• 제목/요약/키워드: Molecular evolution

검색결과 530건 처리시간 0.037초

Excitation Energy Transfer Rate Constants in meso-meso Linked Zn(II) Porphyrin Arrays with Energy Accepting 5,15-Bisphenylethynylated Zn(II) Porphyrin

  • Ko, Da-Mee;Kim, Hee-Young;Park, Jin-Hee;Kim, Dong-Ho;Sim, Eun-Ji
    • Bulletin of the Korean Chemical Society
    • /
    • 제26권10호
    • /
    • pp.1505-1511
    • /
    • 2005
  • The excitation energy transfer process occurring in energy donor-acceptor linked porphyrin array system is theoretically simulated using the on-the-fly filtered propagator path integral method. The compound consists of an energy donating meso-meso linked Zn(II) porphyrin array and an energy accepting 5,15-bisphenylethynylated Zn(II) porphyrin, in which the donor array and the acceptor are linked via a 1,4-phenylene spacer. Real-time path integral simulations provide time-evolution of the site population and the excitation energy transfer rate constants are determined. Simulations and experiments show an excellent agreement indicating that the path integration is a useful tool to investigate the energy transfer dynamics in molecular assemblies.

닭 전염성 기관지염 바이러스 한국분리주의 분자생물학적, 역학적 특성 (Molecular and Epidemiological Characteristics of Infectious Bronchitis Virus Isolated in Korea)

  • 송창선;이윤정
    • 한국가금학회지
    • /
    • 제27권2호
    • /
    • pp.91-98
    • /
    • 2000
  • Phylogenetic tree constructed from the nucleotide sequences of the S1 gene showed that the 15 Korean strains of infectious bronchitis virus(IBV) examined were classified into 2 genetically distinct groups, except one respiratory strain, RB86, which was clustered with Massachusetts group. All the 5 respiratory strains belonged to Korean group I and the rest 9 nephropathogenic strains belonged to Korean group II according to the analysis, based on S1 gene sequences. Like previous classifications corresponded with the geographic origin, Korean stains were discriminated from geographically distinct reference strains of IBV. The nephropathogenic strains within Korean group IIsharing 96% homology were continuously isolated since 1990, and seemed to be genetically stable. Whereas the respiratory strains within Korean group Ⅰ sharing 88% homology were sporadically isolate since 1986m and seemed to be genetically unstable. Because we found putative accumulated point mutation as well as recombination events in Korean group Ⅰ, we discussed why genetic variations have often occurred in respiratory strains rather than nephropathognic strains.

  • PDF

Atomic structure of amorphous carbon deposited by various incidence angles -MD simulation study

  • 조민웅;이광렬
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.52-52
    • /
    • 2010
  • Amorphous carbon films have a variety of potential applications. In most such applications film properties are crucial and highly dependent on the film growth conditions. We here investigate the atomic structure of the films, which is generated at various incidence angles, using the classical molecular dynamics. Varying incidence angle of the deposited carbon atoms, different level of sp hybridization and porosity of the film are captured in our model. As the incidence angle becomes glancing, subplantation of the deposited carbon in vertical direction is significantly reduced, rather bouncing back of the incident carbon with slight modification of surface structure is mainly occurred at the early stage of the film growth. As the surface becomes rougher, shadowing effect at these glancing incidences also becomes more significant, which tends to cause asymmetrical and columnar structure. We describe incidence angle dependence of the evolution of the atomic structure of the film and its corresponding properties.

  • PDF

Investigation of adsorption structure for methionine on Ge(100)

  • 양세나;윤영상;박선민;황한나;황찬국;김세훈;이한길
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.369-369
    • /
    • 2010
  • Adsorption and ordering of methionine molecules on Ge(100) surface have been studied using high resolution photoemission spectroscopy and low-energy electron diffraction (LEED) to investigate the adsorption structure as a function of coverage. Analysis of C 1s, S 2p, N 1s, and O 1s core levels reveals quite different according to methionine coverage. We found that the relative population of the two types of thiolates induces a structural change in the ordering from $2\;{\times}\;1$ to $1\;{\times}\;1$. Such an unusual evolution of the methionine adsorption on the Ge(100) surface is discussed in relation to chemical reactions and possible molecular rearrangement on the surface.

