• Parasites, Hosts and Diseases
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• v.34 no.3
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• pp.197-206
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• 1996

Water extract of Coix locrvmn seeds (Co-Ex) was separated into several components; dissolved with Tris-Cl buffer and the supernatant (WC 1), ammonium sulfate treatment supernatant (WC2) and the pellet nvc31,9AE column chromatography of WC 1 and the peak portions; WC4, WCS and WC6. Murine peritoneal macrophages in DMEM containing 10% heat-inactivated FCS were infected with tachyzoites of ToxopIQsmc gondii, RH strain, in uifo. By adding modulators such as Co-Ex, WC 1,2,3,4.5,6 and LPS or IFN-γ for 24 hrs . toxoplasmastatic activity of macrophages was examined in relation to nitrite production. Nitrite production of macrophages was enhanced especially in the series of WC2, WC1 and the combination sample (WC1 + WC2 + WC3) by order than other components or fractions (WC4, WC5, WC6) tested . Toxoplasmastatic actions such as percentage of the inacrophages infected by T. gonnii and fold increase of T gondii in macrophages showed retroverse relations with the amount of nitrite production; i.e. as nitric oxide (NO) increased the phagocytic index of macrophages and the fold increase of tachyzoites in macrophages decreased . Nitrite (NO-2) production was increased by adding IFN-γ in all cases together with enhancement of biostatic effects. Through the results obtained, it is speculated that some components other than the non-proteinous and defatted components in Coix lacrwmn seeds may contribute to activate macrophages through induction of NO for the biostatic activity.

• Korean Journal of Ecology and Environment
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• v.34 no.1 s.93
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• pp.30-44
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• 2001

In this study limnological characteristics of Lake Juam was surveyed from June 1993 to May 1994 in order to provides important information regarding water resources. Secchi disc transparency, epilimnetic chlorophyll a (chi-a), total nitrogen (TN), total phosphorus (TP) concentration and primary productivity were in the range of $2.0{\sim}4.5\;m$, $0.9{\sim}13.6\;mgChl/m^3$, 0.78$\{sim}$2.32 mgN/l, $11{\sim}56\;mgP/m^3$, $270{\sim}2.160\;mgCm^{-2}\;day^{-1}$, respectively. On the basis of TP, Chl-a and Secchi disc depth, the trophic state of Lake Juam can be classied as mesotrophic lake. The phosphorus inputs from non-point sources are concentrated in heavy rain episodes during the monsoon season. As a result, phosphorus concentration are higher in summer than in winter. TP loading from the watershed were estimated to be $0.9\;gPm^{-2}yr^{-1}$, which correspond to a boundary of the critical loading ($1.0\;gPm^{-2}yr^{-1}$) for eutrophication. From the results of the algal assay, both phosphous and nitrogen act as limiting nutrients in algal growth. The seasonal succession of phytoplankton community structure in Lake Juam was similar to that observed in other temperate lakes. Diatoms (Asterionella formosa and Aulacoseira granulate var. angustissima)fujacofeira BraHuJafa uar. aHgusHrsiaia) weredominant in spring and winter, cyanobacteria) were dominant in warm season. The organic carbon, nitrogen and phosphorus content of lake sediment were $9.5{\sim}14.0\;mgC/g$, $1.01{\sim}1.82\;mgN/g$ and $0.51{\sim}0.65\;mgP/g$, respectively. The allochthonous organic carbon loading from the watershed and autochthonous organic carbon loading by primary production of phytoplankton were determined to be 1,122 tC/yr and 6,718 tC/yr, respectively. To prevent eutrophication of Lake Juam, nutrient management of watershed should be focus on reduction of fertilizer application, proper treatment of manure, and conservation of topsoil as well as point source.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.1
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• pp.1-13
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• 2011

The aim of this study was to evaluate shear bond strength of pressed reinforced composite resin ($TESCERA^{TM}$ ATL) veneering to zirconia with various surface treatments. Forty sintered zirconia specimens and forty pockmarked zirconia specimens were fabricated. All the materials were categorized as Group 1 (Control : porcelain veneering on zirconia surface), Group 2 ( $TESCERA^{TM}$ ATL dentine veneering after bonding agent application on zirconia surface), Group 3 ($TESCERA^{TM}$ ATL dentine veneering on pockmarked zirconia surface), Group 4 ($TESCERA^{TM}$ ATL dentine veneering after bonding agent application on pockmarked zirconia surface), Group 5 (Thermocycling on Group 1), Group 6 (Thermocycling on Group 2), Group 7 (Thermocycling on Group 3), and Group 8 (Thermocycling on Group 4). SBS(Shear bond strength) of 8 groups was determined with an Instron Universal Testing Machine. Also fractured surface of specimens were observed with a scanning electron microscope. There were no significant differences in the initial SBS between Group 1(control group), Group 3, and Group 4. (p>0.05) Group 2 presented the lowest SBS values. There was a no significant difference between just as 24hour water storage and simulated aging on pockmarked zirconia groups. (p>0.05) A formation of pockmarked irregularities on zirconia surface as mechanically pitted surface was reliable method for establishing a stronger bond between $TESCERA^{TM}$ ATL and zirconia-based material.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.331-340
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• 2000

