• Title/Summary/Keyword: 수영 활동

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Application of the QUAL2E Model and Risk Assessment for Water Quality Management in Namyang Stream in Hwaong Polder (화옹유역 남양천의 수질관리를 위한 QUAL2E적용과 위해성 평가)

  • Jang, Jae-Ho;Jung, Kwang-Wook;Kim, Hyung-Chul;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.39 no.1 s.115
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    • pp.110-118
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    • 2006
  • The Namyang Stream in Hwaong polder was planned for several water uses including recreation, where people can contact the water and consume some amount during the recreational activity. A human health risk was assessed from exposure to E. coli in the Namyang Stream, which receives partially treated wastewater from watershed. The QUAL2E model was applied to simulate stream water quality, and this model was calibrated and verified with field monitoring data. The calibration result showed a high correlation coefficient of greater than 0.9. The mean concentration of E. coli in the Namyang Stream from the QUAL2E output was in the range of 5,000 ${\sim}$ 8,000 MPN 100 mL^{-1}$, which exceeded national and international guidelines. The Beta-Poisson was used to estimate the microbial risk of pathogens ingestion and the Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. The Microbial risk assessment showed that the risk ranged from 7.9 ${\times}\;10^{-6}\;to\;9.4\;{\times}10^{-6}$. Based on USEPA guidelines, the range of $10^{-6}\;to\;10^{-8}$ was considered reasonable levels of risk for communicable disease transmission from environmental exposure, and the risk above $10^{-4}$ was considered to be in the danger of infection. Therefore, water quality of the Namyang Stream might not be in the danger of infection although it exceeded national and international guidelines. However, it was in the range of communicable disease transmission, and thorough wastewater collection and treatment at the source is recommended to secure safe recreation water quality.

Classification System of Wetland Ecosystem and Its Application (습지생태계 분류체계의 검토 및 적용방안 연구)

  • Chun, Seung Hoon;Lee, Byung Hee;Lee, Sang Don;Lee, Yong Tae
    • Journal of Wetlands Research
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    • v.6 no.3
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    • pp.55-70
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    • 2004
  • The wetland ecosystem is a complex products of various erosion force, accumulation as water flows, hydrogeomorphic units, seasonal changes, the amount of rainfalls, and other essential element. There is no single, correct, ecologically sound definition for wetlands because of the diversity of wetlands and the demarcation between dry and wet environments occurs along a continuum, but wetland plays various ecosystem functions. Despite comprehensive integration through classification and impact factors there is still lacking in systematic management of wetlands. Classification system developed by the USFWS(1979) is hierarchical progresses from systems and subsystems at general levels to classes, subclasses, dominance types, and habitat modifiers. Systems and subsystems are delineated according to major physical attributes such as tidal flushing, ocean-derived salts, and the energy of flowing water or waves. Classes and subclasses describe the type of substrate and habitat or the physiognomy of the vegetation or faunal assemblage. Wetland classes are divided into physical types and biotic types. For the wise management of wetlands in Korea, this study was carried out to examine methodology of USFWS classification system and discuss its application for Korean wetland hydrogeomorphic units already known. Seven wetland types were chosen as study sites in Korea divided into some different types based on USFWS system. Three wetland types belonging to palustrine system showed no difference between Wangdungjae wetland and Mujechi wetland, but Youngnup of Mt. Daeam was different from the former two types at the level of dominant types. This fact means that setting of classification system for management of wetland is needed. Although we may never know much about the wetland resources that have been lost, there are opportunities to conserve the riches that remain. Extensive inventory of all wetland types and documentation of their ecosystem functions are vital. Unique and vulnerable examples in particular need to be identified and protected. Furthermore, a framework with which to demonstrate wetland characteristics and relationships is needed that is sufficiently detailed to achieve the identification of the integrity and salient features of an enormous range of wetland types.

