• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.92-94
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• 1997

By measuring the increase of regional cerebral blood flow (rCBF) during the activation tasks, we can describe the brain regions that participate in certain specific functions. In this study, we composed the functional maps of verbal and nonverbal memory by performing the rCBF positron emission tomography (PET) activation studies and analyzing the differences between control and each activation state. Successive four tasks, which consist of one control state and three different activation tasks, were performed on 6 normal volunteers. All images were spatially normalized on standard atlas and the differences between control and activation states were statistically analyzed. The verbal memory activated predominantly left-sided structures, especially left superior temporal cortex, and the nonverbal short-term memory activated the right frontal cortex. Also, some regions ,where is thought to be related with short-term memory system, such as cingulate gyrus and hippocampus were activated. We conclude that biological validity of the brain regions for verbal and nonverbal memory could be tested using rCBF PET imaging technique and statistical analysis.

• Molecules and Cells
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• v.26 no.3
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• pp.250-257
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• 2008

Microsatellites or simple sequence repeats (SSR) are widely distributed in eukaryotic genomes and are informative genetic markers. Despite many advantages of SSR markers such as a high degree of allelic polymorphisms, co-dominant inheritance, multi-allelism, and genome-wide coverage in various plant species, they also have shortcomings such as low polymorphic rates between genetically close lines, especially in Capsicum annuum. We developed an alternative technique to SSR by normalizing and alternating anchored primers in random amplified microsatellite polymorphisms (RAMP). This technique, designated reverse random amplified microsatellite polymorphism (rRAMP), allows the detection of nucleotide variation in the 3' region flanking an SSR using normalized anchored and random primer combinations. The reproducibility and frequency of polymorphic loci in rRAMP was vigorously enhanced by translocation of the 5' anchor of repeat sequences to the 3' end position and selective use of moderate arbitrary primers. In our study, the PCR banding pattern of rRAMP was highly dependent on the frequency of repeat motifs and primer combinations with random primers. Linkage analysis showed that rRAMP markers were well scattered on an intra-specific pepper map. Based on these results, we suggest that this technique is useful for studying genetic diversity, molecular fingerprinting, and rapidly constructing molecular maps for diverse plant species.

• Ocean and Polar Research
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• v.29 no.4
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• pp.391-400
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• 2007

To identify the spatial distribution pattern of water quality in Masan Bay, Pearson's correlation as a common statistic method and Moran's I as a spatial autocorrelation statistics were applied to the hydrological data seasonally collected from Masan Bay for two years ($2004{\sim}2005$). Spatial distribution of salinity, DO and silicate among the hydrological parameters clustered strongly while chlorophyll a distribution displayed a weak clustering. When the similarity matrix of Moran's I was compared with correlation matrix of Pearson's r, only the relationships of temperature vs. salinity, temperature vs. silicate and silicate vs. total inorganic nitrogen showed significant correlation and similarity of spatial clustered pattern. Considering Pearson's correlation and the spatial autocorrelation results, water quality distribution patterns of Masan Bay were conceptually simplified into four types. Based on the simplified types, Moran's I and Pearson's r were compared respectively with spatial distribution maps on salinity and silicate with a strong clustered pattern, and with chlorophyll a having no clustered pattern. According to these test results, spatial distribution of the water quality in Masan Bay could be summed up in four patterns. This summation should be developed as spatial index to be linked with pollutant and ecological indicators for coastal health assessment.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.328-333
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• 2010

Comparative molecular field analyses (CoMFA) on the antiproliferative activity of N-substituted (R) 2-amino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole analogues (ADTs: 1-17) against bladder cancer (HCV29T) and rectal cancer (SW707) cells were studied quantitatively. The statistical predictability and fitness of CoMFA A1 model for bladder cancer cells were better than those of CoMFA F1 model for rectal cancer cells and the antiproliferative activity of ADTs depends on steric field (HCV29T: 93.1% & SW707: 83.8%). Also, from the contour maps of optimized CoMFA models, the activity for bladder cancer cells had predicted to increase when sterically favored groups were substituted on meta- and para-position, and sterically disfavored groups were substituted on one ortho-position of phenyl ring. The activity for rectal cancer cells had predicted to increase when sterically favored groups were substituted on para-position, and sterically disfavored groups were substituted on two ortho-position of phenyl ring as R-group.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.394-399
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• 2005

