• Journal of Wetlands Research
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• v.15 no.4
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• pp.535-541
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• 2013

The urbanization affects significantly on a natural water circulation system by increasing the imperviousness rate. It is also negatively affecting on urban temperature, environmental pollution, water quality, and aqua-ecosystems. The Korea MOE (Ministry of Environment) adapted a new environmental policy in order to reduce the impact of urbanization, which is the Green Stormwater Infrastructure (GSI) program. The GSI can be achieved by protecting conservable green spaces, enlarging more green spaces, and constructing more permeable pavements. The GSI is including many different techniques such as bioretention, rain garden, infiltration trench and so on. Also It is the infrastructures using natural mechanisms of soils, microorganisms, plants and animals on a water circulation system and pollutant reduction. In this research, a multi functional GSI technology with infiltration-filtration mechanisms has been developed and performed lab-scale tests to evaluate the performances about infiltration rate restoration and pollutant reduction. The most of pollutants including metals, organics and particulates were reduced about 50~90% due to water infiltration and storage functions. The clogging was found when the TSS loading rate was reached on $8.3{\sim}9.0kg/m^2$, which value is higher than the values in literatures. It means the new technology can show high performances with low maintenances.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.2
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• pp.140-145
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• 1990

This study was carried out to evaluate the possibllity of composting from cow manure using earthworms. In order to rear earthworms safely and control moisture soil was used as conditioner. Fusarium oxysporum and Fusarium sp.1 were isolated from soil and two isolates of Bacillus sp. were selected as antagonists from earthworm casts. By rearing earthworm, C/N ratio was reduced by 40.9% and 41.9% after 28 days, reducing sugar was also decreased by 37.1% and 37.5%. On the other hand, reduction of C/N ratio in cow manure alone was 9.67% and reducing sugar was 12.01%, respectively. Bacillus sp. was apparently increased in earthworm casts than in ordinary soil. It seemed that the earthworm casts contained antibiotic subatance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.104-112
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• 2020

Maize is thought to be an alternative crop to rice in paddy fields for efficient field management and maintenance of rice production at appropriate levels in Korea. Thus efforts to breed waterlogging-tolerant maize cultivars have been ongoing. However, molecular studies related to waterlogging tolerance are limited for developing molecular markers to select waterlogging tolerant maize varieties. In this study, we examined molecular biological changes of B73 in the V3 stage after immersion treatment for 7 days. Overall growth of maize was lower in treated samples compared to non-immersed control samples. The length of leaf and root decreased by 21.3% and 50.6%, respectively and the weight of root reduced by 21.6%. Soil plant analysis development (SPAD) value and chlorophyll content of leaf also decreased by 55.7% and 35.3%, respectively. Reactive oxygen species (ROS) content of root increased by 46.5% at 2 hours in immersion treatment. In addition, immersed roots were 2.5-fold thickened with additional aerenchyma formation in the cortex. In order to identify the causes of these changes, we performed a microarray and found increased expression of genes, such as WIP1, PMIP2, EXPA1, TPS1, and MAS1, in immersed samples. These differentially expressed genes and expression of previously reported genes, including ALDH2, Wusl1032, UP-1, UP-2, and CAT2 were further confirmed with qRT-PCR. Here, we report 7 differentially expressed genes after immersing treatment, which may be utilized as useful resources for breeding waterlogging- tolerant maize.

• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.59-67
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• 1993

This study was conducted to clarify the translocation and the phytotoxicity of soil treated Heptachlor (0.1ppm) and Heptachlor epoxide (0.1ppm) on Hop plants and Hansam vine. Residues in the soils and the plants were analyzed and phytotoxic patterns were investigated at the different growing stages. Photosynthetic rate and chlorophyll contents were measured. The results were summarized as follows: 1. At the second growing stage, 40 days after transplanting, severe damages by Heptachlor were observed on root of Hop. Growth rate on top and root parts of Hop was retarded from the third growing stage, 70 days after transplanting. The damages seemed to be caused by Heptachlor epoxide rather than by Heptachlor. 2. Residues of Heptachlor and Heptachlor epoxide in the plants, Hops and Hansam vine, were high at the second growing stage in comparison with those at the other stages. Residual levels in the plant parts were in order of root> stem> leaf. 3. Inhibition of photosynthetic rate was more serious in Hop plants than those in Hansam vine. The photosynthetic rate was suppressed at the second growing stage by Heptachlor epoxide and greatly reduced at the third growing stage. 4. Chlorophyll contents were not significantly changed in Hops and Hansam vine. Decreasing trends of the chlorophyll contents in both plants treated with the pesticides were similar to those of control plants.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.295-298
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• 2007