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Neural Bases of Empathy in Competitive vs. non-Competitive situation (경쟁과 비경쟁 상황에서 공감의 신경학적 기제)

  • Hwang, Su-Young;Yoon, Mi-Sun
    • Korean Journal of Cognitive Science
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    • v.27 no.3
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    • pp.441-467
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    • 2016
  • This fMRI study is aim to investigate effects of competitive environment in cognitive empathic process in human brain. Empathy is known as a crucial factor for human's adaptive behavior in aspects of social cognition and it is almost automatic process, on the other hand competitive situation is psychologically devastated environment to win someone for getting rewards. We hypnotized that reading and understanding of other person's mind are a specific characteristic related to survival evolutionarily, however competition would have an effect on the empathic cognitive process because of mechanisms of competition. To manipulate the competitive atmosphere, one researcher took a role of competitor against participants and they were instructed to get monetary rewards when their performance was better than a competitor. 21 participants(9 males and 12 females) performed to judge the emotional valence of the empathic task consisted of illustrated images with various situation could be experienced in real world as on $1^{st}$ person perspective in both competitive and non-competitive condition, and did same performance with objects stimulus in control condition. In order to examine the competition effects on empathic process,, hemodynamic response were obtained during fMRI session and the imaging data were analyzed to identify brain regions where responses to each condition across the two consecutive runs. Participants' reaction time in competitive condition was faster statistically significant than non-competitive one. Activation for competitive condition increased in the following areas: ACC, mPFC, SMG, thalamus extended caudate and Nacc, parahippocampal gyrus, and for non-competitive condition increased paracingulate gyrus, temporal pole, vmPFC, superior occipital gyrus. As a result of regression analysis using empathic scores as covariance, the rSMG, IFG, fusiform gyrus, thalamus, putamen were correlated with higher empathic levels, and TPJ were correlated with lower empathic scores. We suggest that these observations could mean competitive environment have an effect on neural base of cognitive empathic process.

Effect of Fermented Cirsium japonicum Extract on Testosterone Deficiency Syndrome (엉겅퀴 발효 추출물을 통한 남성 갱년기 증상 개선 효과)

  • Jeong, Byung Seo;Kim, Seong Hoon;Kim, Hyun Pyo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.7
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    • pp.790-800
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    • 2017
  • As men get older, total testosterone levels decline gradually, and concentrations of free and bioavailable testosterone decline sharply with each decade beyond their 30s. Andropause or testosterone deficiency syndrome (TDS) is defined as a decrease in sexual satisfaction or decline in general well-being accompanied by low levels of testosterone in older men. This male climacteric is characterized by nervousness, reduced potency, decreased libido, irritability, fatigue, depression, memory problems, sleep disturbances, and hot flushes. Cirsium japonicum (CJ) is used as a traditional medicine for hemorrhage, blood congestion, and inflammation in Korea. However, there is no report on the efficacy of CJ treatment for TDS. In this study, we observed the mitigating effect of CJ extract (CE) and fermented CJ extract (FCE) on symptoms of TDS. In elderly male rats, total and testosterone levels, hind limbs muscles, forced swimming time, and total and motile sperm counts significantly increased after daily intake of CE and FCE for 6 weeks. In contrast, sex hormone binding globulin, retroperitoneal fat, total serum cholesterol, and triglyceride levels were significantly reduced in CE and FCE groups. However, there was no difference in prostate specific antigen, aspartate aminotransferase, and alanine aminotransferase levels among all groups, which means CE and FCE did not have putative adverse effects. In a cell experiment, we also observed that CE and FCE enhanced expression of genes related to testosterone biosynthesis but reduced genes involved in testosterone conversion. On the whole, these positive effects on TDS were greater in FCE compared to CE. Thus, these results suggest the potential of FCE as a promising natural product for recovering testosterone levels and alleviating TDS.

