• Title/Summary/Keyword: P2P Sites

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Pollution Characteristics of Plastic Debris on the Gwanganri Beach, Busan (부산 광안리 해수욕장에서 표착된 플라스틱 폐기물의 오염 특성)

  • KIM, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.6
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    • pp.1854-1864
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    • 2015
  • In order to analyze the pollution characteristics of small plastic debris(SPD) ashore on the shoreline of coastal flow, 12 times of survey were conducted on the Gwanganri beach of Busan for nearly 3 years. The sampled stations on the beach were divided into 11 squared survey sites from St. G1 to G11(see [Fig. 1]) and all of SPD was sorted into 11 items like P1 to P11 according to the kind of plastic materials and products(see

    ). 1. Total weights of them were widely ranged from 3.23g to 30.58g and also total amounts, from 39 ea to 398 ea on each site. 2. The ratio of items, P2 and P3, were accounted for 63% among all of them. 3. The seasonal variabilities of them were not founded with remarkable. 4. The correlation of total weights and amounts have reliable coefficients to some extent on the survey sites, but nearly didn't have reliances on items. 5. The average densities of total weights and amounts were computed with $4.506g/m^2$, $51.936ea/m^2$, respectively.

  • Investigation of the groundwater contamination around landfill where slaughtered animals were buried

    • Bark, Jun-Jo;Jung, Hae-Sun;Woo, Jong-Tae;Lee, Sung-Sik
      • Korean Journal of Veterinary Service
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      • v.29 no.4
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      • pp.459-467
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      • 2006
    • This study was designed to investigate if there were groundwater contamination in 17 landfill where slaughtered animals were buried during the crisis of 2002 foot-and-mouth-disease (FMD) outbreaks in Gyeonggi province. From March to August 2005 groundwater was collected once a month from 17 sites, and examined with potential for hydrogen (pH), colour, turbidity, lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), copper (Cu), zinc (Zn) , iron (Fe), manganese (Mn) , aluminium (Al), nitrate-nitrogen $(NO_3-N)$, ammonia-nitrogen $(NH_3-N)$, microbial pathogen and Escherichia spp. In the examination of $NH_3-N$ which of the mean concentration was from not-detected (ND) to 0.05 mg/l. The range of $NH_3-N$ level was $0.3-24.1mg/{\ell}$. However, groundwater from four sites was to go beyond the drinking water quality standard (DWQS), i.e., the mean concentration of those were $15.5mg/{\ell}\;(site\;1),\;20.7mg/{\ell}\;(site\;9),\;24.1mg/{\ell}\;(site\;13)\;and\;10.6mg/{\ell}\;(site\;17)$. In the investigation of pH, colour and turbidity, all of the pH were below of DWQS (pH 5.8-6.6), but one site in color test and four sites in turbidity test were over the standard level. Among 9 metal ions examined, Mn was in excess of DWQS, and its concentration was $2.4mg/{\ell}$. Pb, Cd, Hg and As were not traced. The contents of Cu, Zn, Fe and Al were $ND-0.22mg/{\ell},\;0.01-0.05mg/{\ell},\;ND-0.05mg/{\ell}\;and\;0.03-0.16mg/{\ell}$, respectively. Escherichiae spp were not identified, but bacterial colonies were detected at 3 groundwater including 2 sites over the DWQS at the level of $491CFU/m{\ell}\;(site\;4)\;and\;217CFU/m{\ell}\;(site\;15)$.

    Allelic Diversity of MSP1 Gene in Plasmodium falciparum from Rural and Urban Areas of Gabon

    • Mawili-Mboumba, Denise Patricia;Mbondoukwe, Noe;Adande, Elvire;Bouyou-Akotet, Marielle Karine
      • Parasites, Hosts and Diseases
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      • v.53 no.4
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      • pp.413-419
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      • 2015
    • The present study determined and compared the genetic diversity of Plasmodium falciparum strains infecting children living in 2 areas from Gabon with different malaria endemicity. Blood samples were collected from febrile children from 2008 to 2009 in 2 health centres from rural (Oyem) and urban (Owendo) areas. Genetic diversity was determined in P. falciparum isolates by analyzing the merozoite surface protein-1 (msp1) gene polymorphism using nested-PCR. Overall, 168 children with mild falciparum malaria were included. K1, Ro33, and Mad20 alleles were found in 110 (65.5%), 94 (55.9%), and 35 (20.8%) isolates, respectively, without difference according to the site (P>0.05). Allelic families' frequencies were comparable between children less than 5 years old from the 2 sites; while among the older children the proportions of Ro33 and Mad20 alleles were 1.7 to 2.0 fold higher at Oyem. Thirty-three different alleles were detected, 16 (48.5%) were common to both sites, and 10 out of the 17 specific alleles were found at Oyem. Furthermore, multiple infection carriers were frequent at Oyem (57.7% vs 42.2% at Owendo; P=0.04) where the complexity of infection was of 1.88 (${\pm}0.95$) higher compared to that found at Owendo ($1.55{\pm}0.75$). Extended genetic diversity of P. falciparum strains infecting Gabonese symptomatic children and high multiplicity of infections were observed in rural area. Alleles common to the 2 sites were frequent; the site-specific alleles predominated in the rural area. Such distribution of the alleles should be taken into accounts when designing MSP1 or MSP2 malaria vaccine.

