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Temporal and Spatial Distributions of Basic Water Quality in the Upper Regions of Brackish Lake Sihwa with a Limited Water Exchange (물 교환이 제한적인 시화호 상류 기수역에서 기초수질의 시공간적 분포특성)

  • Choi, Kwnag-Soon;Kim, Sea-Won;Kim, Dong-Sup;Oh, Young-Taek;Heo, Woo-Myoung;Lee, Yun-Kyoung;Park, Yong-Soon
    • Korean Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.206-215
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    • 2008
  • Temporal and spatial distributions of salinity, temperature, dissolved oxygen (DO), and turbidity were investigated at seven sites in the upper regions of brackish Lake Sihwa with a limited water exchange, from March to October 2005. During the study period, salinity and temperature varied $0.1{\sim}29.9\;psu$ and $4.7{\sim}28.1^{\circ}C$, respectively, depending on seasons and sites sampled. A distinct halocline profile showing the maximum density gradient (difference over $20\;psu\;m^{-1}$ between surface and bottom layers) was observed during the rainy season, due to the decrease of salinity in surface layers by freshwater inflow. This result implies that rainfall event is the important factor forming the halocline. On the other hand, the depth and location of haloeline varied with the amount of seawater through the sluice gates and the operation systems (inflow or outflow). High DO (over 300% saturation) was observed at surface layer above the halocline in April when red tide occurred, whereas low DO (below 20% saturation) was at the bottom layer below the halocline in the rainy season. Turbidity ranged $1.5{\sim}80.3\;NTU$ showing the maximum turbidity at the layers above or upper the halocline. As a result, the distributions of DO and turbidity in the upper regions of brackish Lake Sihwa were largely affected by the variation of salinity. Also, when the halocline was formed, the water quality between upper and lower water layers may be expected completely different. This study suggests that the physicochemical characteristics of water in the brackish regions are closely associated with the causes of eutrophication such as red tide and DO deficit.

Eutrophication in the Upper Regions of Brackish Lake Sihwa with a Limited Water Exchange (물 교환이 제한적인 시화호 상류 기수역의 부영양화)

  • Choi, Kwnag-Soon;Kim, Sea-Won;Kim, Dong-Sup;Heo, Woo-Myoung;Lee, Yun-Kyoung;Hwang, In-Seo;Lee, Han-Jin
    • Korean Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.216-227
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    • 2008
  • To understand eutrophication in the upper regions of brackish Lake Sihwa with a limited water exchange, temporal and spatial distributions of pollutants in water and sediment were investigated from March to October in 2005 and 2006. Also, pollution levels of water and sediment were estimated by trophic state index (TSI) and sediment quality guideline (SQG). Total nitrogen (TN), total phosphorus (TP), organic matter (COD), and chlorophyll $\alpha$ (Chl-$\alpha$) concentrations in the surface waters were largely varied temporally and spatially, and the variations were highest in the middle areas where strong halocline was formed. Chl-$\alpha$ concentrations in the middle area were very high in April (>$900\;{\mu}g\;L^{-1}$) when algal blooms (red tides) occurred. The relationships between TN and Chl-$\alpha$ (r=0.31), and TP and Chl-$\alpha$ (r=0.65) indicated that the algal growth was primarily affected by phosphorus rather than nitrogen. The distribution of COD was similar to that of Chl-$\alpha$, indicating that the autochthonous organic matters may be a more important carbon source, especially in the middle areas. The brackish water regions were classified as eutrophic or hypertrophic based on their TSI values ($69{\sim}76$). In addition, the content of nutrients (especially TP) in surface sediments were classified as severe polluted state, except the upper areas. Major causes of the eutrophication observed were probably due to high nutrients loading from watersheds, the phosphorus release from anaerobic sediment, and long retention time by the limited water exchange through the sluice gates.

Antioxidative and Biological Activites of Extracts of Sweetpotato Tips (고구마 끝순 추출물이 알코올 투여 흰쥐의 항산화 효소계 및 지질과산화에 미치는 영향)

