• 제목/요약/키워드: Multi-species

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Structural Isomers and Excited States of HN3

  • Cho, Ji-Eun;Lee, Hee-Soon;Choi, Cheol-Ho
    • Bulletin of the Korean Chemical Society
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    • 제32권10호
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    • pp.3641-3643
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    • 2011
  • Multiconfigurational wavefunctions were adopted to study structural isomers, their isomerization reactions and excited states of $HN_3$. In addition to the known linear isomer, two new structural isomers were found. The three isomers can be classified as sp, $sp^2$ and $sp^3$ hybridized species, respectively. The sp3 hybridized species turned out to be the second most stable. Large reaction barriers among these species prevent thermal isomerizations. A low-lying $^3A'$ exists with a relative energy of 13.5 kcal/mol. Dramatic re-hybridization and bond elongation was found in the first excited $^1A"$.

Plasmopara elegantissima sp. nov. (Oomycota, Peronosporales), a Downy Mildew Species Specialized to Impatiens textori (Balsaminaceae)

  • Choi, Young-Joon;Gorg, Marlena;Shin, Hyeon-Dong;Thines, Marco
    • Mycobiology
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    • 제48권4호
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    • pp.304-312
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    • 2020
  • Over the past 15 years, downy mildew became the most destructive foliar disease in cultivated Impatiens species (Balsaminaceae) worldwide. A previous study had revealed that the causal agent was not Plasmopara obducens (Oomycota, Peronosporales) but Plasmopara destructor on Impatiens walleriana, and Plasmopara velutina on Impatiens balsamina. This hints to a relatively high degree of specialization of Plasmopara on Balsaminaceae. Therefore, it was the aim of the present study to perform multigene phylogenetic analysis and detailed morphological investigation for several Korean downy mildew samples parasitic to cultivated I. walleriana, and I. balsamina, but also to a northeast Asian wild plant, Impatiens textori. It was revealed that I. textori harbors a new species, which is introduced and described here as Plasmopara elegantissima.

Laser Induced Impedance Changes in Hollow Cathode Lamps

  • Byung Chul Cha;Jae Jung Lee;Ki Beom Lee;Hyo Jin Kim;Gae Ho Lee;Hasuck Kim
    • Bulletin of the Korean Chemical Society
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    • 제14권5호
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    • pp.610-614
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    • 1993
  • Laser induced impedance changes in hollow cathode lamps containing sputtered metal atoms have been employed to measure the spectroscopic properties of metal. This technique, known as optogalvanic spectroscopy, has been shown to be a powerful and inexpensive technique for the investigation of atomic and molecular species. Characteristic optogalvanic signals from hollow cathode lamps (HCL) made of different metal species and induced with a pulsed dye laser were observed, and the dependence of the optogalvanic signal on the discharge current and wavelength of laser was measured. Based on the results obtained, the mechanisms involved in evoking the optogalvanic signals were consisted of single-photon absorption, multi-photon absorption, and photoionization. Moreover the current dependence of the optogalvanic signal indicates that the optogalvanic technique could be one of the most sensitive optical methods of detecting atomic species.

Penicillium vietnamense sp. nov., the First Novel Marine Fungi Species Described from Vietnam with a Unique Conidiophore Structure and Molecular Phylogeny of Penicillium Section Charlesia

  • Nguyen, Van Duy;Pham, Thu Thuy
    • Mycobiology
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    • 제50권3호
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    • pp.155-165
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    • 2022
  • Penicillium vietnamense sp. nov. was isolated from Nha Trang Bay, Vietnam in June 2017. It is phylogenetically distinct from the sister species of Penicillium section Charlesia series Indica based on multi-locus sequence typing results using internal transcribed spacer, large subunit ribosomal RNA, b-tubulin, calmodulin, and RNA polymerase II second largest subunit regions. It showed strong growth on Czapek yeast autolysate agar at 37 ℃, a strong acid production on Creatine sucrose agar, and produced short stipes, small vesicles, and subglobose to globose conidia delicately roughened with very short ridges. As the first novel marine fungi species described from Vietnam and discovered in a unique environment, the data could be significant for understanding the taxonomy and geographical distribution of marine fungi in tropical coastal systems such as Vietnam.

