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Theoretical Effects of Altered Biological and Chemical Properties on Salinity Tolerance of Acacia seeds

  • S. Rehman;P.J.C. Harris;Kou, Chei-Wei;Rha, Eui-Shik
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2003.10b
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    • pp.43-43
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    • 2003
  • Multiple regression equations (Rehman et al. 2000) have been developed to predict the salinity tolerance of Acacia seeds, expressed as the I$\sub$50/ (the concentration of NaCl required to reduce final germination to 50% of the control value in DW). Accurate predictions can be made using one or more chemical and biological seed parameters. In this study the theoretical effect of varying final germination percentage in distilled water, germination rate in distilled water. (Rate), Ca$\^$2+/ or K$\^$+/ contents and their ratios, as independent factors or related factors, on the predicted salinity tolerance (I$\sub$50/) of Acacia species was investigated. Simulation of the effects of changing final germination, rate, calcium and potassium suggest the possibility of practical application of these results to modify the salinity tolerance of seeds. The predicted I$\sub$50/ increased with increasing final germination. Similarly, the higher the rate of germination, the higher the predicted salt tolerance of Acacia species. The Ca$\^$2+/ content of seeds was found to be positively correlated with I$\sub$50/. Species with higher Ca$\^$2+/ contents had a higher I$\sub$50/. This suggests that I$\sub$50/ might be increased by increasing the Ca$\^$2+/ contents of seeds by pretreatment with calcium salts or by supplying these to the mother plants.

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The Effect of Unleached Agents on the Stabilization/Solidification of Hazardous Sludge Containing Heavy Metals (有害슬러지 固形化에 따른 重金屬 溶出防止剖의 影饗)

  • 이성호
    • Journal of Environmental Health Sciences
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    • v.19 no.2
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    • pp.46-54
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    • 1993
  • This study was carried out on the stabilized/solidified treatment for the reducing leachability of hazardous heavy metals copper, lead, chromium and cadmium in the hazardous sludge which treated to be unleached heavy metals by sodium diethyl dithiocarbamate. Cement matrix was analyzed for the leachability of 24 hrs and dynamic leaching test, structure and the optimum condition for the stabilization and solidification of the hazardous sludge. In 28 days of curing time the unconfined compressive strength was 21.5 kg/cm$^2$ at the ratio of portland cement (0.5)+fly ash (0.25) and 23.5 kg/cmz at the ratio of portland cement (0.5)+fly ash (0.25) + cake (0.25). High concentration of Pb, Cr and Cd in the sea water and Cu in the distilled water were leached at the dynamic leaching test. The concentration of leaching heavy metals for specimens which were tested 24 hrs were found low leachability with decreasing pH of leachant. According to dynamic leaching test, the low level of copper, lead, cadmium and chromium were leached in the cement matrix with sodium diethyl dithiocarbamate. But the effective diffusion coefficient of unleached cement matrix which was treated sodium diethyl dithiocarbamate was decreased above 2 times than that of cement matrix. The relation of leachant renewal period (Y) and cumulative fraction ion leached (X) was the following regression equations. Solidification with unleached agent. Y$_{Cu}$ = 1413752X + 247, Y$_{Pb}$ = 223501IX + 214, Y$_{Cr}$ = 8310601X - 472, Y$_{Cd}$ = 168787X + 1061 The structure of' solidified matrix with X-ray diffraction analysis was composed more Ca(OH)$_2$, Si, Mg(OH)$_2$ and Al in the unleached cement matrix than those in cement matrix.

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The Physio-Chemical Characteristics of Aerosol in Urban Area During Snowfall (강설시 도심지역 에어러솔의 물리.화학적 특성)

