• Title/Summary/Keyword: P2P Sites

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Influences of Forest Management Practices on pH and Electrical Conductivity in the Throughfall and Stemflow with the Abies holophylla and Pinus koraiensis Dominant Watershed (전나무림, 잣나무림 유역에서 수관통과우와 수간유하수의 수소이온농도 및 전기전도도에 미치는 산림시업의 영향)

  • Jeong, Yong-Ho;Kim, Kyong-Ha;Park, Jae-Hyeon
    • Korean Journal of Ecology and Environment
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    • v.35 no.1 s.97
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    • pp.52-61
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    • 2002
  • This research was conducted to evaluate the effect of forest management practices on pH and electrical conductivity to get fundamental information on water purification capacity after forest operation. Rainfall, throughfall and stemflow were sampled at the study sites which consist of Abies holophylla and Pinus koraiensis in Gwangreung Experimental Forest for S months from May to November 1999. Mean pH of the throughfall of the beginning of the event was higher in management (thinning and pruning) sites of Abies holophylla and Pinus koraiensis stands than nonmanagement site of Abies holophylla and Pinus koraiensis stands. In addition, pH of the throughfall of the total amount of the event showed similar trends which are higher pH in the management sites compared with the non- management sites. This result indicates that managements such as thinning and pruning improve tree butler capacity of rainfall pH. According to the linear regression results, pH of the throughfall of the total amount of the event in non-management sites = 0.735${\times}$pH of the throughfall of the beginning of the event in non-management sites+1.849 ($R^2\;=\;0.82$) and pH of the throughfall of the total amount of the event in management sites= 0.863${\times}$pH of the throughfall of the beginning of the event in management sites +1.0242 ($R^2\;=\;0.87$). In case of stemflow pH, pH of the sternflow of the total amount of the event in non-management sites = 0.53${\times}$pH of the stemflow of the beginning of the event in non- management sites+2.7709 ($R^2\;=\;0.64$) and pH of the stemflow of the total amount of the event in management sites = 0.5854${\times}$pH of the stemflow of the beginning of the event in management sites+2.7045 ($R^2\;=\;0.65$). Electrical conductivity (EC) of the throughfall of the beginning and total amount of the event was highest in non- management site in Abies holophylla, followed by management sites in fsies Abies holophylla, non-management site in Pinus koraiensis, and management sites in Pinus koraiensis stands, respectively. According to the linear regression results, EC of the throughfall of the total amount of the event in non-managementsites = 0.4045${\times}$EC of the throughfall of the beginning of the event in non-management sites+26.766 ($R^2\;=\;0.69$) and EC of the throughfall of the total amount of the event in management sites = 0.6002${\times}$EC of the throughfall of the beginning of the event in management sites+8.0184 ($R^2\;=\;0.54$). In case of stemflow EC, EC of thestemflow of the total amount of the event in non-management sites = 0.6298${\times}$EC of the stemflow of the beginning of the event in non-management sites+11.582 ($R^2\;=\;0.72$) and pH of the stemflow of the total amount of the event in management sites =0.602${\times}$pH of the stemflow of the beginning of the event in management sites+20.783($R^2\;=\;0.49$).

Restriction endonuclease maps of three plasmids from bacillus thuringiensis serovar israelensis 4Q1 (Bacillus thuringiensis serovar israelensis 4Q1로부터 분리된 plasmid 제한효소지도 작성)

  • Faust, R.M.;;;C.L.Meyers-Dowling;P.E.McCawley
    • Korean Journal of Microbiology
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    • v.23 no.2
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    • pp.122-128
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    • 1985
  • Bacillus thuringiensis serovar israelensis 4Q1 contains 8 different covalently closed-circular (CCC) plasmids of molecular weight 204, 267, 109, 103, 16, 7.6, 6.4, and 5.0kb. The three smallest plasmids, designated pBti6, and pBti8 may prove to be useful as cloning vectors because of thier size and ease of isolation. The three plasmids were incubated separately with 9 different restriction enzymes and 7 of the enzymes tested cleaved one or more of the plasmids. Plasmid pBti6 has a single site for Bg1 II, Pst I and Pvu II, two sites for Bc1 I and Eco RI, and five sites for Hind III. Plasmid pBti7 has a single site for Bam HI and Pst I, two sites for Hind III, and three sites for PvuII. Plasmic pBti8 has a single site for Bam HI, BelI and Hind III, two sites for Eco RI, and three sites for Bgl II and Pvu II. Composite restriction enzyme maps for pBti6, pBti7 and pBti8 were constructed. The sites of restriction enzyme cleavage were determined by single, double and partial digests of the plasmid DNA. All the restriction sites were aligned relative to the single Bgl II(pBti6), Pst I(pBti7) or Hind III(pBti8) site, respectively.

