• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.59-71
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• 2016

To investigate the sorption characteristics of Cs, which is one of the major isotopes of nuclear waste, on natural zeolite chabazite, XRD, EPMA, EC, pH, and ICP analysis were performed to obtain the informations on chemical composition, cation exchange capacity, sorption kinetics and isotherm of chabazite as well as competitive adsorption with other cations ($Li^+$, $Na^+$, $K^+$, $Rb^+$, $Sr^{2+}$). The chabazite used in this experiment has chemical composition of $Ca_{1.15}Na_{0.99}K_{1.20}Mg_{0.01}Ba_{0.16}Al_{4.79}Si_{7.21}O_{24}$ and its Si/Al ratio and cation exchange capacity (CEC) were 1.50 and 238.1 meq/100 g, respectively. Using the adsorption data at different times and concentrations, pseudo-second order and Freundlich isotherm equation were the most adequate ones for kinetic and isotherm models, indicating that there are multi sorption layers with more than two layers, and the sorption capacity was estimated by the derived constant from those equations. We also observed that equivalent molar fractions of Cs exchanged in chabazite were different depending on the ionic species from competitive ion exchange experiment. The selectivity sequence of Cs in chabazite with other cations in solution was in the order of $Na^+$, $Li^+$, $Sr^{2+}$, $K^+$ and $Rb^+$ which seems to be related to the hydrated diameters of those caions. When the exchange equilibrium relationship of Cs with other cations were plotted by Kielland plot, $Sr^{2+}$ showed the highest selectivity followed by $Na^+$, $Li^+$, $K^+$, $Rb^+$ and Cs showed positive values with all cations. Equilibrium constants from Kielland plot, which can explain thermodynamics and reaction kinetics for ionic exchange condition, suggest that chabazite has a higher preference for Cs in pores when it exists with $Sr^{2+}$ in solution, which is supposed to be due to the different hydration diameters of cations. Our rsults show that the high selectivity of Cs on chabazite can be used for the selective exchange of Cs in the water contaminated by radioactive nuclei.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.663-674
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• 2000

A total of 165 independently oriented core samples were collected from 19 Cretaceous Yuchon Group sites in Kosong area, the southernmost part of the Miryang subbasin of the Kyongsang Basin in southern Korea. Stepwise AF and thermal cleaning revealed antipodal ChRM from 95 samples from 14 sites. Mean ChRM direction is d=26.0$^{\circ}$, i=49.4$^{\circ}$ (${\alpha}_{95}$=8.2$^{\circ}$, k=24.5, n= 14) before bedding correction and d=28.1$^{\circ}$, i=54.2$^{\circ}$ (${\alpha}_{95}$=4.8$^{\circ}$, k=70.6, n= 14) after bedding correction. A 2.88-fold increase of the precession parameter k by bedding correction indicates pre-folding age of the ChRM with 99% confidence level. Palaeomagnetic pole position calculated from the mean ChRM is 67.0$^{\circ}$N, 210.6$^{\circ}$E (dp=4.7$^{\circ}$, dm=6.7$^{\circ}$), which is significantly different neither from the poles of other part of the Kyongsang Basin nor those of Eurasia including SCB and NCB. This suggests stable relative position of the study area with regard to other parts of the Kyongsang Basin as well as to Eurasia continent since Cretaceous. Three ploarity reversals in the Kosong Formation in addition to the coexistence of normal and reversed polarities in the overlying Andesites and Welded Tuff suggest, in reference to the worldwide geomagnetic polarity time scale, an Albian to Maastrichtian (polarity chron 32r-31r) age of the Yuchon Group of the study area. An alleged hypothesis of stratigraphical correspondence between the Kosong Formation in the study area and the Tadaepo Formation in Pusan area is, however, not tenable: Not only because the latter shows a short reverse polarity only in its lowest part of the sequence but also because the Andesites overlying it is wholly normally magnetized, in contrast to the frequent reverals in the case of both the Kosong Formation and Andesites above it.

