• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.154-161
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• 2008

Phellinus linteus (PL) has been known to exhibit potent biological activity. The present study was designed to investigate lipase-inhibitory and anti-oxidative activity of the methanol extract and the powder of PL fruiting body. The methanol extract of PL appeared to have the inhibitory activity against pancreatic lipase with an $IC_{50}$ value of $36.3\;{\mu}g/mL$, and the scavenging activity of DPPH radical with an $IC_{50}$ value of $20.1\;{\mu}g/mL$, which was similar to that of vitamin C ($IC_{50}\;18.3\;{\mu}g/mL$). To investigate the lipase-inhibitory and anti-oxidative effect of PL on animal, Sprague-Dawley rats were fed with high-fat diet supplemented with either 2% or 5% PL powder for 8 weeks. Total food intake was significantly increased, but body weight was not changed by PL powder supplementation. However, fecal fat excretion of the experimental groups fed with the PL powder were higher than that of the control group. PL powder showed a decrease in the plasma total cholesterol, LDL-cholesterol, and the hepatic total cholesterol levels. The anti-oxidative enzyme activities were also affected by PL supplementation. Glutathione peroxidase (GSH-Px) in the plasma and liver were significantly increased by 98% and 46% in the 2% PL group, and 99% and 32% in the 5% PL group, respectively. Total superoxide dismutase (T-SOD) activity was not affected by PL supplementation. DNA damage was measured by the comet assay in the lymphocytes collected after 2 weeks, 4 weeks, and 8 weeks of feeding PL supplemented diet. Lymphocyte DNA damage was decreased in the PL supplemented group. Furthermore, PL feeding enhanced the resistance to lymphocyte DNA damage caused by an oxidant challenge with $H_2O_2$.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.53-61
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• 1986

The races of soybean cyst nematode, Heterodera glycines were investigated at 13 localities in Kyungpook, Chungpook and Cheonnam provinces for the resistant soybean variety selection to soybean cyst nematode. Race C, 1, and 5 were distributed and among them race 5 was dominant in Korea. Native soybean 203 lines and 25 introduced soybean varieties were investigated in field where soybean cyst nematode race 5 infested. As the result, the reproduction of soybean cyst nematode in native soybean lines decreased on entry number 18, 21, 36, 38, 41, 42, 43, 45, 55, 59, 68, 72, 75, 93, 94, 95, 98, 123, 131, 136, 146, 170, 174, 187, 190, 191 than others. And then, in pot experiment, entry number 170 showed moderately resistant with 10 cysts per root, while entry number 55 was decreased reproduction a little and the other 25 line appeared susceptibility. In introduced soybean varieties, Peking, Illsoy and PI90763 showed resistance and not reproduction in field and pot experiment. But Custer, Delmar, Dyer and Jackson represented moderately resistant under 10 cysts, while the other 18 varieties were susceptible. In yield analysis, native soybean line 170 showed the same tendency as Peking and PI90763 known for resistant varieties in decreased rate of branch number, pod number, pod weight per plant and weight of 100 grains. Peking and PI90763 decreased at the rate of under 1.6% in branch number, pod number, pod weight per plant and weight of 100 grains, while Illsoy showed a little higher decreased rate of 3.8% in pod number and 3.4% in pod weight per plant. Custer, Delmar, Dyer and Jackson represented a little higher decreased rate in yield.

• Clean Technology
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• v.21 no.1
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• pp.76-82
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• 2015

Volatile organic compounds (VOC) free adhesives have been interested by many scientists and engineers due to environmental regulations and the safety of industrial workers. In this work, a series of composites composed with bisphenol A epoxy resin used as solvent, dicyandiamide, and promoter were prepared to investigate the most appropriate molar ratio for steel-steel adhesion. The cured test specimen of each composite were measured with universal testing machine (UTM) to figure out mechanical properties such as tensile strength, Young’s modulus, and elongation. Furthermore, the lap shear strength of the specimen was tested with UTM while impact resistance was measured with Izod impact tester. The composite whose molar ratio of epoxy resin to curing agent is 1 : 0.9 (sample 3), showed better tensile strength, coefficient of elastic modulus, elongation, and impact strength than other composites did. The highest tanδ from dynamic mechanical analysis (DMA) was observed from sample 2 (epoxy resin: dicy = 1 : 0.7) while sample 3 showed slightly lower tanδ than that of 2. The morphology of the fracture surface of the cured composites from SEM showed that the number of subtle lines on the surface caused by impact increase as the contents of amine curing agent accrete. Furthermore, the viscosity change of sample 5 (epoxy resin: dicy = 1 : 1.3) was observed to confirm its storage stability.