The existing two-phase biological fluidized bed has some problems such as limit of oxygen transfer and blockade of fluidized distributor. In this study, three-phase swirl flow biological fluidized bed has designed to solve the problems and to investigate its running characteristics. TOC of influent synthetic wastewater was approximately $70mg/{\ell}$. HRT of reactor was 1.6 hours. Mean particle size of sand, as packing media, was 0.397mm and packing volume was varied from $200m{\ell}/{\ell}$ to $600m{\ell}/{\ell}$ by stages in the bed. The amount of biomass and effluent water quality was throughly investigated in the bed. Showing experiment results from the above conditions, it was possible to solve the problems of existing fluidized bed and to keep DO of $3mg/{\ell}$ or more. And it was also TOC removal rate of 91 to 94 %, MLVSS of 2,360 to $3,860mg/{\ell}$, MLVSS per g-media of 8.4 to 17.3 mg/g, F/M ratio of 0.59 to $1.04kg-TOC/kg-MLVSS{\cdot}day$, biofilm thickness of $35{\sim}71{\mu}m$ and sludge productivity of 1.03 to $2.35kg-SS/m^3{\cdot}day$. Optimal conditions in this experimental were as follows.; those were biofilm thickness of approximately $54{\mu}m$. MLVSS per g-media of 13 mg and media packing volume of 350 to $400m{\ell}/{\ell}$ when F/M ratio was low, treatment efficiency was high and sludge productivity was low. Showing the media with optics microscope in this optimal condition, attached microbes such as Epistylis sp. were observed. From SEM photographs, it showed that Coccus adhere to and grow on the media surface.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.137-145
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• 2013

This study was performed at 2 sites of Nak-Dong River to investigate the changes of nitrifiers depending on the presence and absence of organic pollutants (due to the effluents of domestic wastewater treatment plant, WWTP). Conventional chemical parameters such as T-N, $NH_4$-N, $NO_2$-N, $NO_3$-N were measured and the quantitative nitrifiers at the 2 sites were analyzed comparatively by fluorescent in situ hybridization (FISH) with NSO190 and NIT3, after checking the presence of gene amoA of ammonia oxidizing bacteria (AOB) and 16S rDNA signature sequence for Nitrobacter sp. that belongs to nitrite oxidizing bacteria (NOB). Also ${\alpha}{\cdot}{\beta}{\cdot}{\gamma}$-Proteobacteria were detected using FISH to get a glimpse of the general bacterial community structure of the sites. Based on the distribution structure of the ${\alpha}{\cdot}{\beta}{\cdot}{\gamma}$-Proteobacteria and the measurement of nitrogen in different phases, it could be said that the site 2 was more polluted with organics than site 1. Corresponding to the above conclusion, the average numbers of AOB and NOB detected by NSO160 and NIT3, respectively, at site 2 [AOB, $9.3{\times}10^5$; NOB, $1.6{\times}10^6$ (cells/ml)] was more than those at site 1 [AOB, $7.8{\times}10^5$; NOB, $0.8{\times}10^6$ (cells/ml)] and also their ratios to total counts were higher at site 2 (AOB, 27%; NOB, 34%) than those at site 1 (AOB, 18%; NOB, 23%). Thus, it could be concluded that the nitrification at site 2 was more active due to continuous loading of organics from the effluents of domestic WWTP, compared to site 1 located closed to raw drinking water supply and subsequently less polluted with organics.

