• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.89-102
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• 2000

A total of 318 particulate sample sets consisting of both fine PM(FPM : dp$\leq$2.5 ${\mu}{\textrm}{m}$) and coarse PM(CPM : 2.5${\mu}{\textrm}{m}$${\mu}{\textrm}{m}$) was collected by a dichotomous sampler in Suwon area from December 1996 to November 1997. The concentration of seven inorganic elements such as pb. Cr, Cd, Cu, Zn Fe and Na were determined from each sample using an AAS. The purpose of the study was to extensively investigate environmental behaviors of particulate matters and to provide air quality management schemes applying various statistical approaches. The mean concentrations of PM10 Results of correlation analyses indicated the existence of strong correlations among inorganic elements PM10 FPM CPM and various meterological variables. Our study also examined the degree of uncertainties whether the particular elements can be assorted into the accumulation mode or the coarse mode in their size distribution. Furthermore the analysis of the pollution rose showed graphically the direction of potential sources of particulate matters. According to statistical analyses of our data quantitative differences appeared in the pollution patterns between weekdays and weekends.

• Journal of Sensor Science and Technology
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• v.28 no.6
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• pp.355-359
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• 2019

Exosomes, known as nanoscale extracellular vesicles in the range of 30-150 nm, are known to contain clinically significant information. However, there is still insufficient information on exosomal membrane proteins for cancer diagnosis. In this work, we investigated the characteristics of the membrane proteins of exosomes shed by cultured breast cancer cell lines using a surface plasmon resonance (SPR) spectroscopy and pre-activated alkanethiols modified sensor chips. The antibodies of breast cancer biomarkers such as MCU-16, EpCAM, CD24, ErbB2, and CA19-9 were immobilized on the pre-activated alkanethiols surfaces without any activation steps. The purified exosomes were loaded onto each antibody surface. The affinity rank of the antibody surfaces was decided by the relative capture efficiency factors for the exosomes. In addition, an antibody with a relative capture efficiency close to 100% was tested with exosome concentration levels of 10⁴/µl, 10⁵/µl, and 10⁶/µl for quantitative analysis.

• Economic and Environmental Geology
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• v.32 no.3
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• pp.261-271
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• 1999

Mining activity in the Gubong gold mine started in 1908 and lasted up to recent days. Heavy metals derived from the activity may be porentially toxic to human life and envirinment of this area. Because metal toxicity depends on chemical associations into five operationally defined groups: exchangeable, carbonate, reducible, oxidizable, and residual fractions, and the Most of heavy metals have significant little significance (alomost<1%). And Cu is mainly associated with the oxidizable from. Total concentration of heavy metals, pH, and mineralogy affect the chemical forms of the metals. Heavy metal concentrations. Significant amounts of metal elements (5∼65.1% in Pb, 6.2∼39.7% in Zn, 8.7∼54.7% in Cd, and 3.6∼24.7% in Cu) were present in carbonate form from mine wastes, contaminated soils and sediments. High pH value and cerussite (Pb bearing carbonate mineral) in mine wastes, contaminated soils and sediments. High pH value and cerussite (Pb beraring varbonate mineral) in mine waste support this result. Areas with high corbonate bound from would have higher potentoal conamination, however, because elements of carbonate bound forms are easily mobilized under lower pH conditions in the surface envionments due to acid to rain soil acidification.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.768-775
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• 2016

Heavy metal pollution in arable field is an critical problem due to crop safety. For this reason, national survey of heavy metal pollution in the arable field near at the industrial area has been conducted from 1999 in Korea. The main purpose of this research was to monitor heavy metal pollution in Chungnam/chungbuk province and to evaluate pollution index (PI) in soil. Total of 15 sampling locations were examined and average concentration of each heavy metals were following: As - $2.99{\pm}2.63$, Cd - $0.23{\pm}0.07$, Cu - $9.35{\pm}6.48$, Ni - $9.26{\pm}8.03$, Pb - $10.18{\pm}3.32$, Zn - $52.9{\pm}17.18$. No sampling site was exceeded threshold level of each heavy metals. Calculated PI in soil was ranged between 0.03 - 0.27 indicating that also no heavy metal pollution is occurred in examined sampling locations. Although, no heavy metal pollution was observed in the examined sites but monitoring of heavy metal pollution should be continued for possible accidental pollution in arable field near at the industrial area.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.3
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• pp.242-247
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• 1998

In this study, we have synthesized $ZnGa_2O_4$:Mn,X powder doped with Mn, MnO, $MnF_2$ and $MnCl_2$, low voltage green emitting phosphor, in vacuum atmosphere. From PL spectra, the intensity of the emission peak, the brightness with coactivator show that $ZnGa_2O_4$:Mn,Cl > $ZnGa_2O_4$:Mn,F > $ZnGa_2O_4$:Mn,O > $ZnGa_2O_4$:Mn. These improvement of the brightness are caused by the increase of the concentration of $Mn^{2+}$ ion. In case of $ZnGa_2O_4$:Mn,Cl and ZnGa$_2$O$_4$:Mn,F, the brightness is enhanced much more, which is owed to the decrease of defect of host material. For $ZnGa_2O_4$:Mn,Cl phosphor fabricated with optimized condition, the decay time becomes short from 30 ms of the $ZnGa_2O_4$:Mn and $ZnGa_2O_4$:Mn,O to 6 ms and the brightness of CL at 1 kV, 1 mA is 60 cd/$m^2$.

