• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.108-114
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• 2015

Single - and combined effects of a domestic freshwater bivalve Unio douglasiae (7.6~8.6 cm in shell length) and zooplankton Daphnia magna (1~2 mm in body size) were examined to understand whether they inhibit the growth of harmful cyanobacterial bloom (i.e. Microcystis aeruginosa) in a eutrophic lake. The experiments were triplicated with twelve glass aquaria (40 L in volume); three aquaria without mussel and zooplankton, served as a control, three zooplankton aquaria (Z, density=40 indiv. $L^{-1}$), three mussel aquaria (M, density=0.5 indiv. $L^{-1}$), and three mussel plus zooplankton aquarium (ZM, density=40 indiv.Z $L^{-1}$ plus 0.5 indiv.M/L), respectively. Algal growth inhibition (%) calculated as a difference in the concentration of chlorophyll-a (Chl-a) before and after treatment. Chl-a in all aquaria decreased with the time, while a greatest algal inhibition was seen in the ZM aquaria. After 24 hrs of incubation, Chl-a concentration at the mid-depth (ca. 15 cm) in ZM aquaria reduced by 90.8% of the control, while 63.2% and 79.8% in Z and M aquaria, respectively. Interestingly, during the same period, the surface Chl-a was diminished by 51.9% and 65.4% relative to the control in Z and ZM aquaria, while 27.4% of initial concentration decreased in M aquarium, respectively. These results suggest that 1) this domestic freshwater filter-feeding bivalve plays a significant role in the control of cyanobacterial bloom (M. aeruginosa), and 2) the combination with zooplankton and mussel has a synergistic effect to diminish them, compared to the single treatment of zooplankton and mussel.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.1-6
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• 1986

This study was conducted to find out the effect of $SiO_2$ treatment on the $SiO_2$ concentration in guttation liquid, the amount of guttation liquid exudated from the margin of rice leaves, and the relationships between $SiO_2$ concentration in guttation liquid and foliar burn during the rice seedling stage, using two rice varieties;Nagdong-byeo (a Japonica) and Samgang-byeo (a - Indica - Japonica hybrid). Seedlings were cultivated in water solution and enveloped in polyvinyl case ($50cm{\times}150cm{\times}70cm$). $SiO_2$ treatment increased the amount of guttation liquid, the amount of guttation liquid (Nagdong-byeo:4.30mg/plant, Samgang-byeo:4.34mg/plant)) treated with 200ppm of $SiO_2$ was greater than any other level, decreased over 200ppm of $SiO_2$. $SiO_2$ concentration in guttation liquid was increased as application rates of $SiO_2$ increased, showing the positive correlation, and $SiO_2$ in guttation liquid/$SiO_2$ in culture ratio decreased over 100ppm of $SiO_2$. The highest concenitration of $SiO_2$ (Nagdong-byeo:172.6ppm/lcc, Samgang-byeo:199.8ppm/lcc) in guttation liquid was obtained at 12 hrs after $SiO_2$ applied. Foliar burn seemed to be closely related with $SiO_2$ concentration in guttation liquid.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.271-282
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• 2019

This study was conducted to evaluate physiological activity of Robinia pseudo-acacia leaf and its skin penetration using polymer micelles and skin penetrating peptide. After extraction with Robinia pseudo-acacia using the ethanol and distilled water, various physiological activities were examined. The total concentration of polyphenol compounds was determined to be 47.42 mg/g (ethanol extract), 56.88 mg/g (hydrothermal extract) and DPPH radical scavenging ability at $1,000{\mu}g/mL$ was 44.24% in ethanol extract and it is higher than value(41.50%) in hydrothermal extract. The elastase inhibitory assay showed concentration dependence and elastase inhibition of Robinia pseudo acacia leaf ethanol extract was 54.09%, which was the highest at $500{\mu}g/mL$. In the SOD-like experiments, the concentration-dependent results were showed and the SOD-like activity of the Robinia pseudo-acacia leaf ethanol extract was higher than that of the Robinia pseudo acacia leaf hydrothermal extract at all concentrations. At a concentration of $500{\mu}g/mL$, Robinia pseudo acacia leaf ethanol extract showed the highest SOD-like activity of 76.41%. The tyrosinase inhibition at $20{\mu}g/mL$ was determined to be 56.47% (ethanol extract), 23.05% (hydrothermal extract). In the antimicrobial experiments, the hydrothermal extract had no effect, but ethanol extract represented maximum clear zone of 11.00 mm in Propionbacterium acnes strain and maximum clear zone of 10.50 mm. in Bacillus subtilis strain. To solve the problem of insolubility and to improve skin penetration, PCL-PEG polymer micelles containing Robinia pseudo-acacia leaf ethanol extracts and 1.0% cell permeable peptide, hexa-D-arginine (R6) were successfully prepared with particle size of 108.23 and 126.47 nm and excellent skin permeation effects could be showed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.4
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• pp.343-355
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• 2021