    Metallurgical Study of Iron Artifacts from Guryong-ri Site in Ungcheon, Boryeong

    • Choi, Eun Young;Cho, Nam Chul
      • Journal of Conservation Science
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      • v.38 no.4
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      • pp.289-300
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      • 2022
    • In the 6th and 7th centuries, 5 iron artifacts excavated form the Baekje Stone Tomb in Guryong-ri site, Ungcheon, Boryeong, were studied. The sample were metal microscopic observation, SEM-EDS analysis and Raman micro-spectroscopy analysis were conducted to understand the metallurgical characteristics. The microstructure observation showed the presence of ferrite and pearlite throughout, and differences in carbon content existed depending on the direction. Non-metallic inclusions were in the form of long lines, and most of them were wüstite, fayalite. It is indicated that the artifacts were forge welded using hypoeutectoid steel, with signs of carburizing and decarburizing processes. Some crystals with high P2O5, TiO2, CaO content were identified as sarcopside, ulvöspinel, and perovskite, respectively, through Raman spectroscopy. A comparison of the results with previous studies on the sites of Bujang-ri site in Seosan and Bongseon-ri site in Seocheon, which are adjacent sites in the coastal area, revealed that, while heat treatment technology was available, the artifacts were not heat-treated considering the purpose for use for these artifacts. The chemical composition of the non-metallic inclusions P2O5, TiO2, CaO were plotted in proportions to SiO2 and compared with adjacent sites. Considering that the P2O5/SiO2 ratio was widely distributed, the refining technology was not uniform. In addition, the TiO2/SiO2 ratio was found to be higher than that of other sites, meaning that a titanium-containing ore was used to manufacture the artifacts, unlike in surrounding sites, but it is not detected in all artifacts, so it may have been affected by various factors such as furnace walls in addition to raw materials. Although slag formers were used, considering the CaO/SiO2 ratio and the (Al2O3/SiO2)/(CaO/SiO2) ratio, which appear to be similar to the surrounding sites, but it is possible that CaO containing raw ore was used because it is also affected by the components of raw ore. As a result of the study, it is highly likely that ore different from that of the surrounding sites was used for production, but a more comprehensive comparative study with the surrounding sites is needed in the future.

    Incidence and Risk Factors for Surgical Glove Perforation (수술용 장갑의 천공률에 대한 연구)

    • Yoo, Seon Ju;Lim, Young Shin;Kim, Myung Suk
      • Journal of Korean Clinical Nursing Research
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      • v.16 no.3
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      • pp.63-71
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      • 2010
    • Purpose: This study was conducted to evaluate the incidence and risk factors for surgical glove perforation during operation. Methods: During the month of december 2008, a total of 1,400 pairs of surgical gloves used in major operations was collected in a tertiary hospital. All gloves were examined immediately after operation using the standardized water-leak method to detect any perforation. Incidence of the glove perforation was counted according to the type of operation, operation time, the number of involved personnel, perforation sites, and the manufacturing companies. Results: Out of 2,800 gloves examined, 312 perforations were detected comprising 11.1% of samples. In terms of the type of operation, the perforation incidence varied from 5% to 20%, and the perforation rates in CS (20%) and NS (18%) (p<.001) were significantly higher than those in other departments. The 1st assistant or scrub nurse got glove perforation more frequently than the 2nd assistant or operator (p<.001). Longer operation time was associated with higher incidence of perforation evidently (p<.001). In terms of the sites, the thumb and index finger were more frequently perforated than other sites (4.1% and 3.4% respectively) without any differences between left and right side. Conclusion: Risk factors for glove perforation including the department of operation, operation time, participating personnel, and location of perforation should be taken into account to improve surgical safety.

    Simultaneous Refinement of Primary and Eutectic Si in Hypereutectic Al-Si Alloys (과공정 Al-Si합금에서의 초정 및 공정 Si의 동시 미세화)

    • Park, Jae-Young;Lee, Jae-Sang;Ra, Hyung-Yong
      • Journal of Korea Foundry Society
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      • v.15 no.3
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      • pp.262-271
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      • 1995
    • It is well known what is impossible to refine primary and eutectic Si simultaneously by addition of both Cu-P and Sr(or Na). Because of the formation of compound $Sr_3P_2(or Na_3P)$ in the melt, in the result, both effects disappear. In this study Al-Cu-P alloy that comprises AlP compounds inside is added in the melt with Sr simultaneously. As AlP compounds that act on nucleation sites of primary Si are not formed but added directly an the melt, it is difficult to form $Sr_3P_2$ by reaction with Sr. Therefore it is possible to refine primary and eutectic Si simultaneously in the general casting process by use of Al-Cu-P alloy and Sr.