  • 김민수;이동인;유철환
    • Journal of Environmental Science International
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    • v.10 no.3
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    • pp.201-208
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    • 2001
  • To investigate the physio-chemical components and properties of aerosol particles in urban area sampling of aerosol particles was carried out in the campus of Hokkaido University, Sapporo, Japan, during snowfall. Aerosol particles were collected on millipore filter papers using a low volume air sampler. Their shapes, sizes and chemical components were analyzed by a SEM(Scanning Electron Microscope) and an EDX(Energy Dispersive X-ray). As a results, ice crystals of dendrite and column types were predominantly shown at mature and developing stage of snowfall intensity. The denerite and sector plate types of ice crystals were mainly originated from the sea but column types were come from soil. Scavenging effect by snowfall was greatly also shown at dendrite type ice crystals that embryo was fully developd. Al, Si elements were shown at high frequencies as compared with others. Na, Cl components were especially shown at high frequencies under the sea-breeze wind during snowfall. Anthropogenic aerosol particles had shown with irregular shapes and sizes, relatively. Mainly 3-7$\mu$m aerosol particles were abundant and coarse particles also could be seen during snowfall. Ca, Zn, Fe components mainly caused by spike tires from vehicles in winter season were dominant before snowfall, however the element S mainly caused by human activity was rich after snowfall. The pH values of snow in Sapporo city were higher than those at coastal area. The concentration of chemical components in aerosol particles was also affected by surface winds. Aerosol particles in urban area, Sapporo were mainly affected by human activities like vehicles and combustion with wind system. And their types were related with snowfall intensity.

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The effect of thermocycling on the bonding of different restorative materials to access opening through porcelain fused to metal restorations

  • Al-Moaleem, Mohammed M.;Shah, Farhan Khalid;Khan, Nausheen Saied;Porwal, Amit
    • The Journal of Advanced Prosthodontics
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    • v.3 no.4
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    • pp.186-189
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    • 2011
  • PURPOSE. Porcelain fused to metal (PFM) crowns provide the best treatment option for teeth that have a large or defective restoration. More than 20% of teeth with PFM crowns or bridges require non-surgical root canal treatment (NSRCT). This may be due to the effect of restorative procedures and the possible leakage of bacteria and or their by-products, which leads to the demise of the tooth pulp. Thus, this study was planned to compare the ability of the restorative materials to seal perforated PFM specimens. MATERIALS AND METHODS. The study evaluates the ability of amalgam, composite or compomer restorative materials to close perforated PFM specimen's in-vitro. Ninety PFM specimens were constructed using Ni-Cr alloys and feldspathic porcelain, and then they were divided into 3 groups: amalgam (A), composite + Exite adhesive bond (B) and compomer + Syntac adhesive bond (C). All the PFM samples were embedded in an acrylic block to provide complete sealing of the hole from the bottom side. After the aging period, each group was further divided into 3 equal subgroups according to the thermocycling period (one week for 70 cycles, one month for 300 cycles and three months for 900 cycles). Each subgroup was put into containers containing dye (Pelikan INK), one maintained at $5^{\circ}C$ and the other at $55^{\circ}C$, each cycle for 30 sec time. The data obtained was analyzed by SPSS, 2006 using one way ANOVA test and student t-test and significant difference level at (P<.01). RESULTS. The depth of dye penetration was measured at the interfaces of PFM and filling materials using Co-ordinate Vernier Microscope. The lowest levels of the dye penetration for the three groups, as well as subgroups were during the first week. The values of dye leakage had significantly increased by time intervals in subgroups A and C. CONCLUSION. It was seen that amalgam showed higher leakage than composite while compomer showed the lowest level of leakage.

Removal of mid-frequency error from the off-axis mirror

  • Kim, Sanghyuk;Pak, Soojong;Jeong, Byeongjoon;Shin, Sangkyo;Kim, Geon Hee;Lee, Gil Jae;Chang, Seunghyuk;Yoo, Song Min;Lee, Kwang Jo;Lee, Hyuckee
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.103-103
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    • 2014
  • Manufacturing of lens and mirror using Diamond Turning Machine (DTM) offers distinct advantages including short fabrication time and low cost as compared to grinding or polishing process. However, the DTM process can leave mid-frequency error in the optical surface which generates an undesirable diffraction effect and stray light. The mid-frequency error is expected to be eliminated by mechanical polishing after the DTM process, but polishing of soft surface of ductile aluminum is extremely difficult because the polishing process inevitably degrades the surface form accuracy. In order to increase its surface hardness, we performed electroless nickel plating on the surface of diamond-turned aluminum (Al-6061T6) off-axis mirrors, which was followed by the 6-hour-long baking process at $200^{\circ}C$ for improving its hardness. Then we polished the nickel plated off-axis mirrors to remove the mid-frequency error and measured polished mirror surfaces using the optical surface profilometer (NT 2000, Wyko Inc.). Finally, we ascertained that the mid-frequency error on the mirror surface was successfully removed. During the whole processes of nickel plating and polishing, we monitored the form accuracy using the ultra-high accurate 3-D profilometer (UA3P, Panasonic Corp.) to maintain it within the allowable tolerance range (< tens of nm). The polished off-axis mirror was optically tested using a visible laser source and a pinhole, and the airy pattern obtained from the polished mirror was compared with the unpolished case to check the influence of mid-frequency error on optical images.