• Journal of Ginseng Research
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• v.36 no.4
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• pp.461-468
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• 2012

In this study, photosynthetic parameters such as the net photosynthesis rate, stomatal conductance, intercellular $CO_2$ concentration, and transpiration rate were examined in selected ginseng varieties and/or lines that are resistant (Yunpoong, HTIR 1, HTIR 2, and HTIR 3) and susceptible (Chunpoong) to high temperature injury (HTI). The net photosynthesis rate increased with the increase in the light intensity in all the HTI-resistant and -susceptible ginseng lines with a light saturation point of $200\;{\mu}mol\;m^{-2}s^{-1}$, except for Yunpoong that had a light saturation point of $400\;{\mu}mol\;m^{-2}s^{-1}$. At the light saturation point, the net photosynthesis rate in July was highest in HTIR 3, at $4.2\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and was lowest in Yunpoong, HTIR 1, Chunpoong, and HTIR 2, in that order, at 1.9 to $3.7\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The net photosynthesis rate in August was highest in Yunpoong at $5.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and lowest in HTIR 1 and HTIR 3 ($4.5\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$) and in other lines, in that order, at 2.8 to $2.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The stomatal conductance in July was highest in HTIR 3 (0.055 mol $H_2O\;m^{-2}s^{-1}$) and Yunpoong, Chunpoong, HTIR 1, and HTIR 2 were 0.038, 0.037, 0.031, and 0.017 in that orders. In August, meanwhile, HTIR 1 showed the highest as 0.075, and followed by HTIR 3, Chungpoong, and HTIR 2 with 0.070, 0.047, and 0.023, respectively. The intercellular $CO_2$ concentration at the light saturation point in July and August was much lower in HTIR 2 at 139 and $185\;{\mu}mol\;mol^{-1}$ than in the other ginseng lines at 217 to 257 and 274 to $287\;{\mu}mol\;mol^{-1}$, respectively. The transpiration rate in July and August was higher in the HTI-resistant lines of Yunpoong, HTIR 1, and/or HTIR 3 at 0.83 to 1.03 and 1.67 to 2.10 mol $H_2O\;m^{-2}s^{-1}$ than in the other ginseng lines at 0.27 to 0.79 mol $H_2O\;m^{-2}s^{-1}$ and 0.51-1.65 mol $H_2O\;m^{-2}s^{-1}$, respectively. Conclusively, all the photosynthetic parameters that were examined in this study were generally higher in the HTI-resistant ginseng lines than in the HTI-susceptible lines, except for HTIR 2, and were much higher in August than in July, especially in the resistant ginseng lines. All these results can be used to provide basic information for the selection of HTI-resistant ginseng lines and the application of cultural practices that are efficient for ginseng growth, based on the photosynthetic characteristics of the lines.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.601-613
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• 2011

The purpose of this study is to provide an protected wildlife species and potential habitats in Seoul through the overall present status of the species which live in Seoul. This study was performed in Seoul, the entire area of which is 605.52 $km^2$. We analyzed a total of 57 studies, including academic papers and research reports, for the natural ecology in Seoul. As for the results from the study, it was found that a total 1,907 species from 5 taxa were inhabiting and growing within the area. Among the total, plants of 1,656 species accounted for 86.7%, 197 species of wild birds made up 10.3%, 29 species of amphibians and reptiles consisted of 1.5%, and 27 species of mammalia totaled 1.4%. A total of 440 species except foreign species and species legally preserved by the Ministry of Environment, common species and uncertain species were selected as primary candidates. By taxon, it shows 212 species of plants, 180 species of wild birds, 24 species of mammalia, and 24 species of amphibians and reptiles. For extensive research subjects and research data limited in certain insect family, analysis by literature for discovered insects was excluded. The selection criteria for the second candidate species was based on extinction crisis, rarity, historicity and locality, academic value, habitat specificity, etc. The second candidate species from the primary species were selected through taxon experts' evaluations. As for the results of the selection of the second candidates, a total 77 species were selected through the experts' evaluations. Each species by taxon was 25 species for plants, 21 species for wild birds, 5 for mammalia, 10 for amphibians and reptiles and 16 species for insects. A site investigation for the second candidates was conducted to select the final candidate species. For the target areas, the habitats of the second candidates given by the literature and 46 potential areas in Seoul, which show good natural resistance, were finally selected. From the result of the site investigation, it was found that 14 species of plants, 19 species of wild birds, 2 species of mammalia, 4 species of amphibians and reptiles, and 16 species of insects were actually inhabiting Seoul; thus, the final 55 protected species were selected.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.1-7
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• 2010

