• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.137-145
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• 2008

In this study, to reduce the flood damage caused by flood discharge exceeding project flood, the primary technology was applied to determining the optimal location and size for underground sluiceway. The Jungrang Stream was selected for this study because the stream was overflowed and the embankment section of the stream was destroyed owing to localized torrential rainfall in 1998 and 2001. Considering 200-year frequency storm, the inlets of the underground discharge channel were located at Seoul City limits, the confluence of Danghyun Stream, Wolgye 1-gyo, and the confluence of Mukdong Stream. The outlets were located at the estuary of Jungrang Stream and rightbank of Banpo Bridge in Han River. The transverse discharge according to the variation of overflow depth at the inlet of underground discharge channel was estimated and the effect of inundation reduction was analyzed. To examine the appropriate scale of the underground discharge channel, the 8 operation methods for the management of outlet discharge were compared considering four rules (only storage, the constant discharge rate, the constant discharge volume, and the mixture of the constant discharge rate and discharge volume). As a result, the effect of inundation reduction was most significantly improved when the inlet was located at the confluence of Danghyun Stream. The appropriate size of underground sluiceway for 200-year frequency storm was studied, and as a result, the appropriate diameters of the underground discharge channel were 12 m in case of only storage(Rule D), 9m in 50% of discharge(Rule E), 8 m in constant discharge volume(Rule F), and 7 m in mixture method(Rule G). This investigation process can be applied to design the underground discharge channel when the inundation damage is significant in coastal area due to embankment overflow. The underground discharge channel in Jungrang Stream can also be used as an underground road to link Seoul City to Uijeongbu City during dry season.

• KSBB Journal
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• v.23 no.3
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• pp.205-212
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• 2008

The efficient soluble expression of human epidermal growth factor (hEGF) was achieved by using functional fusion partners in cytoplasm and periplasm of Escherichia coli (E. coli). hEGF was over-expressed in inactive inclusion body form in cytoplasm of E. coli due to improper disulfide bond formation and hydrophobic interaction, yielding about 5.9 mg/L in flask culture. Six functional fusion partners were introduced by linking to N-terminal part of hEGF gene for the high-level expression of soluble and active hEGF in cytoplasm and peri plasm region. Three fusion partners for cytoplasmic expression such as acidic tail of synuclein (ATS), thioredoxin (Trx) and lipase, and three fusion partners for periplasmic expression such as periplasmic cystein oxidoreductases (DsbA and DsbC) and maltose binding protein (MBP) were investigated. hEGF fused with ATS and DsbA showed over 90% of solubility in cytoplasm and periplasm, respectively. Especially DsbA was found to be an efficient fusion partner for soluble and high-level expression of hEGF, yielding about 18.1 mg/L and three-fold higher level compared to that of insoluble non-fusion hEGF in cytoplasm. Thus, heterologous proteins containing complex disulfide bond and many hydrophobic amino acids can effectively be produced as an active form in E. coli by introducing a suitable peptide or protein.

• The Journal of Engineering Geology
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• v.19 no.2
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• pp.235-250
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• 2009

Environmental elements such as B, Br, and Sr in groundwater from Bukahn-myeon, Yeongcheon, Gyeongbuk Province, were investigated in order to know their origin with emphasis on hydrochemistry. pH ranges from 7.37 to 8.39. B content is 0.41${\sim}$4.62 mg/L with an average 1.74 mg/L and Br content is 0${\sim}$3.24 mg/L with an average 2.22 mg/L, and Sr content is 0.93${\sim}$8.64 mg/L with an average 2.76 mg/L. The water types plotted by the Piper diagram are different but mostly $Ca-HCO_3$. Some constituents contributing to EC are Na, $SO_4$, Cl with high determinative coefficients($R^2$) of 0.85, 0.70, 0.90, respectively. The coefficients($R^2$) of Cl to Na, K, $SO_4$ are 0.54, 0.68, 0.53, respectively. It should be noted that there are high cocfficients($R^2$) of B-Sr and $Sr-SO_4$ with 0.65, 0.64, respectively. The Cl/Br ratios are 5.21${\sim}$30.70 due to significant depletion of Cl. The $SO_4/Cl$ ratios are 1.32${\sim}$27.24 with an average of 5.92, ascribed to abundant introduction of $SO_4$ or significant depletion of Cl. Chemical speciation calculated shows that B exists mostly as $H_3BO_3$ with less $H_2BO^-_3$ and Br exists as only $Br^-$. Sr exists mostly as $Sr^2$ with less $SO_4$. Saturation index represents that goundwater is supersaturated with respect to barite, kaolinite, illite, K-mica, and smectite while it is slightly undersaturated with respect to silica, gypsum, anhydrite, talc, chrysotile, feldspar, kaolinite, illite, K-mica, and smectite. The saturation index of celestine is -2.23${\sim}$-0.13 indicating more Sr can be incorporated into groundwater. Groundwater is still much undersaturated to halite. It is likely that the origin of S and Sr was related to the Yucheon volcanic rocks. Br might be originated from the local geological features with introduction of anthropogenic matters.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.101-115
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• 2018