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Surface Chemical Properties of Aqueous Kaolinite and Halloysite: Surface Complexation Modeling (수용액 내 캐올리나이트와 할로이사이트의 표면화학 특성: 표면복합반응 모델링)

  • 장세정;김수진
    • Journal of the Mineralogical Society of Korea
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    • v.17 no.2
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    • pp.157-168
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    • 2004
  • The surface chemical properties of aqueous kaolinite and halloysite were studied using a potentiometric titration experiment and a computer program FITEQL3.2. Among the surface complexation models a constant capacitance model was selected for this study. The 2 sites - 3 p $K_{a}$ s model, in which the surfaces were assumed to have tetrahedral and octahedral sites, was reasonable for the description of the experimental data. The surface charges of both minerals were negative above pH of 4. The higher the pH, the lower the proton surface charge densities of both minerals. The ≡ $SiO^{[-10]}$ site played an important role in cation adsorption in acid and neutral pH range; whereas the ≡ Al $O^{[-10]}$ site was in an alkaline pH range. The optimized intrinsic constants of kaolinite, p $K_{a2(Si)}$$^{int}$, p $K_{al(Al)}$$^{int}$ and p $K_{a2(Al)}$$^{int}$ were 4.436, 4.564, and 8.461 respectively, and those of halloysite were 7.852, 3.885, and 7.084, respectively. The total Si and Al surface sites concentrations of kaolinite were 0.215 and 0.148 mM, and those of halloysite were 0.357 and 0.246 mM. The ratio of Si and Al surface site densities ([≡SiOH]:[≡AlOH]) of both minerals was 1 : 0.69. The total surface site density of kaolinite, 3.774 sites/n $m^2$, was 1.6 times larger than that of halloysite, 2.292 sites/n $m^2$./TEX>.

Preincubation without attB DNA inhibits In Vitro Integrative Recombination of P 1 Mutant attP DNA of Bacteriophage Lambda

  • Yoo, Seung-Ku
    • Journal of Microbiology and Biotechnology
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    • v.5 no.3
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    • pp.132-137
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    • 1995
  • The lambda integrase (lnt) is believed to bind to several arm and core sites of attP DNA in order to facilitate intasome formation. We have done systematic mutagenic analysis on all 5 arm sites and found that P1 is absolutely required for integration while P2 is not. We also found that all 3 P' arm sites(P'1, P'2, and P'3) are required for efficient integrative recombination. P'1, which is an important binding site for excision, also seems to be crucial for integration when preincubation of attP DNA with Int and IHF is performed before recombination. Preincubation assay revealed that preincubation with Int and IHF improved the efficiency of recombination of wild type attP DNA and demolished recombinations of P'1 mutant attP DNAs.

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Chemical Characteristics of Precipitation in Pusan I. Temporal and spatial variation of pH and major ions (부산지역 강우의 화학적 특성 I. pH 및 주요이온의 시ㆍ공간적 변화)

