• Journal of radiological science and technology
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• v.39 no.4
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• pp.595-600
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• 2016

The diagnostic multileaf collimator(MLC) was designed for patient dose reduction in diagnostic radiography We used monte carlo simulation code (MCNPX, LANL, USA) to evaluate efficiency of shielding material for making diagnostic MLC as preliminary study. The diagnostic radiography unit was designed using SRS-78 program according to tube voltage (80,100,120 kVp) and acquired energy spectrums. The shielding material was SKD11 alloy tool steel that is composed of 1.6% carbon(C), 0.4% silicon(Si), 0.6% manganese (Mn), 5% chromium (Cr), 1% molybdenum(Mo) and vanadium(V). The density of it was $7.89g/cm^3$.Using tally card 6, we calculated the shielding efficiency of MLC according to tube voltage. The results was that 98.3% (80 kVp), 95.7 %(100 kVp), 93.6% (120 kVp). We certified efficiency of diagnostic MLC fabricated from SKD11 alloy steel by monte calro simulation. Based on the results, we designed the diagnostic MLC and will develop the diagnostic MLC for reduction of patient dose in diagnostic radiography.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.26-33
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• 1988

To investigate the effects of paper sludge on the growth response of paddy rice, paper sludge was applied to pots at the rate of either 300, 600, 900 or 1,200 kg/l0a which was either preadjusted at a C/N ratio of 30 : 1 or not adjusted. The effects were compared with those of the control. 1. Plant heights, number of tillers and dry weight were significantly reduced with the increasing application of paper sludge in the early stages of rice growth, whereas opposite results were observed after the heading stage when treated with C/N ratio preadjusted paper sludge. 2. The uptake of $N,P_2O_5,K_2O$ and $SiO_2$ by rice plants grown in paper sludge treated soil was significantly reduced in the early stages of rice growth. Conversely, uptake was enhanced in the C/N ratio preadjusted plot in the young panicle formation stage. 3. Zn, Cu and Cd content in rice straw was in the range of $39{\sim}101$, $0{\sim}0.11$ and $0.03{\sim}0.14ppm$, respectively, and Pb and Cr in rice straw were not detected at all. However, there was no difference in the content of all these heavy metals in rice straw irrespective of treatment.

• The Journal of the Society of Stroke on Korean Medicine
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• v.7 no.1
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• pp.34-39
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• 2006

Objectives and methods : The Euibujipsung is the one of the huge-scale encyclopedias about Oriental Medicine. To investigate the most frequently used acupoints for hemiparesis after stroke, we used Euibujipsung CR-ROM database with several key words concerned with motor weakness (半身不遂 不遂不隨 癱瘓 中臟 中腑 風痱, etc.). Results : In the result, we found five popular acupoints (GV20, LI11, LI15, ST36 and GB39), and four meridians (Stomach, Gall bladder, Large intestine and Small intestine). We also found that the Yang meridians were cited more frequently than the Yin. Conclusion : Therefore we think that these findings can give further ideas to clinical practice and research fields for stroke rehabilitation in Oriental medicine.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.393-398
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• 2012

We investigated the changes in chemical properties of paddy field soils at 300 different sampling sites containing 4 topography in Jeonbuk province, Korea. The soil samples were collected 43.0% from local valley and fans, 39.3% from fluvio-marine deposits, 15.0% from alluvial plains, and 2.7% from diluvium sites. The optimal values of soil properties in the total soil samples were as follows: 65.3% of total samples in soil pH value, 48.3% of total samples in cation exchange capacity (CEC) value, and 22.3% of total samples in available phosphorus content, whereas the deficient values of soil properties were 63.3% of total samples in soil organic matter (SOM) content, 75.7% of total samples in available silicate content, and 61.3%, 51.0%, and 59.3% of total samples in exchangeable $K^+$, $Ca^{2+}$, and $Mg^{2+}$ concentrations, respectively. There were different soil types in the paddy fields: that is, 34.4% immature paddy and 33.6% sandy paddy in the local valley and fans, 57.8% sandy paddy in the alluvial plains, 47.4% normal paddy in the fluvio-marine deposits, and 75.7% immature paddy in the diluvium. Soil textures were also different: 53.5% loam in the local valley and fans, 37.8% sandy loam in the alluvial plains, and 55.1% silty loam in the fluvio-marine deposits. Soil pH and SOM contents were not different among the different topographical sampling sites. However, the mean value of available phosphorus content, 224 mg $kg^{-1}$, was exceeded optimal values in the diluvium. The contents of exchangeable cations were optimal in all the sites, except exchangeable $Ca^{2+}$ contents in the local valley and fans. The contents of available silicate ranged between 112 and 127 mg $kg^{-1}$ in all the sites, which were lower than optimal value. In addition, soil pH values were proportionally correlated to the order of available silicate, exchangeable $Ca^{2+}$, $Mg^{2+}$, $Na^+$, CEC, and exchangeable $K^+$. The contents of SOM were proportionally correlated to the order of CEC, available $P_2O_5$, exchangeable $Ca^{2+}$, and available silicate. The contents of heavy metals, Cd, Cr, Cu, Ni, Pb, and Zn, were only 10% of the threshold levels of the metals, and As content was about 20 to 30% of the threshold level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1873-1879
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• 2010