The comparative molecular field analyses (CoMFA) models for the herbicidal activities against barnyardgrass (Echinochloa crus-galli) and rice plant (Orysa sativa L.) by the substituent (R) on the hexahydroisoindol-1-one ring in a series of new 2-(4-chloro-5-(2-chloroallyloxy)-2-fluorophenyl)-3-thioalkoxy-2,3,4,5,6,7-hexahydroisoindol-1-one derivatives were conducted and discussed for selectivity between both plants. The statistical results of the two best models (B2 & R7) showed the best predictability for the herbicidal activities based on the cross-validated value $q_2(r^2cv.=0.529{\sim}0.755)$ and none cross-validated value $({r^2}_{ncv.}=0.937{\sim}0.945)$, respectively. Based on the findings, the predictability and fitness of the model (B2) for barnyard grass was better than that of the model (R7) for rice plant. From the two models and contour maps, it is revealed that the novel selective character for herbicidal activity between the two plants depend on the electrostatic field and steric field for the substituent of ortho-positions on the S-phenyl group as R-substituent in hexahydroisoindol-1-one ring.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.171-176
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• 2008

The comparative molecular similarity indices analysis (CoMSIA) models between 3${\beta}$-Hydroxy-12-oleanen-28-oic acid (1-30) analogues as substrate molecule and their inhibitory activities ($pI_{50}$) against protein tyrosine phosphatase (PTP)-1B were derived and discussed quantitatively. Listing in order, the CoMFA>CoMSIA${\geq}$HQSAR>2D-QSAR model, these QSAR models had the better statistical values. The optimized CoMSIA F1 model at grid 3.0${\AA}$ had the best predictability and fitness ($q^2$=0.754 and $r^2$=0.976) by field fit alignment. The order of contribution ratio (%) of CoMSIA fields concerning the inhibitory activities was a H-bond acceptor (48.9%), steric field (25.8%) and hydrophobic field (25.4%), respectively. Therefore, the inhibitory activities of substrate molecules against PTP-1B were dependent upon H-bond acceptor field (A) of $R_4$-group. From the analytical results of CoMSIA contour maps, oleanolic acid derivatives will have better inhibition activities if $R_1$ group has H-bond acceptor disfavor, $R_3$group has steric disfavor and $R_4$ group has steric, hydrophobic, H-bond favor.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.72-77
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• 2010

The minimum structural requirements of R-phenoxy substituents for herbicidal evaluation of O-(2-(R)-phenoxy)-ethyl-N-aralkylcarbamate (1-15) analogues against phytoene desaturase (PDS) based on the three dimensional quantitative structure-activity relationships (3D-QSARs: CoMFA and CoMSIA) were studied quantitatively. The correlativity and predictability ($r^2_{cv.}=0.753$ and $r^2_{ncv.}=0.964$) of the CoMFA 1 model were higher than those of the rest models. The PDS inhibitory activities from the optimized CoMFA 1 model were depend upon the steric field (44.0%), electrostatic field (36.3%), and hydrophobic field (19.6%) of O-(2-(R)-phenoxy)ethyl-Naralkylcarbamate analogues. From the CoMFA contour maps on the structure of the most active compound (5), if it has the steric favor at meta-, para-position on the phenoxy ring, the negative charge favor in meta-position and positive charge favor in the outside part of para-position, the inhibitory activity will be predicted to increase. Also, if ortho-, para-position, and outside of phenoxy ring are hydrophilic favor, and meta-position is hydrophobic favor, it is predicted that the inhibitory activity against PDS will be able to increase.