Marine Biodiversity Study and Biotechnology Exploitation in China

  • Liu, J.Y.
    • 한국해양바이오학회지
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    • 제1권1호
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    • pp.40-47
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    • 2006
  • Large scale marine biodiversity studies in China have been carried out for more than half a century since the founding of the Institute of Oceanology, CAS, in 1950. Through a series of coastal and multi-disciplinary oceanographic investigations in the shelf seas and biodiversity studies since the late fifties, a total of 20,278 species of marine biota have been recorded upto 1994. Recent intensive studies have further revealed the richness of marine biota of the China seas,a great number of marine species have been found and many new taxa established. The total species number of main biotic groups increased about 50 % of that estimated in 1994. The results have promoted the fast development of China's marine fisheries, medicine (drug) and biodiversity research, and attracted many scientists, particularly bio-technologists, to join their studies. Environmental deterioration and human activity strongly stressed the sustainable development and conservation of marine bio-diversity, and resulted in the increase of end angered species as record ed in the new published ${\ll}$China Species Red List${\gg}$ with the threatened category of species assessed by adopting the new IUCN criteria. To further reveal the high diversity and their history, present status and future of marine organisms existed in the world ocean, an international Project ${\ll}$Census of Marine Life (CoML)${\gg}$ was established in 2000 in the USA. Scientists predicted that 2 to 3 times of numbers of the known species will possibly be found in various marine habitats, particularly the abyssal ocean. The Research Plan and the Projects were briefly introduced, and the relationship between marine biodiversity and biotechnology was discussed. The Project planned to apply new and high techniques and new equipments on board research vessel and in laboratory. Brief review of recent advances of Chinas' marine biodiversity and biotechnology studies indicated that fascinate results have been achcieved; but further effort should be made to promote the continuous advance of our basic researches and their application in related production and maintain sustainable development.

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평림천 어류군집에 관한 연구 - 평림댐 상·하류 수질 및 하천건강성평가와 함께 - (A Study on Fish Community in Pyeonglim Stream - with Water Quality and Stream Health Assessment in Up- and Downstream of Pyeonglim Dam -)

  • 서진원
    • 환경영향평가
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    • 제18권3호
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    • pp.151-160
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    • 2009
  • In order to use fundamental data for conservation of species diversity and stream health with dam development, fish investigation in up- and downstream of Pyeonglim Dam was seasonally conducted in 2007~2008. In addition, data of water qualities, investigated for environmental impact assessment, were used to determine a water quality standard level in Pyeonglim Stream, and it revealed that water environment condition was good in the stream. During the study period, a total number of fish caught from the 4 study sites was 5,449 representing 9 families 25 species, and there were 8 Korean endemic species (32.0%) including Rhodeus uyekii, Squalidus gracilis majimae, and Microphysogobio yaluensis. Two species of Zacco temminckii (37.5%) and Zacco platypus (26.3%) were dominant and subdominant in all sites. There were few individuals of the $2^{nd}$-class endangered species (Sand lamprey, Lampetra reissneri) and the introduced species (Bluegill, Lepomis macrochirus), found in the upstream of the dam. and further investigation for conservation of the endangered species and for prevention of the introduced species is needed in future. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity(IBI) was evaluated and it resulted mostly in good(26~35) and excellent(36~40) condition in all sites. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

다제내성 슈퍼박테리아에 대한 새로운 항생제인 항균 펩타이드 (Antimicrobial Peptide as a Novel Antibiotic for Multi-Drug Resistance "Super-bacteria")

