• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.336-343
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• 2003

Two types of statistical models, simple and multivariate log linear models, were studied for continuity simulation and trend analysis of water qualities in incoming flows to Lake Paldang. Water quality is a function of one independent variable (flow) in the simple log linear model, and of three different variables (flow, time, and seasonal cycle) in multivariate model. The independent variables act as surrogate variables of water quality in both models. The model coefficients were determined by the monthly data. The water qualities included 5-day Biochemical Oxygen Demand ($BOD_5$), Total Nitrogen (TN), and Total Phosphorus (TP) measured from 1995 to 2000 in the South and the North branches of Han River and the Kyoungan Stream. The results indicated that the multivariate model provided better agreements with field measurements than the simple one in a31 attempted cases. Flow dependency, seasonality, and temporal trends of water quality were tested on the determined coefficients of the multivariate model. The test of flow dependency indicated that BOD concentrations decreased as the water flow increased. In TN and TP concentrations, however, there were no discernible flow effects. From the temporal trend analyses, the following results were obtained: 1) no trends on BOD at all three upstreams, 2) increase on TN at the South Branch and the Kyoungan Stream, 3)decrease on TN at the North Branch,4) no trends on TP at the North and the South Branches and 5) increase on TP at the Kyoungan Stream by 3 to 8% per years. The seasonality test showed that there were significant seasonal variations in all three water qualities at three incoming flows.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.319-327
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• 2014

Understanding and quantifying of carbon storage in ecosystem is very important factor for predicting change of global carbon cycle under the global climate change. We estimated total ecosystem carbon in Gyeryongsan National Park with naturally well preserved ecosystem in Korea. Vegetation of Gyeryongsan National Park was classified with mainly four communities with Quercus mongolica (1,743.5 ha, 38.0%), Quercus variabilis (1,174.0 ha, 25.6%), Quercus serrata (971.9 ha, 21.2%), Pinus densiflora (695.2 ha, 15.2%). Biomass and soil carbons were calculated from biomass allometric equations based on the DBH and carbon contents of soil and litter collected in quadrat in each community. The tree biomass carbon was in Quercus variabilis ($130.1tCha^{-1}$), Pinus densiflora ($111.1tCha^{-1}$), Quercus mongolica ($76.2tCha^{-1}$), Quercus serrata ($39.0tCha^{-1}$). Soil carbon storage was in Quercus mongolica ($159.7tCha^{-1}$), Quercus serrata ($121.0tCha^{-1}$), Pinus densiflora ($110.5tCha^{-1}$), Quercus variabilis ($90.8tCha^{-1}$). Ecosystem carbon storage was Pinus densiflora ($239.9tCha^{-1}$), Quercus mongolica ($235.9tCha^{-1}$), Quercus variabilis ($226.0tCha^{-1}$), Quercus serrata ($165.9tCha^{-1}$), total amount was $867.7tCha^{-1}$. The area of each vegetation carbon storage was Quercus mongolica ($411,200tCha^{-1}$), Quercus variabilis ($265,300tCha^{-1}$), Pinus densiflora ($166,800tCha^{-1}$), Quercus serrata ($161,200tCha^{-1}$) and the total ecosystem carbon amount estimated $1,045,400tCha^{-1}$ at Gyeryongsan National Park. Theses results indicate that different in naturally well preserved ecosystem.

• Journal of Life Science
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• v.22 no.5
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• pp.642-649
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• 2012

The southern coast of Korea is important for the ark shell ($Scapharca$ $broughtonii$) aquaculture, but the productivity was rapidly reduced during the previous decade by mass mortality. To overcome this economic loss, investigations only focused on environmental factors, and microbiological researches were performed insufficiently. In this study, two sites (Gangjin and Jinhae bay) were selected for their high and low rate of mortality, respectively, and the existence of microflora from underwater sediments in the bodies of $S.$ $broughtonii$ was analyzed. We screened the whole body of each sample and chose unique colonies, which exhibit alpha- and beta-hemolytic activity, for identification. The microflora in $S.$ $broughtonii$ was less variable than sediments, and restricted species were isolated. We identified 17 genera of 88 species and 16 genera of 64 species from the two bays, respectively. A major proportion was comprised of $Bacillus$ species, with the $Bacillus$ $cereus$ group being the most common species among the $Bacillus$ strains, while $Paenibacillus$, $Lynsilbacillus$, and $Vibrio$ species were the second most abundant species. At the genus level, there were no significant microbial differences between the two coastal regions. 64 species were isolated from rare site (Jinhae bay), but more species (88) with greater variety were isolated from the frequent site (Gangjin bay). Therefore, it was assumed that the cause of mass mortality lay in the difference in specie-level diversity, and conducting investigations on the diagnosis of pathogenic species by challenging tests using isolated unique species.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.565-572
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• 2016

