• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.493-500
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• 1998

To investigate the effects of light intensity on the growth, and the critical minimum light intensity for growing of Cornus controversa seedlings at the stage of cotyledon, hypocotyl elongation, cotyledon expansion, the times of leaves appearance, dry weights of each organ, and specific leaf area(SLA) were measured on a growth chamber with several light intensity gradients(385, 32, 17, 8, and $5{\mu}mol\;m^{-2}s^{-1}$). There was a positive correlationship between the size of cotyledon and the biomass of cotyledon and total seedling. Hypocotyl was more elongated under relatively low light intensities, such as 32, 17, 8, and $5{\mu}mol\;m^{-2}s^{-1}$ than under $385{\mu}mol\;m^{-2}s^{-1}$ light intensity, however, dry weight of the hypocotyl was adverse. As the light intensities decreased, the leaf appearance was delayed and the number of leaves decresed. In addition, leaves did not appear under $8{\mu}mol\;m^{-2}s^{-1}$ and $5{\mu}mol\;m^{-2}s^{-1}$ light intensity. Although cotyledons were more fully expanded under 32 and $17{\mu}mol\;m^{-2}s^{-1}$ light intensities than $385{\mu}mol\;m^{-2}s^{-1}$ light intensity, the dry weights of cotyledons were greater under the high light intensity. The dry weight of cotyledon, hypocotyl, root and leaves showed a decreased pattern with decreasing light intensities, but root to shoot(hypocotyl+leaves) ratio rapidly increased. Roots did not develop below $8{\mu}mol\;m^{-2}s^{-1}$ light intensity. In conclusion, the results showed that the critical minimum light intensity for growing of Cornus controversa seedlings was above $17{\mu}mol\;m^{-2}s^{-1}$ light intensity.

• Research in Plant Disease
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• v.23 no.2
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• pp.150-158
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• 2017

Pear scab caused by Venturia nashicola has been reported as an important disease of pear resulting in lowering the quality of pear fruits. In this study, it was conducted to investigate the relationship between resistance of V. nashicola and mutation of ${\beta}$-tubulin gene and the fungicide resistance in field isolate group in benzimidazole fungicides. Responce of V. nashicola to carbendazim could be classified into 3 groups as sensitive that does not grow at all on PDA amended with $0.16{\mu}g/ml$ of carbendazim, low resistance that could not grow in $4.0{\mu}g/ml$ medium, and high resistance that can grow even at $100{\mu}g/ml$. Thirty isolates of V. nashicola collected from 3 regions as Wonju, Naju, and Okcheon were highly resistant to carbendazim. Analysis of the nucleotide sequence of ${\beta}$-tubulin gene of V. nashicola showed that there was no difference in the nucleotide sequence between the sensitive and the low-resistant isolate, but GAG at codon 198 (glutamic acid) was replaced with GCG (alanine) in the high-resistant isolate. Among 10 isolates obtained from the Okcheon, 5 isolates showed the substitution of glycine for glutamic acid, which were resistant to carbendazim, but more sensitive to the mixture of carbendazim and diethofencarb than others. Through these results, all isolates of V. nashicola isolated in pear orchard were found to be resistant to benzimidazoles. Also, mutants E198A and E198G at ${\beta}$-tubulin were found to be important mechanisms of V. nashicola resistance against benzimidazole fungicides.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.96-115
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• 2017

Understanding effects of thermal pollution and acidification has long been a concern of aquatic ecologists, but it remains largely unknown in Korea. This study was performed to elucidate the effects of thermal wastewater effluent (TWE) and acid rain on water quality and attached algae in a small mountain stream, the Buso Stream, a tributary located in the Hantan River basin. A total of five study sites were selected in the upstream area including the inflowing point of hot-spring wastewater (HSW), one upstream site (BSU), and three sites below thermal effluent merged into the stream (1 m, 10 m and 300 m for BSD1, BSD2, and BSD3, respectively). Field surveys and laboratory analyses were carried out every month from December 2015 to September 2016. Water temperature ranged $1.7{\sim}28.8^{\circ}C$ with a mean of $15.0^{\circ}C$ among all sites. Due to the effect of thermal effluent, water temperature at HSW site was sustained at high level during the study period from $17.5^{\circ}C$ (January) to $28.8^{\circ}C$ (September) with a mean of $24.2{\pm}3.7^{\circ}C$, which was significantly higher than other sites. Thermal wastewater effluent also brought in high concentration of nutrients(N, P). The effect of TWE was particularly apparent during dry season and low temperature period (December~March). Temperature effect of TWE did not last toward downstream, while nutrient effect seemed to maintain in longer distance. pH ranged 5.1~8.4 with a mean of 6.9 among all sites during the study period. The pH decrease was attributed to seasonal acid rain and snow fall, and their effects was identified by acidophilic diatoms dominated mainly by Eunotia pectinalis and Tabellaria flocculosa during March and August. These findings indicated that water quality and periphyton assemblages in the upstream region of Buso Stream were affected by thermal pollution, eutrophication, and acidification, and their confounding effects were seasonally variable.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.469-480
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• 2003