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Health Promoting Behaviors and Quality of Life of Korean Women with Arthritis (여성 관절염 환자의 건강증진과 삶의 질)

  • 오현수
    • Journal of Korean Academy of Nursing
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    • v.23 no.4
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    • pp.617-630
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    • 1993
  • Factors related to health promotion activities and quality of life in Korean women with arthritis have not been clearly identified. Predictors of health promotion might be identified that will enhance the well - being of this group. Accordingly, the findings of the study will contribute additional information about the relationship between health promotion and quality of life and will add to the research on quality of life of individuals with a leading cause of disability--arthritis. The purpose of the study was to examine the relationship of selected background factors (years of illness, perceived severity of illness, uncertainty in illness), perceived self- efficacy, and health promoting behaviors to the quality of life of Korean women with arthritis. A cross - sectional descriptive design was used in this study to investigate relationships among the variables of interest. The sample was composed of 96 women who had arhtrits and visited large university hospital in Seoul for regular check up or pre-scription of medication. The purpose of a descriptive correlational design was to determine the absence or presence of relationships among variables that were measurable (Polit & Hungler, 1981, p.147). The design of this study was appropriate because it yielded answers to the research questions and hypotheses regarding the relationships among the model variables. the Questionnaire contained demographic information, translated Mishel Uncertainty in illness Scale-Community form (MUIS-C) (Mishel, 1987), translated and modified Disease Course Graphic Scale(DCGS) which was developed by Braden (1990), translated Sherer. et al.’s General Self-Efficacy Scale (1982), The Health -Promoting Lifestyle Profile (HPLP), developed by Walker, Sechrist, and Fender (1987) and traslated to Korean by Ha, and quality of life was measured by Face Scale (Andrew, 1976). Several steps of verification for the translation process were carefully conducted. Data analysis included descriptive correlational statistics and multiple regression techniques. Health promotion was the only contributor to pre-dict quality of life. Results showed that enabling cognitive perceptual factor (self-efficacy) mediates the disruptive force (uncertainty in ill-ness) on achieving a health promoting self- help behavior. The findings of this study also indicated that illness - related variable of severity of illness was mediated by health promotion, which buffered it's impact on quality of life.

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Availability Review of Tailings from the Sangdong Tungsten Mine as a Material for Construction (건설용 재료로서 상동광산광미의 활용성 검토)

  • Kim, Yong-Jic;Kim, Young-Jin;Choi, Yun-Wang;Kim, Sang-Chel
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.1 no.3
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    • pp.204-210
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    • 2013
  • This study has focused on the possibility for recycling tailings from the Sangdong tungsten mine (TA) as admixture for concrete. TA has been accumulating for several decades in Sangdong, a region in Korea, and there is a growing demand for alternative uses for this hazardous substance. In particular, the use must be in accordance with the hazardous materials stipulations under the Korean waste control act. This study showed that TA presented pH of 8.0-9.3, 18.7-22.0% of water content, 2.7% of maximum ignition loss. The chemical composition of TA showed minute differences from each depth of sampling that represented approximately 50% of $SiO_2$ and 13% of both $Al_2O_3$ and $Fe_2O_3$. The chemical composition of Cd, Cu, Zn and Pb from mortar incorporating TA showed lower levels of hazardous materials which met the specifications of the waste control act in Korea. The TA mortar also appeared very effective for stabilizing/solidifying heavy metals particularly when used in conjunction with SG.

