• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.3
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• pp.139-144
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• 2005

To investigate the long-term variation of water qualities, we have daily monitored physio-chemical characteristics of surface water in the Geum River estuary from June 1996 to April 2004. We found that the water qualities were determined by three dominant factors : 1. fluvial input from Geum River ($28.3\%$), 2. chemical processes such as nitrification and phosphate addition originated from sediment resuspension and domestic sew- age input ($18.6\%$), 3. biological processes such as nutrient consumption by primary producers ($13.5\%$). The factor 1 (fluvial input) effectively affected the water quality of the estuary particularly during the normal or low river discharge. The factor 2 (chemical processes) and the factor 3 (biological processes) showed distinct seasonal differences due to their relative strengths of biological activities. The factor 3 was a governing parameter during the period of spring algal bloom in 2004. For the spring period, an empirical equation derived from the multi-regression analyses showed that the in-situ chlorophyll-a distributions in the estuarine water were successfully simulated by the phosphate concentrations and N/P ratios. Therefore we suggest that phosphate functions as a limiting factor for the primary productivity in the Geum River estuary for the dry season, especially during spring.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.11-18
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• 2016

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. $\small{D}$-xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of $\small{D}$-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with $\small{D}$-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with $\small{D}$-xylose. These groups were maintained for two weeks. The effects of $\small{D}$-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ${\beta}$-cells were analyzed. RESULTS: In vivo, $\small{D}$-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. $\small{D}$-xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of $\small{D}$-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with $\small{D}$-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, $\small{D}$-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, $\small{D}$-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ${\beta}$-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.441-454
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• 2018

Since the permanent shutdown of Kori Unit 1 in 2017, a full-scale decommissioning project for a commercial nuclear reactor has been approaching. It is estimated that about 160,000 t of low-activity concrete waste will be produced from decommissioning of one unit of this commercial nuclear power reactor. Accordingly, it is necessary to review whether the effectiveness of the current regulatory framework for clearance waste (i.e. waste stream that meets activity concentration guidelines or dose criteria for clearance set forth in NSSC Notice No. 2017-65) can be maintained for the clearance of a bulk amount of concrete waste. In this regard, the IAEA SRS No. 44, which was used as a basis for revision of the Korean clearance regulations, is thoroughly analyzed and the radiological effects from four different clearance scenarios, along with input values and parameters derived from industrial practices in Korea, were evaluated. Though it is shown that the maximum annual dose from most recycling scenarios will be less than the clearance dose criterion for the normal scenario (i.e. an order of magnitude of $0.01mSv{\cdot}y^{-1}$), the radiation dose, estimated with conservative assumptions for the banking scenario, may exceed the above clearance dose criteria. Therefore, for safe and sustainable clearance of the bulk amount of concrete waste, it is required to diversify the concrete waste processors, perform more detailed site-specific assessment, and apply limiting conditions to the banking scenario.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.51-51
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• 2001

Cocaine and amphetamine-regulated transcript (CART) is a satiety factor that is regulated by leptin. It was reported that the mice intracerebroventricularly injected with CART showed behavioral changes resembled with the typical behavioral alterations found in the mice carrying disorders in the brain serotonergic (5-HT) system. Hence, this study was conducted to find out the relationships between CART and 5-HT. We first examined the mRNA levels of CART after the injections of para-chlorophenylalanine (pCPA, 300 mg/kg i.p., single injection or daily for three consecutive days) in the rat brains by in situ hybridization using the mouse CART cDNA probe cloned in our laboratory. Systemic administrations of pCPA, a potent inhibitor of tryptophan hydroxylase, the rate limiting enzyme of 5-HT biosynthesis, acutely depletes the brain 5-HT transporter (5-HTT) in the dorsal raphe nucleus (DRN), which reuptakes terminal 5-HT. Results indicated that the mRNA level of CART significantly decreased in the arcuate nucleus, paraventricular nucleus, and lateral hypothalamic nucleus by three days of daily injection with pCPA with no noticeable change detected 24 hrs after the single injection. The message levels of 5-HTT in DRN decreased in both single and three days of injections. Secondly, to investigate whether CART affect to 5-HT, mouse genomic CART gene, which is consist of 3 exons and 2 introns and mouse neurofilament light (NF-L) chain promoter were cloned. Then, we constructed neuron specific expression vector, which was transfected into HeLa cell using lipid-mediated transfection system. Expression of GFP and CART linked to NF-L-chain promoter in the transfected HeLa cell were detected by using fluorescent microscope and RT-PCR. These results confirmed normal expression of DNA constructs in vitro. Then, to increase brain specific expression of CART in vivo transgenic mice carrying CART gene controlled the deleted NF-L-chain promoter were generated by the DNA microinjection into pronuclei of fertilized embryos. Transgenic mice were detected by Southern blot. Further study is necessary to examine CART expression and 5-HTT in these transgenic mice. Therefore, these results suggest that there maybe a positive molecular correlation between CART and 5-HT in responding to the stimuli.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.4
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• pp.519-534
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• 2019