Laboratory leaching experiment study carried out to estimate a extent of heavy metals that could be leached out when acid rain(pH 5.0-3.0) and strong acidic solution(pH 2.5-1.0) reacted with tailings and contaminated soils from abandoned metal mines. In slightly to moderately acid conditions(pH 5.0-3.0), As, Pb and Zn dissolutions became significantly increased with decreased pH in tailing, while dissolution of these elements was very limited in contaminated soil. These results suggested that moderately acid rainwater leaches Pb, As and Zn from the tailings, while these elements would remain fixed in contaminated soil. In the pH range of 2.5-1.0(strongly acid condition), Zn, Cd and Cu concentrations of leachate rapidly increased with decreased pH in contaminated soil, while Pb, As and Co dissolutions became importantly increased in tailings. The experimental solubility of Zn. Cd and Cu was very low even at very low pH values(up to pH 1), except for CY4(Cheongyang mine). These can result from an incomplete dissolution or the presence of less soluble mineral phases. So, the solubility of heavy metals depends not only on the pH values of leachate but also on the speciation of metals associated with contaminated soils and tailings. The relative mobility of each element within failings at the pH 5.0-3.0 of the reaction solution was in the order of Pb>Zn>Cd>Co=Cu>As. In case of pH 2.5-1.0 of the reaction solution, the relative mobility of each element within contaminated soils and tailings were in the order of Zn＞Cd>Cu>Co>Pb=As for contaminated soils, and Pb>Zn>Cd>hs>Co>Cu for tailings. The obtained results could be useful for assessing the environmental effects and setting up the restoration plan in the areas.

• Journal of Hospice and Palliative Care
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• v.5 no.1
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• pp.24-30
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• 2002

Background : Pain is one of the most feared consequences of cancer. $65{\sim}85%$ of cancer patients experienced severe pain, and sometimes high dose morphine is used to these patients. But many doctors still have 'opioid-phobia' and hesitate to use high dose morphine. We investigated the morphine therapy in terminal cancer patients during the last 1 week to death, and found any differences according to the morphine dosage. Methods : 93 patients admitted to National Health Insurance Corporation Ilsan Hospital, department of family medicine for hospice care between September 2000 and the end of October 2001 and lived more than 1 week entered in the study. We investigated the demographic data, laboratory tests and sufficient dosage of morphine for pain control. According to the calculated dosage by OME(oral morphine equivalent), patients were divided into low dosage group (${\leq}150mg/day$) and high dosage group (>150 mg/day). The chi-squared test were used to evaluate the influence of age, gender, tumor sites, metastasis and adverse effects of morphine. Results : Mean age was $65.0{\pm}13.1year$ in low dosage group and $59.9{\pm}11.6year$ in high dosage group. 32 men (50.0%) and 32 women (50.0%) were included in low dosage group and 15 men (51.7%) and 14 women (48.3%) in high dosage group. Stomach was the most frequent tumor site and lung was the next. Metastasis were found 58 (90.6%) in low dosage group and 28 (96.6%) in high dosage group. In other palliative radiotherapy and adverse effects, there were no differences in both group. Conclusion : During the last 1 week to death in cancer patients, there were no difference according to the morphine dosage. So we don't have to have 'opioid-phobia' in treating the terminal cancer patients.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.258-263
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• 2016

