201', and 'L-201', and poor GCA with the most susceptible parent. 7703008. Sterility was positively correlated with late heading. negatively with mature plant height. and negatively with spikelet number. Of the three agronomic characters, heading date had the greatest influence on sterility. Selection of F$_2$'s in seven crosses involving M-101, the most cold-tolerant parent, was effective for increasing cold tolerance. Realized heritability estimates for cold tolerance averaged 0.53, and observed selection response for cold-induced sterility averaged -9.4 percentage points.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.331-335
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• 1999

The present study was carried out to investigate the combined effect of radiation and photoperiod (PP) regimes on Tradescantia 4430 somatic cell mutations. Potted plants were irradiated with 0.3, 0.5 and 1.0 Gy of gamma radiation from 60Co source. The plants irradiated only with gamma radiation were used as control group (CT). The somatic cell mutation rate in 0.5 Gy irradiated CT and PP20 group started to increase on the 6th day and reached a maximum value on the l0th day and 9th day after irradiation while the rate in the experimental group under 4 hours of photoperiod a day (PP4) started to increase on the l0th day and reached a maximal value on the 16th day post-irradiation. The slope of dose-response curve in CT was 5.99 ($r^2$=0.99), while it was 6.93 ($r^2$=0.98) in PP20 and 11.74 ($r^2$=0.99) in PP4, respectively. The biological efficacy of radiation in the induction of pink mutation increased by 15.7% in PP20 and 95.9 % in PP4, respectively. It is suggested that photoperiod regimes unfavorable to the plant have an additive effect on radiation-induced mutations and a delaying or inhibiting effect on cell damage repair, as well.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.2
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• pp.163-170
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• 2004

A new oil crop chufa(Cyperus esculentus var. sativus) was studied to evaluate the yield potential of tuber and productivity of leaf as a new forage crop resources. Response to nitrogen fertilizer was not clear, showing low yield over 10kg/l0a of nitrogen application. Tuber yield was higher at 50cm $\times$ 15cm and 50cm$\times$20cm of planting population of tuber. Planting at early May showed high tuber yield, and sprouting tuber planting could not increased the tuber yield. The plant height of Chufa is 126cm, and the number of tiller per $\m^2$ are 671. It is moderate to lodging, but susceptable according to the amount of field products. Fresh forage and dry matter yield of above ground of chufa were 2,135kg/10a, and 590kg/l0a, respectively. The contents of crude protein, ether extract, fiber, ash, and acid detergent fiber are 24.8%, 8.1%, 38%, 64.4%, 52.8%, and 55.9%, respectively. It was considered that the nutritive value of chufa leaf in maturing stage was so good as rice straw.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.777-782
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• 2010

This research tested five modified Hoagland solutions for proper fertility management of nitrogen in 'Seolhyang' strawberry cultivations. The changes of nutrient solutions were in total nitrogen concentrations ($meq{\cdot}L^{-1}$) such as 0 (${NO^-}_3$), 2.5 (${NO_3}^-$), 5 (${NO_3}^-$), 10 ($7.5{NO_3}^-$ + $2.5{NH_4}^+$) and 15 ($10{NO_3}^-$ + $5{NH_4}^+$). The fresh weight and $NO_3$-N concentrations in petiole sap responded to the elevated nitrogen concentrations in fertilizer solution in quadratic (y=7.10+2.668x-$0.115x^2$, $R^2=0.7983^{***}$) and linear (y=26.14+5.245x, $R^2=0.6083^{***}$), respectively. The dry weight and N content of the above ground plant tissue responded to the elevated nitrogen in quadratic (y=2.140+0.492x-$0.022x^2$, $R^2=0.6110^{***}$) and linear (y=0.569+0.033x, $R^2=0.6952^{***}$), respectively. In our experiment the solution with $5meq{\cdot}L^{-1}$ of ${NO_3}^-$ showed positive results in both dry and fresh weight productions. However, a future research about modification of this solution and growth and nutrient uptake response is necessary to achieve better growth of 'Seolhyang' strawberry.