Eelgrass, Zostera marina L., was widely distributed around Sinyangseopji Beach in Bangdu Bay, on the eastern coast of Jeju Island, until breakwater construction in the late 1990s resulted in its complete loss. Six experimental sites were identified for restoration of the Z. marina bed in Bangdu Bay. Using the staple method, 500 Z. marina shoots were transplanted at each site in January 2019 and 2020. The transplants, along with environmental parameters, were monitored for 10 months following transplantation. There were significant differences in underwater irradiance, water temperature, and salinity among the sites, but all were suitable for Z. marina growth. The Ulva species, an opportunistic alga, appeared in spring and accumulated during summer at all sites; however, there was no significant effect of Ulva species on the survival and growth of the eelgrass transplants. Most of the transplanted Z. marina survived, and after 3 months, the density increased by 112.5-300% due to vegetative propagation, with a rapid rate of increase observed during spring and early summer at all sites. For 1-2 months after transplanting, the Z. marina shoots showed signs of transplant shock, after which the shoot density increased at all sites, confirming that all transplants adapted well to the new environment. However, in both 2019 and 2020, during late summer to early fall, the sites experienced heavy damage from typoons (twice in 2019 and three times in 2020) that hit Bangdu Bay. The transplants at two sites located in the center of Bangdu Bay were completely destroyed, but those at three sites located to the west of the bay showed a 192-312% increase in density. Thus, we confirmed that the Bangdu Bay Z. marina bed can be restored, with the highest probability of success for Z. marina restoration on the western side of Bangdu Bay, which is protected from typhoons.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.167-176
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• 2021

When producing recycled asphalt mix, it is important that the old binder of reclaimed asphalt pavement(RAP) should be well melted during blending in the mixer. The recycled asphalt mix is produced by instant mixing(IM) of all materials(RAP, virgin asphalt and new aggregates) all together in the mixer. However, in the same recycled mix, the binder around RAP aggregate was found to show higher oxidation level than the binder coated around the virgin aggregate because the old binder of RAP was not rejuvenated properly while instant mixing. The partially-rejuvenated RAP binder is assumed to be a high stiffness point in IM recycled mix. In this study, the stage mixing(SM) method was introduced; blending RAP and virgin asphalt for the first stage, and then mixing all together with hot new aggregates for the second stage. To compare the effect of the two mixing methods on moisture resistance of recycled mixes, a statistical t-test was performed between SM and IM using indirect tensile strength(ITS) and tensile strength ratio(TSR). Three conditioning methods were used; a 16-h freezing and then 24-h submerging, 48-h submerging, and 72-h submerging in 60℃ water. It was found that the TSR(=ITS_wet/ITS_dry) values of the mixes prepared by SM was clearly higher than the IM mixes, and coefficients of variation of SM mixes were lower than the IM mixes. It was also observed that the ITS_WET of SM was significantly different from the IM at α=0.05 level by statistical t-test. The ITS_WET of SM mix was reduced less than the IM mix in severer conditioned mixes. Therefore, it was concluded that the stage mixing method was an important blending technique for producing better-quality of recycled asphalt mixes, which would show higher moisture resistance than the recycled mixes produced by conventional instant mixing.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.185-194
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• 2006