  • Lee, Joon-Seol;Park, Yang-Kyun;Ahn, Young-Sup;Kim, Hag-Sin;Chung, Mi-Nam;Jeong, Byeong-Choon;Bang, Jin-Ki
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.4
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    • pp.411-420
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    • 2007
  • This study was conducted to increase sweetpotato utilization and to determine the vegetative value of sweetpotato tips by investigating the phenolic compounds, antioxidative effect in oil, electron donating ability, nitrite scavenging effect and ACE inhibition activities. The phenolic compounds present in sweetpotato tips are the gallic, chlorogenic, gentisic, caffeic, couramic and ferulic acid, which are 16-122 times higher compared to other vegetables such as spinach, soybean sprout, and perilla leaves. In each solvent extract, the total phenolic compounds(175.8 mg/g) was composed of 55% EtOAc extraction and 39% BuOH extract, respectively. The results of induction period using the Rancimat method showed that the antioxidant activity of SP tips was higher than the tocopherol or BHT. The relative levels of each solvent extract in SP tips were as follows: EtOAc>BHT>BuOH>Tocopherol>Water>$CHCl_3$>Hexane. The peroxide value was measured every 5 days for 25 days during storage and results showed that the peroxide value, the tips, tuberous root and tocopherol were lower compared to spinach, soybean sprout and perilla leaves. Nitrite scavenging effects were excellent in sweetpotato tips, perilla leaves and soybean sprout, especially, inhibition rate of perilla leaves(72%) were superior to the others. In process of solvent extraction, activity of BuOH and water extractions were the best. ACE inhibition activity in sweetpotato tips was 1.5 times higher than in tuberous roots and $1.9{\sim}3.7$ times higher than in spinach, soybean sprout, perilla leaves.

Growth Characteristic and Nutrient Uptake of Water Plants in Constructed Wetlands for Treating Livestock Wastewater (인공습지를 이용한 축산폐수처리장에서 수생식물의 생육특성과 영양염류 흡수특성)

  • Park, Jong-Hwan;Seo, Dong-Cheol;Kim, Seong-Heon;Lee, Choong-Heon;Choi, Jeong-Ho;Lee, Sang-Won;Lee, Dong-Jin;Ha, Yeong-Rae;Cho, Ju-Sik;Heo, Jong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.31 no.4
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    • pp.351-358
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    • 2012
  • BACKGROUND: Constructed wetlands for wastewater treatment are vegetated by wetland plants. Wetland plants are an important component of wetlands, and the plants have several roles in relation to the livestock wastewater treatment processes. The objectives of this study were to investigate the growth characteristics and nutrient absorption of water plants in constructed wetlands for treating livestock wastewater. METHODS AND RESULTS: In this study, livestock wastewater treatment plant by constructed wetlands consisted of $1^{st}$ water plant filtration bed, $2^{nd}$ activated sludge bed, $3^{rd}$ vertical flow(VF), $4^{th}$ horizontal flow(HF) and $5^{th}$ HF beds. Phragmites communis TRINIUS(PHRCO) was transplanted in $3^{rd}$ VF bed, Iris pseudoacorus L(IRIPS) was transplanted in $4^{th}$ HF bed and PHRCO, IRIPS and Typha orientalis PRESEL(THYOR) were transplanted in $5^{th}$ HF. Growth of water plants in constructed wetlands were the highest in October. The IRIPS growth was higher than other plant as 264 g/plant in October. The absorption of nitrogen and phosphorus by IRIS were 3.38 g/plant and 0.634 g/plant, respectively. The absorption of K, Ca, Mg, Na, Fe, Mn, Cu and Zn by water plants were higher in the order of IRIPS > THYOR > PHRCO. CONCLUSION(S): The absorption of nutrients by water plants were higher on the order of IRIPS > THYOR > PHRCO in constructed wetlands for treating livestock wastewater.

Comparison of Movement Distance and Home Range Size of Gold-spotted Pond Frog (Pelophylax chosenicus) between Rice Paddy and Ecological park - Focus on the Planning Alternative Habitat - (논과 생태공원에서 금개구리 이동 거리 및 서식영역 크기 비교 - 대체서식지 조성 중심으로 -)

  • Park, Su-Gon;Ra, Nam-Yong;Jang, Young-Soo;Woo, Seung Hyun;Koo, Kyo Soung;Chang, Min-Ho
    • Ecology and Resilient Infrastructure
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    • v.6 no.4
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    • pp.200-207
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    • 2019
  • The movement distance and home range size of Pelophylax chosenicus were identified in the rice paddy and ecological park as alternative habitats from July to November 2017. A total of 39 frogs were tracked by radio tracking method. As a result, the average move distance in the population of rice paddy was 11.7 ± 1.9 m (n = 64) and the population of ecological park was 24.7 ± 4.3 m (n = 39). The move distance between the two populations was significantly different. The mean MCP of the population of rice paddy was 181.2 ± 110.8 m2 (n = 11) and the population of ecological park was 416.1 ± 276.2 m2 (n = 10), but there was no significant difference. The population area of rice paddy was 4,160 m2 (Kernel density 95%) and the core area was 1,080 m2 (Kernel density 50%). The population area (Kernel density 95%) of ecological park was 5,391 m2 and the core area (Kernel density 50%) was 736 m2. This study shows that it is appropriate to construct the area of alternative habitat for P. chosenicus at least 1.33 ha, and it is more advantageous for the ecological park to be constructed than the paddy field with high development pressure and human interference. If the rice paddies were to be abandoned for several years, or to be used traditional farming methods, such as refraining from using agricultural machinery and chemicals, they could be used as alternative habitat for P. chosenicus.