In order to sterilize Bacillus cereus and Enterobacter sakazakii in rice flour, hot-air drying ($65^{\circ}C$/15 min, HT) and microwave drying (700 watt/30 sec, MT) treatments were evaluated and a storage study performed. Color changes (${\Delta}E$) appeared to be less in the MT rice flour than in HT treated rice flour. The effectiveness of the MT treatment showed reduced growth rates for B. cereus (0.54 log CFU/g) and E. sakazakii (1.45 log CFU/g). The populations of B. cereus in the control (NT) rice flour greatly increased during storage at 4, 10 and $20^{\circ}C$ as storage times increased. However, the growth of B. cereus was minimized in the MT rice flour. In conclusion, MT treatment is considered to be a good drying method when substituted for HT treatment to assure microbial safety in rice flour.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3285-3294
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• 2012

A field test on mud flat remediation was carried out in order to observe the effects of the treatments such as microbial dose and an oxygen releasing compound like $CaO_2$. The size of each treatment site was $100m^2$ and the dosage was 3.6 kg per site. The 6 week monitoring showed that pH on two sites was below 7 and ORP increased from .178~-188 mV to .121~-142 mV. In Ignition loss and COD there were no significant changes. Meanwhile nitrogen and phosphorus concentrations changed: ammonia concentration decreased both on control and treatment sites. Nitrate nitrogen decreased more on combined treatment site than on single microbial treatment (11.3% vs. 7.3%) probably because the extra oxygen supplied by $CaO_2$ formed more oxic environment so that the facilitated nitrification might produce more nitrate but the nitrate would be much rapidly released into the water layer out of the sediment. That also explains the total nitrogen reduction(6.1%). Similarly, T-P and $PO_4-P$ reduced by 29% and 31.8%, respectively on combined treatment sites, resulting from the phosphorus release effect though the initial concentrations of the two factors were considerably high.

• Journal of Korean Neurosurgical Society
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• v.29 no.6
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• pp.754-762
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• 2000

Objectives : The surgical results of 80 patients with growth hormone(GH)-producing pituitary adenoma were analyzed retrospectively to evaluate the clinical manifestations and to determine which preoperative factors significantly influenced the surgical outcome. Patients and Methods : The patients consisted of 39 men and 41 women and the age of patients at the time of initial operation ranged from 17 to 67 years(mean age, 40.5 years) Between January 1990 and June 1996, 77 patients underwent transsphenoidal surgery and 3 patients underwent craniotomy for GH-producing pituitary adenoma at our institution. Preoperative administration of octreotide was performed in 18 patients. Surgical control was defined as a postoperative serum basal level of GH less than 5ng/ml. A logistic regression model was used for univariate and multivariate analysis. Probability value of less than 0.05 was considered as statistically significant. Results : The most common presenting symptom was acromegaly, followed by headache, visual disturbance, and fatigability. Visual symptoms were present in 39% of the patients. Diabetes mellitus was associated in 24 patients and hypertension in 12. Preoperative mean basal level of GH was 93.2ng/ml(range 72-500ng/ml) which was closely related with tumor size(p<0.05). Grade II by Hardy's classification was the most common radiological type. Preoperative octreotide treatment significantly reduced the level of GH(p<0.05), but not enough to induce endocrinological remission. One patient died of cerebral infarction after craniotomy. The most common surgical complication was transient diabetes insipidus. The symptom of the earliest improvement after surgery was paresthesia and tightness of the hand and foot, followed by headache and easy fatigability. The preoperative visual symptom was improved in all patients. The patients who had hypertension or DM experienced alleviated symptoms in 67% and 92%, respectively. The overall rate of endocrinological remission was 44%. By multivariate logistic regression analysis, the size of tumor, extrasellar extension, and extent of removal were significant prognostic factors for endocrinologial remission. Conclusion : Early detection of a small tumor without extrasellar extension followed by a complete resection is highly recommended in order to achieve endocrinological cure of GH-producing pituitary adenomas.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.617-628
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• 1998

