• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.100-109
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• 2006

This study evaluated the effects of water velocity, substrates, and phosphorus concentrations on the growth of filamentous periphytic algae (FPA) in the two types of artificial channel systems using treated wastewater. Controlled parameters included 5 ${\sim}$ 15 cm $s^{-1}$ for the water velocity; 10 and 20 mm wire meshes, natural fiber net, gravel and tile for the substrates: and 0.05 ${\sim}$ 1.0 mgP $L^{-1}$ for the P concentration. Algal growth rate of FPA was compared using both chi. a and dry weight change with time. Under the controlled water velocity range, the growth of FPA increased with the velocity, but the maximum growth rate was shown in the velocity of 10 cm $s^{-1}$. The substrate that showed the maximum growth of FPA differed between the artificial channel and indoor channel, due to the influence of suspended matters which caused the clogging of the meshed substrates. Under the controled range of P concentration, the growth rates of all three FPA species (Spirogyra turfosa, Oedogonium fovelatum, Rhizoclonium riparium) increased with the P increase, but they showed the differential growth rates among different P concentrations. The results of this study suggest that under the circumstance having an large amount of nutrients FPA develop the biomass rapidly and that even a little increase over the threshold velocity causes the detachment of filamentous periphytic algae. Thus, FPA dynamics in eutrophic streams, such as those receiving treated wastewater, seem to be sensitive to the water velocity. On the other hand, detached algal filaments could deteriorate water quality and ecosystem function in receiving streams or down-stream, and thus they need to be recognized as an important factor in water quality management in eutrophic streams.

• Composites Research
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• v.15 no.4
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• pp.23-31
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• 2002

The two dimensional size effect of specimen gauge section ($length{\;}{\times}{\;}width$) was investigated on the compressive behavior of a T300/924 $\textrm{[}45/-45/0/90\textrm{]}_{3s}$, carbon fiber-epoxy laminate. A modified ICSTM compression test fixture was used together with an anti-buckling device to test 3mm thick specimens with a $30mm{\;}{\times}{\;}30mm,{\;}50mm{\;}{\times}{\;}50mm,{\;}70mm{\;}{\times}{\;}70mm{\;}and{\;}90mm{\;}{\times}{\;}90mm$ gauge length by width section. In all cases failure was sudden and occurred mainly within the gauge length. Post failure examination suggests that $0^{\circ}$ fiber microbuckling is the critical damage mechanism that causes final failure. This is the matrix dominated failure mode and its triggering depends very much on initial fiber waviness. It is suggested that manufacturing process and quality may play a significant role in determining the compressive strength. When the anti-buckling device was used on specimens, it was showed that the compressive strength with the device was slightly greater than that without the device due to surface friction between the specimen and the device by pretoque in bolts of the device. In the analysis result on influence of the anti-buckling device using the finite element method, it was found that the compressive strength with the anti-buckling device by loaded bolts was about 7% higher than actual compressive strength. Additionally, compressive tests on specimen with an open hole were performed. The local stress concentration arising from the hole dominates the strength of the laminate rather than the stresses in the bulk of the material. It is observed that the remote failure stress decreases with increasing hole size and specimen width but is generally well above the value one might predict from the elastic stress concentration factor. This suggests that the material is not ideally brittle and some stress relief occurs around the hole. X-ray radiography reveals that damage in the form of fiber microbuckling and delamination initiates at the edge of the hole at approximately 80% of the failure load and extends stably under increasing load before becoming unstable at a critical length of 2-3mm (depends on specimen geometry). This damage growth and failure are analysed by a linear cohesive zone model. Using the independently measured laminate parameters of unnotched compressive strength and in-plane fracture toughness the model predicts successfully the notched strength as a function of hole size and width.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.1
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• pp.43-56
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• 2012