  • Jeon, Eun-Ju;Yang, Han-Sub;Ok, Gon;Kim, Young-Sub
    • Journal of Environmental Science International
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    • v.7 no.5
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    • pp.707-716
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    • 1998
  • The chemical characteristics of precipitation was investigated in Pusan area. Samples were collected from January to November in 1996 at 4 sites, and analyzed pH, major soluble ionic components(C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, N $a^{+}$, $K^{+}$, N $H_4$$^{+}$, $Mg^{2+}$, $Ca^{2+}$). The order of anion and cation concentrations for the initial precipitation were C $l^{[-10]}$ > S $O_4$$^{2-}$ > N $O_3$$^{[-10]}$ , and $Ca^{2+}$ > N $a^{+}$ > N $H_4$$^{+}$$Mg^{2+}$$K^{+}$, respectively. At coastal sites(P1 and P2) C $l^{[-10]}$ and N $a^{+}$ of maritime sources (seasalt) were high, but at inland sites(P3 and P4) nss-C $a^{2+}$ and nss-S $O_4$$^{2-}$ were high. Calcium ion for the initial precipitation showed high value of enrichement factor(EF) relative to seawater composition. The contribution of seasalt to the composition of precipitation was higher at bite P1 (53.5%) than those of the other sites. Throughout the year the concentrations of major ions for the initial precipitation were low in the heavy rain season. The mean pH for the initial precipitation was 5.4 and showed the negative relationship with the precipitaion amount. The S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ do not play an important role in rain acidification due to the high(97%) neutralizing effect of amonia and calcium species.and calcium species.

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Characteristic of Water-soluble Components of PM10 at Taean and Gangneung Sites in Summer Season (태안과 강릉지역 여름철 PM10의 수용성 성분 특성)

  • Park, Seung-Shik;Ko, Jae-Min;Chung, Chang-Hoon
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.3
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    • pp.291-302
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    • 2011
  • [ $PM_{10}$ ]measurements were made at two coastal sites, i.e., Taean and Gangneung, for summer to examine the characterization of water-soluble organic carbon (WSOC) and inorganic ionic species, and to investigate their difference between the sites. The fractions of three major inorganic water-soluble components ($NO_3^-$, $SO_4^{2-}$, and $NH_4^+$) at Taean and Gangneung sites were 30.6% (16.2~62.0%) and 25.6% (13.0~52.5%) of the $PM_{10}$, respectively. $SO_4^{2-}$ is the most dominant species of water-soluble ions at both sites, accounting for up to 20.5% (9.1~44.9%) and 16.3% (5.5~34.2%) of their respective PM10 mass concentrations. Using the paired T-test, $PM_{10}$ (p<0.01), $NO_3^-$ (p<0.05), $SO_4^{2-}$ (p<0.01), $NH_4^+$ (p<0.001), and WSOC (p<0.05) concentrations exhibited strong fluctuations on a daily basis between Taean and Gangneung sites. Relationship between the concentrations of $SO_x$ ($SO_4^{2-}+SO_2$) and CO indicates that the slopes of $SO_x$ /CO were 0.007 and 0.019 in the Taean and Gangneung sites, respectively. The smaller $SO_x$/CO slope in the Taean site could be related to the aged air with wet scavenging of $SO_x$ during transport. The correlation between the concentrations of CO and WSOC suggests that WSOC observed in the Gangneung ($R^2$=0.82) be transported from combustion-related sources, while the WSOC at the Taean site could be formed through atmospheric processing of primary volatile organic species during transport.

Characteristics of Soil Chemical Properties in Abandoned Coal Mine Forest Rehabilitation Areas in Mungyeong, Gyeongsangbuk-do (경상북도 문경시 폐탄광 산림복구지 토양의 화학적 특성)

  • Jung, Mun Ho;Shim, Yon Sik;Kim, Tae Heok;Oh, Ji Young;Jung, Yeong Sang
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.733-737
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    • 2012
  • The objectives of this study were to investigate soil chemical properties for forest rehabilitation and suggest design and management in abandoned coal mine areas in Mungyeong, Gyeongsangbuk-do. Total study sites were 10 sites, and soil analysis particular were soil pH, TOC, total-N, C/N ratio, A.v. $P_2O_5$, and CEC. Because most of study sites showed soil pH from 5.0 to 7.0, it seems that soil pH does not affect growth of vegetation. But soil pH in Danbong1 was acidic (pH 4.6), so it is needed to improve with ameliorant such as limestone. Most of study sites is necessary to manage for organic matter and Nitrogen, because there sites showed lower value of TOC and total-N than general forest. The values of A.v. $P_2O_5$ and CEC were good in most of study sites, so it seems that they do not have effect on vegetation growth. All of soil factors has no regression according to elapsed time after rehabilitation. TOC, total-N and A.v. $P_2O_5$ among soil properties have positive relationship between each other. It is necessary to fertilizer for organic matter and Nitroge because of value in TOC, total-N and C/N ratio. The results of this study were analyzed only one time. So, long-term monitoring for soil properties is important for the correct forest rehabilitation and management.

