• Korean Journal of Ichthyology
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• v.34 no.4
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• pp.231-243
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• 2022

To investigate the taxonomic status of undescribed species Acheilognathus sp. HR from Korean Acheilognathidae discovered from the Dalcheon River, a tributary of the Hangang River, molecular phylogenetic and morphological characteristics were compared and analyzed with previous studies. As a result of molecular phylogenetic analysis, A. sp. HR formed the same genetic clade as the five subspecies of Acheilognathus tabira, but formed a separate monophyletic group based on the unique genotype, showing clear differences. As a result of morphological analyses, the dorsal fin color in males is grayish and the nuptial coloration of the outer edge of the anal fin is white. The outer edges of the dorsal and anal fins are convexly rounded. A black blotch is present on the dorsal fin of the juvenile, but there is a black blotch absent on the dorsal fin of the small adult female. In the counts, the number of branched dorsal rays is 12~13. In the measurements, the length of the barbels is short and the body depth is deep. Therefore, the A. sp. HR of Hangang River is considered at the level of a distinct species distinguished from each other by the five subspecies of A. tabira by molecular phylogenetic, morphological, and limited distributional characteristics.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.621-629
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• 2016

Recently, the researches on quantitative structure activity relationship (QSAR) for describing toxicities or activities of chemicals based on chemical structural characteristics have been widely carried out in order to estimate the toxicity of chemicals in multiuse facilities. Because the toxicity of chemicals are explained by various kinds of molecular descriptors, an important step for QSAR model development is how to select significant molecular descriptors. This research proposes a statistical selection of significant molecular descriptors and a new QSAR model based on partial least square (PLS). The proposed QSAR model is applied to estimate the logarithm of partition coefficients (log P) of 130 polychlorinated biphenyls (PCBs) and lethal concentration ($LC_{50}$) of 14 PCBs, where the prediction accuracies of the proposed QSAR model are compared to a conventional QSAR model provided by OECD QSAR toolbox. For the selection of significant molecular descriptors that have high correlation with molecular descriptors and activity information of the chemicals of interest, correlation coefficient (r) and variable importance of projection (VIP) are applied and then PLS model of the selected molecular descriptors and activity information is used to predict toxicities and activity information of chemicals. In the prediction results of coefficient of regression ($R^2$) and prediction residual error sum of square (PRESS), the proposed QSAR model showed improved prediction performances of log P and $LC_{50}$ by 26% and 91% than the conventional QSAR model, respectively. The proposed QSAR method based on computational toxicology can improve the prediction performance of the toxicities and the activity information of chemicals, which can contribute to the health and environmental risk assessment of toxic chemicals.

• Journal of Photoscience
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• v.9 no.2
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• pp.317-319
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• 2002

All-optical switching has been demonstrated in bacteriorhodopsin (bR) based on nonlinear intensity induced excited state absorption. The transmission of a cw probe laser beam at 410 nm corresponding to the peak absorption of M state through a bR film is switched by a pulsed pump laser beam at 570 nm that corresponds to the maximum initial 8 state absorption. The switching characteristics have been analyzed using the rate equation approach considering all the six intermediate states (B, K, L, M, N and 0) in the bR photocycle. The switching characteristics are shown to be sensitive to life time of the M state, absorption cross-section of the 8 state at probe wavelength ($\sigma$ $\_$Bp/) and peak pump intensity. It has been shown that the probe laser beam can be completely switched off (100 % modulation) by the pump laser beam at relatively low pump powers, for $\sigma$$\_$Bp/ = O. The switching characteristics have been used to design all-optical NOT, OR, AND and the universal NOR and NAND logic gates for optical computing with two pulsed pump laser beams.

• Journal of Life Science
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• v.14 no.3
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• pp.400-405
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• 2004

Morphological characteristics of Kalopanox pictus Nakai were studied to examine population differentiation of this species. Based on a phenogram of using 23 morphological characteristics, differentiation of regions were distinct. Collections of 138 specimens from nine populations served as operational taxonomic unit (OTU's) were examined for phenotypic similarity and morphological variation using clustering (Ward's minimum variance method) and principal component analysis (PCA). The first three principal components were responsible for 77.0% of the total variance. Principal component 1 explained 52% of the total variance and was contributed to by the number of palmately parted, the number of pinnately lobed, and width between two lateral lobe apex.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.698-705
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• 2008

When electromagnetic waves propagate through atmosphere, waves are affected by various factors. Atmosphere normally consists of different molecular species, water vapours, rain, fog, snow and small suspended particles called aerosols. The distributions of atmosphere molecules, water vapours, rain rate, snowfall and aerosol are dependent on geometrical regions or environment. In order to predict propagation characteristics in atmospheric environment, statistical analysis of the relevant parameters such as temperature, humidity, atmospheric pressure, wind speed, areosol and rainfall is crucial. In this paper, we performed a long-term statistical analysis for the atmospheric parameters in domestic environments and analyzed the propagation characteristics through atmosphere based on that.