  • 박성철;나재운
    • 공업화학
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    • 제23권5호
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    • pp.429-432
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    • 2012
  • 최근 항생제에 대한 내성이 빠르게 확산됨에 따라 이를 극복하기 위해 새로운 항생제들을 찾기 위한 노력이 많은 연구자들에 의해 이루어지고 있다. 미생물의 외부공격에 대해 모든 생명체들은 방어물질을 분비하거나 내재하고 있는 데 그 중 하나가 항균 펩타이드이며, 전 세계적으로 활발한 연구가 이루어지고 있고 새로운 차세대 항생제로써 인식 되어진다. 이에 본 총설에서는 항균 펩타이드의 미생물에 대한 항생활성, 작용기작과 개발현황에 대해 고찰하고자 한다.

Distribution and Antibiotic Susceptibility Patterns of Genus Mycobacterium at a Private Hospital, Korea

  • Hong, Sung Kyun;Hur, Sung-Ho;Seong, Hee-Kyung
    • 대한의생명과학회지
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    • 제19권2호
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    • pp.132-141
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    • 2013
  • Mycobacterium isolates were retrospectively identified, antibiotics susceptibility test results and basic clinical data were analyzed for the 715, excepted 308 in 1,023 specimens, from a mycobacterial laboratory at a tertiary care hospital from September 2002 to December 2008. Their male to female ratio was 1.12 to 1 (379 male, 336 female). The median age of study population was 47 years (range from 10 to 93 years). Distribution of Mycobacterium species was 90.1% of total were isolates Mycobacterium tuberculosis, and 9.9% of the total non-tuberculosis Mycobacterium isolated, and Among nontuberculosis Mycobacterium isolates, 60.6% were Mycobacterium avium complex, 14.1% were isolates Mycobacterium abscessus, and 12.7% were isolates Mycobacterium intracellulare. Among 526 Mycobacterium tuberculosis isolates, 81.7% isolates were susceptible to first line antibiotics, 18.3% were resistant to one or more antibiotics. Non-tuberculosis Mycobacterium isolates, all were resistant to two or more antibiotics. Multi-antibiotic resistant tuberculosis rate was show 10.2% of total specimens. Isolated Mycobacterium species, 19.2% were multi-antibiotic resistant tuberculosis, and the rate of nontuberculosis Mycobacterium resistant to isoniazid and rifampin was very highly 84.5%. Thus among acid fast bacilli culture positive cases, Mycobacterium tuberculosis and non-tuberculosis Mycobacterium were must exactly identification and antibiotic sensitivity test. It was considered to help to select of the antibiotic in preventive medicine.

제약공단 방류수 유입 하천에서의 항생제 내성 bacteria에 관한 연구 (Study on Antibiotic Resistant Bacteria in Surface Water Receiving Pharmaceutical Complex Effluent)

  • 김영진;김영규
    • 한국환경보건학회지
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    • 제42권6호
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    • pp.409-418
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    • 2016
  • Objectives: The purpose of this study was to characterize penicillin G resistant bacteria in surface water from pharmaceutical complex effluent. Methods: Surface water was sampled from pharmaceutical complex effluent in Gyeonggi-do Province, Korea in March 2015. Water samples were plated in triplicate on tryptic soy agar plates with 32 mg/L of penicillin G. Penicillin G resistant bacteria were selected from the effluent and subjected to 16S rRNA analysis for the penicillin G resistant species determination. Identified resistant strains were tested for resistance to various antibiotics. Results: Penicillin G resistant bacteria were present at 8.0% in terms of culturable heterotrophic bacteria. Identified penicillin G resistant bacteria exhibited resistance to more than nine of the antibiotics studied. These resistant bacteria are gram negative and are closely related to pathogenic species. Conclusion: Multi-antibiotic resistant bacteria in the surface water of pharmaceutical complex effluent suggest the need for disinfection and advanced oxidation processed for pharmaceutical effluent.