In order to understand the pathogenetic mechanism of adult respiratory distress syndrome (ARDS), the role of phospholipase A2 (PLA2) in association with oxidative stress was investigated in rats. $Interleukin-1{\alpha}\;(IL-1,\;50\;{\mu}g/rat)$ was used to induce acute lung injury by neutrophilic respiratory burst. Five hours after IL-1 insufflation into trachea, microvascular integrity was disrupted, and protein leakage into the alveolar lumen was followed. An infiltration of neutrophils was clearly observed after IL-1 treatment. It was the origin of the generation of oxygen radicals causing oxidative stress in the lung. IL-1 increased tumor necrosis factor (TNF) and cytokine-induced neutrophil chemoattractant (CINC) in the bronchoalveolar lavage fluid, but mepacrine, a PLA2 inhibitor, did not change the levels of these cytokines. Although IL-1 increased PLA2 activity time-dependently, mepacrine inhibited the activity almost completely. Activation of PLA2 elevated leukotriene C4 and B4 (LTC4 and LTB4), and 6-keto-prostaglandin $F2{\alpha}\;(6-keto-PGF2{\alpha})$ was consumed completely by respiratory burst induced by IL-1. Mepacrine did not alter these changes in the contents of lipid mediators. To estimate the functional changes of alveolar barrier during the oxidative stress, quantitative changes of pulmonary surfactant, activity of gamma glutamyltransferase (GGT), and ultrastructural changes were examined. IL-1 increased the level of phospholipid in the bronchoalveolar lavage (BAL) fluid, which seemed to be caused by abnormal, pathological release of lamellar bodies into the alveolar lumen. Mepacrine recovered the amount of surfactant up to control level. IL-1 decreased GGT activity, while mepacrine restored it. In ultrastructural study, when treated with IL-1, marked necroses of endothelial cells and type II pneumocytes were observed, while mepacrine inhibited these pathological changes. In histochemical electron microscopy, increased generation of oxidants was identified around neutrophils and in the cytoplasm of type II pneumocytes. Mepacrine reduced the generation of oxidants in the tissue produced by neutrophilic respiratory burst. In immunoelectron microscopic study, PLA2 was identified in the cytoplasm of the type II pneumocytes after IL-1 treatment, but mepacrine diminished PLA2 particles in the cytoplasm of the type II pneumocyte. Based on these experimental results, it is suggested that PLA2 plays a pivotal role in inducing acute lung injury mediated by IL-1 through the oxidative stress by neutrophils. By causing endothelial damage, functional changes of pulmonary surfactant and alveolar type I pneumocyte, oxidative stress disrupts microvascular integrity and alveolar barrier.

• Resources Recycling
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• v.9 no.1
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• pp.52-62
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• 2000

In order to maximize the recycling of converter slag to the more valuable fields, such as high quality aggregates for construction, cement industry and flux for ion making. It will be very important to control the compositions and properties of converter slag to suit the purpose of utilizastion. In this study, converter slag (STELCO, CANADA) was mixed with 5%~30% $SiO_2$and 7% carbon, and then reduced at $1650^{\circ}C$. After the reduction was completed, the reformed slags were cooled to room temperature in the furnace. All of the slags were then characterized using SEM-EDX, XRD and chemical analysis. Also the compressive strengths and densities of the reformed slags were measured to compare with natural aggregates. XRD analysis shows that th phases of reformed slags are changed from bredigite+merwinite mixed phases of 10% $SiO_2$added reduction to akermanite phases of 20% and 30% $SiO_2$ added reduction. But the SEM-EDX analysis revealed that the phase distribution of the reformed slags was changed very sensitively and complicately depends on the change of slag compositions. And also the properties of reformed slags are changed very much depend on the phase distribution. About one third of Cadmium and on fifth of Vanadium are remained in reduction reformed converter slag. Another heavy metal elements such as cobalt, zinc, lead are removed up to more than 90-95% of original slag. The compressive strength and density of 25% $SiO_2$ added and reformed slag is very near to natural granite. This is superior more than 10% to Thyssen's $SiO_2$ added and oxidized converter slag aggregates.

• Journal of Korea Water Resources Association
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• v.47 no.10
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• pp.973-983
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• 2014

This study focused on the selection of appropriate plant species of VFS (vegetative fiter strips) and the assessment of VFS effects for reducing NPS (non-point source) pollution from uplands. The experimental field was constructed with 1 control and 6 treated plots in the upland area of $1,500m^2$ with 5% slope which is located in Gunwi-gun, Gyeongbuk province. Six vegetation including Chufa, Common crabgrass, Barnyard grass, Turf grass, Tall fescue, Kenturky bluegrass, were applied to install VFS systems during the study period from June 2011 to Dec. 2012. The results of this study showed that 6.1~77.8% in runoff and 15.6~90.3% in TS, 49.9~96.6% in T-P, and 6.7~91.1% in T-N were reduced from the VFS treated plots. Generally high reduction effects were observed from TS, T-P, T-N, and SS, while BOD, TOC, and $NO_3^-$ showed low reductions. The best vegetation type was Turf grass showing higher reduction effects of NPS pollutions and having relatively easier maintenance efforts compared to other vegetations selected in this study. Based on these results, VFS technique found to be an effective management practice for reducing agricultural NPS pollutions in Korean upland conditions. Further study needs to be performed through various field experiments with long term monitoring in order to develop a design manual of VFS system for practical applications.