The risks of sanitary indicative bacteria, heavy metals and chlorinated derivatives in 94 cases of sanitary wet towels used in food services (39 from sanitary wet towel treatment business, 55 from food services) were assessed in the present study. Lead was detected in the range of N.D.~0.41 mg/kg (75 cases were not detected), N.D.~0.25 mg/kg of arsenic (93 cases were not detected), N.D.~0.01 mg/kg of cadmium (7 cases were lower than limit of quantitation; 87 cases were not detected), 0.003 mg/kg ~ 0.09 mg/kg of mercury. And chromium (VI) was not detected from all samples. The level of lead was the highest among the tested heavy metals, and the highest concentration of lead was 0.41 mg/kg. However, it was only 2.1% of legal limit (less than 20 mg/kg). The average moisture content of the samples was 61.9% (50.0% ~ 77.0%) and it showed no relevance to the detection of bacterial counts. Escherichia coli was not detected. Bacterial counts were detected 43 cases and among them, 24 cases were exceeded the legal limit. It was verified that the packaging conditions of sanitary wet towel (whether it is packed by a piece or not and sealed or not) are critical factors to cause the germ contamination and cross contamination in the wet towels. The chlorinated derivatives (chlorites and chlorates) were detected in 17 (19.3%) out of 88 cases. The results would be used as preliminary information to establish the programs of "Safety education for manufacturers and public policy of safety".

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.227-234
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• 2006

For the biological control of the greenhouse whitefly, aphids, American leaf-miners, Encarsia formosa, Aphidius coiemani, Diglyphus isaea, and Dacnusa sibirica were used as biological control factors. Otherwise, many kinds of environment friendly agricultural materials were also used in the kindly environment friendly farming. For testing the toxicity of environment friendly agricultural materials against to insect parasitoids as biological control factors, 61 environment friendly agricultural materials were selected by using methods and periods with insect parasitoids in the greenhouses. Environment friendly agricultural materials were sprayed to mummies and adults of E. formosa and A. colemani, and adults of Diglyphus isaea and Dacnusa sibirica in laboratory condition. Emergence rates were checked during 12 days after spray to mummies of E. formosa and A. colemani, and survival rates were at 24 and 48 hours after viral test for adult parasitoids, with 10% sugar solution. Emergence rates of E. formosa mummies were inhibited by sprayed the fungicidal environment friendly agricultural material (FEFAM) E and the environment friendly agricultural materials contained molybdenum (EFAMMo) G as 0.4 and 2.7%, respectively. E. formosa adults were not survived in vial for 48hours after sprayed and dried with the environment friendly agricultural materials contained plant extract (EFAMPE) J and the EFAMMo C. The environment friendly agricultural materials contained microelements (EFAMMEs) B and EFAMPE H, environment friendly agricultural materials contained useful soil microorganisms (EFAMSMs) H, FEFAM A and FEFAM D were recorded low survival rates of E. formosa adults with 6.7, 13.3, 13.3, 20.0 and 20.0, respectively. In case of the spraying environment friendly agricultural materials to mummies of A. colemani there were low emergence rate from mummies to adults as around 20s % with water spraying as control. A. colemani adults were not survived in vial with EFAMMo C. EFAMPE J, EFAMPE F, EFAMPE H, EFAMSM H were recorded low survival rates under 20% as 6.7, 13.3, 13.3 and 13.3, respectively, D. isaea and D. sibirica adults were not survived in vial with EFAMPE J. EFAMMo C was 53.3% of survival rates in 48 hours vial tests. D. isaea and D. sibirica were not affected by environment friendly agricultural materials compared with E. formosa and A. colemani.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.106-110
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• 2009

In order to reduce the bitter taste and improve the bioavailability of red ginseng extract(RGE), inclusion complexes (RGE-CD) of the extract with ${\alpha}-,\;{\beta}-,\;{\gamma}$-cyclodextrin were prepared and studied for their sensory quality and bioavailability compared to RGE. By complexation, the bitter taste-reducing efficacies of ${\alpha}$-CD and ${\beta}$-CD were much lower than that of ${\gamma}$-CD. In comparative sensory analysis for the bitter taste, RGE-${\gamma}$-CD10, prepared using 10%(w/w) of ${\gamma}$-CD, showed a score of 1.93(decreased by about 78%) compared to RGE as the control. In addition, in sensory analysis for flavor, RGE-${\gamma}$-CD10showed a score of 5.60. Upon increasing the amount of ${\gamma}$-CD to 15%(w/w) and 20%(w/w), respectively, the bitter taste of RGE-${\gamma}$-CD was removed and the flavor of RGE disappeared(scores of 2.67 and 1.67, respectively). Therefore RGE-${\gamma}$-CD10 was chosen as an optimum. The same dosages of RGE and RGE-${\gamma}$-CD10 were orally administered to SD(Sprague-Dawley) rats on a saponin basis, and the plasma concentrations of ginsenoside Rg1 and Rb1 were measured over time to estimate the average AUC(area under the plasma concentration versus time curve) of the ginsenosides. After the oral administration, there were no significant differences in the AUC values of the RGE and RGE-${\gamma}$-CD 10 groups for ginsenoside Rg1. However, AUC values for ginsenoside Rb1 were $25.8{\mu}g{\cdot}hr/mL$ in the RGE group and $81.5{\mu}g{\cdot}hr/mL$ in the RGE-${\gamma}$-CD 10 group, respectively. Therefore, the bioavailability of ginsenoside Rb1 in the RGE-${\gamma}$-CD 10 group was significantly higher by up to 315% compared with that in the RGE group(p = 0.0029). These results show that the bitter taste of RGE can be simultaneously removed by the complexation of RGE and ${\gamma}$-CD(RGE-${\gamma}$-CD) along with increased bioavailability.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.5
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• pp.82-93
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• 2008

