• Title/Summary/Keyword: double hosts

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Synthesis of Diazacrown Ethers Containing Phenolic Side Arms and Their Complex with Divalent Metal Ions

  • Chi, Ki-Whan;Ahn, Yoon-Soo;Shim, Kwang-Taeg;Huh, Hwang;Ahn, Jeong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.23 no.5
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    • pp.688-692
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    • 2002
  • The aminomethylation of phenols with para-substituents by the Mannich reaction has successfully been accomplished to produce the Mannich bases 2-6. The compounds 7-8 have also been synthesized in order to identify the effect of the side arms and t he macrocycle in the complex formation. Protonation constants and stability constants of the double armed diaza-18-crown-6 ethers 2-7 with metal ions have been determined by potentiometric method at 25 $^{\circ}C$ in 95 % methanol solution. Under a basic condition (pH > 8.0), the double-armed crown ethers 2-6 revealed stronger interaction with divalent metal ions than the simple diazacrown ether 1. The stability constants with these metal ions were Co 2+ < Ni2+ < Cu2+ > Zn 2+ in increasing order, which are in accordance with the order of the Williams-Irving series. The stability constants with alkali earth metal ions were Ca 2+ < Sr 2+ < Ba 2+ in increasing order, which may be explained by the concept of size effect. It is noteworthy that the hosts 2-6, which have phenolic side arms and a macrocycle, bind stronger with metal ions than the hosts 1 and 7. On the other hand, the host 8, which has phenolic side arms with a pyperazine ring,provided comparable stability constants to those with the host 3. These facts demonstrate that phenolic side arms play a more important role than the azacrown ether ring in the process of making a complex with metal ions especially in a basic condition. In particular, the log KML values for complexation of divalent metal ions with the hosts 2-6 had the sequence, i.e., 2 (R=OCH3) < 3 (R=CH3) < 4 (R=H) < 5 (R=Cl) < 6 (R=CF3). The stability constants of the hosts 5 and 6 containing an electron-withdrawing group are larger than those of the hosts 2 and 3 containing an electron-donating group. This substituent effect is attributed to the solvent effect in which the aryl oxide with an electron-donating group has a tendency to be tied strongly with protic solvents.

Genetic Diversity in the Coat Protein Genes of Prune dwarf virus Isolates from Sweet Cherry Growing in Turkey

  • Ozturk, Yusuf;Cevik, Bayram
    • The Plant Pathology Journal
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    • v.31 no.1
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    • pp.41-49
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    • 2015
  • Sweet cherry is an important fruit crop with increasing economical value in Turkey and the world. A number of viruses cause diseases and economical losses in sweet cherry. Prune dwarf virus (PDV), is one of the most common viruses of stone fruits including sweet cherry in the world. In this study, PDV was detected from 316 of 521 sweet cherry samples collected from 142 orchards in 10 districts of Isparta province of Turkey by double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA). The presence of PDV in ELISA positive samples was confirmed in 37 isolates by reverse transcription- polymerase chain reaction (RT-PCR) method. A genomic region of 862 bp containing the coat protein (CP) gene of PDV was re-amplified from 21 selected isolates by RT-PCR. Amplified DNA fragments of these isolates were purified and sequenced for molecular characterization and determining genetic diversity of PDV. Sequence comparisons showed 84-99% to 81-100% sequence identity at nucleotide and amino acid level, respectively, of the CP genes of PDV isolates from Isparta and other parts of the world. Phylogenetic analyses of the CP genes of PDV isolates from different geographical origins and diverse hosts revealed that PDV isolates formed different phylogenetic groups. While isolates were not grouped solely based on their geographical origins or hosts, some association between phylogenetic groups and geographical origins or hosts were observed.

Efficient Deep-Blue Organic Light-emitting Diodes with Double-Emission Layers

  • Seo, Ji-Hoon;Park, Jung-Sun;Seo, Bo-Min;Lee, Kum-Hee;Park, Jung-Keun;Yoon, Seung-Soo;Kim, Young-Kwan
    • Journal of Information Display
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    • v.10 no.3
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    • pp.107-110
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    • 2009
  • Efficient deep-blue organic light-emitting diodes were demonstrated using 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl doped in double-emission layers (D-EMLs). The D-EML system, which consists of 2-methyl-9,10-di(2-naphthyl)anthracene and 1,4-(dinaphthalen-2-yl)-naphthalene as blue hosts, was employed to broaden the recombination zone and to ensure the good confinement of the holes and electrons. The optimized device showed a peak current efficiency of 4.47 cd/A, a peak external quantum efficiency of 4.09%, and Commission Internationale de L'Eclairage coordinates of (0.16, 0.10).

Notes on Three Species of the Laboulbeniales (Ascomycotina) Newly Collected from Korea (한국산 충생자낭균류의 미기록종에 관하여)

  • Lee, Yong-Bo;Na, Young-Hee
    • The Korean Journal of Mycology
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    • v.27 no.3 s.90
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    • pp.208-210
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    • 1999
  • Three species belong to the genus Laboulbenia were collected on Carabidae (Coleoptera) and Harpalidae (Coleoptera) from several regions of Korea. Laboulbenia anoplogenii Thaxter was collected from Stenolophus quinquepustulatus Widemann. The characters of this species are the fourth layer of receptacle consisted of two or three cells and the distal end of its posterior cell projecting upward. The thalli were produced on posterior and anterior legs of the hosts. Laboulbenia habui Terada was collected from Chlaenius variicornis Bates. This species is characterized by the basal cells of the secondary appendage composed of short-cylindrical cells, arranged alternately on a double row. The thalli were produced from the elytra and anterior abdomen of the hosts. Laboulbenia pallida Thaxter was collected from Anisodactylus signatus Panzer. This species is distinguished from other related species by the rounded tip of perithecium and the outer appendage branched on the basal cell. The thalli were produced on the posterior elytra of the hosts.