This study was carried out to investigate plow pan characteristics and to grasp the relationship between its particle size distribution fractal dimension ($D_m$) and water transport in paddy plow pan. Twenty four soil sampling sites with different management groups, ordinary and sandy-textured, were selected and investigated for physical properties of soils such as Yamanaka hardness in April, non-submerged condition, before rice seedling transplanting. The plow pan appearing depth and thickness was determined by penetration resistance profile. Undisturbed core samples with five replicates were sampled at plow pan layerwith 2 inch cores for measuring soil bulk density and saturated hydraulic conductivity. The particle size distribution fractal dimension ($D_m$) was calculated by the method following the procedure Tylerand Wheacraft (1992), using the USDA-based particle size analysis datawith fractions of 0-0.002, 0.002-0.053, 0.053-0.1, 0.1-0.25, 0.25-0.5, 0.5-1.0, and 1.0-2.0 mm. The plow pan of investigated fields appeared at a range from 5 to 30 cm depth, showing minimum value in sandy-textured management group and maximum value in ordinary management group. The thickness of plow pan were distributed from 5 to 17 cm, showing both minimum and maximum values in sandy-textured management group. Averagely, the plow appearing depth were deeper in ordinary management group than in sandy-textured management group, whereas the reverse in the thickness of plow pan. The particle size distribution fractal dimension ($D_m$) had higher value with finer textures, with higher fractality in coarser texture. Saturated hydraulic conductivities, $K_s$, of plow pan soils distributed from 0.5 to 1420 mm $day^{-1}$, having the highest value in sandy skeletal soils. The $K_s$ decreased with decreasing clay content and $D_m$, showing power function relationships. The coefficient of determination, $R^2$, of the fitted power functions were higher in $D_m$ as x-axis than in clay content. This means that $D_m$ could give us more effective estimation than clay content. Especially, sandy-textured paddy soils had higher $R^2$, compared to ordinary paddy soils. $K_s$ of relatively coarse-textured soils with less than 18%of clay content, therefore, was more dependent on particle size distribution than that of relatively fine-textured soils. From these results, it could be concluded that the fractal scaling gives us a unique quantity describing particle size distribution and then can be applied to estimate saturated hydraulic conductivity, especially more effective in coarse-textured soils.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.1039-1046
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• 1998

Background: Sleep-related breathing disorders(SRBD) and periodic leg movements disorder(PLMD) are both common, and are considered as separate sleep disorders. However, both disorders show high comorbidity. SRBD and PLMD can result in excessive daytime sleepiness and insomnia due to frequent sleep fragmentation. So, it is very important to consider the presence of PLMD, when we are dealing with the diagnosis and management of SRBD. The objectives of this study were to determine the incidence of PLMD in patients with SRBD, and to describe any differences between patients with and without PLMD. Method: The authors reviewed the sleep recordings of 106 patients with a final diagnosis of SRBD(obstructive sleep apnea or upper airway resistance syndrome), who underwent full nocturnal polysomnography, including the monitoring of the anterior tibialis electromyogram. All sleep records were recorded and scored using the standard criteria. The data was analyzed by the student t-test. Result: 106 patients(M=76, F=30) were included in the analysis. Data revealed a mean age of $49.5{\pm}13.6$ years, a respiratory disturbance index(RDI) of $22.3{\pm}25.4$/hour sleep, a lowest oxygen saturation of $84.9{\pm}11.3%$, a maximal esophageal pressure of $-41.0{\pm}19.1cmH_2O$, and PLM index(PLMI) of $13.1{\pm}22.4$movements/hour sleep. Forty four percent(47 of 106 patients) had a PLMI of greater than 5 on this study. The mean age of the patients with PLMD was significantly higher than that of the patients without PLMD(p<0.005). Female patients with SRBD accompanied more PLMD(p<0.05). The apnea index of the patients with PLMD was significantly lower than that of the patients without PLMD(p<0.01). The percentage of stage 1 sleep in the patients with PLMD was significantly lower than that of the patients without PLMD(p<0.05). Conclusion: The prevalence of PLMD in the patients with SRBD was high at 44.3%. The patients with PLMD were older and had more high RDI in comparison to the patients without PLMD, which was consistent with previous findings. The authors recommend that more careful consideration of PLMD is required when diagnosing and treating SRBD.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Journal of Life Science
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• v.22 no.9
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• pp.1224-1230
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• 2012