This study was conducted to evaluate the quality of barley (Huinchalssalbori) and domestic wheats (Keumkangmil, Baegjoongmil, Jogyeongmil). The pH and total acidity of mixed Makgeolli were 4.04~4.12% and 0.94~1.06%, respectively. The total acidity, sugar and alcohol contents of Makgeolli, but not pH, varied significantly by wheat cultivar (p<0.05). In terms of color values, the L-value of Baegjoongmil, a-value and b-value of Keumkangmil were highest. The reducing sugar contents was approximately 5.65~7.85 mg/mL, and those of Jogyeongmil and imported wheat were approximately 5.70 mg/mL lower. The yeast cell numbers did not differ significantly, with the exception of in the rice Makgeolli (p<0.05). Among the organic acids (citric, malic, pyruvic and lactic acids) in Makgeolli, citric acid was present at the highest concentration. Regarding the sensory characteristics of Makgeolli mixed with barley and wheat, taste and overall acceptability were highest in Baegjoongmil, and appearance and flavor were highest in Keumkangmil. The rice Makgeolli showed the lowest sensory values, with the exception of appearance. The results of this study suggest that mixing Makgeolli with barley and wheat is an expected to replace the wheat materials in the domestic wheat to be imported.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.206-211
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• 2009

In order to investigate the effects of elicitors on the growth and ginsenoside biosynthesis of ginseng hairy roots, we treated Panax ginseng hairy root with various concentrations of Haliotidis concha according to different time course. Haliotidis concha supplement increased the biomass and ginsenoside accumulation at 10 mg/L concentration. The growth rate of hairy root under a lighter concentration was greater than hairy root treated with a denser concentration. The highest content and productivity of ginsenosides appeared at 2 weeks after the treatment of 10 mg/L Haliotidis concha. The gene expression of squalene synthase, squalene epoxidase, dammarenediol synthase, cycloartenol synthase, $\beta$-amyrin synthase in hairy roots of ginseng were examined by RT-PCR. The Haliotidis concha treatment resulted in the obvious accumulation of the mRNA of triterpene biosynthesis in Panax ginseng hairy root as compared with the control. In this study, Haliotidis concha acts as a kind of elicitor for the production of ginsenosides.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.257-264
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• 2018

The recent global climate change induced the drought, flooding, and insect pest outbreaks. These caused the severe damage to crop yield in the domesticated field and occurrence change of insect pest species. The sap-sucking insect pest, aphids are common in soybean [Glycine max (L.) Merr.] and cause serious yield losses. Thus, developing resistance cultivars is promising and efficient strategy to prevent the significant yield losses by aphid and screening germplasm is the essential procedure to achieve this goal. We tried to establish a resistance test indicator for foxglove aphid, Aulacorthum solani (Kaltenbach), in soybean and found that plant damage degree or infested plant damage is most suitable one. Also we screened around 1,200 of soybean germplasm including wild and cultivated species for its resistance to foxglove aphid from the various origins, and 67 soybeans, including PI 366121, showed antixenosis resistance, 31 germplasms among 67 antixenosis germplasms were showed antibiosis to foxglove aphid with non-choice test. The identified foxglove aphid resistant soybean resources showed significantly low rate in survival test. Furthermore, resistance type, (i.e., antibiosis or antixenosis) of each candidate were varied. In this research, we established the screening index for foxglove aphid resistance in soybean, and identified the resistance varieties. This result could be useful resources in breeding for new foxglove aphid resistance soybean cultivars, and provide fundamental information to investigate the resistance mechanism in soybean.

• Science of Emotion and Sensibility
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• v.19 no.1
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• pp.95-110
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• 2016

Uncanny valley refers to the condition where the affinity of a human-like object decreases dramatically if the object becomes extremely similar to human, and has been hypothesized to derive from the cognitive load of categorical conflict against an uncanny object. According to the hypothesis, the present study ran an oddball task consisting of trials each displaying one among a non-human, human and uncanny face, and measured event-related potentials (ERPs) for each trial condition. In Experiment 1, a non-human face was presented in 80% of the trials (standard) whereas a human face for another 10% trials (target) and an uncanny face for the remaining 10% trials (uncanny). Participants' responses were relatively inaccurate and delayed in both the target and uncanny oddball trials, but neither P3 nor N170 component differed across the three trial conditions. Experiment 2 used 3-D rendered realistic faces to increase the degree of categorical conflict, and found the behavioral results were similar to Experiment 1. However, the peak amplitude of N170 of the target and uncanny trials were higher than the standard trials while P3 mean amplitudes for both the target and uncanny trials were comparable but higher than the amplitude for the standard trials. P3 latencies were delayed in the order of the standard, target, and uncanny trials. The changes in N170 and P3 patterns across the experiments appear to arise from the categorical conflict that the uncanny face must be categorized as a non-target according to the oddball-task requirement despite its perceived category of a human face. The observed increase of cognitive load following the added reality to the uncanny face also indicates that the cognitive load, supposedly responsible for the uncanny experience, would depend on the increase of categorical conflict information subsequent to added stimulus complexity.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.725-736
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• 2017