This study was carried out to evaluate the effects of various filter conditions on unconfined aquifer (alluvial aquifer). We made model test device which has filter layer, pumping well and observation well which consist of sand layer and gravel layer to test. Step drawdown test and long term pumping tests were carried out using the device. The permeability characteristics of each test group were confirmed and the optimal yield was calculated. As a result of comparing the optimal yield of double filter and single filter in sand, dual-filter SD-300 was valued at 216.8 % higher final optimal yield than single-filter SS-300. Comparing the dual filter SD-300 and the single filter SS-100 with a thin filter layer, dual-filter SD-300 was valued at 709.2% higher final optimal yield than single-filter SS-300. As a result of analysis of optimal yield change over time, It was confirmed that the ratio of optimal yield of single filter and dual filter increase over time. In order to evaluate the long-term change in water intake efficiency, we considered the point at which the initial optimal yield was reduced by 50%. The dual filter SD-300 is about 351.1% higher than SS-300, which is the same thickness filter, and about 579.0% higher than SS-100. From these results, Assuming that the point at which the initial quantity of water intake is reduced to 50% is the well life, double filters are expected to increase their lifespan by about 3.5 times over single filters of the same thickness and by about 5.8 times over typical single filter. These results can be used to design wells to river bank filtration or filtered seawater. In addition, it is possible to clarify the effect of the double filter through the comparison with the future field test results.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.296-306
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• 2014

This study was conducted to survey and analyze the quantity of various organic wastes and to vitalize the utilization of agri-food by-products as raw materials for Total mixed ration (TMR), to improve feed cost savings and the quality of animal products. On-the-spot obstacles for animal farmers, along with legal and institutional alternatives are presented. The results are as follows. First, organic wastes in Korea are managed by the Allbaro system created in the Wastes Control Act, which processes 10,488 tons of cooking oil waste, 832,493 tons of animal and plant residues, 5,740 tons of animal carcasses, 1,171,892 tons of animal residues, and 2,172,415 tons of plant residues including 12,905 tons of rice hull and bran, for a total of 4,205,931 tons. Raw materials for TMR, namely rice hulls and bran as well as plant residues, accounted for 51.7% of the total national organic waste. The top 10 municipalities process 76~100% of all organic wastes and a supply management system is needed for the waste. Second, the 10 major agri-food by-products used as raw materials for TMR are bean curd by-product, rice bran, oil-cake, brewers dried grain, Distiller's Dried Grains with Solubles (DDGS), barley bran, soy sauce by-product, citrus fruit by-product, mushroom by-product and other food by-product (bread, noodles, snacks, etc.). Third, the biggest difficulties in using agri-food by-products are legal obstacles. Because agri-food by-products are regulated as industrial wastes by the Waste Control Act, animal farmers that wish to use them have legal reporting obligations including the installation of recycling facilities. To enable the use of agri-food by-products as raw materials for TMR, waste management system improvements such as 'the end of waste status' and the establishment of more than 10 public distribution centers nationwide are deemed essential.

