• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.403-410
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• 2009

This study was conducted to investigate the hygienic quality of commercial Kwamegi, a Korean traditional food, made from semi-dried Pacific saury. The hygienic qualities of 10 Kwamegi samples were examined from the 15 commercially available types. Samples with code 3, 4, 6, 11 and 12 were acceptable based on criteria suggested by Ministry for Food, Agriculture, Forestry and Fisheries (i.e. moisture below 50%, total mercury below 0.5 ppm, lead below 2.0 ppm, viable cells below $1.0{\times}10^5$ CFU/g and coliform count below $1.0{\times}10^3$ MPN/100g. Peroxide value of commercial Kwamegi ranged from 15.3-104.1 meq/kg. Agmatine sulfate, cadaverine, histamine, tyramine, spermidine, dopamine and spermine were found in all of the 15 commercially available Kwamegi, while tryptamine and 2-phenylethylamine were not detected. Putrescine dihydrochloride was only detected in 7 samples. The histamine content of commercial Kwamegi ranged from 33-124mg/kg, which is believed to be an acceptable limit according to guidelines from other countries. Cadaverine can be used as a potential index for freshness of commercial Kwamegi as there is a good correlation between volatile basic nitrogen and biogenic amine contents.

• Journal of Environmental Science International
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• v.5 no.6
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• pp.739-748
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• 1996

This study was carried out to investigate the chemical characteristics ol rainwater sampled in Cheju City from July 1994 to June 1996. Concentrations of major ions (Cl-,$SO_4^{2-}$, NO_3^-$, $Na^+$, $K^+$, Ca^{2+}$, $Mg^{2+}$ and NH_4^+$) were determined. The pH of rainwater, calculated from the volume weighted H+ concentration, was found to be 5.61, indicating extensive neutralization of the acidity in the rain. The relative magnitude of average ionic concentrations followed the relation Cl-> $SO_4^{2-}$) $Na^+$> Ca^{2+}$> NH_4^+$> NO_3^-$> $Mg^{2+}$> $K^+$. The ions associated with sea salt, namely $Na^+$ and $Cl^-$, dominated the total concentration of ions in the rainwater and the $SO_4^{2-}$ ion accounts for 20% of total concentration. [H+][nss-SO42-+NO3] ratio and a multiple regression for $SO_4^{2-}$ and NO3- ions against $H^+$, $Ca^{2+}$ and $NH_4^+$ suggested that all of $SO_4^{2-}$ and $NO_3^-$ in rainwater was not necessarily associated with $H_2SO_4$ and $HNO_3$, but might also occur in combination with $NH_4^+$ or Ca^{2+}$. The monthly mean concentrations of $SO_4^{2-}$-, Ca^{2+}$ and $NH_4^+$ in spring time was higher than those in other seasons. These results may De attributed to the fertilizer application as the local sources and the yellow sand phenomina as a regional-scale sources.

• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.162-169
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• 2012

Our country set the mid-term reduction goal of greenhouse gases up to 2020 in accordance with Bali roadmap agreed in 2007 through the negotiation with UNFCCC in 2009 and specified the proper goal as by the Basic Act on Green Growth that went into effect at April, 2010. First of all the enlargement of green building construction has been suggested as a worldwide strategy to achieve the green house gas reduction. Building area is one of most important sectors for the countermeasure of climate change agreement and the achievement of national green house gas reduction goal and the need to reduce its green house gases has been increased accordingly. The objective of the study is to examine the status and characterization of mass energy consumption local governmental buildings' green house gas emissions depending on usage (hotel, school, apartment, hospital) through the green house gas emission source unit analysis. The result indicated that the energy source unit was proportional to green house gas source unit and hotel showed the highest green house gas emission source unit per open area of construction unit, followed by hospital, apartment, and then school. In case of apartment, green house gas emission source unit per open area of construction unit decreased as year went on. Meanwhile school building showed a striking increase in the annual energy source unit.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.958-967
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• 2006