Effect of Electrolyzed Water Combined with Ultrasound and Organic Acids to Reduce Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus on Perilla Leaves (유기산 및 초음파 병용처리된 전해수를 이용한 들깻잎 중 Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus의 저감효과)

  • Kim, Se-Ri;Oh, Ki-Won;Lee, Myoung-Hee;Jung, Chan-Sik;Lee, Seo-Hyun;Park, Sun-Ja;Park, Jung-Hyun;Ryu, Kyoung-Yul;Kim, Byung-Seok;Kim, Doo-Ho;Yun, Jong-Chul;Chung, Duck-Hwa
    • Journal of Food Hygiene and Safety
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    • v.27 no.3
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    • pp.264-270
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    • 2012
  • This study was performed to compared the effectiveness of individual treatments (electrolyzed water: EW, organic acid, and ultrasound) and their combination on reducing foodborne pathogens from perilla leaves. Perilla leaves were innoculated with a cocktail of Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus. Inoculated perilla leaves were treated with EW combined with different concentration of acetic acid (0.5%, 1.0%, 1.5%, 2.0%) for 1 min at room temperature. Treatment of 3 pathogens on perilla leaves with electrolyzed water combined with ultrasound (25 kHz) and 0.5% acetic acid was also performed for 1 min. While the numbers of S. Typhimurium and B. cereus showed reduced with increasing acetic acid concentration, there is no difference in the number of S. aureus treated with EW containing 0.5% to 1.5% acetic acid. Discoloration was observed the perilla leaves treated with EW combined with more than 1.0% acetic acid. For all three pathogens, the combined treatment of EW and ultrasound resulted in additional 0.42 to 0.72 $log_{10}$ CFU/g. The maxium reductions of S. Typhimurium and B. cereus were 0.95, 1.23 $log_{10}$ CFU/g after treatment with EW combined with 0.5% acetic acid and ultrasound simultaneously. The results suggest that the treatment of EW combined with 0.5% acetic acid and ultrasound increased pathogens reduction compared to individual treatment.

Clinical Characteristics and Treatment Results of Neuroendocrine Carcinoma of Uterine Cervix (자궁경부 신경내분비암의 임상적 특징과 치료 결과)

  • Kim, Ok-Bae;Kim, Jin-Hee;Cha, Soon-Do;Choi, Tae-Jin;Ye, Ji-Won
    • Radiation Oncology Journal
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    • v.22 no.2
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    • pp.124-129
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    • 2004
  • Purpose : To evaluate the clinical findings, prognosis and treatment strategy of patients with neuroendocrine carcinoma of cervix. Materials and Methods: Thirteen patients with neuroendocrine carcinoma of cervix were included in this study, as confirmed histologically and immunohistochemically at the Dongsan Medical Center, Keimyung University, between May 1944 and October 2001. The mean age of patients was 56 years with a range of 32 to 78 years of age. According to the FIGO staging system, there were 5 patients with stage IB carcinoma, 5 patients with IIA, and 3 patients with stage IIB. Four patients underwent radical hysterectomy with pelvic lymphadenectomy, 3 of these patients also received postoperative radiotherapy, and one patient underwent extrafascial hysterectomy after radiotherapy. Primary radiotherapy was done in 9 patients, and 3 were irradiated postoperatively. Nine patients received chemotherapy, 7 received neoadjuvant and 2 received concurrent chemoradiotherapy. The radical purpose of radiotherapy consisted of external irradiation to the whole pelvis (4,500 $\~$5,400 cGy) and intracavitary irradiation (3,000 $\~$ 3,500 cGy). Results : The mean follow up duration was 36 months with a range of 3 to 104 months. The overall 5-year survival rate was 61.5$\%$ and the 5-year survival rates for stage IB, IIA, IIB were 60.0$\%$, 60.0$\%$, and 66.7$\%$ respectively (p=0.99). Eight patients are still alive without disease, and all of the 5 patients with recurrence are dead due to distant metastasis. Conclusion : Neuroendocrine carcinoma of cervix is highly aggressive, with early lymphatic dissemination and a high rate of distant recurrence. Therefore, an aggressive therapeutic strategy Is required to obtain pelvic and distant disease control. Multimodal therapy should be considered at the time of Initial diagnosis.