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    Ionic Conductivity of $Li_2O-B_2O_3-P_2O_5$ based Glasses ($Li_2O-B_2O_3-P_2O_5$계 유리의 이온전도성)

    • 박강석;강은태
      • Journal of the Korean Ceramic Society
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      • v.30 no.5
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      • pp.373-380
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      • 1993
    • Li2O-B2O3-P2O5 glasses with high lithium content were analysed by electrical characterization. The electrical conductivity increase with Li content and exhibits a maximum value of 1.2$\times$10-4S/cm near B2O3/P2O5=1 at 15$0^{\circ}C$. Glass transitiion temperature increased with conductivity. Concentration of charge carrier and distribution of relaxation time were independent of temperature. In this system the variation of conductivity with the composition was depend on mobility of lithium ion. Basically, it is attribute to primitive activation energy. Enhancement of conductivities was related to be formation of (B-O-P)-, di-, and metaborate group, which give additional available sites for Li+ diffusion.

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    Purification and the Catalytic Site Residues of Pseudonomas fragil Lipase Expressed in Escherichia coli

    • Kim, Tae Ryeon;Yang, Cheol Hak
      • Bulletin of the Korean Chemical Society
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      • v.16 no.5
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      • pp.401-406
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      • 1995
    • The P. fragi lipase overexpressed in E. coli as a fusion protein of 57 kilodalton (kDa) has been purified through glutathione-agarose affinity chromatography by elution with free glutathione. The general properties of the purified GST-fusion protein were characterized by observing absorbance of released p-nitrophenoxide at 400 nm which was hydrolyzed from the substrate p-nitrophenyl palmitate. The optimum condition was observed at 25 $^{\circ}C$, pH 7.8 with 0.4 ${\mu}g$ of protein and 1.0 mM substrate in 0.6% (v/v) TritonX-100 solution. Also the lipase was activated by Ca+2, Mg+2, Ba+2 and Na+ but it was inhibited by Co+2 and Ni+2. pGEX-2T containing P. fragi lipase gene as expression vector was named pGL191 and used as a template for the site-directed mutagenesis by sequential PCR steps. A Ser-His-Asp catalytic triad similar to that present in serine proteases may be present in Pseudomonas lipase. Therefore, the PCR fragments replacing Asp217 to Arg and His260 to Arg were synthesized, and substituted for original fragment in pGL19. The ligated products were transformed into E. coli NM522, and pGEX-2T harboring mutant lipase genes were screened through digestion with XbaI and StuI sites created by mutagenic primers, respectively. No activity of mutant lipases was observed on the plate containing tributyrin. The purified mutant lipases were not activated on the substrate and affected at pH variation. These results demonstrate that Asp217 and His260 are involved in the catalytic site of Pseudomonas lipase.

    Benthic algal community of Ulleungdo, East coast of Korea (동해안 울릉도 해역의 해조군집)

    • KIM, Sung-Tae;HWANG, Kangseok;PARK, Gyu-Jin;CHOI, Chang Geun
      • Journal of Fisheries and Marine Sciences Education
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      • v.28 no.1
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      • pp.83-90
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      • 2016
    • A subtidal marine benthic algal vegetation at Ulleungdo Island, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method at seven stations in May and August 2014. The total number of marine algal species was 148 species composed of the green algae of 12 species, the brown algae of 40 species and the red algae of 96 species. Mean biomass in dry weight was $94.8g\;dry\;weight\;m^{-2}$ in study sites, $98.1g\;dry\;weight\;m^{-2}$ in upper tidal level, and $86.6g\;dry\;weight\;m^{-2}$ in middle level. The R/P and (R+C)/P value reflecting flora characteristic were 1.9 and 2.3, respectively. Three groups produced by cluster analysis, one including sites Neunggeol, Daepung, Jukdo, second including sites Gongam, Ssangjeongcho and the other including sites Gwaneum, Hangnam, showed meaningful difference in similarity (about 40%), each other. The number of marine algal species and biomass in Ulleungdo Island area were markedly reduced comparing that in the previous studies. This result may suggest probably change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

    Analysis of the relationship between e-brand personalities and visual attributes (웹페이지 디자인의 이브랜드 개성 구축을 위한 시각조형특성 분석)

    • Park Su-E
      • Archives of design research
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      • v.19 no.4 s.66
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      • pp.187-204
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      • 2006
    • The brand personality of online products and services is know as its e-brand personality. Although, in the competitive conditions of online markets, e-brand personality is agreed to be an important factor, few studies have suggested how to establish e-brand personality through the visual design of web sites. This study identifies and verifies causal relationships between the visual attributes of web pages and e-brand personalities. The first identifies four major dimensions of e-brand personality on diverse web sites. The second uses 52 experimental home pages to identify key visual attributes associated with those four personality dimensions. The third is a confirmatory study with 16 experimental web sites that verifies causal relationships between visual attributes and e-brand personalities. The results show that two visual attributes, 'simplicity' and 'cohesion,' help to establish a 'bold' personality. Three attributes, 'contrast,' 'density,' and 'regularity,' affect whether a site has an 'analytical' personality. 'Contrast,' 'cohesion,' 'density,' and 'regularity' all influence whether a web site is perceived to have a 'friendly' personality. 'Regularity' and 'balance' were expected to affect the 'sophisticated' personality dimension, but no such impact was observed. The paper concludes with a discussion of implications, limitations, and future research directions.

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