• Tuberculosis and Respiratory Diseases
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• v.47 no.1
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• pp.42-49
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• 1999

Background: In patients with chronic obstructive pulmonary disease(COPD). it is well known that hypoxemia increases the frequency of VPB, which is associated with the poor prognosis such as sudden death. The aim of this study is to evaluate the effect of short and long-term low flow oxygen therapy on the development of VPBs in patients with COPD by correcting the hypoxemia. Method: In 19 patients with COPD, oxygen saturation and VPB's were monitored by pulse oxymeter and 24-hour Holter EKG, with room air and oxygen saturation and VPB's were monitored on the 1st and on the 8th day during oxygen therapy with nasal prong (2L/min). Results : The arterial oxygen saturation was significantly higher on the 1st day of oxygen therapy compared with breathing room air, and was also higher on the 8th day of oxygen therapy than on the 1st day. We found that there was significant correlation between the lowest value of the arterial oxygen saturation and the mean value of the arterial oxygen saturation. The number of VPB's per hour was significantly lower on the 1st day of oxygen therapy compared with breathing room air, and also lower on the 8th day of oxygen therapy than on the 1st day. Our results showed positive correlation between the decrease in the frequency of VPB's and the increase in the lowest arterial oxygen saturation, even though correlation was not significant(p=0.056). Conclusion: With oxygen therapy, the arterial oxygen saturation was increased and the number of VPB's was decreased. Long-term oxygen therapy more than 7days, would be helpful to decrease the number of VPB' s in patients with COPD.

• Journal of Korean Neurosurgical Society
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• v.30 no.5
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• pp.611-621
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• 2001

Objective : We analyzed the clinical and endocrinological results of the transsphenoidal microsurgery for ACTH secreting pituitary adenomas. Marerials and Methods : From October 1995 to August 2000, 18 patients underwent transsphenoidal microsurgery for Cushing's disease. We analyzed the surgical results of 17 patients, one patient who was previously operated from other hospital was excluded. Age of the patients were 18 to 61 years old(mean 37.7), male to female ratio was 1 : 3.3, and follow-up period was 3 to 50 months(mean 20.3). The selection of candidates for transsphenoidal exploration was based on endocrinologic criteria. Magnetic resonance imaging was the preferred radiologic test. Selective inferior petrosal sinus sampling of adrenocorticotropic hormone futher refined the diagnosis when endocrinologic and radiologic procedures were not definitive. Results : Results of the preoperative endocrinological test were : level of serum ACTH 29.4 to $225{\mu}g/dL$(mean $93.88{\mu}g/dL$) ; serum cortisol 11.9 to $47.5{\mu}g/dL$(mean $27.49{\mu}g/dL$) ; 24-hour urine free cortisol 235 to $1019{\mu}g/day$(mean $571.0{\mu}g/day$). Inferior petrosal sinus sampling for ACTH was performed in 11 patients and all were confirmed by Cushing's disease and we could predict the laterality of the tumor in 9 of 11 patients. We performed transsphenoidal selective adenomectomy in 5 patients, adenomectomy and subtotal hypophysectomy in 2 patients, adenomectomy and partial hypophysectomy in 9 patients, and in the remaining one patient, hemihypophysectomy followed by total hypophysectomy due to remission failure. Fifteen of 17 patients(88.2%) showed endocrinological remission. Glucocorticoid replacement therapy was performed in all the patients who showed remission for 1 to 24 months(mean 5.9 months), and 6 patients received steroid over 6 months. Conclusion : We conclude that the direct demonstration of a tumor in the pituitary gland by MRI is the most important and definitive diagnostic tool and the location of a mass should be confirmed with increased level of ACTH by the inferior petrosal sinus sampling. Transsphenoidal microsurgery is effective treatment modality for Cushing's disease and the immediate postoperative evaluation of the surgical resection of the tumor is very important. The patients should show hypocortisolism, decreased, subnormal serum ACTH and cortisol levels and 24-hours urine free cortisol. We performed 18 transsphenoidal microsurgery for Cushing's disease in 17 patients and 15 patients(88.2%) showed endocrinological remission.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1050-1061
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• 2009