• Progress in Medical Physics
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• v.19 no.2
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• pp.95-101
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• 2008

In this study, we observed the alteration of choline signal intensity in hippocampus region of the depressive rat model induced by forced swimming test (FST). The purpose of this study was to evaluate the antidepressant efficacy in the depressive animal model using MR spectroscopy. Fourteen experimentally naive male Sprague-Dawley rats weighting $160{\sim}180\;g$ were used as subjects. Drug injection group was exposed to the FST except for control group. The drugs were administered subcutaneously (SC) in a volume equivalent to 2ml/kg. And three injections were administered 23, 5, and 1h before beginning the given test. 1H MR spectra were obtained with use of a point resolved spectroscopy (PRESS) localization sequence performed according to the following parameters: repetition time, 2500 ms; echo time, 144 ms; 512 average; 2048 complex data points; voxel dimensions, $1.5{\times}2.5{\times}2.5\;mm^3$ ; acquisition time, 25min. There were no differences in NAA/Cr and Cho/Cr ratio between the right and the left hippocampus both normal control rats and antidepressant-injected rats. Also, no differences were observed in NAA/Cr and Cho/Cr ratio between the normal control rats and the antidepressant-injected rats both the right and the left hippocampus. In this study, we found the recovery of choline signals in the depressive animal model similar to normal control groups as injecting desipramine-HCl which was antidepressant causing anti-immobility effects. Thus, we demonstrated that MR spectroscopy was able to aid in evaluating the antidepressant effect of desipramine-HCl.

• Investigative Magnetic Resonance Imaging
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• v.12 no.2
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• pp.131-141
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• 2008

Purpose : To investigate the feasibility and accuracy of Proton Resonance Frequency (PRF) shift based magnetic resonance (MR) temperature mapping utilizing the self-developed center array-sequencing phase unwrapping (PU) method for non-invasive temperature monitoring. Materials and Methods : The computer simulation was done on the PU algorithm for performance evaluation before further application to MR thermometry. The MR experiments were conducted in two approaches namely PU experiment, and temperature mapping experiment based on the PU technique with all the image postprocessing implemented in MATLAB. A 1.5T MR scanner employing a knee coil with $T2^*$ GRE (Gradient Recalled Echo) pulse sequence were used throughout the experiments. Various subjects such as water phantom, orange, and agarose gel phantom were used for the assessment of the self-developed PU algorithm. The MR temperature mapping experiment was initially attempted on the agarose gel phantom only with the application of a custom-made thermoregulating water pump as the heating source. Heat was generated to the phantom via hot water circulation whilst temperature variation was observed with T-type thermocouple. The PU program was implemented on the reconstructed wrapped phase images prior to map the temperature distribution of subjects. As the temperature change is directly proportional to the phase difference map, the absolute temperature could be estimated from the summation of the computed temperature difference with the measured ambient temperature of subjects. Results : The PU technique successfully recovered and removed the phase wrapping artifacts on MR phase images with various subjects by producing a smooth and continuous phase map thus producing a more reliable temperature map. Conclusion : This work presented a rapid, and robust self-developed center array-sequencing PU algorithm feasible for the application of MR temperature mapping according to the PRF phase shift property.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.178-184
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• 2012

This study was carried out to decide ITS (internal transcribed spacer) sequence of some Korean native $Aster$ species and to resolve their relationship among Korean native $Aster$, including $Kalimeris$, $Gymnaster$, $Heteropappus$ genus separated from $Aster$ in a previously study based on the pappus length. We registered 11 ITS sequences of $Aster$ species including $A.$ $glehni$ to GenBank and those sequences were used for the cluster analysis with $Kalimeris$ species. The size of ITS1 was varied from 248 to 256 bp, while ITS2 was varied from 220 to 222 bp. The G + C content of the ITS region ranged from 49.4 to 53.5%. Pairwise comparison results showed that the substitution rate of ITS1 and ITS2 region was 9% and 10%, respectively. $Kalimeris$ sensu strict substitution rate was lower than that of $Aster$ sensu strict species. The strict consensus parsimonious cluster analysis showed $A.$ $tripolium$ is the first branching from the clade and the next is $A.$ $scaber$. The $Kalimeris$ species except for the $A.$ $hispidus$ were grouped into the same clade with high bootstrap value (91%) within $Aster$. $Gymnaster$ and $Heteropappus$ that has been classified by morphological characters were also grouped into broad sense $Aster$ clade. These results implied these three genera could be merged together into $Aster$ based on the ITS sequences.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.497-505
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• 2002