  • PDF

아연전기도금의 존착성에 미치는 폴리에탈렌글리콜의 영향 (The Effect of polyethlenglycol on Electrocrystallization of zine Coat)

  • 김현태;정원섭;조남웅
    • 한국표면공학회지
    • /
    • 제30권2호
    • /
    • pp.128-135
    • /
    • 1997
  • The effect of the polyethyledglycol(PEG) on the surface morphology and crystal orientation of electrodeposited zinc from a chloride (1.5M Zinc+7.0M chloriode) have been studied by means of electrochemical methodes, scanning electron microscopy, surface appearance measurement and X-ray diffraction patterns. The resistance of electrodeposit increased, whereas the evolution of hydrogen decreased with incrasing of molecular weight of the PEG. Large grains of electrodeposit were obtained from bath in the absence of organid additive. When the PEG was added, fine grained crystals were observed and the surface roughness was relatively small, but surface appearance deteriorated. The preferred orientation with a(101) plane parallel to the surface was obtained from the PEG addited bath.

  • PDF

Molecular Variation of Endosymbiotic Bacteria Wolbachia in Bemisia tabaci and Related Whiteflies

  • Jahan, S.M. Hemayet;Lee, Kyeong-Yeoll
    • Current Research on Agriculture and Life Sciences
    • /
    • 제30권2호
    • /
    • pp.115-123
    • /
    • 2012
  • Whiteflies harbor several secondary endosymbionts, which are maternally inherited from mother to offspring, that have major effects on host preferences, biology, and evolution. Here, we identified Wolbachia bacteria in sweetpotato whitefly (Bemisia tabaci) as well as whitefly popluations from other countries by comparison of 16S rDNA sequences. Wolbachia were detected in all tested indigenous B. tabaci populations (Bangladesh, Myanmar, Nepal, and the Philippines) as well as Q1 biotype of Korea, whereas they were absent from B biotype of Korea and Q biotype of China. Wolbachia were also detected in all five tested Aleurodicus dispersus populations as well as Tetraleurodes acaciae, whereas they were not detected in all seven Trialeurodes vaporariorum populatuions. In addiiton, Wolbachia were detected in parasitic wasp (Encarsia formosa) of B. tabaci as well as honeybee (Apis mellifera). Among the 19 whitefly populations from different countries, our analysis identified four phylogenetic groups of Wolbachia, thereby demonstrating the high diversity of this genus. Wolbachia phylogeny suggests a correlation of geographical range with ecological variation at the species level.

  • PDF

Prionchulus oleksandri (Nematoda: Mononchida) from Korea

  • Kim, Jiyeon;Kim, Taeho;Ryu, Shi Hyun;Park, Joong-Ki
    • Animal Systematics, Evolution and Diversity
    • /
    • 제34권4호
    • /
    • pp.194-198
    • /
    • 2018
  • The genus Prionchulus Cobb, 1916 represents a group of predaceous nematodes belonging to the family Mononchidae Chitwood, 1937, and is found worldwide. However, only five species have been reported thus far from Korea. Prionchulus oleksandri Winiszewska and Susulovsky, 2003 is reported for the first time from Korea, from sediments collected from the Nakdong River. This species is distinguished from other Prionchulus species by its truncated lip region with small cephalic papillae and refringens vaginae. In this study, morphological characters(detailed morphometrics) of P. oleksandri are described and illustrated using optical microscopy. DNA barcode sequence information (the D2-D3 region of 28S rDNA, 18S rDNA, and internal transcribed spacer rDNA) is also provided for the molecular identification of the species.

DNA Barcoding of Boccardiella hamata (Annelida: Polychaeta: Spionidae) in South Korea

  • Lee, Geon Hyeok;Yoon, Seong Myeong;Min, Gi-Sik
    • Animal Systematics, Evolution and Diversity
    • /
    • 제36권3호
    • /
    • pp.268-273
    • /
    • 2020
  • A spionid polychaete, Boccardiella hamata (Webster, 1879) has been found from mud in crevices between the shells of oysters and adherent substrates in South Korea. The sequences of mitochondrial DNA (mtDNA) cytochrome c oxidase subunit 1 (CO1), 16S ribosomal DNA (16S), and the nuclear 18S ribosomal DNA (18S) from Korean individuals of Boccardiella hamata were determined in the present study. The molecular analysis based on the 18S rRNA gene sequences showed clear separation among the spionid polychaete species, and the sequences of Korean and Japanese individuals are completely identical. The morphological diagnosis and photographs of B. hamata are also provided.