A fungal strain of Trichoderma having strong chitinolytic activity was isolated from field soil enriched with crabshell for several years. Based on 5.8S rRNA, partial 18S, 28S rRNA genes, ITS1, ITS2 sequence analysis and morphological characteristics, the fungus was identified as Trichoderma asperellum and named as Trichoderma asperellum T-5 (TaT-5). The fungus released lytic enzymes such as chitinase and ${\beta}$-1, 3-glucanse, and produced six antifungal substances in chitin broth medium. To demonstrate the protective effect of TaT-5 against damping-off in cucumber plant caused by Rhizoctonia solani, TaT-5 culture broth (TA), chitin medium (CM) and distilled water (DW) were applied to each pot at 10 days after sowing, respectively. Then, the homogenized hyphae of R. solani were infected to each pot at 1 week after TaT-5 inoculation. During experimental period, fresh weight of shoot and root in cucumber plant more increased at TA treatment compared to other treatments. PR-proteins (${\beta}$-1, 3-glucanase and chitinase) activities in cucumber leaves markedly increased at CM and DW treatments, but the activity slightly increased and then decreased at TA treatment at 3 days after infection of R. solani. The activity of PR-proteins activities in cucumber roots at all treatments decreased with time where the degree of decrement was more alleviated at TA treatment than CM and DW. These results suggest that the lytic enzymes (chitinase and ${\beta}$-1, 3-glucanse) and antifungal substances produced by TaT-5 can reduce the pathogenic attack by R. solani in cucumber plants.

• Journal of Life Science
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• v.22 no.7
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• pp.897-903
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• 2012

Food allergies have become a serious health concern in the past two decades, especially in developed countries. Foods associated with allergies include vegetables, some fruits, shellfish, wheat, egg, chicken, and nuts. To describe the specific fundamentals, etiological factors, and clinical manifestations, we analyzed the different physical frequency on spleen index in sensitized and regular exercise-trained mice. We also conducted a proliferation assay of lymphocytes to OVA, ROS, ASAS, and we determined the cytokine levels. Female BALB/c mice were bred in the animal laboratory of the P and D university under controlled conditions ($22{\pm}2^{\circ}C$, RH 45-55%, and a 12-hour photoperiod). The animals were 6 weeks old at the start of the study and were fed a standard commercial chow diet from 09:00 to 15:00 for the 8-week study period. All animals had access to distilled deionized water ad libitum. They were divided into four groups: a control group (S; control sensitized, n=25), a low-frequency training group (F2, n=25), a mid-frequency training group (F3, n=25), and a high-frequency training group (F5, n=25) following the treatment of exercise time per week. The results were as follows: The mice spleen index showed the highest grade in the F5 group compared with the other groups; this level showed in an exercise frequency-dependent manner. In the proliferation assay of OVA, the F5 group showed the highest grade compared with the other groups; this level was also showed in an exercise frequency-dependent manner. Peritoneal ROS and ASAS showed a statistically significant increase in the F5 group and decreased in the F2 group compared with the S group. However, there were no significant differences in the F3 group. The highest level of IL-4 was found in the F5 group compared with the other groups. However, the highest level of INF-${\gamma}$ was in the F2 group. The results suggest that FDEIA is positively correlated with the frequency of exercise due to the direct effect of physical exercise on peritoneal ROS and the cytokine profile. Further research is needed on the specific mechanism underlying the combined effects of exercise intensity and frequency on physical-induced allergy anaphylaxis.