• Journal of Life Science
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• v.24 no.1
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• pp.8-13
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• 2014

The moringa (Moringa oleifera Lam.) plant is used as food and as an anti-allergic agent. In this study, we studied the inhibitory effect of moringa root extract on the expression of PMA-induced matrix metalloproteinase-9 (MMP-9), which is the main factor implicated in the invasion and metastasis of cancer cells in MCF-7 cells. At first, various moringa extracts were examined in the MCF-7 cells. Both moringa root extract and leaf extracts inhibited PMA-induced MMP-9 activity, but the root extract suppressed PMA-induced MMP-9 activity to a greater extent than the leaf extract. The moringa root extract also inhibited PMA-induced MMP-9 protein expression and cell invasion. According to RT-PCR, the treatment of the MCF-7 cells with moringa root extract decreased levels of PMA-induced MMP-9 mRNA expression, but not the expression of TIMP-1 and -2, indicating that moringa root extract prevents the transcription of MMP-9 in response to PMA. In addition, moringa root extract specifically suppressed the phosphorylation of ERK/JNK, but not p38. We suggest that moringa root extract abolishes MMP-9 activity/expression through ERK/JNK. In conclusion, moringa root extract suppressed PMA-induced MMP-9 activity/expression by inhibiting the phosphorylation of ERK/JNK in MCF-7 cells. These results indicate that moringa root extract may be a potential antimetastatic and anti-invasive agent. Future clinical research is needed on the anticancer properties of moringa root extract.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.111-126
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• 2008

The purpose of this study was to examine the dietary habits and nutrient intakes of school-aged children participating in extracurricular classes, to with regards to class schedule. Three-hundred and two students from Seoul were selected and classified into two groups. One group attended extracurricular classes less than 12.43 hours per week, which was determined as the average number of hours per week(AELT, n=147). The other group attended extracurricular classes more than 12.43 hours per week(AEMT, n=155). The average student age in both the AELT and AEMT groups was 11.9 years, respectively. In terms of height and weight, there were no significant differences between the two groups. AELT received significantly more hours of sleep than AEMT(p<0.01), and there were significantly more responses with regard to lack of sleep in the AEMT group than in the AELT group(p<0.05). In a survey on 17 clinical symptoms regarding health, the AEMT group had significantly higher response rates than the AELT group in the following sections: no appetite (p<0.001), dizziness(p<0.001), headache(p<0.01), tiredness(p<0.01), cold symptoms(p<0.05), and sore eyes(p<0.05). Meal time irregularity was significantly higher than AEMT than in AELT(p<0.05). Approximately 50% of the subjects were picky eaters, and 40% and 20% skipped breakfast or dinner, respectively. The average energy intakes for AELT and AEMT were 2122.2 kcal and 2061.5 kcal, respectively, and there was no significant difference between the two groups. AEMT consumed significantly lower quantities of protein, animal fat, vitamin $B_6$, calcium, and phosphorus(each p<0.05) as compared to the AELT group. Beverage intake was significantly higher in AEMT than AELT(p<0.05). The number of hours in extracurricular classes showed a significant negative correlation with the intakes of protein, animal protein, animal fat, vitamin $B_6$, folate, calcium, plant calcium and phosphorus(each p<0.05). The number of hours in extracurricular classes also showed a significant negative correlation with soy foods intake(p<0.05). These results suggest that continuous and systematic nutritional education should be performed in order to prevent and improve the unbalanced diets and problematic of dietary habits that may result in students due to attendance in extracurricular classes.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.627-636
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• 2020

Background: Cultivation of medicinal crops, which synthesize hundreds of substances for curative functions, was focused on the synthesis of secondary metabolites rather than biomass accumulation. Nutrition is an important restrict factor for plant growth and secondary metabolites, but little attention has been given to the plasticity of nutrient uptake and secondary metabolites synthesis response to soil nitrogen (N) change. Methods: Two year-field experiments of Sanqi (Panax notoginseng), which can synthesize a high level of saponin in cells, were conducted to study the effects of N application on the temporal dynamics of biomass, nutrient absorption, root architecture and the relationships between these parameters and saponin synthesis. Results: Increasing N fertilizer rates could improve the dry matter yields and nutrient absorption ability through increasing the maximum daily growth (or nutrient uptake) rate. Under suitable N level (225 kg/ha N), Sanqi restricted the root length and surface and enhanced the root diameter and N uptake rate per root length (NURI) to promote nutrient absorption, but the opposite status of Sanqi root architecture and NURI was found when soil N was deficient. Furthermore, increasing N rates could promote the accumulation of saponin in roots through improving the NURI, which showed a significant positive relationship with the content of saponin in the taproots. Conclusion: Appropriate N fertilizer rates could optimize both root architecture and nutrient uptake efficiency, then promote both the accumulation of dry matter and the synthesis of saponins.