Extracellular Production of Alpha-Interferon by Recombinant Escherichia coli : Part I. Construction of Expression Vectors (유전자 재조합 대장균을 사용한 Alpha-interferon의 생산과 분비: 제 1 부. 발현벡터의 제작)

  • 노갑수;최차용
    • KSBB Journal
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    • v.5 no.1
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    • pp.49-58
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    • 1990
  • We constructed hybrid plasmids to allow controlled and extracellular production of human alpha-interferon in Escherichia coli. The hybrid plassmids were constructed by transferring alpha-lFN gene from plasmid Hif-2h which has the alpha-lFN gene at PstI restriction site of pBR322, to plasmids pIN -IIIB3 and pIN-IIIC3 at restriction sites between HindIII and BamHI. Plasmids pIN-IIIB3 and pIN-IIIC3 carry E. coli lipoprotein promoter, lac promoter and operator in tandem. The plasmids also have lacl genes which encode for lac repressors, which allows controlled expression of genes cloned to the plasmids by using of inducer IPTG. Lipoprotein signal sequence is located just ahead of cloning sites of the plasmids, which helps cells to excrete or secrete cloned gene products. Plasmid pUC9 was used as a intermediate vector for transferring of alpha-lFN gene from Hif-2h to pIN vectors in order to solve the problem of different restriction sites between Hif-2h and pIN vectors.

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Relation of Acid Depositions and Chlorophyll Concentration in the Pinus thunbergii Leaf (산성강하물과 해송엽 엽록소의 관련성)

  • Lee, Chong-Kyu;Kim, Jong-Kab;Hwang, Jin-Hyeong
    • Journal of agriculture & life science
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    • v.45 no.2
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    • pp.35-41
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    • 2011
  • This study was carried out to investigate the relation of acid depositions and chlorophyll concentration in the Pinus thunbergii leaves. pH of throughfall in Pinus thunbergii forest was 4.20 at industrial sites, and 4.87 at urban sites. Total chlorophyll concentration in leaves were 0.5984 at industrial sites, and 0.6784 at urban sites. The average $SO_2$ concentration in air was 0.029ppm at industrial sites, and 0.011ppm at urban sites. Correlation between chlorophyll concentration in the Pinus thunbergii leaves and acid depositions was pH (r=-0.8769), ${NO_3}^-$ (r=0.6983), ${SO_4}^{2-}$ (r=0.8929), $SO_2$ (r=0.8738), and $NO_2$ (r=0.8523) (p<0.001). respectively. The estimation equation of chlorophyll concentration in the Pinus thunbergii leaf (Y) were given by Y=4.8979 + 0.7698pH + $0.8412{SO_4}^2$ + $0.8673SO_2$, + $0.8767NO_2$+ $0.8767{NO_3}^-$ ($r^2$=0.8873), which coefficients of determination was 0.88.

Modulation of Kex2p Cleavage Site for In Vitro Processing of Recombinant Proteins Produced by Saccharomyces cerevisiae

  • Mi-Jin Kim;Se-Lin Park;Seung Hwa Kim;Hyun-Joo Park;Bong Hyun Sung;Jung-Hoon Sohn;Jung-Hoon Bae
    • Journal of Microbiology and Biotechnology
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    • v.33 no.11
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    • pp.1513-1520
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    • 2023
  • Kex2 protease (Kex2p) is a membrane-bound serine protease responsible for the proteolytic maturation of various secretory proteins by cleaving after dibasic residues in the late Golgi network. In this study, we present an application of Kex2p as an alternative endoprotease for the in vitro processing of recombinant fusion proteins produced by the yeast Saccharomyces cerevisiae. The proteins were expressed with a fusion partner connected by a Kex2p cleavage sequence for enhanced expression and easy purification. To avoid in vivo processing of fusion proteins by Kex2p during secretion and to guarantee efficient removal of the fusion partners by in vitro Kex2p processing, P1', P2', P4, and P3 sites of Kex2p cleavage sites were elaborately manipulated. The general use of Kex2p in recombinant protein production was confirmed using several recombinant proteins.