• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.39-46
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• 2005

The 21 strains of Korean entomopathogenic nematodes, {Heterorhabditis bacteriophora Hamyang strain(HbH), Heterorhabditis sp. 202, 205, 217, Heterorhabdiris sp. KCTC 0991BP strain, Steinernema carpocapsae Pocheon(ScP), S. longicaudum Gonaju, S. longicaudum Nonsan, Steinernema sp. 7,24, 52, 55, 60, 64, 206, 207, 209, 210, 219, and 227 strain} were evaluated for the control of a turfgrass insect pest, Exomala orientalis. Heterorhabditis spp. showed higher pathogenicity than Steinernema spp. against 3rd instar larvae of E. orientalis with $55\%$ mortality by Heterorhabditis sp. 202 strain and $50\%$ by HbH and Heterorhabditis sp.205 strain at the rate of 200 infective juveniles per larva 14 days later after treatment. The number of infective juveniles of Korean entomopathogenic nematodes in 3rd instar larvae of E. orientalis was higher in Heterorhabditis spp. than in Steinernema spp.. In general, numbers of produced infective juveniles of three species were much higher, i.e., Heterorhabditis sp.202 strain produced 273,064 infective juveniles, S. carpocapsae Pocheon strain 273,043, and Heterorhabditis sp. 217 strain 248,887, respectively.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.29-33
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• 2007

The objective of this research was to provide basic information of Thuja orientalis stand for prediction system, which consists of the best model of diameter and basal area. Data was from cores of 45 sample trees of Thuja orientalis stand that was designated as a natural monument (No. 62) in Yeongcheon, Chungbuk. Of the projection functions tested, polymorphic equation using the overlapping data showed higher precision of the fitting than anamorphic equation using. In diameter growth, Schumacher polymorphic equation of $D_2={\exp}({\ln}(D_1)(T_1/T_2)^{0.4495}+3.8535(1-(T_1/T_2)^{0.4495}))$, and in basal area growth, Schumacher polymorphic equation of $BA_2={\exp}({\ln}(BA_1)(T_1/T_2)^{0.1235}+11.3793(1-(T_1/T_2)^{0.1235}))$ showed the highest precision of the fitting among them. The equation, therefore, could be available as basic information for estimation of growth and management of Thuja orientalis stand.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.11-16
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• 2016

Declines in amphibian populations are occurring worldwide, and have been attributed to many factors, including anthropogenic environmental changes. One of the ramifications of such declines is abnormalities in many amphibian species. A strong association has been detected between human activities and abnormalities in amphibian populations, but studies on this association are largely focused on lentic species. In this study, it was analyzed whether the degree of local human activity was associated with the rate of abnormalities in Bombina orientalis which inhabited lotic environments. We found that the proportions of abnormalities in wild populations of B. orientalis increased, when i) the closest human land use was located within 100 m from the frogs' habitat, and ii) the proportion of human land use within a 300-m radius was high. Our findings suggest that human activity has a negative impact on the fitness of nearby amphibian populations, and that wild populations very close to human-induced disturbance are affected.

• Journal of agricultural medicine and community health
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• v.26 no.2
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• pp.161-179
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• 2001