Objective : In this study, we assessed the anti-bacterial effects and epidermal permeability barrier function of red onion juice comparing to yellow onion juice and $Houttuynia$ $cordata$ extract $in$ $vitro$. Methods : 3types of red and yellow onion juice were prepared as antibacterial agent candidates with Houttuynia cordata hot water extract using 4 different bacterial strains ($Escherichia$ $coil$, $Salmonella$ $enterica$ $subsp.$ $enterica$, $Staphylococcus$ $epidermidis$, $Staphylococcus$ $aureus$ $subsp$) by colony counting method. The expression of filaggrin, a marker of keratinocyte differentiation, and serine palmitoyl transferase (SPT), a marker of the formation of the stratum corneum lipid barrier, in human HaCat keratinocytes were analyzed using HaCaT cell line. The expression of COX-2 and AP-1 which is a factor of COX-2 transcription were also analyzed by western blotting method. Results : There was detectable anti-bacterial effects on $Staphylococcus$ $epidermidis$, $Staphylococcus$ $aureus$ $subsp$ among 1%, 5%, 10% extracts of yellow and red onion.(81%-100%) The bacteriocidal effects were not shown on $Escherichia$ $coil$, $Salmonella$ $enterica$ $subsp.$ $enterica$ among $Houttuynia$ $cordata$, yellow onion and red onion extracts. The in vitro results showed the concentration-dependent effects on the expression of both filaggrin and SPT in HaCat cells among 0.01%, 0.05%, 0.1%, 0.5% extracts in Houttuynia cordata and red onion, reflecting the notion that $Houttuynia$ $cordata$ and red onion can induce epidermal keratinocyte differentiation and improve the recovery of skin barrier functions. The concentration-dependent effects also have been shown on the expression of both COX-2 and AP-1 among 0.01%, 0.05%, 0.1%, 0.5% extracts in $Houttuynia$ $cordata$ and red onion, while slight effect in yellow onion. Conclusion : Red onion juice could be a potential candidate enhanser for the skin care and cosmetology.

• Journal of Science Education
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• v.37 no.1
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• pp.142-156
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• 2013

The purpose of this study was to analyze observation characteristics through eye movement according to cognitive style. For this, developed observation task that can be shown the difference between wholistic cognitive style group and analytic cognitive style group, measured eye movement of university students who has different cognitive style, as given observation task. It is confirmed the difference between two cognitive style groups by analysing gathered statistics and visualization data. The findings of this study were as follows; First, Compared observation sequence and pattern by cognitive style, analytic cognitive style group is concerned with spider first and moving on surrounding environment, whereas wholistic cognitive style group had not fixed pattern as observing spider itself and surrounding area of spider alternately or looking closely on particular part at first. When observing entire feature and partial feature, wholistic cognitive style group was moving on Fixation from outstanding factor without fixed pattern, analytic cognitive style had certain directivity and repetitive investigation. Second, compared the ratio of observation, analytic cognitive style group gave a large part to spider the very thing, wholistic cognitive style group gave weight to surrounding area of spider, and analytic group shown higher concentration on observing partial feature, wholistic cognitive style group shown higher concentration on observing wholistic feature. Wholistic cognitive style group gave importance to partial features in surrounding area, and wholistic feature of spider than analytic cognitive style group, analytic cognitive style group was focus on partial features of spider than wholistic cognitive style group. Through the result of this study, there are differences of observing time, frequency, object, area, sequence, pattern and ratio from cognitive styles. It is shown the reason why each student has varied outcome, from the difference of information following their cognitive style, and the result of this study help to figure out and give direction to what observation fulfillment is suitable for each student.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.664-672
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• 2012

As an artificial light source, light-emitting diode (LED) with a short wavelength range can be used in closed-type plant production systems. Among various wavelength ranges in visible light, individual light spectra induce distinguishing influences on plant growth and development. In this study, we determined the effects of monochromatic LEDs on leaf shape index, growth and the accumulation of phytochemicals in a red leaf lettuce (Lactuca sativa L. 'Sunmang') and a green leaf lettuce (Lactuca sativa L. 'Grand rapid TBR'). Lettuce seedlings grown under normal growing conditions ($20^{\circ}C$, fluorescent lamp + high pressure sodium lamp, $130{\pm}5{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod) for 18 days were transferred into incubators at $20^{\circ}C$ equipped with various monochromatic LEDs (blue LED, 456 nm; green LED, 518 nm; red LED, 654 nm; white LED, 456 nm + 558 nm) under the same light intensity and photoperiod ($130{\pm}7{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod). Leaf length, leaf width, leaf area, fresh and dry weights of shoots and roots, shoot/root ratio, SPAD value, total phenolic concentration, antioxidant capacity, and the expression of a key gene involved in the biosynthesis of phenolic compounds, phenylalanine ammonia-lyase (PAL), were measured at 9 and 23 days after transplanting. The leaf shape indexes of both lettuce cultivars subjected to blue or white LEDs were similar with those of control during whole growth stage. However, red and green LEDs induced significantly higher leaf shape index than the other treatments. The green LED had a negative impact on the lettuce growth. Most of growth characteristics such as fresh and dry weights of shoots and leaf area were the highest in both cultivars subjected to red LED treatment. In case of red leaf lettuce plants, shoot fresh weight under red LED was 3.8 times higher than that under green LED at 23 days after transplanting. In contrast, the accumulation of chlorophyll, phenolics including antioxidants in lettuce plants showed an opposite trend compared with growth. SPAD value, total phenolic concentration, and antioxidant capacity of lettuce grown under blue LED were significantly higher than those under other LED treatments. In addition, PAL gene was remarkably activated by blue LED at 9 days after transplanting. Thus, this study suggested that the light quality using LEDs is a crucial factor for morphology, growth, and phytochemicals of two lettuce cultivars.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.51-57
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• 2018