This study was conducted to estimate the heavy metal contents of vegetables available on the markets in Seoul area. Concentrations of mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), chrome (Cr), nickel (Ni), copper (Cu), and zinc (Zn) were measured in 300 samples using a mercury analyzer and inductively coupled plasma optical emission spectrometer (ICP-OES) after wet digestion. The average values of heavy metals in vegetables were as follows [mean (minimum~maximum), mg/kg]; Hg: 0.0005 (N.D~0.007), Pb: 0.011 (N.D~0.259), Cd: 0.012 (N.D~0.188), As: 0.002 (N.D~0.142), Cr: 0.100 (0.019~0.954), Ni: 0.093 (0.003~1.231), Cu: 1.098 (0.072~36.29), and Zn: 3.48 (0.485~21.31). The heavy metal contents of vegetables available on the markets in Seoul were almost the same as or lower than those reported in other studies. The weekly average intakes of mercury, lead and cadmium from vegetables take 0.44~7.71% of PTWI (Provisional Tolerable Weekly Intakes) that the FAO/WHO Joint Food Additive and Contaminants Committee sets for evaluation of food safety.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.178-185
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• 2005

Purpose : The purpose of this study was to evaluate the outcome of children with juvenile myelomonocytic leukemia(JMML) treated with allogeneic hematopoietic stem cell transplantation(allo-HSCT). Methods : Eleven JMML patients aged 8-39 months underwent allo-HSCT. The sources of grafts were unrelated donors(n=7), HLA-matched siblings(n=3) and an HLA 1-antigen mismatched familial donor. All patients had received chemotherapy ${\pm}13$-cis-retinoic acid(CRA) before transplant, and CRA was used, posttransplant, in six patients. Results : Only three patients were in complete remission(CR) at the time of transplantation. Initial chimeric status revealed complete donor chimerism(CC) in five patients, mixed chimerism(MC) in five and autologous recovery(AR) in one. One patient with MC having persistent splenomegaly eventually turned to CC and CR after rapid tapering of cyclosporine, combined with daily use of CRA. An AR case relapsed shortly after transplant but was rescued with second, unrelated cord blood transplantation. Ultimately, six patients are alive, event-free, with a median follow-up of 15.5 months posttransplant. All three deaths occurred in patients who failed to achieve CC, leading to disease progression. Conclusion : We suggest that graft-versus-leukemia effect play an important role and CRA a possible role in posttransplant leukemic involution in JMML. In patients whose leukemic burden is still high with MC after transplant, early tapering of immunosuppressants and introduction of CRA might provide a chance of a cure for some patients.

• Journal of the Korean Society of Radiology
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• v.5 no.3
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• pp.111-120
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• 2011

A purpose of study is to develop optimization and radiation dose exposure reference level by measuring actual radiation dose in condition of quality control of mammography equipment for 39 clinics. The result were as follows. First, we measured T-test separating radiology from general clinic. According to the test, mAs was measured at average 78.58 mAs; radiology at 80.16 mAs and general clinic at 77.22 mAs. And, kerma rate was measured at average 7.71 mGy/mR; radiology at 8.94 mGy/mR and general clinic at 6.66 mGy/mR. HVL was measured at average 0.42 mmAl; radiology at 0.40 mmAl and general clinic at 0.43 mmAl. Average glandular dose was measured at average 1.14 mGy; radiology at 1.09 mGy and general clinic at 1.19 mGy. Second, we measured value of mAs, HVL, processing method and so on dividing two groups. And, we compared and analyzed average value measured using T-test. As a result, there was significance level in SID(P<0.05). There was significance level in mAs(P<0.05). Because processor was measured at 1.00 mGy and CR at 1.17 mGy according to the processing method of radiology. Third, according to the correlation analysis, radiology had significance level between average glandular dose and mAs and general clinic had significance level between average glandular dose and SID(P<0.05). Forth, as a result of regression analysis, mAs affected 22.7%t of average glandular dose and SID affected 21.7% of average glandular dose, which had significance level(P<0.05). And, mAs affected 29.0% of average glandular dose in radiology and SID affected 29.1% of average glandular dose in general clinic, which was most influential.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.469-475
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• 2002