The overall objective of this research was to find out the role of rapid mixing conditions in the species of hydrolyzed Al(III) formed by Al(III) coagulants and to evaluate the distribution of hydrolyzed Al(III) species by coagulant dose and coagulation pH. When an Al(III) salt was added to water, monomers, polymers and solid precipitates may form. Different Al(III) coagulants (alum and PSOM) show to have different Al(III) species distribution over a rapid mixing condition. During the rapid mixing period, for alum, formation of dissolved AI(III) (monomer and polymer) increases, but for PSOM, precipitates of $Al(OH)_{3(S)}$ increases rapidly. During the rapid mixing period, for high coagulant dose, Al-ferron reaction increases rapidly. The kinetic constants, Ka and Kb, derived from AI-ferron reaction. The kinetic constants followed very well the defined tendencies for coagulation condition. For pure water, when the rapid mixing time increased, the kinetic constants, Ka and Kb showed lower values. Also, for raw water, when the rapid mixing time increased, the kinetic constants, Ka and Kb showed lower values. At A/D(Adsorption and Destabilization) and sweep condition, both $Al(OH)_{3(S)}$ and dissolved Al(III) (monomer and polymer) exist, concurrent reactions by both mechanism appear to cause simultaneous precipitation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.2
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• pp.230-239
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• 2018

Objective: The purpose of this study is to identify the kinds and exposure levels of health hazards in the metalworking process in relation to acute poisoning accidents caused by methanol in 2016. Methods: The number of industries, workplaces, exposed workers, regional distribution, and exposure level of health hazards in metalworking process were investigated based on employee exposure assessment database provided by KOSHA (the Korea Occupational Safety and Health Agency), which was collected from workplace hazard evaluation programs in Korea. Exposure metrics for methanol were assessed by RCR (risk characterization ratio). Results: The numbers of processes, workplaces, and exposed workers of metalworking, which include CNC (computer numerical control) were 25, 14,405, and 169,102 respectively. The numbers of samples of chemical hazards including methanol were 91,325, and it was found that workers in metalworking were exposed to 249 kinds of chemical hazards. There were 16 kinds of special controlled substances including beryllium. It is estimated that the number of workplaces involving CNC process was 2,537, and the number of exposed workers was 27,976. In CNC process, the total number of workplaces handling methanol was 36, and 298 workers were estimated to be exposed. There was no exceeded that surpassed the OEL and 49% of samples were below the limit of detection. Methanol exposure concentrations in Gyeonggido Province were statistically significantly higher than in other areas (p <0.0001). Conclusions: In the metalworking process including CNC, there is exposure to a wide variety of health hazards. There was no sample exceeding the OEL for methanol. Therefore, it is necessary to recognize the limits of the employee exposure assessment system and urgently improve measures to prevent the occurrence of events like methanol poisoning.

• Carbon letters
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• v.11 no.1
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• pp.28-33
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• 2010

In this study, $TiO_2$-Activated carbon (AC) complex fibers were prepared by electrospinning for the synergetic effect of adsorption and degradation of organic pollutant. The average diameter of these fibers increased with increasing the amount of AC added, except for 1AC-TOF (AC$/TiO_2$ =1/40 mass ratio). After calcinations at $500^{\circ}C$, long as-spun fibers were broken and their average diameter was slightly decreased. The resultant fibers after calcination had rough surface and sphere shapes like a peanut. From XRD results, it was confirmed that as-spun fibers were changed to anatase $Ti_O2$ fiber after calcinations at $500^{\circ}C$. The prepared $TiO_2$-AC complex fibers could remove procian blue dyes by solar light irradiation with high removal property of 94~99%. The PB dye was rapidly removed by adsorption during the initial 5 minutes. But after 5 minutes, dye removal was occurred by photodegradation. In this study, the most efficient AC/$TiO_2$ ratio of $TiO_2$-AC complex fibers was 5/40, showing the synergetic effect of adsorption and photodegradation. It is expected that the $TiO_2$-AC complex fibers can be used to remove of organic pollutants in water system.

• BMB Reports
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• v.37 no.2
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• pp.153-158
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• 2004

The acid-labile subunit (ALS) is known to interact with the IGF binding protein (IGFBP) in the presence of insulin-like growth factors (IGFs). Studies, however, indicate that ALS forms a doublet with IGFBP3, independent of IGFs. To characterize the structural domain required for the IGF-free ALS-IGFBP3 interaction, seven recombinant human IGFBP3 mutants were generated: three deletion mutants and four site-specific mutants that had altering N-terminal regions of IGFBP3. ALS and IGFBP3 mRNAs were co-injected into Xenopus oocytes, and their products were cross-linked and immunoprecipitated using antisera against ALS or IGFBP3. Among the deletion mutants, the mutant of D40 (deleted in 11-40th amino acids) exerted no effect in the interaction with ALS, while D60 (${\Delta}11$-60) demonstrated a moderate reduction. D88 (${\Delta}11$-88), however, showed a significant decrease. In the case of site-specific mutants, the mutation that alterated the IGF binding site (codons 56 or 80) exerted a significant reduction in the interaction, whereas codons 72 or 87 showed no significant change in the interaction with ALS. The stability of the ALS-IGFBP3 interaction was analyzed according to a time-dependent mode. Consistent with the binding study, mutants on the IGF binding sites (56 or 80) consistently show a weakness in the ALS-IGFBP3 interaction when compared to the mutants that covered the non-IGF binding sites (72 or 87). This study suggests that the N-terminal of IGFBP3, especially the IGF binding site, plays an important role in interacting with ALS as well as in stabilizing the dual complex, independent of IGFs.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.161-168
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• 1995