The objective of this study was to identify beauty food activity of Polygala japonica Houtt., which were widely used as a folk medicinal plant to treat inflammatory diseases. Both hot water and 50% ethanol extract of P. japonica Houtt. were evaluated for their anti-oxidant, whitening, anti-wrinkle and anti-inflammatory effect based on their phenolic concentration. To measure anti-oxidant activity, four experiments were carried out. 1,1-diphenyl-3-picrylhydrazyl, 2,2-azinobis (3-ethylbenzothia-zoline-6-sulfonic acid) and thiobarbituric acid reactive substances all showed more than 80% efficacy in both hot water and 50% ethanol extract of P. japonica Houtt. and likewise antioxidant protection factor value more than 2. To investigate the whitening effect of P. japonica Houtt., the inhibition effect of tyrosinase on hot water and 50% ethanol extract was inhibited by 12.46 and 22.10%, respectively. To examine the anti-wrinkle effect, the inhibition effect of elastase and collagenase on hot water and 50% ethanol extract were inhibited by 28.28, 58.36% and 59.73, 78.90% respectively. To investigate the anti-inflammatory effect and moisturizing effect by hyaluronidase inhibitory effect, hot water and 50% ethanol extract were 35.65 and 86.80%, respectively. The result of all the above experiments show values at a concentration of $200{\mu}g/mL$, and based on these experimental results, P. japonica Houtt. can be expected as a functional material in beauty foods.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.67-73
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• 2008

The dissipation patterns of a boscalid in cucumber under greenhouse condition was investigated to establish pre-harvest residue limit (PHRL) and biological half-life. Initial concentration of boscalid in cucumber at standard application rate was $7.29\;mg\;kg^{-1}$ and decreased to $0.04\;mg\;kg^{-1}$ after 15 days with half-life of 1.9 day, while the initial concentration was $14.69\;mg\;kg^{-1}$ and decreased to $0.11\;mg\;kg^{-1}$ after same period with half lift of 2.0 day at double application rate. PHRL was suggested by prediction curve derived from the decay curve of boscalid at double rate treatment. For example, $10.39\;mg\;kg^{-1}$ was calculated for 10 days before harvest, and $1.73\;mg\;kg^{-1}$ for 5 days. Dilution effect was major factor far the decrease of boscalid residue due to fast increasement of weight of cucumber during cultivation. Final residues level of boscalid was predicted based on the dissipation curve and guideline on safe use, when boscalid was used to control powdery mildew and gray mold. At standard rate application, $1.26\;mg\;kg^{-1}$ and $1.33\;mg\;kg^{-1}$ were calculated as final residue levels for control powdery mildew and gray mold, respectively, which are above the MRL(Meximum Residue Limit).

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.35-47
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• 2014

