• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.101-109
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• 2003

The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest Bone. At the old-growth deciduous forest near Soribong-peak (533.1 m) in KEF, we have established a 1 ha permanent plot ($100m{\times}100m$) and a flux tower, and the site was registered as a KLTER(Korean long-term ecological research network) and DK site of KoFlux. In this site, we made a stemmap of trees and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2 cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area $28.0m^2$/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66 cm. Soil texture is loam or sandy loam, and its pH was f개m 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the 1.2 m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30 cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. These ground survey and monitoring data will give some important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1366-1372
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• 2018

Objective: A disintegrin and metallopeptidase with thrombospondin motifs type 8 (ADAMTS8) is crucial for diverse physiological processes, such as inflammation, tissue morphogenesis, and tumorigenesis. The chicken ADAMTS8 (chADAMTS8) gene was differentially expressed in the kidney following exposure to different calcium concentrations, suggesting a pathological role of this protein in metabolic diseases. We aimed to examine the molecular characteristics of chADAMTS8 and analyze the gene-expression differences in response to toll-like receptor 3 (TLR3) stimulation. Methods: The ADAMTS8 mRNA and amino acid sequences of various species (chicken, duck, cow, mouse, rat, human, chimpanzee, pig, and horse) were retrieved from the Ensembl database and subjected to bioinformatics analyses. Reverse-transcription polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR) experiments were performed with various chicken tissues and the chicken fibroblast DF-1 cell line, which was stimulated with polyinosinic-polycytidylic acid (poly[I:C]; a TLR3 ligand). Results: The chADAMTS8 gene was predicted to contain three thrombospondin type 1 (TSP1) domains, whose amino acid sequences shared homology among the different species, whereas sequences outside the TSP1 domains (especially the amino-terminal region) were very dif­ferent. Phylogenetic analysis revealed that chADAMTS8 is evolutionarily clustered in the same clade with that of the duck. chADAMTS8 mRNA was broadly expressed in chicken tissues, and the expression was significantly up-regulated in the DF-1 cells in response to poly(I:C) stimulation (p<0.05). These results showed that chADAMTS8 may be a target gene for TLR3 signaling. Conclusion: In this report, the genetic information of chADAMTS8 gene, its expression in chicken tissues, and chicken DF-1 cells under the stimulation of TLR3 were shown. The result suggests that chADAMTS8 expression may be induced by viral infection and correlated with TLR3-mediated signaling pathway. Further study of the function of chADAMTS8 during TLR3-dependent inflammation (which represents RNA viral infection) is needed and it will also be important to examine the molecular mechanisms during different regulation, depending on innate immune receptor activation.

• The Journal of the Acoustical Society of Korea
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• v.39 no.5
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• pp.379-389
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• 2020

In this study, the flow and noise performances of high-speed fan motor unit for cordless vacuum cleaner is improved by optimizing the impeller which drives the suction air through flow passage of the cordless vacuum cleaner. Firstly, the unsteady incompressible Reynolds averaged Navier-Stokes (RANS) equations are solved to investigate the flow through the fan motor unit using the computational fluid dynamics techniques. Based on flow field results, the Ffowcs-Williams and Hawkings (FW-H) integral equation is used to predict flow noise radiated from the impeller. Predicted results are compared to the measured ones, which confirms the validity of the numerical method used. It is found that the strong vortex is formed around the mid-chord region of the main blades where the blade curvature change rapidly. Given that vortex acts as a loss for flow and a noise source for noise, impeller blade is redesigned to suppress the identified vortex. The response surface method using two factors is employed to determine the optimum inlet and outlet sweep angles for maximum flow rate and minimum noise. Further analysis of finally selected design confirms the improved flow and noise performance.

• Korean Journal of Weed Science
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• v.6 no.2
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• pp.134-145
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• 1986

The experiment was crried out to evaluated the herbicidal properties of bensulfuron methyl [methyl 2-[[[[[(4, 6-dimethoxy pyrimidine-2yl) amino] carbonyl] amino] sulfonyl] methyl] benzoate]. No phytotoxicity was observed when bensulfuron methyl was applied at 3 and 6 g a.i./ 10a while the application rate 12 g a.i./10a slightly retared the growth of rice. The phytotoxicity decreased as the application time was delayed. The effect of application rate, leaching grade, transplanting depth, soil type and temperature on crop injury was little. Japonica variety (Dong-Jin) was more sensitive to bensulfuron methyl than indica X japonica variety (Sam-Kang). Bensulfuron methyl controlled effectively perennial weeds such as Sagittaria pygmaea Miq., Potamogeton diatinctus A. Benn., Cyperus serotinus Rottb., Sagittaria trifolia L., Eleocharis kuroguwai Ohwi. including most annual weeds except Echinochloa crus galli P. Beauv. The effect slightly decreased with lowering the temperature increasing the leaching grade. Application time and soil type employed did not affect the weeding effect.