Recent patterns of infections with digenetic larval trematodes from fresh-water fish were studied in five locations of the river Taega during the period from October, 1998 to September, 2000, and compared with the data reported previously in the same river. The fish were collected using following techniques ; fishing, throwing a castnet, and using a bait of crushed oil cake in a transparent plastic bowl. Of 19 species of fish examined, eight species of encysted larvae, Clonorchis sinensis, Cyathocotyle orientalis, Centrocestus armatus, Clinostomum complanatum, Exorchis oviformis, Metagonimus species, Metacecaria hasegawai, and Metorchs orientalis, and two kinds of undetermined cyst A and C were found. The encysted larvae of Exorchis oviformis were found most frequently from 12 species of fresh-water fish, followed by Metacercaria hasegawai larvae from 9 species, the cyst of Clonorchis sinensis and Cyathocotyle orientalis from 7 species, Centrocestus armatus from 3 species, Clino- stomum complanatum from 2 species, and Metorchis orientalis from 1 species. The infection rates of fish with Clonorchis sinensis larvae were lower than those reported in 1993, whereas their intensity of infection was found lowered in 3 species, Pungtungia herz I, Saurogobio dabry i, and Squalidus jap onicus coreanus. The infection rates and intensity of 6 species of fish with Metagonimus sp ecies larvae were lower than the results in 1993, while the rates in several species of fish with Exorchis oviformis rather higher. The encysted larvae of Cyathocotyle orientalis, Metacercaria hasegawai, and Metorchis orientalis showed variations in infection rates of fish in 1993 and in the present study. However, It was impossible to compare the infection rates for the encysted larvae on the scales, fins and tail as they varied so considerably in both 1993 and 2000 surveys. This study indicate that the rate of infection with digenetic larval trematodes in fresh-water fish was still relatively high in the river Taega, and the metacercarial burden in the fish varies greatly by different fish in 1993.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.3
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• pp.72-83
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• 2015

A plant diversity, which consists of indigenous plant community with Orientla thuja community (Natural monument no. 1) in Dodong, Daegu, is identified and analyzed as ecological characteristic to consider worth plants and vegetation resource of the region. The vascular plants of Thuja orientalis community were listed as 219 taxa (3.7% of all 4,881 taxa of Korean vascular plants); 67 families, 147 genera, 199 species, 16 varieties, and 4 forms. Vulnerable species (VU) and least concerned species (LC) were recorded based on IUCN standard; Koelretueria paniculata (VU), Thuja orientalis (LC), and Exochorda serratifolia (LC). Although the study site is a non-limestone area, a total of 15 taxa of calciphilous plants were identified; Cheilanthes argentea, Hypodematium glandulosopilosum, Asplenium retamuraria, Thuja orientalis, Spiraea blumei, Smilax sieboldii, etc. A total of 4 taxa endemic plants were identified; Prunus mandshurica for. barbinervis, Lespedeza maximowiczii var. tomentella, Forythia koreana (artificial origin), and Veronica pyrethrina. Among the list, 8 taxa of naturalized plants were identified; Fallopia dentatoalalta, Rumex crispus, Nasturtium officinale, Bidens frondosa, Erigeron annuus etc. Naturalization rate (NR) was 3.6%, of all 219 taxa of vascular plants and urbanization index (UI) was 2.2% of all 321 taxa of naturalized plants. Thuja orientalis occupies a lot of indigenous landscape in this study area which is the southern-limited part of a natural distribution where it can survive. The T. orientalis community, where indigenous plants have formed a characterful species composition based on habitat, has been confirmed as a worth national vegetation resource in an indigeous flora. It has been considered of plans for persistent conservation.

• Development and Reproduction
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• v.19 no.1
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• pp.1-10
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• 2015

The purpose of the present study was to examine the seminiferous epithelium cycle of Bombina orientalis using a light microscope. The cycle was divided into a total of 10 stages, according to the morphological characteristics of the cells. The spermatogenetic cells included primary spermatogonia, secondary spermatogonia, primary spermatocytes, secondary spermatocytes, spermatid and sperm. At stage I, the primary spermatogonia was located closer to basal lamina of the seminiferous tubule without spermatocyst formations. Especially at the stage II, the secondary spermatogonia were located in the spermatocyst. The primary and secondary spermatocytes were found from stages III to VI. The secondary spermatocytes were smaller in size than the primary spermatocytes, but they had thicker nucleoplasm and smaller nuclei. The round-shaped, early sperm cells were formed in stage VII, and further divided at stage VIII to have more concentrated nucleoplasm before division to matured sperm cells. At stage X, the matured sperm cells emerged from the spermatocyst. Considering the above results, this study presented the special characteristics in the generation and type of sperm formation. The germ cell formation occurred in various stages, like the perspectives of Franca et al (1999), ultimately, providing taxonomically useful information.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.968-978
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• 2007