When the fresh water from the artificial lakes (Ganwolho and Bunamho) were discharged to Cheonsu Bay in summer to prevent the flood over the reclaimed farmland near the lakes, the impact on water qualities (nutrients, organic matters, trace metals) within the bay was investigated through four surveys (June, July, August and October, 2011). Dissolved inorganic nitrogen (DIN) increased about as much as 3-4 times over the whole water column when the freshwater was discharged. And the main species composition of DIN changed from ammonia to nitrate. Dissolved inorganic phosphorus (DIP) decreased as much as 2 times in surface waters, but increased as much as 1.5 times in deep waters, and also silicate concentrations increased as much as 3-4 times in deep waters of the inner bay. The N/P ratios in Chunsu bay seawaters were much higher (2 to 7 times) than the Redfield ratio when the freshwaters were discharged, which indicated the phosphorus limiting in the phytoplankton growth. Dissolved organic carbon (DOC) and nitrogen (DON) increased as much as about 2 times. In addition, particulate organic matters (POC, PON, POP, Bio-Si) increased as much as above 2 times in the surface waters of the inner bay. Trace metals (Fe, Mn, Co, Ni, Cu) increased in the surface waters of the inner bay, but dissolved Cd concentrations decreased as much as 2 times. Therefore, when the contaminated fresh waters from the artificial lakes were discharged into the bay, nutrients, organic matters and trace metals generally increased compared to normal period. Since the phytoplankton bloom occurred in the surface waters of the inner bay, dissolved oxygens at the surface waters were oversaturated and hence hypoxic in the deep waters. Highly enriched nutrients concentrations were found in deep waters of the inner bay, which was accompanied with the hypoxic condition. Finally, the water quality in the inner bay of the Chunsu bay was deteriorated from less than grade 3 in normal periods to grade 5 when the freshwaters from the artificial lakes were discharged in summer.

• The Journal of Internal Korean Medicine
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• v.35 no.1
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• pp.92-105
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• 2014

Objectives : Cisplatin is a widely used cancer therapy drug. However, nephrotoxicity resulting in increased oxidative stress is a major side effect of cisplatin chemotherapy, thereby limiting its chemotherapeutic use. Lycium chinense Miller (LCM) has been used as a traditional herbal medicine in various febrile and inflammatory diseases such as night sweat, cough, nosebleed, bronchitis, pulmonary tuberculosis, etc. In this study we investigated the protective and antioxidative potential of LCM against cisplatin-induced nephrotoxicity in rats. Methods : Twenty-four 8-week-old male Wistar rats were divided into four groups: normal untreated; cisplatin treatment only; LCM 10 mg/kg plus cisplatin treatment; and LCM 30 mg/kg plus cisplatin treatment. Twenty-four hours after the last cisplatin injection, all the rats were sacrificed, and serological changes were evaluated. The levels of NF-${\kappa}B$ activity and NOX-4, $p47^{phox}$, $p22^{phox}$, COX-2, iNOS, SOD, catalase expressions were analyzed in Western blot analysis. Results : Cisplatin injection caused an increase in the BUN level, which is a reliable indicator of renal toxicity. The levels of BUN, renal ROS, and renal TBARS were significantly reduced in the LCM groups compared with the cisplatin-only groups. The levels of $p47^{phox}$ and $p22^{phox}$, which are NADPH oxidase subunits, were increased in the cisplatin-only groups, whereas they were decreased in the LCM groups. The levels of renal NF-${\kappa}B$ activity and COX-2, iNOS expressions were increased significantly in the cisplatin-only groups compared with the normal groups, whereas they were decreased in the LCM groups. Compared with the cisplatin-only groups, renal GSH and GSH/GSSG increased in the LCM groups. Also, the administration of LCM increased levels of SOD and catalase as compared with the cisplatin-only groups. Conclusions : These results suggest that LCM protects cisplatin-induced nephrotoxicity via a mechanism that may involves the inhibition of oxidative stress by the activation of antioxidants.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.329-336
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• 2014