• Fire Science and Engineering
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• v.23 no.5
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• pp.24-31
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• 2009

Based on fallen leaves of major Korean conifer species 'Pinus densiflora' and major Korean broadleaved species 'Quercus variabilis', this study sought to identify combustion emission gas types and measure their concentration by means of FTIR (Fourier Transform Infrared) spectrometer. As a result, it was found that there were total 13 types of combustion gas detected from fallen leaves of Pinus densiflora and Quercus variabilis, such as carbon monoxide, carbon dioxide, acetic acid, butyl acetate, ethylene, methane, methanol, nitrogen dioxide, ammonia, hydrogen fluoride, sulfur dioxide and hydrogen bromide. Notably, nitrogen monoxide was additionally detected from fallen leaves of Quercus variabilis. It was found that the overall concentration of combustion gas emitted from the fallen leaves of Pinus densiflora was 4.5 times higher than that from fallen leaves of Quercus variabilis. Particularly, it was found that emission concentration of some combustion emission gas types like carbon monoxide, carbon dioxide and butyl acetate exceeded the upper limit of their time-weighted average (TWA, ppm), while the emission concentration of carbon monoxide and carbon dioxide exceeded their short-term exposure limit (STEL, ppm) for both species. Thus, it was found that carbon monoxide and carbon dioxide have higher hazard to health than other gas types, because these two gas types account for higher than 99% of overall gas emission due to combustion of surface fire starting from litter layer in forest.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.444-450
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• 2013

A Gram-negative, strictly aerobic, non-motile, non-spore-forming, and rod-shaped bacterial strain designated FW-$6^T$ was isolated from a freshwater sample and its taxonomic position was investigated by using a polyphasic approach. Strain FW-$6^T$ grew optimally at $10-42^{\circ}C$ and at pH 7.0 on nutrient and R2A agar. Strain FW-$6^T$ displayed ${\beta}$-glucosidase activity that was responsible for its ability to transform ginsenoside $Rb_1$ (one of the dominant active components of ginseng) to Rd. On the basis of 16S rRNA gene sequence similarity, strain FW-$6^T$ was shown to belong to the family Sphingomonadaceae and was related to Novosphingobium aromaticivorans DSM $12444^T$ (98.1% sequence similarity) and N. subterraneum IFO $16086^T$ (98.0%). The G+C content of the genomic DNA was 64.4%. The major menaquinone was Q-10 and the major fatty acids were summed feature 7 (comprising $C_{18:1}{\omega}9c/{\omega}12t/{\omega}7c$), summed feature 4 (comprising $C_{16:1}{\omega}7c/iso-C_{15:0}2OH$), $C_{16:0}$, and $C_{14:0}$ 2OH. DNA and chemotaxonomic data supported the affiliation of strain FW-$6^T$ to the genus Novosphingobium. Strain FW-$6^T$ could be differentiated genotypically and phenotypically from the recognized species of the genus Novosphingobium. The isolate that has ginsenoside converting ability therefore represents a novel species, for which the name Novosphingobium ginsenosidimutans sp. nov. is proposed, with the type strain FW-$6^T$ (= KACC $16615^T$ = JCM $18202^T$).

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.519-526
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• 2015

This study was investigated to analyze stand structure in Daegu Dodong T.orientalis Forest for conservation Thuja orientalis forest. Results of cluster analysis, it was classified to Quercus variabilis group(A), Quercus variabilis-Quercus mongolica group(B), Pinus densiflora group(C), Thuja orientalis group(D). Charaters of location environments for D group were analyzed that altitude 99.3 m, slope $59^{\circ}$, rock exposure 68.3%, BHA $21.8m^2/ha$ and North West aspects. The MRPP-test, It classified groups, appropriately. Importance value of D group was T. orientalis 85.42, Q. variabilis 1.28, P.densiflora 1.30, Fraxinus rhynchophylla 3.56 etc. DBH classes of D group were expressed inverted-J-shaped curve. H' was resulted in 0.600~0.834, H'max 1.317~1.466, J' 0.456~0.594, D' 0.405~0.544. Indecator species Analysis were conducted that woody plants were 4 taxa, Herbal plants 9 taxa.