• The Korean Journal of Pesticide Science
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• v.6 no.3
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• pp.209-217
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• 2002

Two different QSAR methods, the comparative molecular similarity indices analyses (CoMSIA) and hologram quantitative structure activity relationship (HQSAR) are studied for the fungicidal activities ($pI_{50}$) of 2-N-benzyl-5-phenoxy-3-isothiazolone derivatives against sensitive (SPC: 95CC7105) and resisitive (RPC: 95CC7303) phytophthora blight fungus (Phytaphthora capsici). According to the findings from these QSAR investigation, the cross-validation value, $q^2$ and Pearson correlation coefficient, $r^2$ in the two methods were CoMSIA: RPC; $q^2=0.675,\;r^2=0.942$, SPC; $q^2=0.350,\;r^2=0.876$ and HQSAR: RPC; $q^2=0.519,\;r^2=0.869$, SPC; $q^2=0.483,\;r^2=0.990$, respectively. Therefore, the two models of comparative statistical significance were obtained. From the CoMSIA contour maps, the important factors for selective fungicidal activity against RPC are to be expected that the lower hydrophobic and not bulkiness substituent as hydrogen bonding acceptor have to introduce to meta and para-position (C1-C6) on the phenoxy moiety. And the results of prediction suggest that HQSAR method showed higher fungicidal activity than CoMSIA method.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1161-1171
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• 2018

Objective: The aim of this study was to investigate diffusion tensor (DT) imaging-derived properties of benign oligemia, true "at risk" penumbra (TP), and the infarct core (IC) during the first 3 hours of stroke onset. Materials and Methods: The study was approved by the local animal care and use committee. DT imaging data were obtained from 14 rats after permanent middle cerebral artery occlusion (pMCAO) using a 7T magnetic resonance scanner (Bruker) in room air. Relative cerebral blood flow and apparent diffusion coefficient (ADC) maps were generated to define oligemia, TP, IC, and normal tissue (NT) every 30 minutes up to 3 hours. Relative fractional anisotropy (rFA), pure anisotropy (rq), diffusion magnitude (rL), ADC (rADC), axial diffusivity (rAD), and radial diffusivity (rRD) values were derived by comparison with the contralateral normal brain. Results: The mean volume of oligemia was $24.7{\pm}14.1mm^3$, that of TP was $81.3{\pm}62.6mm^3$, and that of IC was $123.0{\pm}85.2mm^3$ at 30 minutes after pMCAO. rFA showed an initial paradoxical 10% increase in IC and TP, and declined afterward. The rq, rL, rADC, rAD, and rRD showed an initial discrepant decrease in IC (from -24% to -36%) as compared with TP (from -7% to -13%). Significant differences (p < 0.05) in metrics, except rFA, were found between tissue subtypes in the first 2.5 hours. The rq demonstrated the best overall performance in discriminating TP from IC (accuracy = 92.6%, area under curve = 0.93) and the optimal cutoff value was -33.90%. The metric values for oligemia and NT remained similar at all time points. Conclusion: Benign oligemia is small and remains microstructurally normal under pMCAO. TP and IC show a distinct evolution of DT-derived properties within the first 3 hours of stroke onset, and are thus potentially useful in predicting the fate of ischemic brain.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.148-148
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• 2018

Land subsidence caused by excessive groundwater pumping is a serious hydro-geological hazard. The spatial variability in land use, unbalanced groundwater extraction and aquifer characteristics are the key factors which make the problem more difficult to monitor using conventional methods. This study uses the European Space Agency (ESA) Sentinel satellites to investigate and monitor land subsidence varying with different land covers and groundwater use in the arid Quetta valley, Pakistan. The Persistent Scattering Differential Interferometry of Synthetic Aperture Radar (PS-DInSAR) method was used to develop 28 subsidence interferograms of the study area for the period between 16 Oct 2014 and 06 Oct 2016 using ESA's Sentinel-1 SAR data. The uncertainty of DInSAR result is first minimized by removing the dynamic effect caused by atmospheric factors and then filtered using the radar Amplitude Dispersion Index (ADI) to select only the stable pixels. Finally the subsidence maps were generated by spatially interpolating the land subsidence at the stable pixels, the comparison of DInSAR subsidence with GPS readings showed an R 2 of 0.94 and mean absolute error of $5.7{\pm}4.1mm$. The subsidence maps were also analysed for the effect of aquifer type and 4 land covers which were derived from Sentienl-2 multispectral images. The analysis show that during the two year period, the study area experienced highly non-linear land subsidence ranging from 10 to 280 mm. The subsidence at different land covers was significantly different from each other except between the urban and barren land. The barren land and seasonally cultivated area show minor to moderate subsidence while the orchard and urban area with high groundwater extraction rate showed excessive amount of land subsidence. Moreover, the land subsidence and groundwater drawdown was found to be linearly proportional to each other.