As an abiotic stress, chilling stress is one of the major factors limiting plant growth and increasing susceptibility to pathogens. Therefore, enhancing stress tolerance in plants is an important strategy for their survival under unfavorable environmental conditions. The objective of this study was to determine the effects of the exogenous application of salicylic acid (SA) or nitric oxide (NO) on chilling tolerance in pepper seedlings. Pepper (Capsicum annuum L. 'kidaemanbal') seedlings were grown under normal growing conditions ($20/25^{\circ}C$, 15 hours photoperiod, $145{\pm}5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, fluorescence lamps) for 23 days after transplanting. The solution (3 mL) of 1 mM SA and 0.3 mM NO with surfactant triton 0.1% were sprayed two times a week, respectively. Right after the completion of chemical application, seedlings were subjected to chilling condition at $4^{\circ}C$ for 6 hours under dark condition and then the seedlings were recovered at the normal growing conditions for 2 days. In order to assess plant tolerance against chilling stress, growth characteristics, chlorophyll fluorescence (Fv/Fm), and membrane permeability were determined after chilling stress imposition. Total phenolic concentration and antioxidant capacity were measured during the whole experimental period. Disease incidence for pepper bacterial spot and wilt was also analyzed. Pepper seedlings treated with SA or NO were maintained similar dry mass ratio, while the value in control increased caused by chilling stress suggesting relatively more water loss in control plants. Electrolyte leakage of pepper seedlings treated with SA or NO was lower than that of control 2 days after chilling treatment. Fv/Fm rapidly decreased after chilling stress in control while the value of SA or NO was maintained about 0.8. SA increased higher total phenolic concentration and antioxidant capacity than NO and control during chemical treatment. In addition, increase in total phenolic concentration was observed after chilling stress in control and NO treatment. SA had an effect on the reduction of bacterial wilt in pepper seedlings. The results from this study revealed that pre-treatment with SA or NO using foliar spray was effective in chilling tolerance and the reduction of disease incidence in pepper seedlings.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.33-44
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• 2014

Purpose: Elevated serum phosphorus and potassium levels are a major problem for hemodialysis (HD) patients. Hyperphosphatemia and hyperkalemia are closely related to intake of dietary phosphorus and potassium. Methods: This study was conducted in order to investigate the effects of food consumed on serum phosphorus and potassium levels in 48 HD patients (20 males and 28 females). We collected anthropometric data, biochemical parameters, and dietary data of the subjects. Dietary data for usual intake were obtained by use of a food-frequency questionnaire (FFQ) consisting of 21 food items. Results: The mean body mass index (BMI) was $22.2{\pm}3.0kg/m^2$, mean serum phosphorus level was $4.50{\pm}1.52mg/dl$, and mean serum potassium level was $4.74{\pm}0.73mEq/l$. Hyperphosphatemia (> 4.5 mg/dl) was found in 45.8% of subjects, and hyperkalemia (> 5.0 mEq/l) in 35.4%. Subjects who took medication only were 56% of total, and those who took medication with dietary therapy were 27%. Patients with medication and dietary therapy showed significantly lower serum phosphorus levels compared to patients with medication only (p < 0.05). Mean duration of HD was $7.9{\pm}7.3$ years and it showed positive correlation with serum potassium levels (p < 0.05). Serum phosphorus levels showed positive correlation with intake of mixed grains and soybean milk (p < 0.05). Serum potassium levels showed positive correlation with intake of mixed grains (p < 0.01), potatoes, fish, and high-potassium vegetables (p < 0.05). On the other hand, intake of white rice showed negative correlation with serum potassium levels (p < 0.05). Conclusion: The results of our study suggest that intake of white rice rather than mixed grains is an important factor in sustaining normal serum phosphorus and potassium levels. In addition, limiting intake of soybean milk, potatoes, and fish to under three serving per week is recommended. Finally, conduct of a strict dietary therapy along with medical treatment is desirable because inappropriate food intake increases serum phosphorus and potassium levels to a higher than normal range.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.1
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• pp.49-54
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• 2002

