• 제목/요약/키워드: Natural sources

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장거리 수송 연무 발생과 연관된 우리나라 대도시 대기질 특성 (Characteristics of Air Quality over Korean Urban Area due to the Long-range Transport Haze Events)

  • 조현영;김철희
    • 한국대기환경학회지
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    • 제27권1호
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    • pp.73-86
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    • 2011
  • Haze phenomena were analyzed to assess the impact of long range transport process on the air quality of Seoul and Busan. We statistically classified haze days observed in both Seoul and Busan into two types of haze cases: stagnant case and long-range transport case, and analyzed the air pollutant levels comparatively for each of the two cases for the period of 2000~2007. The results showed that the long-range transport haze case occurs less frequently with the occurrence frequency of 35.5% than stagnant case with the occurrence frequency of 64.5%. During the observed all haze days, all pollutants have high concentration in comparison with those under other meteorological conditions (Rain, Mist, Dust, Clear, Rain+Mist) except for only $PM_{10}$ of Dust case where its level shows highest among total 6 categorized conditions. The long range transport haze case shows similar levels of $PM_{10}$ and $NO_2$, but higher $SO_2$ and lower $O_3$ compared with stagnant haze cases, suggesting the importance of sulfur chemistry for long range transport haze case and local photochemistry for stagnant haze case. In addition, by employing the NOAA/HYSPLIT-4 backward trajectory model, we subdivided the long range transport haze cases into two different sources: urban anthropogenic high emission areas of central China, and natural emission sources over north China and/or Mongolia. The former long range transport haze case shows higher occurrence (with Seoul 70% and Busan 85%) than the latter haze case (with Seoul 30% and Busan <10%). This is also implying that the long haze phenomena occurred over Korea have been influenced by not only the anthropogenic emissions but also the natural dust emissions. These both emission sources can be good contributors in calculating the source-receptor relationship over Korean atmospheric environment.

자연형 도로 비점오염저감시설의 저감효율 및 적용성 연구 (A Study on Removal Efficiency and Applicability of Natural Type Road Non-point Pollutant Reduction Facilities)

  • 이상혁;조혜진;김이형
    • 한국도로학회논문집
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    • 제16권6호
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    • pp.9-17
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    • 2014
  • PURPOSES : The purpose of this study is to assess removal efficiency of non-point pollutants and applicability for non-point pollutant reduction facilities by conducting the demonstration project operation. METHODS : In order to analyze removal efficiency of non-point pollutants for facilities such as a grassed swale, a small constructed wetland, a free water surface wetland, a horizontal sub-surface flow wetland, and a sand filtration, the field data including specifications of facilities, rainfall, inflow and runoff rainfall effluent etc. was acquired after occurring rainfall events, and the acquired data was analyzed for removal efficiency rate to assess road non-point pollutants facilities using event mean concentration (EMC) and summation of load (SOL) methods. RESULTS : The results of analyzing rainfall effluent, non-point pollutant sources showed that total suspended solid (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), chrome (Cr), zinc (Zn), and lead (Pb) can be removed through non-point pollutant reduction facilities by 60.3% ~ 100%. Especially removal efficiency of TSS, COD and BOD is relatively higher than removal efficiency of other non-point pollutant sources in all kind of non-point pollutant facilities. CONCLUSIONS : Based on the result of this study, even though natural type of non-point pollutant reduction facilities for roads occupy small areas comparing with drainage basin areas, most of non-point pollutant sources would be removed through the facilities.

