• Bulletin of the Korean Chemical Society
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• 제20권12호
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• pp.1428-1432
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• 1999

[Fe$^{II}$(BLPA)DBCH]BPh₄ (1), a new functional model for the extradiol-cleaving catechol dioxygenases, has been synthesized, where BLPA is bis(6-methyl-2-pyridylmethyl)(2-pyridylmethyl)amine and DBCH is 3,5-di-tert-butylcatecholate monoanion. ¹H NMR and EPR studies confirm that 1 has a high-spin Fe(II) (S = 2) center. The electronic spectrum of 1 exhibits one absorption band at 386 nm, showing the yellow color of the typical [Fe$^{II}$(BLPA)] complex. Upon exposure to O₂, 1 is converted to an intense blue species within a minute. This blue species exhibits two intense bands at 586 and 960 nm and EPR signals at g = 5.5 and 8.0 corresponding to the high-spin Fe(III) complex (S = 5/2, E/D = 0.11). This blue complex further reacts with O₂ to be converted to (μ-oxo)Fe$^{III}_2$ complex within a few hours. Interestingly, 1 affords intradiol cleavage (65%) and extradiol cleavage (20%) products after the oxygenation. It can be suggested that 1 undergoes two different oxygenation pathways. The one takes the substrate activation mechanism proposed for the intradiol cleavage products after the oxidation of the $Fe^II\;to\;Fe^{III}$. The other involves the direct attack of O₂ to $Fe^{II}$ center, forming the $Fe^{III}$-superoxo intermediate which can give rise to the extradiol cleavage products. 1 is the first functional Fe(II) complex for extradiol-cleaving dioxygenases giving extradiol cleavage products.

• 한국어병학회지
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• 제34권2호
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• pp.133-140
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• 2021

With the recent isolation of a new betanodavirus in shellfish, Korean Shellfish Nervous Necrosis Virus (KSNNV), it has also been identified the reassortant KSNNV of two RNA segments, in which one segment is KSNNV genotype but the other one is known genotype. In this study, we confirmed that the ressortant KSNNVs obtained in previous screening study of our laboratory for betanodaviruses in shellfish were KS/RGNNV and RG/KSNNV type by performing two consecutive multiplex RT-PCR on each RNA1 and RNA2 segment (R1- and R2-discriminative multiplex two-step RT-PCR, respectively) to determine the genotype of each segment based on the size of amplicon. In the pathogenicity analysis, none of the reassortants induced specific external symptoms or mortality of VNN, but viruses of 2 × 10⁴~10⁵ copies/mg or more were detected at 14 days after injection (10⁷ copies/fish) in brain tissues of 4 species except for crucian carp and common carp among the 6 species of juvenile fish used. In addition, the histopathological features of weak but distinct vacuole formation were also found in the brain of these infected fish, but no difference was found between the two reassortants KS/RGNNV-KG and RG/KSNNV-CM.

• Animal Systematics, Evolution and Diversity
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• 제28권1호
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• pp.68-70
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• 2012

A sterrhine species, Perixera punctata (Warren) is reported for the first time from Korea. One male and one female were collected from Jeju Island, South Korea. Perixera punctata can be distinguished by the long bipectinate male antennae, the blackish discal dot and a large dark grayish dot on the subcosta of the forewings and a large dark brownish discal dot and blackish undulating postmedial line on the hindwings. In the male genitalia, a long slender valva with two arm-shaped costal processes is a distinguishing character. In the female genitalia, long and medially twisted ductus bursae with a colliculum, and large, ovate corpus bursae with minute dots are distinguishing characters. Diagnosis and description of the species are given with figures of the male and female genitalia.