• Journal of Environmental Impact Assessment
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• v.4 no.3
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• pp.41-48
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• 1995

In former times the protection of our environment didn't play an important role due to the fact that emissions and effluents were not considered as serious impacts. However, opinions and scientific measurements meanwhile confirmed that the impacts are more serious than expected. Thus measures to protect our earth has to be taken into consideration. A part of these measures in the Environmental Impact Assessment (EIA). One of the most important parts of the EIA is the collection of basic datas and the following evaluation. Experience out of the daily business of Gerling Consulting Group shows that the content of the EIA has to be revised and enlarged in certain fields. The historical development demonstrated that in areas in which the population and the industrial activities reached high concentration there is a high necessity to develop strict environmental laws and regulations. Maximum values of the concentration of hazardous materials were fixed concerning the emission into and water. Companies not following these regulations were punished. The total amount of environmental offences increased rapidly during the last decade, at least in Germany. During this development the public consciousness concerning environmental affairs increased as well in the industrialized countries. But it could clearly be seen that the development in the field of environmental protection went into the wrong direction. The technologies to protect the environment became more and more sophisticated and terms as: "state of the art" guided more and more to lower emissions, Filtertechnologies and wastewater treatment for example reached a high technical level-but all these sophisticated technologies has one and the same characteristic: they were end-of-the pipe solutions. A second effect was that this kind of environmental protection costs a lot of money. High investments are necessary to reduce the dust emission by another ppm! Could this be the correct way? In Germany the discussion started that the environmental laws reduce the attractivity to invest or to enlarge existing investments within the country. Other countries seem to be not so strict with controlling the environmental laws which means it's simply cheaper to produce in Portugal or Greece. Everybody however knows that this is not the correct way and does not solve the environmental problems. Meanwhile the general picture changes a little bit and we think it changes into the correct direction "End-of-the-pipe" solutions are still necessary but this word received a real negative touch and nobody wants to be brought into connection with this word received a real negative touch and nobody wants to be brought into connection with this word especially in connection with environmental management and safety. Modern actual environmental management starts in a different way. Thoughts about emissions start in the very beginning of the production, they start with the design of the product and modification of traditional modes of production. Basis of these ideas are detailed analyses of products and processes. Due to the above mentioned facts that the public environmental consciousness changed dramatically a continous environmental improvement of each single production plant has to be guarantied. This question is already an important question of the EIA. But it was never really checked in a wholistic approach. Environmental risks have to be taken into considerations during the execution of an EIA. This means that the environmental risks have to be reduced down to a capable risk-level. Environmental risks have to be considered within the phase of planning, during the operation of a plant and after shut down. The experience shows that most of the environmental relevant accidents were and caused by human fault. Even in highly protected plants the human risk-factor can not be excluded during evaluation of the risk-potential. Thus the approach of an EIA has to regard technical evaluations as well as organizational thoughts and the human factor. An environmental risk is a threat to the environment. An analysis of the risk concerning the organizational and human aspect however never was properly executed during an EIA. A possible solution could be to use an instrument as the actual EMAS (Environmental Management System) of the EC for more accurate evaluation of the impact to the environment during an EIA. Organizations or investors could demonstrate by an approved EMAS or even by showing their installment of EMAS that not only the technical level of the planned investment meets the requested standards but as well the actual or planned management is able to reduce the environmental impact down to a bearable level.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.2
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• pp.47-56
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• 2008

The objective of this research is to evaluate the optimum recycling methods for the sewage sludge cakes at different microwave power-settings and for different periods of time. The dehydrated sewage sludge cakes used in this study was obtained from N wastewater treatment plan in the P City. The beginning drying processes were carried out in a microwave oven with 2,450 MHz frequency and power ranges of 1kW to 4 kW. The continuous conveyer drying system was also operated with 2,450 MHz frequency and power setting, ranging from of 1 kW to 6 kW. Initial moisture content of the sewage cake is 78~80%, and the moisture content decreased rapidly up to 0.2~2(wt%) within short periods due to breaking the cell walls. This study is also conducted to evaluate the characteristics of sewage sludge cakes with respect to important physical parameters effect on the thermal kinetics for evaporation water in the sludge which are operation times, moisture contents, drying rates, input amounts, flow rates and calorific values. It takes 60 minutes and 120 minutes to reach the critical moisture contents with power setting of 4 kW for 3kg/min and 6kg/min of the flow rates respectively. It takes 120 minutes and 110 minutes to reach the critical moisture contents with flow rates of 2.5 cm/min and sludge input of 6kg/min for the power settings of 4 kW and 6 kW respectively. The most effective value of the power for drying the sludge is 4 kW. Operation with 6kg/min and 4kW on 2cm of the sludge thickness can be effectively and inexpensively to reach the critical moisture contents, when you compare 2cm of the sludge thickness with 1cm and 3cm of the sludge thickness.