The present study was performed to evaluate energy and nutrients intakes of stroke patients in Daegu Gyeongbuk region, and to analyze the relative risk of stroke related to the intake levels of energy and nutrients. The case subjects (n=100) were selected from newly diagnosed stroke patients at Kyungpook National University Hospital. The control subjects (n=150) were selected from community residents who did not have stroke history and were sex and age-matched with the case subjects. The survey was conducted by individual interviews by trained dietitians using semiquantitative food frequency questionnaires. The odds ratios were calculated by using unconditional logistic regression. In male subjects, patient group had significantly higher consumption than the control group in mean daily intakes of energy, all energy yielding nutrients, vitamin $B_1$, $B_6$, niacin, folic acid, vitamin E, phosphorus, potassium, zinc and dietary fiber, and also in the ratio of energy intake from protein and fat. In women subjects, the patient group consumed significantly lower intakes than the control group in fat, vitamin C, folic acid, vitamin E, iron, but vice versa in carbohydrate energy ratio. As for men, the increased intakes of energy, protein, carbohydrate vitamin $B_1$, E and niacin, zinc, total fatty acids, monoand poly-unsaturated, n-6 fatty acids significantly raised the relative risk of stroke. As for women, the increased intakes of fat, vitamin A, $B_2$, $B_6$, niacin, vitamin C and E, iron, sodium, potassium, selenium, mono-, poly-unsaturated, n-6 fatty acids, cholesterol, taurine and dietary fiber significantly lowered the relative risk of stroke. The results of the study demonstrated that the effect of several nutrient intake levels, such as niacin, vitamin E and fatty acids, on the relative risk of stroke was inconsistent between sex. The reason for this sex difference needs to be elucidated in a larger scale study.

• Korean Journal of Remote Sensing
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• v.36 no.2_1
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• pp.121-137
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• 2020

Data from the Ozone Monitoring Instrument (OMI) satellite and national emission inventories were used in this study to analyze air quality in East Asia and estimate the impact of domestic and foreign emissions on South Korea's air quality, based on which future emissions were predicted. The concentration trends of nitrogen dioxide (NO₂) and sulfur dioxide (SO₂) in East Asia from 2005 to 2015 showed that both substances were highest in North East China (NEC), followed by South East China (SEC) and Seoul Metropolitan Area (SMA). The average SO₂ concentration was 1.63 times higher in NEC than in SMA. Analysis on the ratios of NO₂/SO₂ and NO_x/SO_x provides an indirect picture of the effect of transboundary air pollutants on atmospheric composition in Korea. The concentration ratio of NO₂/SO₂ in all study areas peaked in 2013 and SMA's emission ratio of NO_x/SO_x increased in 2015 by over 22% from 2013. Despite the reduction in domestic emissions, the concentration-to-emission ratios (NO₂/NO_x, SO₂/SO_x) rose gradually, which implies that other factors besides domestic emissions (e.g., foreign sources, lifetime, etc.) influence air quality in SMA. We estimated future emissions of NO_x and SO_x in SMA to be 296.2 and 39.0 ktons in 2025 and 284.4 and 33.8 ktons in 2035, respectively. Application of the inter-comparison techniques of this study to the data from the Geostationary Environment Monitoring Instrument (GEMS) is expected to provide concrete information which can be used to improve national emission inventories and figure out factors and sources that affect domestic air quality.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.239-248
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• 2004

This experiment was carried out to confirm that phytochrome regulates anthocyanin bio-synthesis during cell suspension culture system of grape or not. In suspension culture of grape, maximum accumulation of anthocyanin was observed at the stationary phase under continuous white light condition. From mono-chromatic light interruption for 24h at the 4th or 7th day on the suspension cultured cells, the anthocyanin accumulation was highly enhanced at the light interruption at 7th day than 4th day under all monochromatic light treatment. However, the cell growth patterns were not affected by any light treatment. In the darkness, the anthocyanin synthesis was very low but remarkably increased by blue light or red light irradiation. However, the increase of anthocyanin accumulation by blue or red light was suppressed by far-red light in the suspension cells of grape. This suppression by far-red light on the anthocyanin synthesis also observed on the cells treated red or far-red light alternatively. These results implied that phytochrome regulation system may be involved in the anthocyanin biosynthesis of the suspension grape cells. By RNA expression analysis, chalcone synthase (CHS) gene was expressed highly by blue and red light but low by far-red light. The synergistic increase of CHS gene expression was also observed at the treatment of blue light followed by red for 24h. This result may explain the increase of anthocyanin accumulation in B/R treatment. Although the expression of phytochrome gene (PHYA or PHYB) was not highly increased by all light treatment (blue, red, and far-red light) the expression of both PHYA gene and PHYB gene was increased a little in cells treated red or far-red light. In grape suspension cells, the red light enhanced the anthocyanin synthesis, whereas the far-red light was suppressed. Although it was not confirmed whether or not phytochrome gene is activated in anthocyanin accumulating grape cells, we believed that anthocyanin biosynthesis in grape cells may be regulated under phytochrome signal transduction system.