• Journal of Life Science
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• v.30 no.3
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• pp.260-266
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• 2020

Alcohol impacts many central nervous systems, such as dopamine, serotonin, opioids, and gamma-aminobutyric acid (GABA), leading to addiction. Many studies have investigated the relationship between GABA and alcoholism. The purpose of this study was to investigate the effects of GABA high and low rice intake on the alcohol intake behavior of mice. Black sticky rice with giant embryo (BSRGE), black sticky rice (BSR), giant embryo rice (GER), and rice (Rice) were germinated for 48 hr in brown rice. The embryos were then collected and used in the study. The diets were fed to respective C57BL/6 mouse groups ad libitum for 16 days and investigated for 2 hr alcohol intake, 22 hr water intake, 24 hr feed intake, and body weight. As a result of the repeated measure of ANOVA for the daily change of alcohol intake for 2 hr daily between the BSRGE and BSR groups, there was a significant difference in the number of days of intake (DF = 7, F = 4.812, p = 0.026). A significant daily decrease in alcohol intake was observed in the BSRGE group compared to the BSR group. This reduction was consistent from Day 10 to Day 16. Alcohol consumption also significantly decreased in the GER group compared to the Rice group. This decrease was observed from Day 12 to Day 16. In conclusion, BSRGE and GER resulted in decreased alcohol intake in C57BL/6 mice compared to BSR and rice. This suggests that BSRGE may prevent relapse in patients with alcohol use disorder.

• Korean Journal of Poultry Science
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• v.36 no.1
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• pp.57-67
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• 2009

These studies were conducted to investigate the various dietary CP and ME feeding effect on productivity, blood composition and meat quality in cross bred chicks. Seven hundred twenty one day old cross bred chicks (Hanhyup Samho) were alloted to the floor pen for early starting (0~2 weeks), starting (3~5 weeks), growing (6~8 weeks), finishing period (9~10 weeks). Dietary ME and CP were 3,000, 3,100 kcal/kg, and 22% for early starting period, 19, 20, 21% for starting period, 18, 19, 20% for growing period, 17, 18, 19% for finishing period. Weight gain and feed consumption were weekly measured and feed conversion ratios were calculated. Blood and breast meat were collected at the end of experiment. Birds fed ME 3,100 kcal/kg diets improved significantly compared with others for the first two weeks (P<0.05). Feed conversion was statistically improved in CP (22)21% treatment relative to that of CP (22)20% from three to five weeks of age. No difference were found from 6 to 8 weeks of age. Weight gain and feed conversion also improved in ME 3,100 kcal/kg treatments, but feed intake decreased significantly in CP ($22{\times}21{\times}20$)19% treatment for the rest of experimental period (P<0.05). There was interaction between ME and CP for the first five weeks (P<0.05). Blood total protein showed higher in ME 3,100 kcal/kcal treatment than ME 3,000 kcal/kg (P<0.05). There were no differences in albumin, total cholesterol and glucose, but CP ($22{\times}20{\times}19$)18 treatment showed higher glucose than other treatments (P<0.05). Cooking loss, tenderness and water holding capacity were not different. However, pH was dependent on dietary ME, CP and existing the interaction between ME and CP treatments (P<0.05). As the results of this experiment, ME and CP were confirmed the 3,000 kcal/kg, 22% for the first two weeks 3,100 kcal/kg, 21% from three to five weeks of age, 3,100 kcal/kg, 18% for the growing period, 3,100 kcal/kg, 17% for the rest of period. However, further research would be required to confirm more optimum dietary nutrition for cross bred chicks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.624-629
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• 2014

Obesity is the leading metabolic disease in industrialized countries and is closely associated with coronary heart disease, hypertension, diabetes, and cancer. The objective of this study was to evaluate the anti-adipogenic effects of two roasted coffee beans, Vietnam robusta (VR) and Ethiopia Mocha Sidamo G2 (ES), as well as fermented coffee beans with Monascus ruber (MR) mycelium on differentiation of 3T3-L1 preadipocytes. Treatments with 1,000 ${\mu}g/mL$ of hot water extract from coffee beans significantly reduced intracellular lipid accumulation. In addition, VR more effectively inhibited transcription factors such as $PPAR{\gamma}$, $C/EBP{\alpha}$, FAS, and aP2 compared to ES. Further, ES fermented with MR showed more effective anti-adipogenic activity than non-fermented ES. These results suggest that VR and ES inhibit adipocyte differentiation which may contribute to their anti-adipogenic properties.