Background : INF-${\gamma}$ plays an important role in the host response to a mycobacterial infection. A complete IFN-${\gamma}$ receptor 1 deficiency is a life threatening condition because it renders patients highly susceptible to a mycobacterial infection. Several mutations in the IFN-${\gamma}$ receptor and STAT1 gene have been identified in the rare mycobacterial infections. These mutations have partial function of the IFN-${\gamma}$ receptor and similar pathologic features to clinical tuberculosis. Materials and Methods : The function of the IFN-${\gamma}$ receptor was evaluated in the patients with clinical tuberculosis. In addition, the DNA coding sequence of the IFNgR1 and STAT1 gene was also analyzed in disseminated tuberculosis patients who might have a defective IFN-${\gamma}$ receptor. Results : The cell surface expression levels of HLA-DR and CD64 in the PMBC after being stimulation with IFN-${\gamma}$ (100IU/ml, 1000IU/ml) were increased in both controls and patients. However, the rate of increase in both groups was similar. The production of TNF-${\alpha}$ in the response to stimulation with LPS was higher in the both groups ($850.7{\pm}687.8$ vs. $836.7{\pm}564.3$ pg/ml). Pretreatment with IFN-${\gamma}$ prior to LPS stimulation resulted in further increase in TNF-${\alpha}$ production between both groups ($2203.5{\pm}242.5$ vs. $2227.5{\pm}560.4$ pg/ml). However, the rate of the increase in TNF-${\alpha}$ production in the both groups was similar. The known mutations in the IFNgR1 and STAT1 coding sequences were not found in the genomic DNA of patients with disseminated tuberculosis. Conclusion : The functional and genetic defects of the IFN-${\gamma}$ receptor were not identified in clinical tuberculosis. This suggests the defective IFN-${\gamma}$ receptor that predispoe patients to a BCG or NTM infection can not alone account for the cases of clinical tuberculosis.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.2
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• pp.135-149
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• 2000

Most of prior works on testing parallel programs have concentrated on how to guarantee the reproducibility by employing event traces exercised during executions of a program. Consequently, little work has been done to generate test cases, especially, from specifications produced from software development process. In this research work, we devise the techniques for deriving test cases automatically from the specifications written in Message Sequence Charts(MSCs) which are widely used in telecommunication areas and develop the testing environment for performing module testing of parallel programs with derived test cases. For deriving test cases from MSCs, we have to uncover the causality relations among events embedded implicitly in MSCs. For this, we devise the methods for adapting vector time stamping to MSCs, Then, valid event sequences, satisfying the causality relations, are generated and these are used as test cases. The generated test cases, written in TTCN, are translated into CHILL source codes, which interact with a target module to be tested and test the validity of behaviors of the module. Since the testing method developed in this research work extracts test cases from the MSC specifications produced front telecommunications software development process, it is not necessary to describe auxiliary specifications for testing. In audition adapting vector time stamping generates automatically the event sequences, the generated event sequences that are ones for whole system can be used for individual testing purpose.

• Journal of Life Science
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• v.24 no.4
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• pp.403-410
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• 2014

This study was conducted in organic certification soil for the comparison of heavy metals, nutrients, and irrigated water standards to certify a farm. It was carried out in 811 paddy fields of organic rice (Oryza sativa L.) cultivated at Goseong-Gun. The amounts of 8 heavy metals, Cd, Cu, As, Hg, Pb, $Cr^{6+}$, Zn, and Ni were found to be 0.05, 14.5, 1.08, 0.92, 10.7, 1.34, 35.9, and 22.2 mg $kg^{-1}$ in regular sequence in the organic paddy soil, and they were 0.32, 13.6, 1.01, 0.03, 10.4, 0.91, 42.4 and 22.5 mg $kg^{-1}$ in the non-pesticide paddy soil. In comparing organic and non-pesticide paddy soil with respect to the chemical characteristics of the soil, the average pH and the amount of organic matter, available phosphate and available silicate were 5.88 and 27.6 g $kg^{-1}$, 134.5 mg $kg^{-1}$, and 165.3 mg $kg^{-1}$, while they were 5.78 and 32.1 g $kg^{-1}$, 107.7 mg $kg^{-1}$, and 175.2 mg $kg^{-1}$, respectively. The amount of exchangeable cation $K^+$, $Ca^{2+}$, and $Mn^{2+}$ were 0.25, 5.20, and 1.04 cmol+ $kg^{-1}$ in organic paddy soil, while they were 0.38, 5.13, and 1.19 cmol+ $kg^{-1}$ in non-pesticide paddy soil. The pH, DO, BOD, COD and SS conditions of the irrigated water used in the organic paddy soil were found to be 7.23, 8.40, 2.80, 1.86, and 2.58 mg $l^{-1}$ and the condition of irrigated water used in the non-pesticide paddy soil were found to be 7.65, 9.16, 2.25, 4.11, and 4.00 mg $l^{-1}$, respectively. Based on these findings, we suggest that environmentally-friendly certificates in Korea have to unify organic and non-pesticide agro-products in an organic standard in food policy and control because there is no difference between soil and irrigated water standards in the two certifications.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.40-49
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• 1999