The purpose of the study is to evaluate the pollution level (gaseous and particle phase) in the public facilities for the PAHs, non-regulated materials, forecast the risk level by the health risk assessment (HRA) and propose the guideline level. PAH assessments through sampling of particulate matter of diameter < 2.5 ${\mu}m$ ($PM_{2.5}$). The user and worker exposure scenario for the PAHs consists of 24-hour exposure scenario (WIES) assuming the worst case and the normal exposure scenario (MIES) based on the survey. This study investigated 20 PAH substances selected out of 32 substances known to be carcinogenic or potentially carcinogenic. The risk assessment applies major toxic equivalency factor (TEF) proposed from existing studies and estaimates individual Excess Cancer Risk (ECR). The study assesses the fine dusts ($PM_{2.5}$) and the exposure levels of the gaseous and particle PAH materials for 6 spots in each 8 facility, e.g. underground subway stations, child-care facilities, elderly care facilities, super market, indoor parking lot, terminal waiting room, internet caf$\acute{e}$ (PC-rooms), movie theater. For internet caf$\acute{e}$ (PC-rooms) in particular, that marks the highest $PM_{2.5}$ concentration and the average concentration of 10 spots (2 spots for each cafe) is 73.3 ${\mu}g/m^3$ (range: 6.8-185.2 ${\mu}g/m^3$). The high level of $PM_{2.5}$ seen in internet cafes was likely due to indoor smoking in most cases. For the gaseous PAHs, the detection frequency for 4-5 rings shows high and the elements with 6 rings shows low frequency. For the particle PAHs, the detection frequency for 2-3 rings shows low and the elements with 6 rings show high frequency. As a result, it is investigated that the most important PAHs are the naphthalene, acenaphthene and phenanthrene from the study of Kim et al. (2013) and this annual study. The health risk assessment demonstrates that each facility shows the level of $10^{-6}-10^{-4}$. Considering standards and local source of pollution levels, it is judged that the management standard of the benzo (a)pyrene, one of the PAHs, shall be managed with the range of 0.5-1.2 $ng/m^3$. Smoking and ventilation were considered as the most important PAHs exposure associated with public facility $PM_{2.5}$. This study only estimated for inhalation health risk of PAHs and focused on the associated cancer risk, while multiple measurements would be necessary for public health and policy.

• Food Science and Preservation
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• v.22 no.4
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• pp.613-621
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• 2015

In this study, the anti-oxidant and anti-inflammatory activities of water extract (ASSW) and 70% ethanol extract (ASSE) of Allium sativum L. stems were investigated using Raw 264.7 cells induced by lipopolysaccharide (LPS). ABTS radical scavenging activities of ASSW and ASSE at $1000{\mu}g/mL$ concentration were 96.9% and 97.8%, respectively. In order to investigate the potential anti-inflammatory effects of ASSW and ASSE, nitric oxide (NO), pro-inflammatory cytokines, interleukin-6 (IL-6), and tumor necrosis factor including ${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and prostaglandin-E2 (PGE2) were measured. ASSW and ASSE at $100{\mu}g/mL$ concentration showed inhibitory effects against NO production by 18% and 23%, respectively. Production of IL-$1{\beta}$ and IL-6 after treatment with ASSW and ASSE at $100{\mu}g/mL$ decreased by approximately 28% and 15% for ASSW and 17% and 12% for ASSE, respectively. In addition, production of TNF-${\alpha}$ after treatment of $100{\mu}g/mL$ of ASSW and ASSE decreased by 24% and 23%, respectively. In addition, the treatment of $100{\mu}g/mL$ of ASSW and ASSE showed inhibitory expressions against PGE2 by 45.47% and 33.87%, respectively. These results suggested that ASSE showed greater inhibitory activity than that of the ASSW by the suppression of inflammatory mediators, including NO, IL-6, TNF-${\alpha}$ and PGE2 production, and the expressions of iNOS and COX-2 in macrophages. In conclusion, ASSW and ASSE may have some ancillary effects on inflammatory factors as potential anti-inflammatory agents.

• Korean Journal of Medicinal Crop Science
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• v.16 no.5
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• pp.349-355
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• 2008

Anticancer and immuno-modulatory activities of methanol extracts from different parts, bark, wood and leaf, of Cornus macrophylla Wall. were investigated in this study. All extracts at a concentration of 1.0mg/ml showed relativity low cytotoxicities on human normal kidney cell (HEK293) by approximately 25%. Bark extract of C. macrophylla showed the highest anticancer activity on human lung cancer cell line (A549) and human breast cancer cell line (MCF-7) by 57.4% and 58.7%, respectively, at a concentration of 1.0mg/ml. All extracts enhanced the growth of human B and T cells, showing 38.7% and 65.9% increase compared to control, respectively, by 5 days incubation with bark extract. The secretions of interleukin 6 (IL6) and tumor necrosis factor alpha (TNF-$\alpha$) from human B and T cells were significantly increased by extracts, especially bark extract. B or T cell medium, which contains cytokines (IL 6 and TNF-$\alpha$) secreted by bark extract treatment for 5 days, time-dependently enhanced the growth of NK-92MI cells with the maximal effect at 5th day of incubation. These results suggest that C. macrophylla, especially bark, has the potential for anticancer and immuno-modulatory activities.