Meta-analysis on Methane Mitigating Properties of Saponin-rich Sources in the Rumen: Influence of Addition Levels and Plant Sources

  • Jayanegara, Anuraga;Wina, Elizabeth;Takahashi, Junichi
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권10호
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    • pp.1426-1435
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    • 2014
  • Saponins have been considered as promising natural substances for mitigating methane emissions from ruminants. However, studies reported that addition of saponin-rich sources often arrived at contrasting results, i.e. either it decreased methane or it did not. The aim of the present study was to assess ruminal methane emissions through a meta-analytical approach of integrating related studies from published papers which described various levels of different saponin-rich sources being added to ruminant feed. A database was constructed from published literature reporting the addition of saponin-rich sources at various levels and then monitoring ruminal methane emissions in vitro. Accordingly, levels of saponin-rich source additions as well as different saponin sources were specified in the database. Apart from methane, other related rumen fermentation parameters were also included in the database, i.e. organic matter digestibility, gas production, pH, ammonia concentration, short-chain fatty acid profiles and protozoal count. A total of 23 studies comprised of 89 data points met the inclusion criteria. The data obtained were subsequently subjected to a statistical meta-analysis based on mixed model methodology. Accordingly, different studies were treated as random effects whereas levels of saponin-rich source additions or different saponin sources were considered as fixed effects. Model statistics used were p-value and root mean square error. Results showed that an addition of increasing levels of a saponin-rich source decreased methane emission per unit of substrate incubated as well as per unit of total gas produced (p<0.05). There was a decrease in acetate proportion (linear pattern; p<0.001) and an increase in propionate proportion (linear pattern; p<0.001) with increasing levels of saponin. Log protozoal count decreased (p<0.05) at higher saponin levels. Comparing between different saponin-rich sources, all saponin sources, i.e. quillaja, tea and yucca saponins produced less methane per unit of total gas than that of control (p<0.05). Although numerically the order of effectiveness of saponin-rich sources in mitigating methane was yucca>tea>quillaja, statistically they did not differ each other. It can be concluded that methane mitigating properties of saponins in the rumen are level- and source-dependent.

Beijing Natural Gas Supply and Environment Protection

  • Shaohua, Dong;Hong, Zhang
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 2008년도 춘계학술 발표회
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    • pp.41-60
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    • 2008
  • This paper analyses the main cause of pollution in Beijing city-the limiting of the pollution caused by coal burning has seen important progress, and natural gas is assuming an important role in China's energy strategy as the country actively seeks new and cleaner sources of energy, since 1997 to 2007, the gas supply for Beijing was given, compared with the air quality standard above II which set up by WHO(World Healthy Organization), as a result the important relationship between the environment and gas using was found, then the percent of $SO_2$, $NO_2$, PM10, CO, $O_3$ of air was shown from August $8^{th}-24^{th}$ 2006, Which it was verified that the quality of air will be perfect within the standard of WHO during the Olympic Game 2008 China.

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환경음에 대한 계층별 인식 차이에 관한 조사 연구 (The Study on Cognition Difference of Environmental Sounds due to Subject' Classes)

  • 신훈;백건종;송민정;장길수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.1187-1190
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    • 2007
  • This study aims to induce acoustic environmental characteristics which could be used for soundscape design by carrying out factor analysis on sound source image and cognition analysis on subjects' responses on selective questions due to class differences. The results of this study are as follows ; Satisfaction rate differences on exterior acoustic environment due to sensitivity and residence year were revealed. After factor analysis of living sound sources' image, it is known that natural sound, traditional sound, socials traffic sound, rural sound, religious sound and the others are main factors. Social traffic sound is the most one that should be eliminated and traditional sound is selected as a most Korean-like sound. Natural sound is evaluated as the most one that should be preserved and the most retrospectively one.

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부순모래와 천연모래 혼합사용이 콘크리트의 품질에 미치는 영향 (The Effect of Using Mixed Crushed Sand and Natural Sand in the Qualities of Concrete)

  • 류금성;고경택;박정준;김기훈;한천구;이장화
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.459-462
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    • 2005
  • Recently, interest grew on the quality of aggregates following the diminution of primary resources from river and the growing construction demand which exhausted high-quality sand sources around large cities and incited the use of low grade aggregates like shore sand and sea sand that can be supplied in natural state. Moreover, the most sensitive aspect highlighted by the unstability of aggregate supply is the quality. The extreme insufficiency of quality criteria about the materials currently used as substitute aggregates and about concrete mixed with such materials is also critical. This study investigated influence of qualities of concrete which is using mixed crushed sand and natural sand

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Synthetic approach to the generation of antibody diversity