Photosynthetic Activity of Quercus acutissima Seedlings Grown under Artificially Acidified Soil Conditions (토양산성화 조건하에서 생육시킨 상수리나무 묘목의 광합성 활성)

  • Jin, Hyun-O;Bang, Sun-Hee;Lee, Choong-Hwa
    • Journal of Korean Society of Forest Science
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    • v.99 no.6
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    • pp.843-848
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    • 2010
  • The effects of soil acidification on the photosynthetic activity of Quercus acutissima seedlings were investigated. We measured the growth and photosynthetic activity of the seedlings in relation to soil acidification. The dry weights of the seedlings were reduced according to the amount of $H^+$ in the soil. The concentrations of Al in needles at the 90 meq $H^+$ were significantly higher than those at the control. The contents of chlorophyll in needles at 90 meq $H^+$ were significantly lower than those at the control. The net photosynthetic rates of the seedlings in the acidified soil were reduced by increasing the amount of $H^+$ to the soil. The carboxylation efficiencies(CE) of photosynthesis were reduced in the seedlings grown in the acidified soil. These results suggested that the soil acidification induced the inhibition of photochemical reactions and $CO_2$ fixation of photosynthesis.

Drastic Brightness and Color Variations of the New Discovered Polar OTJ 071126+440405

  • Kim, Yong-Gi;Yoon, Joh-Na;Andronov, Ivan L.;Breus, Vitalii V.;Dubovsky, P.;Chinarova, Lidia L.;Han, Won-Yong
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.59-59
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    • 2012
  • Self-consistent mathematical model of the exotic object OTJ 071126+440405= CSS 081231:071126+440405 is discussed. The system was discovered as a polar at the New year night 31.12.2008/01.01.2009 by D.Denisenko (VSNET Circ), and we have initiated an international campaign of photometric and polarimetric observations of this object (totally -80 runs in Ukraine, Korea, Slovakia, Finland, USA) as a part of the "Inter-Longitude Astronomy" (ILA) project on monitoring of variable stars of different classes (Andronov et al., 2003). Here we present the geometrical and physical model of the system in the low luminosity state and in the intermediate luminosity state as well as in the high luminosity state. As the system is of -20 mag at minimum, no spectral observations were made to determine parameters of the red dwarf. From the statistical relationship, the mass of the red dwarf is estimated to be -0.165 solar masses, for the white dwarf (from eclipse duration) - from 0.5 to 1.76 solar masses. As the system resembles ER UMa in some characteristics, the lower value may be assumed. The inclination of the system and other physical parameters are estimated. The object is an excellent laboratory to study multiple physical processes in the magnetic systems.

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Correlation between Expression Level of Gene and Codon Usage

  • Hwang, Da-Jung;Han, Joon-Hee;Raghava, G P S
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2004.11a
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    • pp.138-149
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    • 2004
  • In this study, we analyzed the gene expression data of Saccharomyces cerevisiae obtained from Holstege et al. 1998 to understand the relationship between expression level and nucleotide sequence of a gene. First, the correlation between gene expression and percent composition of each type of nucleotide was computed. It was observed that nucleotide 'G' and 'C' show positive correlation (r ${\geq}$ 0.15), 'A' shows negative correlation (r ${\approx}$ -0.21) and 'T' shows no correlation (r ${\approx}$ 0.00) with gene expression. It was also found that 'G+C' rich genes express more in comparison to 'A+T' rich genes. We observed the inverse correlation between composition of a nucleotide at genome level and level of gene expression. Then we computed the correlation between dinucleotides (e.g. AA, AT, GC) composition and gene expression and observed a wide variation in correlation (from r = -0.45 for AT to r = 0.35 for GT). The dinucleotides which contain 'T' have wide range of correlation with gene expression. For example, GT and CT have high positive correlation and AT have high negative correlation. We also computed the correlation between trinucleotides (or codon) composition and gene expression and again observed wide range of correlation (from r = -0.45 for ATA r = 0.45 for GGT). However, the major codons of a large number of amino acids show positive correlation with expression level, but there are a few amino acids whose major codons show negative correlation with expression level. These observations clearly indic ate the relationship between nucleotides composition and expression level. We also demonstrate that codon composition can be used to predict the expression of gene in a given condition. Software has been developed for calculating correlation between expression of gene and codon usage.

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