• Transactions on Electrical and Electronic Materials
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• v.11 no.3
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• pp.145-148
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• 2010

White organic light emitting devices were fabricated to improve the stability through a structural change using the two peak emission method. The fabricated devices were composed of indium tin oxide (100 nm)/ $\alpha$-NPD (30 nm)/4,40-bis(2,20-diphenylvinyl)-1,10-biphenyl (DPVBi, d: variable)/DPVBi: Rubrene (40 nm)/2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline(5 nm)/ $Alq_3$(5 nm)/ Al (100 nm). A DPVBi for blue emissions was used as the host material in the emitters. The doping concentration of the Rubrene was fixed at 2.0% (by weight). The white emission with Commission Internationale De L'Eclairage coordinates of (0.3342, 0.3439) occurred at 14 V with a thickness d of 1 nm. It was insensitive to the drive voltage, and the devices had a maximum luminance of $211\;cd/cm^2$. At 19 V, the current density and maximum external quantum efficiency were $173\;mAcm^2$ and 0.478%, respectively.

• Journal of Environmental Health Sciences
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• v.33 no.6
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• pp.502-505
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• 2007

To estimate the soil quality of Miryang area, soil analysis were conducted according to the city and out of city of soil expenses at according to analysis components and heavy metal pollution of irradiation sampling sites. The through soil components the principal element about the 71% $SiO_2\;and\;Al_2O_3$, the pH of field area near the city center was lower than that of the other field area, which indicated that this acidification was probably attributed to the acid rain caused by the traffic exhaust gas such as $SO_x\;and\;NO_x$. Acidification was more severe in the field area than in the farming land. The concentration of five heavy metals such as Cu, Cd, Pb, As and Cr were found to be lower than the standard of soil pollution. An assessment using the SPI(Soil Pollution Index), which was developed to estimate an overall soil quality, was performed. Each SPS(Soil Pollution Score) were evaluated with the results of the data from this study. The soil quality of most area of Miryang land was determined to Class 1, which indicated that the soil was healthy.

• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.95-99
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• 2007

In order to find novel cancer chemopreventive agents, quinone reductase (QR) inductive activity of methanol extract of herbal medicines was examined using murine hepatoma, hepa1c1c7 cells. QR has been used as an anticarcinogenic marker enzyme in cancer chemoprevention study. The methanol extract of Alpinia officinarum (Zingiberace) showed showed significantly strong quinone reductase inductive activity compared to the control group. The methanol extract of Alpinia officinarum was successively fractionated with various solvents according to polarity. Hexane, ethyl acetate, buthanol and water fractions were obtained and theirs activities were assessed. The QR inductive effect was moved to the ethyl acetate fraction and was highly increased. The CD (concentration required to double the specific activity of QR) value of ethyl acetate fraction was 8.6 ${\mu}g/mL$. Alpinia officinarum also showed strong antioxidant activity. These results suggest that Alpinia officinarum can be developed as cancer chemopreventive agent.

• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.77-82
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• 2010

Peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is a ligand-activated transcription factor that is used as a target for anti-diabetic drug development. In a search for novel PPAR${\gamma}$ agonists, the $\beta$-carboxyethyl-rhodanine derivative SP1818 was identified. We report here the characteristics of SP1818 as a selective PPAR${\gamma}$ agonist. In transactivation assays, SP1818 selectively activated PPAR${\gamma}$, but the degree of PPAR${\gamma}$ stimulation was less than with $1{\mu}M$ rosiglitazone. SP1818 also stimulated glucose uptake in a concentration-dependent manner. The adipocyte differentiation markers adiponectin, scavenger receptor CD36 and aP2 were weakly induced by treatment with SP1818, and TRAP220 subunit was specifically recruited into PPAR${\gamma}$ activated by rosiglitazone but not PPAR${\gamma}$ activated by SP1818.

• Journal of Soil and Groundwater Environment
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• v.18 no.4
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• pp.32-39
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• 2013

This research focused on the effects of heavy metals on the biomonitoring activity of genetically engineered bioluminescent bacteria, Pseudomonas putida mt-2 KG1206. KG1206 was exposed to single or binary mixtures of different heavy metals as well as soils contaminated with heavy metals. In case of single exposure with different inducer pollutant, the toxicity order was as followings : As(III) > Cd, As(V) >> Cu, Cr(VI). The toxic effects of the binary mixtures was compared to the expected effect based on a simple theory of probabilities. The interactive effects were mostly additive, while in few cases antgonistic and synergistic mode of action was observed for some concentration combinations. No considerable correlation was found between the total metal contents in soils and the bioluminescence activity of each sample. However, statistically significant differences (p = 0.0102) were observed between two groups, classified based on arsenite contamination. These results demonstrate the usage of recombinant bioluminescent microorganism in biomonitoring and the complex interactive effects of metals.