• Reproductive and Developmental Biology
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• v.28 no.2
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• pp.119-126
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• 2004

The present study was carried out to examine the effect of four different media (NCSU (North Carolina State University)-23, PZM (Porcine Zygotes Medium)-3, PZM-4 and TCM (Tissue Culture Medium)-l99) and two oxygen concentrations (39 , 5% $O_2$, 5% $CO_2$ and 90% $N_2$, 5% $CO_2$ in air) on in vitro production of porcine IVM/IVF embryos. The results were summarized as follows: The rates of GVBD and nuclear maturations were not significantly different (p>0.05) for 44 hours of culture with four media in two oxygen concentrations. The rates of polyspermy, penetrated sperm(s) and male and female prouclei formation were not significantly different (p>0.05). among four media in two oxygen concentrations. The cleavage rates were not significantly different (p>0.05) among four media in two oxygen concentrations. At day 7 under gas atmosphere of 5% $O_2$, 5% $CO_2$ and 90% $N_2$, the blastocyst formation was significantly higher (p<0.05) in PZM-3 (19.9$\pm$2.4) than other media. Also, NCSU-23 medium gave high rate of blastocyst formation at day 7 under gas atmosphere of 5% $CO_2$ in air (p<0.05). Based on the result of differential staining of porcine blastocyst at dat 7, inner cell mass cell and total cell numbers were not significantly different (p>0.05) among four media in two oxygen concentrations. However, the observed total cell number was higher in PZM-3 medium (36.8$\pm$6.5) than other madia. In conclusion, these results suggested that in vitro production of porcine embryos in PZM-3 medium under a gas atmosphere of 5% $O_2$, 5% $CO_2$ and 90% $N_2$ was effective on the blastocyst formation rate and total blastocyst cell number.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.153-163
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• 2002

In vitro matured porcine oocytes have very small volume of perivitellinspace (PVS). In these respect, the effect of sucrose and polybrene on the efficiency of gene transfer was investigated. As a gene (hGH) transfer vehicle, vesicular stomatitis virus glycoprotein pseudotyped retroviral vector (VSV-G) was used. Sucrose treatment has no detrimental effect on the rates of cleavage and resulted in the enlargement of PVS for the efficient introduction of retroviral vector stocks. Introduction rates of retrovirus in 0.5, 1, 2, 3 % sucrose treatment group were higher than that of the non-treatment group (39.3, 43.3, 35.7, 40.7 % vs. 8.3 %), respectively. In addition, we observed that sucrose pretreatment during injection procedure significantly reduce the frequency of polyspermy. In general, polybrene is a polycation essential for retrovirus transduction. The groups with the addition of 0.5, 5, 50$\mu\textrm{g}$/$m\ell$ polybrene exhibited a significant effect on gene transfer compared to that of the non-addition group (56.5, 50.0, 57.1 % vs. 34.6 %), respectively But, when the oocytes were co-injected with retrovirus and 50$\mu\textrm{g}$/$m\ell$ polybrene, the rates of cleavage and blastocyst development were 43.3 and 4.6%, respectively. This rates were lower than those of the non-addition group (70.0 and 17.3 %). In conclusion, sucrose pretreatment have increased efficiency of retroviral mediated gene transfer in porcine oocytes with no damage on in vitro fertilization and embryo development. In addition, sucrose pretreatment was beneficial in polyspermy inhibition. Presence of polybrene during microinjection showed a beneficial effect on the gene transfer in porcine oocytes, in low concentration. And these results will provide an useful tool for production of transgenic pigs by retroviral mediated gene transfer.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.40-46
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• 2000

To select the effective fungicides for the control of leaf spot disease of jujube tree (Zizyphus jujuba) caused by Phoma sp., inhibitory effects of 26 fungicides for mycelial growth were investigated at $250{\mu}g\;a.i./m{\ell}$. In the test, eight fungicides were selected and minimum inhibitory concentration (MIC) for mycelial growth and an inhibitory effect for spore germination were investigated. Among the fungicides, myclobutanil, hexaconazole, and triflumizole were excluded in control effect tests because of their relatively high MICs. MICs were ranged $10-50{\mu}g\;a.i./m{\ell}$ for benomyl, carbendazim + kasugamycin (CK), and thiophanate-methyl. triflumizole (TT), and $50-250{\mu}g\;a.i./m{\ell}$ for iprodione + propineb (IT) and iminoctadine-triacelate (IT). However, benomyl and IP showed very low inhibitory effect on conidial germination. When the fungicides were sprayed on the seedlings before the leaves were inoculated with conidial suspension of Phoma sp., the protective values of CK and TT were around 70% at 1,000 ppm and around 90% at 2,000 ppm. The protective values were around 70% at 2,000 ppm (benomyl), 4,000 ppm (IP), and 8,000 ppm (IT). When the fungicides were sprayed after inoculation, benomyl showed the highest curative values of over 90% at 1,000 ppm and the values of CK and TT ranged $70{\sim}80%$ at 1,000 ppm. However, IP and IT had little or no effect on therapy of the disease. IT caused necrotic phytotoxicity on the leaves of jujube seedlings. As results, the best fungicides for the protection of jujube trees from leaf spot disease were CK (2,000 ppm) and TT (2,000 ppm) and for the remedy of the tree, benomyl (1,000 ppm) was the best. Therefore, alternate application of benomyl and CK or TT will be effective in the disease control.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.2
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• pp.183-193
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• 2018