Study on the Structural and Transporting Property of Sr2Ru1-xCuxO4-y(0.0≤x≤0.5) (Sr2Ru1-xCuxO4-y(0.0≤x≤0.5) 화합물의 구조 및 전달 특성에 대한 연구)

  • Park, Jung-Chul
    • Journal of the Korean Chemical Society
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    • v.47 no.6
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    • pp.614-618
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    • 2003
  • $Sr_2Ru_{1-x}Cu_xO_{4-y}(0.0{\le}x{\le}0.5)$ compounds were prepared using a conventional solid state reaction. Based on the Rietveld refinements of X-ray diffraction results, it is revealed that $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds are the single phases with K2NiF4 type tetragonal system in the range of 0=x=0.3, while the mixed phases of$Sr_2RuO_4$ and $Sr_2CuO_3$ in the range of $0.4{\le}x{\le}0.5$. By means of X-ray photoelectron spectroscopy, the valence states of Ru and Cu in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, have been confirmed to 4+ and 2+, respectively. The bond length difference between $Ru-O_1 ({\times}4)\;and\;Ru-O_2 ({\times}2)\;in\;RuO_6$ octahedron is gradually decreased with increasing Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, which results in the lower c/a ratio. So, it might be assured that the variation of local symmetry of $RuO_6$ octahedron is very closely related to the transporting property of $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds. The behavior of resistivity discloses that the metallic property in $Sr_2RuO_4$ changes into the semiconducting one in proportion to the Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$.

Quality Characteristics of Functional Health Sunsik for Diabetes Mellitus (당뇨병환자를 위한 기능성 건강선식의 품질특성)

  • Kim Jun-Han;Park Pil-Sook;Moon Hye-Kyung;Lee Won-Young;Kim Jong-Kuk
    • Food Science and Preservation
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    • v.11 no.4
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    • pp.557-564
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    • 2004
  • This study was conducted to investigate the quality characteristics of functional health sunsik for diabetes mellitus. Nutrient compositions of commercial sunsik was consist of carbohydrate by grains, but sunsik for diabetes mellitus was lower carbohydrate content ratio and higher protein content ratio($19.35\%$), respectively. The sucrose content was highest in free sugars of sunsik, Oganic acids in sunsik were composed of malic acid, tartaric acid, oxalic acid and citric acid. Free amino acids of diabetes mellitus sunsik were predominantly contented 154.32 mg/100g of serine, 151.87 mg/100g of alanine and 100.00 mg/100g of glutamic acid, respectively. Main fatty acid, linoleic acid content was high $39.48\%$ in diabetes mellitus sunsik. Minerals like Ca, Mg, K, Na and Fe were found to contained in sunsik. The minerals contained most in diabetes mellitus sunsik were 332.25 mg/100g of Ca, 246.73 mg/100g of Mg, 219.95 mg/100g of K, 203.26 mg/100g of Na and 9.39 mg/100g of Fe. Total phenolics content of diabetes mellitus sunsik was high contained 436.10 mg/100g. Antioxidant activity(Electron Donating Ability($\%$)) was lower $26.75\%$ in diabetes mellitus sunsik than $70.57\%$ in a-tocopherol(400 ppm). Sensory evaluation score of in diabetes mellitus sunsik was high in cooked taste(3.4) and overall acceptance(3.4).

The Anti-angiogenic Potential of a Phellodendron amurense Hot Water Extract in Vitro and ex Vivo (in Vitro와 ex vivo에서 황백 온수추출물의 신생혈관 억제효과)

  • Kim, Eok-Cheon;Kim, Seo Ho;Bae, Kiho;Kim, Han Sung;Gelinsky, Michael;Kim, Tack-Joong
    • Journal of Life Science
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    • v.25 no.6
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    • pp.693-702
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    • 2015
  • Blocking new blood-vessel formation (angiogenesis) is now recognized as a useful approach to the therapeutic treatment of many solid tumors. The best validated approach to date is to target the vascular endothelial growth-factor (VEGF) pathway, a key regulator of angiogenesis. Many natural products and extracts that contain a variety of chemopreventive compounds have been shown to suppress the development of malignancies through their anti-angiogenic properties. Phellodendron amurense, which is widely used in Korean traditional medicine, has been shown to possess antitumor, antimicrobial, and anti-inflammatory properties, among others. The present study investigated the effects of P. amurense hot-water extract (PAHWE) on angiogenesis, a key process in tumor growth, invasion, and metastasis. To investigate PAHWE’s anti-angiogenic properties, this study’s authors performed an analysis of angiogenesis and endothelial-cell proliferation, migration, invasion, and tube formation, as well as zymogram assays and the rat aortic ring-sprouting assay. PAHWE inhibited cell growth, mobility, and vessel formation in response to VEGF in vitro and ex vivo. Furthermore, it reduced VEGF-induced intracellular signaling events, such as the activation of matrix metalloproteinases (MMPs) -2 and -9. These results indicate that PAHWE’s anti-angiogenic properties might lead to the development of potential drugs for treating angiogenesis-associated diseases such as cancer.