Cancer chemotherapy drugs command a large share of the market, and the development of new therapeutics with high efficacy and specificity is an active area of study. Recently, the development of cancer therapeutics from natural products targeting angiogenesis has drawn attention due to conventional chemotherapeutics showing serious side effects and resistance in cancer cells. In this study, we investigated the pharmacological efficacy of Gomisin A, an active ingredient of Schizandra chinensis baillon, on tumor growth and metastasis. Administration of Gomisin A at 10 and 100 ${\mu}g/ml$ reduced tumor growth in vivo by $80.5{\pm}8.1%$ and $96.2{\pm}2%$, respectively, compared with positive tumor controls. Treatment of Gomisin A in normal and various tumor cell lines did not exert significant toxicity. Mice treated with Gomisin A at a concentration of 10 and 100 ${\mu}g$/head showed a significant reduction in tumor-induced angiogenesis of $151{\pm}16.9%$ and $98.5{\pm}29.5%$, respectively. Furthermore, tumor metastasis analysis revealed that the administration of Gomisin A at a concentration of 10 and 100 ${\mu}g$/head inhibited tumor metastasis by $13.5{\pm}8.56%$ and $58.3{\pm}9.12%$, respectively. In addition, Gomisin A significantly decreased cell adhesion of the B16BL6 cells to the extracellular matrix. These results demonstrate that Gomisin A inhibits tumor growth via suppression of angiogenesis and tumor metastasis inhibition, without cellular toxicity. The pharmacological efficacy of Gomisin A suggests that it may be a potential candidate for the development of cancer drugs.

• Korean Journal of Microbiology
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• v.53 no.1
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• pp.20-28
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• 2017

Physical sterilization methods using ultraviolet radiation and ionizing radiation such as gamma ray and electron beam are applied in various industry fields due to disinfection effects and economic efficiency but may also cause microbial mutation. In this research, Salmonella enterica and Escherichia coli strains were treated with ionizing and ultraviolet radiation and their survival rate, mutation rate, and DNA damage were studied to evaluate the genetic safety. The survival rate of the strains decreased drastically as the irradiation dose of ultraviolet ray, gamma ray, and electron beam increased, and over 90% of the strain was exterminated at a dosage of $0.40{\sim}25.06mJ/cm^3$, 0.11~0.22 kGy, 0.14~0.53 kGy respectively. In SOS / umu-test, genotoxicity causing DNA damage was identified in all samples. In Ames test, back-mutation rate increased to $3.82{\times}10^{-4}$ and $9.84{\times}10^{-6}$ respectively when exposed to ultraviolet ray and gamma ray. At exposure to ultraviolet ray, gamma ray, and electron beam with dosage of over 99.99% extinction rate of S. enterica TA100, back-mutation rate increased 347 times, 220 times, 0.6 times respectively to the spontaneous back-mutation rate. Rifampicin resistance mutation rate of E. coli CSH100 exposed to ultraviolet ray, gamma ray, and electron beam was $2.46{\times}10^{-6}$, $1.66{\times}10^{-6}$, $4.12{\times}10^{-7}$ respectively. Therefore, gamma radiation is effective in microorganism control from the perspective of disinfection and electron beam has the advantage of sterilizing with little DNA damage and bacterial mutation.