• Animal Systematics, Evolution and Diversity
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• 제32권1호
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• pp.21-27
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• 2016

The solitary wasp genus Phimenes (Hymenoptera: Vespidae: Eumeninae) was reported to occur in Vietnam by , represented by one taxon, Phimenes flavopictus continentalis (Zimmermann), which was synonymized under nominotypical Phimenes flavopictus by . A note on gender of this genus is made in the text. One more species, Phimenes indosinensis is recorded in this study from Dak Lak in the southern and Son La in the northwestern parts of Vietnam for the first time. Detailed descriptions of the female and male of the latter are provided with figures. A key to the two species from Vietnam is also provided.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.191.2-191.1
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• 2003

Phyllanthus ussuriensis Rupr. et Maxim. (Euphorbiaceae) has long been used in folk medicine to treat kidney and urinary bladder disturbances, intestinal infections, diabetes, and hepatitis. Reported chemical constituents of this species are one flavonoid (rutin), two gallotannins (gallic acid, methyl gallate) and two ellagitannins.An investigation of the n-BuOH fraction of P. ussuriensis led to the isolation of two new megastigmane glycosides, 10-hydroxy-4,7-megastigmadiene-3-one-9-O-b-D-glucopyranoside (1), 10- hydroxy-4,6-megastigmadiene-3-one-9-O-b-D-glucopyranoside (2) and two known compounds roseoside (3) and 3-oxo-a-ionol-9-O-b-D-glucopyranoside (4). (omitted)

• 원예과학기술지
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• 제33권6호
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• pp.869-876
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• 2015

Wild relative species of domesticated crops are useful genetic resources for improving agronomic traits. Cytogenetic investigations based on chromosome composition provide insight into basic genetic and genomic characteristics of a species that can be exploited in a breeding program. Here, we used FISH analysis to characterize the ploidy level, chromosome constitution, and genomic distribution o f 5S and 4 5S r ibosomal DNA (rDNA) in four wild Cucurbitaceae species, namely, Citrullus lanatus (Thunb.) Mansf. var. citroides L. H. Bailey (2n = 22), Melothria japonica Maxim. (2n = 22), Sicyos angulatus L. (2n = 24), and Trichosanthes kirilowii Maxim. (2n = 66, 88, 110 cytotypes), collected in different areas of Korea. All species were diploids, except for T. kirilowii, which included hexa-, octa-, and decaploid cytotypes (2n = 6x = 66, 8x = 88, and 10x = 110). All species have small metaphase chromosomes in the range of $2-5{\mu}m$. The 45S rDNA signals were localized distally compared to the 5S rDNA. C. lanatus var. citroides and M. japonica showed one and two loci of 45S and 5S rDNA, respectively, with co-localization of rDNA signals in one M. japonica chromosome. S. angulatus showed two co-localized signals of 5S and 45S rDNA loci. The hexaploid T. kirilowii cytotype showed five signals each for 45S and 5S rDNA, with three being co-localized. This is the first report of hexaploid and decaploid cytotypes in T. kirilowii. These results will be useful in future Cucurbitaceae breeding programs.

• 한국조경학회지
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• 제28권1호
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• pp.48-53
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• 2000

This study was carried out to investigate the growth characteristics and propagation methods of Prunus species as woody landscape plants. Both the flowering time and the survival rate of grafting were investigated. The results are obtained as follows: The total of flowering period of Prunus species in Kyonggi province area lasted for about 26 days. The flowering time of the species overlaps. These observations suggest that the possibility of interspecific pollination among Prunus species is very high in the kyonggi province area. The total number of flowers in the species in area was in as follows decreasing order : (1) Prunus yedoensis >Prunus pendula var. ascendens > Prunus subhitella > Prunus sesrulata for. fugenzo > Prunus leveillenana var. pendula. The number of carpels in each flower ranged from 0.3 for Prunus subhirtella to 1.8 for Prunus serulata for. fugenzo. In the caseof Prunus sesrulata for. fugenzo, the carpels appeared to be degenerated and thus losted their function. However, there exist two tyoes of Prunus subhirtella. While one type had normal carpel, the other had the degenerated one. The survival rate of grafting was investigated on May 19. Eighty there percent of the plants survived when the grafting was made in the greenhouse in January whereas the plants grafted in nursery in March survived less in that Prunus suhirtella showed 64%, Prunus leveilleana var. pendula 47%, Prunus sesrulata for. fugenzo 43%, Prunus yedoensis 62% and Prunus pendula var. ascendens 24%, respectively. Therefore, it suggested that high humidity and optimal temperature appeared to incase the survival rate of the grated plants. We therefore propose here that grafting should be done in the greenhouse that both humidity and temperature could be controlled to enhance the efficiency of grafting. This will enable as to perform grafting in winter as well.