Purpose : To analyze the clinical results of treatment for the osteochondritis dissecans of femoral condyle by age, the type of lesion and method of treatment. Methods : From March 1991 to February 2000, 17 patients (20 cases) with osteochondritis dissecans of the femoral condyle were followed up over 1 year. Three patients had bilateral lesion. There were 12 cases with trauma history (9 cases with sports injury and 3 cases with direct trauma). The initial symptoms were pain, clicking, locking, giving way in the order of frequency, pain was revealed in all cases. Clinical evaluation of IKDC and Hughston method were used for subjective and objective function. Results : The number of male patient was 12, and the mean age was 19.8 year old (11$\~$50). The location of the lesion was 14 cases in medial femoral condyle and 6 cases in lateral femoral condyle. The arthroscopic findings of the lesion in 15 cases were as follows, early separation in 6 cases, partially detachment in 4 cases, and crators and complete detachment in 5 cases. 5 cases were treated with mutiple drilling and 5 cases with Herbert screw fixation, 3 cases with Herbert screw fixation and bone graft. In early stage, 7 cases were treated with conservative method. In the grading of Hughston score, 6 cases were graded as excellent, 9 cases as good, 15 cases were graded as good to excellent. Based on the IKDC scale, 1 case was graded as normal, 6 as nearly normal, and 10 as abnormal. Conclusions : The trauma seemed to be important factor in occurrence of osteochondritis dissecans of the femoral condyle. The clinical results of juvenile period showed better than adolescence and adult period, it is necessary to detect the lesion as soon as possible. The result of subjective evaluation was worse than the Hughston evaluation. It was caused by limiting involvement of sports activity and limited activity in the adolescence.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.125-135
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• 1994

Field experiment was carried out in order to clarify effects of plastic film mulching on temperature and moisture of rhizosphere soil and their subsequent effects on seedling emergence, earlier growth, vegetative growth and grain yield of sesame. The textural class of the experimental field soil was the sandy loam(Bonyang series) and the variety of sesame planted was "Ansan-ggae". The experiment was conducted by combining four sowing dates of April 25, May 10, May 25, June 10 and two mulching treatments(mulching, non-mulching) over two year of 1991 and 1992. The results were summarized as follows : 1. The daily mean soil temperature of 5cm deep soil was increased by 1.4 to $2.8^{\circ}C$ by plastic film mulching. The average soil water content was increased by 0.5 to 3.0%(V/V) in the drier season, while decreased by 1.0 to 2.0%(V/V) in the rainy season by mulching. 2. The establishment rate of sesame seedling was very sensitive to soil temperature. For normal seedling emergence, from the seeding date to the 7th date after sowing, the daily mean soil temperature higher than $21.0^{\circ}C$ was required at the experimental field conditions. 3. The average soil water content in the range of 14.0 to 21.0%(V/V) at 5cm deep soil seemed not to be limiting for the germination and emergence of sesame. The effect of soil water content on seedling establishment was very small in this range, but the optimum level of soil water content ranged from 14.0 to 15.0%(V/V) in the experimented sandy loam. 4. The wetter the soil profile was, the larger the gap of soil temperature between the mulched and non-mulched condition was. The effect of mulching on the establishment rate of sesame seedlings was much greater in the lower air temperature conditions. However, when the sowing of sesame came earlier than at the date with the daily mean air temperature below $19.0^{\circ}C$, the effects of earlier sowing and mulching were offsetted by the retarded seedling growth due to the low air temperature, and thus earlier sowing with mulching did not enhance the grain yield of sesame.