Currently, the Korea Atomic Energy Research Institute (KAERI) is planning to build the Ki-Jang Research Reactor (KJRR) in Ki-Jang, Busan. It is important to safely dispose of low-level radioactive waste from the operation of the reactor. The most efficient way to treat radioactive waste is cement solidification. For a radioactive waste disposal facility, cement solidification is performed based on specific waste acceptance criteria such as compressive strength, free-standing water, immersion and leaching tests. Above all, the leaching test is important to final disposal. The leakage of radioactive waste such as $^{137}Cs$ causes not only regional problems but also serious global ones. The cement solidification method is simple, and cheaper than other solidification methods, but has a lower leaching resistance. Thus, this study was focused on the development of cement solidification for an enhancement of cesium leaching resistance. We used Zeolite and Loess to improve the cesium leaching resistance of KJRR cement solidification containing simulated KJRR liquid waste. Based on an SEM-EDS spectrum analysis, we confirmed that Zeolite and Loess successfully isolated KJRR cement solidification. A leaching test was carried out according to the ANS 16.1 test method. The ANS 16.1 test is performed to analyze cesium ion concentration in leachate of KJRR cement for 90 days. Thus, a leaching test was carried out using simulated KJRR liquid waste containing $3000mg{\cdot}L^{-1}$ of cesium for 90 days. KJRR cement solidification with Zeolite and Loess led to cesium leaching resistance values that were 27.90% and 21.08% higher than the control values. In addition, in several tests such as free-standing water, compressive strength, immersion, and leaching tests, all KJRR cement solidification met the waste acceptance or satisfied the waste acceptance criteria for final disposal.

• Applied Biological Chemistry
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• v.22 no.2
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• pp.109-122
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• 1979

Present study was carried out to reduce residual toxicity of BHC insecticides inherent in the organochlorine pesticides. For This end, r-isomer, the most potent insecticidal component among the BHC stereoisomers, was isolated and thus fortified by means of solvent precipitation. In parallel, 3-(2,4,5-trichlorophenyl)-1-methyl urea was prepared in good yield from technical BHC via 1,2,4-trichlorobenzene, 1,2,4,-trichloronitrobenzene, and 2,4,5-trichloroaniline. In addition, certain merit of the compound which make it possible to use as a herbicide is discussed. The results are summarized as follows; 1. Recrystallizing technical BHC from methanol-water binary solvent system, r-isomer was enriched to 49.7% at 95% recovery of r-isomer. 2. By partitioning technical BHC in 85% of methanolic solution into chloroform, r-isomer was fortified to 89.6% at 90.5% recovery of r-isomer. 3. Yield of 1,2,4-trichlorobenzene from technical BHC was greatly dependent upon concentration of alkalies and to less degree on the alkalies. 4. Surfactants, in particular cationic a quartenary ammonium salt, increased yield of 1,2,4-trichlorobenzene from technical BHC by alkaline hydrolysis. 5. Conversion of 1,2,4-trichlorobenzene to 2,4,5-trichloronitrobenzene was effected almost quantitatively utilizing $HNO_3-H_2SO_4$ nitrating agent at low temperature. 6. Yield of 91.4% was observed for the synthesis of 2,4,5-trichloroaniline by reducing 2,4,5-trichloronitrobenzene in the presence of iron turning and hydrochloric acid. 7. Overall yield based on BHC of 3-(2,4,5-trichlorophenyl)-1- methyl urea was 60.8%. 8. Inhibition effects, both germination and growth, 3-(2,4,5-trichlorophenyl)-1-methyl urea on several crops were found comparable to or more potent than those of $linuron{\circledR}\;and\;diuron{\circledR}$. In addition, it was also noted that susceptibility to the prepared compound depended upon the crops as well as specific part (shoots, roots) of the plant exposed to the chemicals.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.57-67
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• 2020