• Journal of Fashion Business
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• v.22 no.4
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• pp.93-105
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• 2018

Using FDM 3D printing, yarn shape and composition were modeled and 3D printed with PLA and TPU filaments currently used for apparel. Based on this, mechanical characteristics were measured to determine 3D printing yarn according to type of filaments in the 3D printed output and deformation and recovery characteristics due to differences in structure type. As a result of examining tensile and shear characteristics of PLA and TPU 3D printing compiles, TPU overall was measured with significantly lower stress than PLA. This is due to high elasticity of TPU's character, revealing that it has better flexibility than PLA. In addition, during deformation due to external forces, the more freedom between the head and foot parts of the loop, and the lower the force associated with each other, the more flexible it is. TPU revealed that it was easier to tension and recovery from tensile deformation than PLA, indicating potential for clothing materials using 3D printing. If high-molecular materials, such as PLA flexibility, it is likely to provide some flexibility through development of styles, including degree of freedom in modeling. Based on this, we provide basic data for developing 3D printing textures that can be satisfied with textile for apparel.

• Journal of Environmental Science International
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• v.21 no.11
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• pp.1297-1305
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• 2012

Clonal plants combine sexual and clonal reproduction, which contribute differently to plant fitness. Reproductive analyses have highlighted the importance of clonal growth in shaping the spatial genetic structure in Potentilla conferta Bunge, a herbaceous rhizomatic clonal distributed in hot sand dunes. We investigated the reproduction system of P. conferta at two populations in Mongol and three natural populations in Uzbekistan. The measurements of 19 quantitative or qualitative morphological characters were taken on each of total individuals directly from their natural habitats. Some morphological characteristics between Mongolia and Uzbekistan populations showed a slight heterogeneity of variance. Especially, the length of internodes (LFI and LSI) and characteristics of root (LLR and NOR) were shown a significant difference between two countries (P<0.05). P. conferta of Uzbekistan has most ramets at short distance intervals 30~100 cm. In light conditions, P. conferta of Uzbekistan was significantly less resilience than P. conferta of Mogol. In drought conditions, although there was not shown significant difference, P. conferta in Uzbekistan was less resilience than that in Mogol. The core analysis indicates that P. conferta in Uzbekistan is the more resistant than that of Mongol and seems to do by sexual reproduction strategy during several strong environmental disadvantages such as drought events.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.221-228
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• 2005

A total of 179 isolates of Trichoderma spp. were collected from oyster mushroom substrates in Korea. On the basis of morphological and cultural characteristics, Trichoderma isolates were divided into seven groups, namely T. atroviride, T. citrinoviride, T. harzianum, T. longibrachiatum, T. virens, and two unidentified species, referred to as Trichoderma sp. 1 and 2. The predominant species was Trichoderma sp. 2 (n=86) followed by Trichoderma sp. 1 (n=52). Trichoderma sp. 1 and 2 were morphologically distinct not only from the other species of Trichoderma reported but also from each other in the characteristics such as mycelial growth rate, colony appearance, shape of conidia and conidiophores and branching pattern of phialides, although branching pattern of phialides of Trichoderma sp. 1 was similar to that of T. harzianum. In virulence test, the degree for compost colonization of Trichoderma sp. 2 was significantly greater than that of the other Trichoderma species. Trichoderma sp. 2 was found to be the main cause of green mold disease in oyster mushroom production. More work including molecular characterization is needed to confirm the species of Trichoderma sp. 1 and 2.

• Korean Journal of Veterinary Service
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• v.18 no.1
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• pp.22-32
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• 1995

A partial characteristics and pathogenicity of Aeromonas salmonicida strain isolated from diseased cultured eel were studied. On the biochemicial characteristics of the isolate strain was classified into atypical Aeromonas salmonicida : the characteristics of the isolate strain differed from those of the subspecies of Achromogenes, masoucida and salmonicida. It strain was named atypical Aeromonas salmonicida EL-1 and it grew at optimal pH 7.5 and l% Nacl. In the pathogenicity test, at one to two days post infection, the motality of artificially infected eels with $1{\times}10^8$ and $1.0{\times}10^7$ cfu/fish group was 100%, and at three days pos-infection, in the $1.0{\times}10^6$ /cfu /fish infected group, the epizootic haemorrhagic ulcer was developed, and haemorragic red sports were formed around abdomen and fins and its died (40%). Total cell protein peptide bands of the A. salmonicida EL-1 were presented betweeon 11.8~102 Kd in molecular weight by the electrophoretic analysis and appeared 28 bands in all. Drug sensitivity of atypical A. salmonicida EL-1 strain was sensitivity to chlorampenicol, gentamicin, kanamycin, streptomycin and sulfamethoxazole /trimethoprim and intermidiate to ampiclin and neomycin resistant to cephalotin, erythromycin, lincomycin and tetracycline.

• Mycobiology
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• v.35 no.4
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• pp.180-185
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• 2007

Grape fruits with blue mold symptoms were collected from house storages in different locations in Korea and were investigated for their association with Penicillium species. A total of 12 isolates of Penicillium were isolated from the collected fruits. Based on morphological and cultural characteristics and ${\beta}-tublin$ gene sequence data analysis, they were identified as P. bialowiezense, P. citrinum, P. echinulatum, P. expansum, P. solitum and unidentified Penicillium species. P. solitum was the predominant followed by P. expansum. P. bialowiezense and P. echinulatum were newly recorded in Korea. ${\beta}-Tubulin$ gene sequences could be used to distinguish each species of Penicillium and the molecular groups were correlated well with the morphological species. The unidentified species was supposed to be a new species, not previously reported in literature.