A laboratory flume experiment, using turbulence-generating acryl tank and natural sediments, was conducted to investigate the effects of salinity, concentration of suspended sediment, turbulence and clay minerals on the flocculation and settling of fine-grained suspended sediments. While experiments were run, a sequence of water samples were taken near the bottom of the tank to analyze the variations of size distribution and relative contents of clay minerals. The results of the salinity experiment indicate that median settling velocity ($W_{50}$) increases linearly with salinity. Different settling processes of suspended sediments under variable concentrations appear to be predictable, depending upon the range of the suspension concentration. At concentrations less than 200 mg/l, $W_{50}$ is rarely varied with concentration probably because of the individual--grain settling mode. In the range of 200 to 13,000 mg/l show $W_{50}$ and concentration a good relationship following an empirical formula: $W_{50}=0.45C^{0.44}$. This relationship, however, no longer holds in concentrations exceeding 13,000 mg/l; instead, a more or less reverse one is shown. This result suggests an effect of hindered settling. The turbulence effect is somewhat different from that of concentration. Turbulence accelerates the flocculation and settling susepended sediments at low concentration (200 mg/l), whereas at high concentration turbulence breaks floes down and impedes the settling. Size distribution of suspended sediments sampled near the bottom of the tank tend to be more negatively skewed and leptokurtic in turbulent conditions compared to those in static conditions. The clay mineral analysis from the sequential water samples shows that over time the content of smectite decreases most rapidly with illite remaining concentrated in suspension. This means that smectite, among other clay minerals, plays the most effective role in the flocculation of fine-grained sediment in saline water.

• Journal of Life Science
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• v.27 no.11
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• pp.1331-1339
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• 2017

DNA barcoding is the identification of a species based on the DNA sequence of a fragment of the cytochrome C oxidase subunit I (COI) gene in the mitochondrial genome. It is widely applied to assist with the sustainable development of fishery-product resources and the protection of fish biodiversity. This study attempted to verify horse-head fish (Branchiostegus japonicus) and fake horse-head fish (Branchiostegus albus) species, which are commonly consumed in Korea. For the validation of the two species, a real-time PCR method was developed based on the species' mitochondrial DNA genome. Inter-species variations in mitochondrial DNA were observed in a bioinformatics analysis of the mitochondrial genomic DNA sequences of the two species. Some highly conserved regions and a few other regions were identified in the mitochondrial COI of the species. In order to test whether variations in the sequences were definitive, primers that targeted the varied regions of COI were designed and applied to amplify the DNA using the real-time PCR system. Threshold-cycle (Ct) range results confirmed that the Ct ranges of the real-time PCR were identical to the expected species of origin. Efficiency, specificity and cross-reactivity assays showed statistically significant differences between the average Ct of B. japonicus DNA ($21.85{\pm}3.599$) and the average Ct of B. albus DNA ($33.49{\pm}1.183$) for confirming B. japonicus. The assays also showed statistically significant differences between the average Ct of B. albus DNA ($22.49{\pm}0.908$) and the average Ct of B. japonicus DNA ($33.93{\pm}0.479$) for confirming B. albus. The methodology was validated by using ten commercial samples. The genomic DNA-based molecular technique that used the real-time PCR was a reliable method for the taxonomic classification of animal tissues.