Pinus densiflora is the most widely distributed tree species in South Korea. Its ecological and socio-cultural attributes makes it one of the most important tree species in S. Korea. In recent times however, the distribution of P. densiflora has been affected by dieback. This phenomenon has largely been attributed to climate change. This study was conducted to investigate the responses of growth and physiology of P. densiflora to drought and nitrogen fertiliz ation according to the RCP 8.5 scenario. A Temperature Gradient Chamber (TGC) and CO₂. Temperature Gradient Chamber (CTGC) were used to simulate climate change conditions. The treatments were established with temperature (control versus +3 and +5℃; aCeT) and CO₂ (control: aCaT versus x1.6 and x2.2; eCeT), watering(control versus drought), fertilization(control versus fertilized). Net photosynthesis (P_n), stomatal conductance (g_s), biomass and relative soil volumetric water content (VWC) were measured to examine physiological responses and growth. Relative soil VWC in aCeT significantly decreased after the onset of drought. P_n and g_s in both aCeT and eCeT with fertiliz ation were high before drought but decreased rapidly after 7 days under drought because nitrogen fertilization effect did not last long. The fastest mortality was 46 days in aCeT and the longest survival was 56 days in eCeT after the onset of drought. Total and partial biomass (leaf, stem and root) in both aCeT and eCeT with fertiliz ation were significantly high, but significantly low in aCeT. The results of the study are helpful in addressing P. densiflora vulnerability to climate change by highlighting physiological responses related to carbon allocation under differing simulated environmental stressors.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.86-99
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• 2016

This study was for analyzing the external environment and internal space structure and improving the way of use efficiency in waterfront through the Dragon boat festival to utilize waterfront actively. Through from the four target area, Hongkong, Busan, Incheon and Daejeon, this study was for an importance and satisfaction analysis for users about the element effect on the waterfront use efficiency and the contribution to cultural contents revitalization of waterfront by giving basic data. The result is as follows. First, in the importance analysis about 12 items, modern cultural infra around the waterfront was ranked highest, 8.26 and waterfront landscape, square & openspaces, convenience facilities, transport, green area, quality of viewing space, historic resources, pedestrian, suitability of width, wave, depth, water quality, berth & mooring were ranked in descending order. Second, waterfront landscape was interpreted by rather the external environmental impact according to city size than the matter of spatial structure in target area and judged as an important factor effect on site selection for waterfront. In the analysis of waterfront landscape, the reason of the high satisfaction about domestic target area was that riverside parks were recently made considering their waterfront activities. Viewing space was major infra where people could experience the pleasant waterfront and watch dynamic water leisure sports like Dragon boat three dimensionally and was thought to be improved for the use efficiency. Third, tourism resources were very important element that affect the use efficiency of waterfront, so waterfront users react sensitively to modern tourism resources rather than to historic resources. This meant that tourism infrastructure for shopping and leisure of the young affected the use efficiency of waterfront, so Hongkong and Busan were in a better position in terms of using waterfront that was near the tourism infrastructure. Fourth, in the analysis of traffic accessibility, both Hongkong and Busan were high evaluated in terms of excellent traffic accessibility by subway. Daejeon was low rated in terms of the satisfaction of use efficiency, because of the relative lower place awareness compared with transportation infrastructure. In Hongkong, waterfront was connected with downtown and in Busan, housing complex and shopping centers were located in the place for users in an easily accessible on foot, so the satisfaction was high-pitched. Finally, in the importance of water surface width and the analysis of satisfaction, except Incheon, all the three were over 200m in width of water surface and this meant the surface width above certain level was interpreted to interrupt the concentration of enjoying the water leisure sports. In the analysis of surface condition such as water quality, water depth and wave, through a survey, Busan had a problem with water quality and Gapcheon in Daejeon had a problem with optimal water depth by the festival participants.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.447-453
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• 2001