A pathogenic nematode, Butlerius sp., was isolated from Oriental beetle, Blitopertha orientalis. The infective juveniles exhibited dose-as well as time-dependent entomopathogenicity on the larvae of B. orientalis. Two bacterial species, Providencia vermicola (KACC 91278) and Flavobacterium sp. (KACC 91279), were isolated from the infective juveniles and identified. P. vermicola outnumbered Flavobacterium sp. in the nematode host, in which the colony density of P. vermicola was found to be 21 times higher than that of Flavobacterium sp. However, when the two bacterial species were cocultured in culture media without the nematode host, they showed similar growth rates. Both bacteria induced significant entomopathogenicity against Spodoptera exigua larvae infesting economically important vegetable crops, where P. vermicola was more potent than Flavobacterium sp.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.218-225
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• 1999

A protease without tryptic and chymotryptic activities was purified from the hepatopancreas of shrimp, Penaeus orientalis, using Q-Sepharose ionic exchange, benzamidine Sepharose-6B affinity, Mono-Q, and gel chromatography. Molecular weight (M.W.) of the protease was estimated to be 27kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS­PAGE). The amino acid composition of the protease was different from that of protease from P. japonicus or trypsin from P. orientalis. The protease was completely inhibited by benzamidine, $N\alpha-p-tosyl-L-lysine$ chloromethyl ketone (TLCK), and phenylmethylsulfonyl fluoride (PMSF) and was not affected by leupeptin, pepstatin, N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), iodoacetate, and ethylenediamine tetra acetate (EDTA). The enzyme did not have any activity against Na-benzoyl-DL-arginine p-nitroanilide (BAPNA) or N-benzoyl-L-tyrosine ethyl ester (BTEE) which are specific substrates of trypsin and chymotrypsin, respectively. However, the protease showed hydrolytic activity for a carboxyl terminal of Tyr, Trp, Phe, Glu, and Cys.

• Natural Product Sciences
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• v.27 no.4
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• pp.293-299
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• 2021

The ethyl acetate fractions prepared from the leaves of Thuja orientalis significantly inhibited nitric oxide (NO) production in lipopolysaccharide-stimulated BV2 microglial cells. According to bioassay-coupled LC-QTOF MS/MS, the components near 22 and 25 mins in the mass chromatogram highly inhibited NO production and were expected to be labdane diterpenes, and the active components were characterized via further isolation. The results of the NO production inhibitory assay of the isolated compounds correlated well with the results of bioassay-coupled LC-QTOF MS/MS. Among the identified constituents, NO production inhibitory activities of 16-hydroxy-labda-8(17),13-diene-15,19-dioic acid butenolide (2) and 15-hydroxypinusolidic acid (3) were newly reported. Taken together, these results demonstrated that LC-QTOF MS/MS coupled with NO production inhibition assay was a powerful tool for accurately predicting new anti-inflammatory constituents in the extracts from natural products. Moreover, it provided a potential basis for broadening the application of bioassay-coupled LC-QTOF MS/MS in natural product research.

• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.237-244
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• 1992

In order to observe the infectivity, growth and development and adult morphology of Metorchis orientalis, a total of 40 chicks were experimentally infected with 100 metacercariae respectively, collected from Pseuderasbora larva. The worms of various developmental stages were recovered from chicks at 1.5, 3, 5, 7, 9, 11, 1:k and 21 days after infection, and they were prepared for morphological observations and measurements. All of the worms were found in the gallbladders of chicks, and their recovery rate was 32% in average. The growth of the body was rapid from 9 to 11 days after infection. The genital primordia appeared in 1.5 and 3-day old worms, and ovary and testes were first observed in 5-day old worms. Thereafter, genital organs gradually matured and completed up to 11 days after infection. The adult worm was leaf-like, and possessed a con- voluted tubular seminal vesicle, an ovoid ovary, a sac-like seminal receptacle, 2 lobed-testes and follicular vitellaria. Eggs were $31.9{\times}15.3{\;}\mu\textrm{m}$ in average size, ellipsoid to elliptical in shape and possessed abopercular thickenings. From the above results, it is concluded that M. orientalis grows in sigmoid pattern in chicks, and their genital organs fully matul.e between days 9 and 11. It is also confirmed that a chick is a new definitive host of M. orientalis.