  • Shim, Hyunbo
    • BMB Reports
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    • 제48권9호
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    • pp.489-494
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    • 2015
  • The in vitro antibody discovery technologies revolutionized the generation of target-specific antibodies that traditionally relied on the humoral response of immunized animals. An antibody library, a large collection of diverse, pre-constructed antibodies, can be rapidly screened using in vitro display technologies such as phage display. One of the keys to successful in vitro antibody discovery is the quality of the library diversity. Antibody diversity can be obtained either from natural B-cell sources or by the synthetic methods that combinatorially generate random nucleotide sequences. While the functionality of a natural antibody library depends largely upon the library size, various other factors can affect the quality of a synthetic antibody library, making the design and construction of synthetic antibody libraries complicated and challenging. In this review, we present various library designs and diversification methods for synthetic antibody library. From simple degenerate oligonucleotide synthesis to trinucleotide synthesis to physicochemically optimized library design, the synthetic approach is evolving beyond the simple emulation of natural antibodies, into a highly sophisticated method that is capable of producing high quality antibodies suitable for therapeutic, diagnostic, and other demanding applications. [BMB Reports 2015; 48(9): 489-494]

Development of Anti-viral Agents from Natural Sources

  • Hattori, Masao
    • Plant Resources
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    • 제4권3호
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    • pp.192-195
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    • 2001
  • Human immunodeficiency virus (HIV), the causative agent of AIDS, still continues to spread rapidly in the world population, especially in Africa and Southeast Asia. At present, two kinds of therapeutic approaches are used for treatment of AIDS. One is to target HIV reverse transcriptase, which is responsible for the viral genome transcription. The other is to inhibit HIV pretense PR, which is essential for the processing of viral proteins. Drug combinations based on these approaches can reduce the blood virus to an undetectable level. However, a small amount of virus may lurk inside the immune cells in a dormant state. Another major obstacle of long-term treatment of the disease is remarkable mutation in HIV. Most of the clinical chemotherapeutic agents have one or more of these problems. High cost and harmful side-effects further reduced the desirability of these drugs. In the course our studies on development of anti-HIV agents from natural products, we investigated various crude drugs for their inhibitory activity against HIV-induced cytopathic effects (CPE) in culture cells, HIV-pretense (PR), HIV-reverse transcriptase (RT) including ribonuclease H (RNase H), and HIV integrase (INT). In the present paper, some inhibitory substances relating to the development of anti-HIV agents are reported.

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Exogenous Natural Glycoprotein Multiple Mechanisms of Anti-tumor Activity

  • Yuan, Hong-Liang;Liu, Xiao-Lei;Dai, Qi-Chang;Song, Hui
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권4호
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    • pp.1331-1336
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    • 2015
  • Natural glycoproteins can induce apoptosis of tumor cells and exert anti-tumor activity by immunomodulatory functions, cytotoxic and anti-inflammation effects, and inhibition of endothelial growth factor. Given their prospects as novel agents, sources of natural antitumor glycoproteins have attracted attention and new research directions in glycoprotein biology are gradually shifting to the direction of cancer treatment and prevention of neoplastic disease. In this review, we summarize the latest findings with regard to the tumor suppressor signature of glycoproteins and underlying regulatory mechanisms.

A report of unrecorded bacterial species of Korea isolated in 2016, belonging to the family Deinococcaceae and Planctomycetaceae

  • Kim, Dong-Uk;Kim, Ju-Young;Cha, Chang-Jun;Kim, Wonyong;Kim, Myung Kyum
    • Journal of Species Research
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    • 제7권1호
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    • pp.9-12
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    • 2018
  • In 2016, as part of a larger effort to discover indigenous prokaryotic species in Korea, we isolated the family Deinococcaceae and Planctomycetaceae as unrecorded bacterial species. From the high 16S rRNA gene sequence similarity (>98.5%) and formation of a robust phylogenetic clade with known species, it was determined that each strain was a distinct bacterial species. There are no official reports that these two species have been described in Korea; therefore, the bacterial strains of Deinococcus and Blastopirellula are described for the first time in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.