Background: Although pulmonary resection is the standard approach for the management of pulmonary metastases from soft tissue sarcoma, most of them are unresectable and chemotherapy remains the only option. The effectiveness of the cytotoxic drugs may be limited by the toxicities that occur before the therapeutic dose is reached. The regional administration of doxorubicin using pulmonary arterial perfusion in a rodent model can produce 10 to 25 times higher concentrations in the lung than systemic administration with minimal systemic toxicities. However, it is unclear whether a high concentration of doxorubicin has beneficial effects for killing cancer cells. Material and Method: We studied this to evaluate the dose-dependent cytotoxic and apoptotic effects of doxorubicin on methylcholanthrene-induced rat fibrosarcoma(MCA) cells. This study examined the cytotoxicity and apoptosis-related gene expressions(Fas, FasL, Bax, caspase 1, caspase 2, caspase 8, Bcl-2, Bcl-xL, Bcl-xS) in MCA cells after 24 hours exposure to various concentrations of doxorubicin such as 1, 5, 10, 50, and 100 $\mu$M. Result: Dose-dependent cytotoxicity was observed after 24 hours exposure to doxorubicin. However, peak apoptosis after 24 hours exposure was observed at 5 $\mu$M of doxorubicin. Above 5 $\mu$M, apoptotic activity was decreased with dose-increment. All mRNA levels of apoptosis-related genes after 24 hours exposure were up-regulated above the control level at 1 $\mu$M of doxorubicin and then decreased by doxorubicin dose-increment except caspase 8, which showed higher levels than the control level at 5 $\mu$M. Apoptosis-related protein levels were highest at 1 $\mu$M of doxorubicin and then decreased by doxorubicin dose-increment. However, Bax and Bcl-xL proteins steadily showed higher levels than the control throughout the different concentrations of doxorubicin. Conclusion: These results suggest that apoptosis is the main cytotoxic mechanism in low concentrations of doxorubicin in MCA cells and apoptosis-related genes, such as Bax, caspase 8, and Bcl-xL, are involved. At high concentrations, doxorubicin still can kill MCA cells, even when apoptosis is inhibited, and have its propriety for achieving much cytotoxicity against MCA cells.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.115-127
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• 1973

Leaf discoloration of IR667 lines (tropical) and leading locals (temperate) in fields was classified according to the probable causes and nutritional disorder due to soil reduction in 1972 was investigated. 1. The causes of leaf discoloration in IR667 were low air temperature, soil reduction, seed born, insect bite, nitrogen depression, overdose pesticide, strong wind, early senescence and unknown one. 2. Leaf discoloration due to soil reduction which has been called Sageumbyeong by famers, was caused by the heavy application of $Ca(OH)_2$, compost and poor drainage followed by Zn and K deficiency and Fe toxicity. 3. About 30 days after transplanting deficiency concentration of K and Zn in leaf blade appears to be less than 2.0% and 20ppm respectively, and greater than 200ppm, 500ppm, and 1.0% respectively for toxicity or excess of Fe, Mn and Ca. and in the shoot 2.4% for K, 30ppm for Zn and 800ppm for Fe. The value of K/Ca should be greaterthan 2.0 for health. 4. When plants were damaged by soil reduction the contents of N, P, Ca, Mg, Fe, Mn, Na in shoot were increased and those of K, Zn, Si were decreased. 5. IR667 lines show in shoot higher content of N, P, Ca, Mg, Si, Na, and lower content K, Zn, Fe, Mn and lower root activity than local leading varietles in either healthy or disieased case, indicating IR667 lines are likely more suseptible to soil reduction damage. 6. Normal soil was less than 6.5 of pH and greater than -50 mv of Eh, but pH of problem soil was ranged from 6.7 to 7.4 and Eh from -100 to -190. 7. The root activity (${\alpha}$-naphthylamine oxidation) decreased at early stage of soil redudtion damage, then increased with severity and at the end it decreased again, but IR667 lines showed always lower root activity than local ones.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.1
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• pp.3-15
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• 1997

Iron oxide compounds in 8 selected Cheju Island soil samples have been analized by X-ray fluorescence spectrometer(XRF), X-ray diffractometry(XRD), selected chemical techniques, and $M{\ddot{o}}ssbauer$ spectroscopy. The result of this analysis by XRF shows that the rate of quantity of $Fe_2O_3$ in 8 soil samples was from 8.03wt.%(Daejeong paddy soil) to 18.21wt.%(Songag soils). Songag, Heugag and Gueom soils were detected to have lower peaks of intensity of hematite by XRD. In addition, these soils were not detected to have hematite and goethite peaks. Ferrihydrite, which is a short-range-order mineral commonly present in volcanic ash soil, was not detected by XRD due to low concentration and/or poor cristallinity. Ferrihydrite contents estimated from Feo values were 8.8~35.2g/kg for volcanic ash soils and 0.85g/kg for the Daejeong soil. Most of the soil samples represented by the paramagnetic $Fe^{3+}$ doublet obtained from $M{\ddot{o}}ssbauer$ spectra at room temperature and 18K were considered to arise from the presence of ferrihydrite, superparamagnetic goethite, and silicate minerals. Also the paramagnetic $Fe^{2+}$ doublets are attributable to primary minerals such as olivine, illite, chlorite, augite, biotite, and hornblende. Goethite and hematite were identified as the dominant crystalline iron oxides in these soils from $M{\ddot{o}}ssbauer$ spectra obtained at room temperature and 18K. All the soil samples exhibited strong superparamagnetic relaxation. Collapse of the $M{\ddot{o}}ssbauer$ magnetic hyperfine splitting at room temperature was due to the small size(${\sim}180{\AA}$) of the oxide particles and/or Al-subsituted goethite.