• Geophysics and Geophysical Exploration
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• v.9 no.3
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• pp.241-249
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• 2006

Due to the long tectonic history and the very complex geologic formations in Korea, the anisotropic characteristics of subsurface material may often change very greatly and locally. The algorithms commonly used, however, may not give sufficiently precise computational results of traveltime data particularly for the complex and strong anisotropic model, since they are based on the two-dimensional (2D) earth and/or weak anisotropy assumptions. This study is intended to develope a three-dimensional (3D) modeling algorithm to precisely calculate the first arrival time in the complex anisotropic media. Considering the complex geology of Korea, we assume 3D TTI (tilted transversely isotropy) medium having the arbitrary symmetry axis. The algorithm includes the 2D non-linear interpolation scheme to calculate the traveltimes inside the grid and the 3D traveltime mapping to fill the 3D model with first arrival times. The weak anisotropy assumption, moreover, can be overcome through devising a numerical approach of the steepest descent method in the calculation of minimum traveltime, instead of using approximate solution. The performance of the algorithm developed in this study is demonstrated by the comparison of the analytic and numerical solutions for the homogeneous anisotropic earth as well as through the numerical experiment for the two layer model whose anisotropic properties are greatly different each other. We expect that the developed modeling algorithm can be used in the development of processing and inversion schemes of seismic data acquired in strongly anisotropic environment, such as migration, velocity analysis, cross-well tomography and so on.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1375-1387
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• 2016

The purpose of this study was to evaluate the effect of exercise on cognitive function in the elderly through a systematic literature review and meta-analysis. For the study purpose, 14 studies were selected through a systematic process of using several databases and 11 studies were used to estimate the effect size of exercise on cognitive function. Meta-analysis was performed using a random effects model, and the effect size on cognitive function was calculated. The effect size for cognitive function of exercise intervention was Hedges' g=1.05 (95% CI: 0.61~1.50), indicating a large effect size. For heterogeneity, moderator analysis was performed using intervention, number of times per week, intervention duration, and cognitive function measurement. Cognitive function measurement was statistically significant, the other moderators did not significant difference. Results support that exercise has significant positive effects on cognitive function in elderly in korea. It also provided a basis that can be applied to exercise intervention design for cognitive function.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.581-590
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• 1998

We developed a novel water-soluble camptothecin analobue, CKD602, and evaluated the inhibition of topoisomerase I and the antitumor activities against mammalian tumor cells and human tumor xenografts. CKD602 was a nanomolar inhibitor of the topoisomerase I enzyme in the cleavable complex assay. CKD602 was found to be 3 times and slightly more potent than topotecan and camptothecin as inhibitors of topoisomerase, respecitively. In tumor cell cytotoxicity, CKD602 was more potent than topotecan in 14 out of 26 human cancer cell lines tested, while it was comparable to camptothecin. CKD602 was tested for the in vivo antitumor activity against the human tumor xenograft models. CKD602 was able to imduce regression of established HT-29, WIDR and CX-1 colon tumors, LX-1 lung tumor, MX-1 breast tumor and SKOV-3 ovarian tumor as much as 80, 94, 76, 67, 87% and 88%, respectively, with comparable body weight changes to those of topotecan. Also the therapeutic margin (R/Emax: maximum tolerance dose/$ED-{58}$) of CKD602 was significantly higher than that of topotecan by 4 times. Efficacy was determined at the maximal tolerated dose levels using schedule dependent i.p. administration in mice bearing L1210 leukemia. On a Q4dx4 (every 4 day for 4 doses) schedule, the maximum tolerated dose (MTD) was 25 mg/kg per administration, which caused great weight loss and lethality in <5% tumor bearing mouse. this schedule brought significant increase in life span (ILS), 212%, with 33% of long-term survivals. The ex vivo antitumor activity of CKD602 was compared with that of topotecan and the mean antitumor index (ATI) values recorded for CKD602 were significantly higher than that noted for topotecan. From these results, CKD602 warrants further clinical investigations as a potent inhibitor of topoisomerase I.