This research focused on the process in which 'the same scenery' is recognized and represented as 'a different landscape' to determine the symbols and meaning of the scenery and landscape included in real-scenery landscape paintings of the 18th-19th centuries. As a result of analyzing the visual points, the content and expressions of 25 real-scenery landscape paintings of Chong Seok Jeong(叢石亭), it can be seen that the transmission of a kind of semiotic landscape on the basis of a specific symbol was accomplished naturally through imitation and representation for the purpose of the expression of Chong Seok Jeong-like idealized scenery. This shows that the unique images of Chong Seok Jeong have long been passed down after taking root as a unique benchmark The meaningful symbol of 'a strange Saseonbong(四仙峰)', which is broken by the spray after rising high, and 'a pine forest' have both been transmitted as being in the manner of Chong Seok Jeong. This has been equipped with the stereo-type scene by being a collective symbolization as the psycho-scenes in memory element of Chong Seok Jeong. Through the pictures of both Gyeomjae(謙齋) and Danweon(檀園), the process by which a specific painter's pictures become acculturated is highly interesting. The scenery expressed in these pictures was clearly that of a landscape of which its particularly emotions and remembrances were repainted through the experience of several places and original sketches. This can be explained as the concept in which the image from 'a specific scenery' gained through actual experience, that is, a personal feeling, has been expressed. The picture that was expressed as a different figure even at the same visual point for the same scenery is the result that was redefined through the scenery subject's recognition. Also, the modification of the scenery object can be colorful through meditation and Sachu(邪推: guessing with wicked doubt). The scenery recognized newly through adoption, omission and emphasis, it is 'the specific scenery' in the heart and is a figure having been more similar to 'a landscape' if the objective life reproduction before being acculturated is a figure similar to the scenery. So, the concept looks like being very persuasive that 'the nature with objectivity captured sensuously' simply is the scenery, and that 'the subjective phenomenon having acquired the cultural nature by being introspected in the method of aesthetic nostalgia is a landscape'.

• Economic and Environmental Geology
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• v.37 no.3
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• pp.303-309
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• 2004

Pyrochlores were known as promising materials for the immobilization of radioactive actinide. Accordingly, we synthesized pyrochlores with Gd$_2$Ti$_2$$O_7$ and Gd$_2$Zr$_2$$O_7$compositions by sintering method, and studied its properties and phase relations in Gd-Ti-O and Gd-Zr-O system. The mixed powders were pressed into pellets under 200-400 kgf/cm$^2$ at room temperature. and then sintered at 1000-1$600^{\circ}C$ for 0.5-40 hours. The synthesized samples were analyzed and were identified with XRD and SEM/EDS analyses. The optimal synthetic conditions of pyrochlores with Gd$_2$Ti$_2$$O_7$composition were at 140$0^{\circ}C$/0.5hrs, 130$0^{\circ}C$/3hrs and 120$0^{\circ}C$/20hrs. Its chemical composition was $Gd_{2.0-2.1}$$Ti_{1.9-2.0}$$O_7$ and similar to the stoichiometric composition without any relationship in temperature and atmosphere. The optimal synthetic conditions of pyrochlores with $Gd_{2}$$Zr_{2}$$O_7$composition were at 155$0^{\circ}C$/40hrs and 1$600^{\circ}C$/30hrs. The compositions of pyrochlore synthesized from these optimal conditions were irregular with $Gd_{1.5-2.4}$$Zr_{1.7-2.4}$$O_7$. Such heterogeneity indicates that the reaction rate of pyrochlore with Gd$_2$Zr$_2$$O_7$composition is very low, and then its equilibrium state could not be attained even for 40 hours which was the longest sintering time in this research.