• Progress in Medical Physics
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• v.22 no.4
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• pp.190-197
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• 2011

Currently, the dose distribution calculation used by commercial treatment planning systems (TPSs) for high-dose rate (HDR) brachytherapy is derived from point and line source approximation method recommended by AAPM Task Group 43 (TG-43). However, the study of Monte Carlo (MC) simulation is required in order to assess the accuracy of dose calculation around three-dimensional Ir-192 source. In this study, geometry factor was calculated using segmented sources integration method by dividing microSelectron HDR Ir-192 source into smaller parts. The Monte Carlo code (MCNPX 2.5.0) was used to calculate the dose rate $\dot{D}(r,\theta)$ at a point ($r,\theta$) away from a HDR Ir-192 source in spherical water phantom with 30 cm diameter. Finally, anisotropy function and radial dose function were calculated from obtained results. The obtained geometry factor was compared with that calculated from line source approximation. Similarly, obtained anisotropy function and radial dose function were compared with those derived from MCPT results by Williamson. The geometry factor calculated from segmented sources integration method and line source approximation was within 0.2% for $r{\geq}0.5$ cm and 1.33% for r=0.1 cm, respectively. The relative-root mean square error (R-RMSE) of anisotropy function obtained by this study and Williamson was 2.33% for r=0.25 cm and within 1% for r>0.5 cm, respectively. The R-RMSE of radial dose function was 0.46% at radial distance from 0.1 to 14.0 cm. The geometry factor acquired from segmented sources integration method and line source approximation was in good agreement for $r{\geq}0.1$ cm. However, application of segmented sources integration method seems to be valid, since this method using three-dimensional Ir-192 source provides more realistic geometry factor. The anisotropy function and radial dose function estimated from MCNPX in this study and MCPT by Williamson are in good agreement within uncertainty of Monte Carlo codes except at radial distance of r=0.25 cm. It is expected that Monte Carlo code used in this study could be applied to other sources utilized for brachytherapy.

• Food Science and Preservation
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• v.20 no.6
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• pp.760-765
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• 2013

The image analysis as a tool for evaluation of browning degree on fresh-cut lotus root was studied. The fresh-cut lotus root treated as 4 groups (Cont-without any treatment, DB-blanching at $50^{\circ}C$ for 5 min in distilled water, AB-blanching at $45^{\circ}C$ for 5 min in 1% ascorbic acid, CB-blanching at $45^{\circ}C$ for 5 min in 1% citric acid). The samples treated with each methods were packaged with 0.04 mm polyethylene bag ($25cm{\times}30cm$) and stored at $4^{\circ}C$ for 9 days. On the RGB color space, the AB and CB group showed high R, G, B value. On the HSV and CIE $L^*a^*b^*$ color space, the AB and CB group showed low browning area, $a^*$, $b^*$ value and high $L^*$ value. Polyphenol oxidase activity was low in the AB and CB groups in all storage period. This result means that the AB and CB groups were inhibited the development of tissue browning. The result of sensory evaluation also supported this opinion. And the correlation coefficient between sensory evaluation with all color values was over 0.84. Especially, the $L^*$ value showed the highest correlation coefficient (0.93). In conclusion, the image analysis is suitable for analysis of browning degree on fresh-cut lotus root by analyzing diverse color value.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.145-154
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• 2013

Flonicamid was a water-soluble and systemic insecticide. It was applied to control neonicotinod pesticide-resistant cotton aphid in sweet peppers. However, the residue levels of total flonicamid in sweet pepper exported to Japan in 2009 were exceeded the maximum residue limit (MRL). This study was conducted to elucidate residual properties of flonicamid parent compound and its metabolites in sweet peppers. It was carried out to compare the variation of residues in sweet pepper in three different greenhouses for 21 days after 3 times application with 7 days interval. The mean residues were 0.176, 0.152 and 0.108 mg $kg^{-1}$ and the residue levels in sweet pepper among three greenhouses show significant difference. The maximum residue levels were detected 10 days later after last treatments. The overall residue levels were lower than MRL 2.0 mg $kg^{-1}$ (by Korea) and 0.4 mg $kg^{-1}$ (by Japan in 2009 but now revised MRL is 2.0 mg $kg^{-1}$). But the residue level of total flonicamid at the 21th day after 3 times treatment with 7 days interval was 0.429 mg $kg^{-1}$ restricted by the application of double rate than recommended rate. The amounts of metabolites, TFNA, 4-Trifluoro methyl nicotinic acid and TFNG, N-(4-trifluoro methyl nicotinoyl) glycine were increased while flonicamid parent compound was decreased over time. Therefore the longer trial period should be needed for flonicamid in sweet peppers.