• 환경정책연구
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• 제1권1호
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• pp.1-24
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• 2002

Due to the recent increase in greenhouse gases in atmosphere, world climate is rapidly changing and in turn, the earth ecosystem responds upon the climate changes. Comparing the ecosystem in the past, the present shapes of ecosystem is the result of the serious modification. Fishery resources in marine ecosystem, which usually occupy the upper trophic level, are also inevitable from such changes, because they always react to the natural environmental conditions. The northwestern Pacific is the most productive ocean in the world producing about 30% of world catch. From time to time, however, it has been notified that abundance, distribution and species composition of major fish species were altered by climate events. Furthermore, primary productivity of the ocean is not stable under the changing environments, so that carrying capacity of the ocean varies from one climate regime to another. Major climate events such as global warming, atmospheric circulation pattern, climate regime shift in the North Pacific, and El Nino event in the Pacific tropical waters were introduced in relation to fisheries aspects. The current status and future projection of fishery production was investigated, especially in the North Pacific including Korean waters. This new paradigm, ecosystem response to environmental variability, has become the main theme in marine ecology and fishery science, and the GLOBEC-type researches might provide a solution far cause-effect mechanism as well as prediction capability. Ecosystem management principles for multi-species should be adopted for better understanding and management of ecosystem.

• 한국응용곤충학회지
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• 제33권1호
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• pp.39-50
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• 1994

한국산 날개응애류의 분류에 관한 연구중에 1신속 5신종과 5종의 한국미기록종이 밝혀졌기에 보고하는 바이다. 신속은 파도날개응애속(Kpreoribates), 5신종은 한국파도날개응애(koreoribates filia-tus), 지리산인왕응애(Hermannia neotricha), 건지산도포소매응애(Xyobates geonijensis), 성오민동정응애(defectamerus sungohi), 긴털뚜껑응애(Protorpoda flagellata)이며 신아종은 흑달걀응애(Liacarus gammatus coreanus)이고 미기록종은 북바달걍응애(Liacarus polychothomus), 갑옷뿔염주응애(Tecto-damaeus armatus), 등줄뿔염주응애(T,striatus), 머리뚜껑응애(Oripoda trilabiata), 흑팔자기게응애(Do-metorina tuberculata)등이다. 아울러 달걍응애속의 한국종, 민동정응애속, 이리뚜껑응애속(신칭의)검색표를 작성하였고 숭산달걍응애의 오기재를 바로잡았다.

• ALGAE
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• 제28권2호
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• pp.161-171
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• 2013

A morphologically distinct lineage within the Bostrychia moritziana-B. radicans species complex is described as a new species. Bostrychia anomala has thalli with branched monosiphonous filaments with apical cell divisions. The species has terminal tetrasporangial stichidia, each subtending cell bearing tetrasporangia with 2 cover cells. Discharged spores divide transversely, the lower cell first forming a narrow rhizoid and the upper cell forming a monosiphonous shoot. Females have subterminal procarps and males have terminal spermatangial stichidia. Carposporophytes are spherical. Isolates in culture show a pattern of cell death not associated with injury, reminiscent of programmed cell death. Bostrychia anomola shows cell death at intervals along the filaments resulting in division of adjacent cells on either side of the dead cell re-joining the filament; cell division of only one adjacent cell resulting in branching at that site; or filaments fragmenting at the cell death point with adjacent cells forming new apical cells, a means of thallus propagation. The cell death pattern could be a method of filament propagation in the mangrove environment where sexual reproduction is rare.