Development of Water-Resistant O/W Emulsion-Typed Sunscreening Cosmetics through Triblock Polymeric Surfactant-Mediated Re-emulsification Inhibition (삼중블록 고분자 계면활성제의 재유화 억제 기능을 이용한 지속내수성 O/W 에멀젼형 자외선 차단용 화장품 개발)

  • Lee, Ji Hyun;Hong, Sung Yun;Lee, Jin Yong;An, So Youn;Lee, Hyo Jin;Kim, Sung Yong;Lee, Jun Bae;Kim, Jin Woong;Shin, Kyounghee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.2
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    • pp.199-208
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    • 2019
  • This study reports water-resistant oil-in-water (O/W) emulsion-based sunscreening formulations prepared using a poly(ethylene glycol)-poly(${\varepsilon}$-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG) triblock polymeric surfactant. As a result of a variety of outdoor recreational activities such as swimming and hiking, consumer needs for development of advanced water-resistant sunscreen formulations are increasing. Water-resistant sunscreens are mostly based on water-in-oil (W/O) emulsions, because they should not be wiped off by water or sweat. However, the W/O emulsion formulations have a disadvantage in that the feeling of use is oily and difficult to remove. On the other hand, the O/W emulsion formulations are excellent in achieving the better skin feel as well as the easier removal. However, it is difficult to provide the O/W emulsion formulations with the water-repelling performance, since re-emulsification likely occurs upon getting touch with water. To solve this problem, this study proposes a O/W emulsion-based sunscreen formulation, a triblock polymeric surfactant having relatively high interfacial tension HLB value (~ 10). This allows the sunscreen formulations to exhibit the improved water repellence function by preventing their re-emulsification. The sunscreen formation system prepared in this study would be useful for diversification of functional sunscreen products, taking advantages of its excellent emulsion stability, UV protection performance, long lasting water-resistant function and selective cleansing effect with only foam cleanser.

Floristic features of upland fields in South Korea (우리나라 밭 경작지에 출현하는 식물상 특성)

  • Kim, Myung-Hyun;Eo, Jinu;Kim, Min-Kyeong;Oh, Young-Ju
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.528-553
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    • 2020
  • Upland fields are characterized by dry environments, a high degree of disturbance by farming practices such as double-cropping, and a high diversity of crops compared to other field types. This study focused on the floristic composition and characteristics of upland fields in South Korea. Flora surveys were conducted in 36 areas in nine provinces at two times (June and August) in 2015. The results showed that the vascular plants in the upland fields in South Korea included 532 taxa, containing 100 families, 322 genera, 483 species, nine subspecies, 37 varieties, one form, and two hybrids. Among the 100 families, Asteraceae was the most diverse in species (75 taxa), followed by Poaceae (68 taxa), Fabaceae (34 taxa), Polygonaceae (21 taxa), Rosaceae (19 taxa), and Liliaceae (17 taxa). Based on the occurrence frequency of each species, Acalypha australis L. (100%), and Artemisia indica Willd. (100%) were the highest, followed by Humulus scandens (Lour.) Merr., Rorippa palustris (L.) Besser, Conyza canadensis (L.) Cronquist, Erigeron annuus (L.) Pers., Lactuca indica L., Commelina communis L., Digitaria ciliaris (Retz.) Koeler, Echinochloa crus-galli(L.) P.Beauv., Cyperus microiria Steud., and Oxalis corniculata L. The biological type of upland fields in South Korea was determined to be Th-R5-D4-e type. Rare plants were found in 11 taxa: Taxus cuspidata Siebold & Zucc, Magnolia kobus DC, Clematis trichotoma Nakai, Aristolochina contorta Bunge, Buxus sinica (Rehder & E.H.Wilson) M.Cheng var. koreana (Nakai ex Rehder) Q.L.Wang, Melothria japonica (Thunb.) Maxim, Mitrasacme indica Wight, Lithospermum arvense L., Carpesium rosulatum Miq., Allium senescens L., and Pseudoraphis sordida (Thwaites) S.M.Phillips & S.L.Chen. Ninety-seven taxa contained naturalized plants composed of 24 families, 68 genera, 97 species, one variety, and one form. The urbanization and naturalization indices were 30.5% and 18.4%, respectively.