TThis study investigated the influence of AGH-Ringer (chelated organic minerals liquid fertilizer) on the growth, yield, and fruit quality of 'Jukhyang' strawberry in a hydroponic system. The results revealed that AGH-Ringer group led to significantly higher plant length than that of the control group, and that leaf length and leaf width increased with increasing leaf area. In addition, the fresh and dry weights of leaves and SPAD unit, which measures leaf color also showed a significant increase with AGH-Ringer. However, the length and dry weight of roots did not show significant differences when compared to the control group. In the fruit quality analysis, AGH-Ringer group did not show any difference in fruit length compared to the control group, but it increased both the fruit weight, which, along with the simultaneous increase in fruit width, increased the yield per strawberry. Furthermore, AGH-Ringer group strengthened the red skin color of the fruit, and resulted in significantly greater hardness than that of the control group, but did not have any effect on the soluble solid content and acidity. As shown in the results, the AGH-Ringer group resulted in lesser mineral content and lower to medium EC (electrical conductivity) in comparison to the inorganic mineral hydroponic fertilizer, which was used as a control. However, it increased the leaf growth, fruit weight, and yield, and improved the fruit quality by increasing the soluble solid content in the hydroponic system of 'Jukhyang' strawberry. Therefore, based on this study, AGH-Ringer is thought to be a more effective hydroponic fertilizer than the inorganic mineral hydroponic fertilizer. Moreover, the field experiment demonstrated that AGH-Ringer is a useful hydroponic fertilizer convenient for application in farms. This study also proved that AGH-Ringer is a fertilizer that can promote plant nutrition by controlling the salinity of the soil and facilitating the absorption of necessary minerals in future soil cultivation, thereby providing basic data for organic farming.

• Journal of Soil and Groundwater Environment
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• v.18 no.4
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• pp.19-31
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• 2013

To figure out the decay characteristics of naturally occurring radionuclides, eight sampled groundwaters from a monitoring borehole having high levels of uranium and radon concentrations in a two mica granitic area have analyzed by liquid scintillation counters (LSC) for over 1 year. In December 2011, three groundwater samples (DJ1, DJ2, DJ3) were obtained from each aquifer system located at -20 m, -40 m, -60 m of the monitoring borehole below the ground surface, respectively. Five samples (DJ4, DJ5, DJ6, DJ7, DJ8) were additionally gained from each aquifer positioned -20 m, -40 m, -60 m, -100 m, -105 m of the borehole in February 2012, respectively. Temporal variation characteristics of uranium and radon concentrations have showed over maximum 2.1 times and 1.4 times fluctuations of the values in the same sampling intervals over time, respectively. The intervals of -40 m and -105 m in the borehole have the highest values of uranium and radon concentrations, respectively. This may imply that the concentrations of naturally occurring radionuclides such as uranium and radon in groundwater have been changed over time and indicate that the qualities of groundwaters from the aquifers developed at each interval in the borehole are different each other. This discrepancy, moreover, could be caused by behaviour differences between uranium which is in ionic status having a half life of 4.6 billion years and is transported along with the flowing groundwater, and radon which is in gaseous status having a 3.82 day's half life in the aquifer systems. Physicochemical characteristics of groundwaters from the aquifer systems could be identified by the results of the on-situ measuring items such as pH and Eh, and the major ionic contents. The CPM values of eight groundwater samples analysed by LSC over one year have shown not to follow the theoretical decay curve of the radon. The CPM values of the samples have ranged from 2 to 7.5 after it had passed two months when the theoretical CPM values of the radon started zero since the initial analysis. Alpha and beta particle spectrums have shown the peaks of radium-226, however they have not revealed any peaks of radon and it's daughter products such as polonium-218 and 214, bismuth-214 for the late stage of the analysis. This implies that the groundwater from the borehole may contain radium-226 having a half life of 1,600 years which decays continuously.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.296-301
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• 2011

This study was to evaluate the growth potential of E. coli O157:H7 in lettuce leaf extracts and on lettuce leaf surface at various temperatures. The pathogen can survive and multiply in the extracts and leaf surface of lettuce. The population of E. coli O157:H7 in the lettuce extracts reached to 4.79 log CFU/mL at $37^{\circ}C$. The multiplication of pathogen in lettuce extracts initiated within 10 hours of inoculation over $15^{\circ}C$ conditions. And it can survive in the lettuce leaf extracts at $4^{\circ}C$ for 100 hours at least. And this pathogen can multiply on lettuce leaf surface and the population of pathogen on the lettuce leaf surface increased to 1.82 log CFU/g at $25^{\circ}C$. At $37^{\circ}C$, the pathogen density increased to 1.53 CFU/g within 3 days after inoculation. At all temperature, irrespective of the inoculation level, similar trends in growth of E. coli O157:H7 were observed. These results emphasize the growth potential of E. coli O157:H7 in lettuce leaf extract and on lettuce leaf surface. To reduce the risk of outbreak, it is important to maintain the cold chain system during storage before the consumption.