The rotating biological contactor (RBC) was tested for treatment of aquacultural water in a pilot-scale recirculating aquaculture system. Performance of RBC on the treatment of nitrogen source such as total ammonia nitrogen (TAN), nitrite nitrogen and nitrate nitrogen and chemical oxygen demand (CODcr.) was evaluated. A system was stocked with nile tilapia at an initial rearing densities of $5\%$ and $7\%$ over 30 days. As increasing rearing density from $5\%$ to $7\%$, the TAN removal rates was increased from $39.4 g/m^3{\cdot}day$ to $86.0 g/m^3{\cdot}day$. But TAN removal efficiency was decreased from $24.5\%$ to $16.0\%$. The removal rate of $COD_Cr$ was higher than TAN. The RBC as an aerator was also evaluated for increasing dissolved oxygen concentration. For $5\%$ and $7\%$ of rearing density, the average aeration rate were $280 g/m^3{\cdot}day$ and $255 g/m^3{\cdot}day$, respectively.

• Korean Journal of Animal Reproduction
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• v.22 no.3
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• pp.293-300
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• 1998

The objective of this study was to determine effects of $\beta$-mercaptoethanol ($\beta$-ME) and cyst-eine (CYS) on the development of bovine em-bryos obtained from in vitro matured and fertil-ized oocytes. Cumulus-oocyte-complexes (COC-s) were matured in micro-drop of TCM-199 medium containing 10% FBS, 17$\beta$-Estradiol and FSH-p under paraffin oil at 39$^{\circ}C$ for 24 hrs. The fertilization of COC were induced in Fert-TALP medium supplemented with PHE, heparin, BSA and then the fertilized oocytes were cultured in CR1aa medium for 24 hrs. To investigate the effects of the agents on the development of the embryos, the embryos developed to the late 2-cell stage were cultured in the media with and without $\beta$-ME, CYS for 9 days. In experiment 1, to select appropriate concentration of $\beta$-ME and CYS during whole culture period (9 days), various concentrations of $\beta$-ME and CYS were add ded to the CR1aa medium. Addition of 25TEX>$\mu$M of $\beta$-ME and O.1mM of CYS to the culture medium 1 increase the incidence of embryos developed to the blastocyst. In experiment 2, we evaluated the effects of 25$\mu$M of $\beta$-ME and O.1mM of CYS addition on the blastocyst formation when emb bryos at different stages were exposed to 25$\mu$M $\beta$-ME and O.1mM of CYS. $\beta$-ME and CYS enhanced in vitro development of embryos to the blastocyst stage. The effect was greater in 8-ceII to morula embryos than in embryos fewer than 2-cells at the initiation of treatment. These results suggested that the addition of 25$\mu$M B-ME and O.1mM cysteine enhanced development to the blastocyst and hatching stage of in vitro derived bovine embryos, also addition of $\beta$-ME and cysteine were effective later stage embryo than early embryo development.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.494-500
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• 1996

Uptake of hen metal ions by water dropwort (Oenanthe stolonifera DC.) and its cadmium-binding protein were studied to probe for good method to remove heavy metal contaminants from environments. The plant was cultured in the culture medium (pH 7.0) containing the various concentrations of $Cd^{2+}$, $Cr^{3+}$ or $Pb^{2+}$, for 3 and 7 days. The residual heavy metals deposited in roots linearly increased as the metal ions concentration increased up to 17 ppm for $Cd^{2+}$, 20 ppm for $Cr^{3+}$ and 50 ppm for $Pb^{2+}$. Above these concentrations, the plant growth was inhibited and the uptake rates of the metal ions decreased. The heavy metals absorbed by the plant were mostly deposited in roots. In particular, the residual concentration of lead in roots was about four times higher than those of cadmium and chromium. When cultured in the medium containing 20 ppm of each metal ion, 80% of cadmium, 90% of cromium and 96% of lead were deposited in roots out of the total residual metal ions in the plant. These values correspond to 6.1 mg of cadmium, 5.2 mg of chromium and 23.6 mg of lead per one gram of roots tissue on a dry weight basis. A cadmium-binding protein was partially purified by extraction, gel filtration and DEAE-Cellulose chromatography from water dropworts that was grown in the medium containing 20 ppm $Cd^{2+}$. The purified protein was a single band on SDS- and non-denaturing- polyacrylamide gel electrophoresis. Its molecular mass was estimated to be ca. 5,000 dalton by gel filteration. Analysis of amino acid composition of the protein indicated that it had a typical amino acid composition of heavy metal-binding protein in that it contained 27% of acidic amino acids and 9.9% of cysteine. However, it is likely that the protein is a new plant metal-binding protein, since its amino acid composition is somewhat different from those of phytochelatins that have been known so far.