Brain dopamine systems play a central role in the control of movement, hormone release, and many complex behavior. The action of dopamine at its synapse is terminated predominately by high affinity reuptake into presynaptic terminals by dopamine transporter (DAT). The dopamine transporter(DAT) is membrane protein localized to dopamine-containing nerve terminals and closely related with cocaine abuse, Parkinsonism, and schizophrenia. In present study, the recombinant plasmid pRc/CMV-DAT, constructed by subcloning of a cDNA encoding a bovine DAT into eukaryotic expression vector pRc/CMV, was stably transfected into CV-1 cells(monkey kidney cell line). The DAT activities in the cell lines selected by Geneticin$^{R}$ were determined by measuring the uptake of $[^3H]$-dopamine. The transfected cell lines showed 30-50 fold higher activities than untransfected CV-1 cell line, and this result implies that DAT is well expressed and localized in transfected cells. The transfected cells accumulated $[^3H]$-dopamine in a dose-dependent manner with a $K_{m}$ of 991.6nM. Even though high doses of norepinephrine, epinephrine, serotonin, and choline neurotransmitters inhibited the uptake of $[^3H]$-dopamine, DAT in transfected cell line was proven to be much more specific to dopamine. The psychotropic drugs such as GBR12909, CFT, normifensine, clomipramine, desipramine, and imipramine inhibited significantly the dopamine uptake in tissue culture cells stably transfected with DAT cDNA. Radioactive in situ hybridization was done to map the cellular localization of DAT mRNA-containing cells in the adult rat central nervous system. The strong hybridization signals were detected only in the substantia nigra pars compacta and ventral tegmental area. The restricted anatomical localization of DAT mRNA-containing cells confirms the DAT as a presynaptic marker of dopamine-containing cells in the rat brain.

• Animal cells and systems
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• v.15 no.1
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• pp.37-43
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• 2011

The Korean freshwater crayfish, Cambaroides similis, has recently suffered from range reduction and habitat degradation caused by environmental changes and water pollution. For the conservation and restoration of this species, it is necessary to understand the current population structures of Korean C. similis using estimation of their genetic variation. In this study, eight micro satellite loci were developed and characterized from 49 individuals collected from four locations: one population from Mt. Bukhan (BH) and three populations from Mt. Gwanak (GA) in Seoul, Korea. As a result, the number of alleles per locus ranged from 2 to 12. The observed heterozygosities and expected heterozygosities ranged from 0.000 to 0.833 and from 0.125 to 0.943, respectively, and the former values were significantly lower than the latter ones expected under the Hardy-Weinberg equilibrium. No significant linkage disequilibrium was revealed between any of the locus pairs after Bonferroni correction. From the pairwise Fst results over all samples, higher differentiation between GA-BH population pairs (mean 0.1789) was observed than between GA population pairs (mean 0.0454). This was also supported by Mantel's test showing that the genetic distances of these crayfish populations were significantly correlated with geographic distances. This result may show the regional differentiation caused by restricted gene flow between northern (BH) and southern (GA) populations within Seoul. These micro satellite markers have the potential for use in analyses of the genetic diversity and population structure of C. similis species, with implications for its conservation and management plans.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.9
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• pp.261-268
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• 2016

One of the most comfortable transportation in our day to day life is the bus, which provides real time information. In order to obtain reliable information on the arrival time of this information, BIS (Bus Information System) needs to analyse the main factor for the traffic environment. To manage the system, regional information analysis by local municipalities should be prioritized. In this paper, we analyse the features that are expected to affect traffic environment by commuting the travel to school, market, tourism and other influences around Suncheon-si, which has the facilities for education, tourism and urban locality. Data cleaning is performed on the DB information that is being collected from characterization BIS, which is organized by day of the week, day and month, to analyse the key factors of the traffic flow. If this is utilized by applying a key factor to the real time information, it is expected to provide more reliable and accurate information.