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Copepods of the genus Asterocheres Boeck, 1859 (Siphonostomatoida: Asterocheridae) from Korean waters

  • Il-Hoi Kim;Taekjun Lee
    • Journal of Species Research
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    • v.13 no.2
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    • pp.185-254
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    • 2024
  • Sixteen species of Asterocheres collected from the southern and eastern coasts of Korea are recorded. Two species are redescriptions-Asterocheres aesthetes Ho, 1984 and A. siphonatus Giesbrecht, 1897. The remaining 14 new species described are A. geminus n. sp., A. processus n. sp., A. culicis n. sp., A. eurychelatus n. sp., A. scutellatus n. sp., A. spiniventer n. sp., A. fici n. sp., A. serratus n. sp., A. tridentatus n. sp., A. nodulosus n. sp., A. tetraodontis n. sp., A. dokdoicus n. sp., A. exilis n. sp., and A. zodius n. sp. These new species are compared with other known species of the genus mainly based on the character states of 17 selected characters. These characters include the length/width ratios of the caudal ramus and genital double-somite, the number of postgenital lateral setules or spinules on the genital double-somite of the female, the number of segments of the antennule of both sexes, the position of aesthetasc on antennular segments in the female, the relative length of terminal claw of the antenna, the relative length of the oral siphon, the number of segments and the relative length of the mandibular palp, the presence or absence of inner coxal seta on legs 1 and 4, the relative lengths of setae on the exopod of female leg 5, the presence or absence of sexual dimorphisms of swimming legs, and the presence or absence of a secondary aesthetasc on the male antennule. A key to 22 species of Asterocheres known in Korea waters is provided.

Molecular characterization of bacterial endosymbionts of Acanthamoeba isolates from infected corneas of Korean patients

  • Xuan, Ying-Hua;Yu, Hak-Sun;Jeong, Hae-Jin;Seol, Sung-Yong;Chung, Dong-Il;Kong, Hyun-Hee
    • Parasites, Hosts and Diseases
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    • v.45 no.1 s.141
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    • pp.1-9
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    • 2007
  • The endosymbionts of 4 strains of Acanthamoeba(KA/E9, KA/E21, KA/E22, and KA/E23) isolated from the infected corneas of Korean patients were characterized via orcein stain, transmission electron microscopic examination, and 16S rDNA sequence analysis. Double membrane-bound, rod-shaped endosymbionts were distributed randomly throughout both the trophozoites and cysts of each of Acanthamoeba isolates. The endosymbionts of KA/E9, KA/E22, and KA/E23 were surrounded by electron-translucent areas. No lacunae-like structures were observed in the endosymbionts of KA/E21, the bacterial cell walls of which were studded with host ribosomes. Comparative analyses of the 16S rDNA sequences showed that the endosymbionts of KA/E9, KA/E22 and KA/E23 were closely related to Caedibacter caryophilus, whereas the KA/E21 endosymbiont was assigned to the Cytophaga-Flavobacterium-Bacteroides(CFB) phylum. In the 4 strains of Acanthamoeba, the hosts of the endosymbionts were identified as belonging to the Acanthamoeba castellanii complex, which corresponds to the T4 genotype. Acanthamoeba KA/E21 evidenced characteristics almost identical to those of KA/E6, with the exception of the existence of endosymbionts. The discovery of these endosymbionts from Acanthamoeba may prove essential to future studies focusing on interactions between the endosymbionts and the amoebic hosts.

Purification and Immunological Properties of Vitellin, and its Quantitative Changes during Embyrogenesis in the silkworm, Bombyx mori (누에 난황소(Vitellin)의 분리와 면역학적 특성 및 발육에 따른 함량변화)

  • 손기국;문재유
    • Journal of Sericultural and Entomological Science
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    • v.30 no.2
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    • pp.96-104
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    • 1988
  • Vitellin, the major yolk protein of the silkworm, Bombyx mori was pruified, and its immunological properties and the quantitative changes during embryogenesis were studied. The ovary transplantation into male hosts was also carried out to find its effect on the yolk protein synthesis. The pupal vitellogenin and the egg vitellin of Bombyx mori were purified by DEAE-cellulose column chromatography. These two female specific proteins showed the same mobility in the polyacrylamide gel electrophoresis and the same reaction in the double immunodiffusion test. The immunological identity was also observed between the vitellins of Bombyx mori and Bombyx mandarina. The rudimentary ovaries transplanted into the male hosts of silkworms produced eggs without vitellin, indicating that the yolk precursors synthesized in other female organ beyond the ovary were necessary to produce vitellins. The major yolk protein, vitellin was disintegrated and utilized mostly during late stage of embryogenesis. It was different characteristics from the egg specific protein, which was utilized continuously from the early embryonic stage.

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Relationship between Virulence and Cultural Characteristics in Calonectria ilicicola (Calonectria ilicicola의 병원성과 배양적 특성간의 상호관계)

  • Kim, K.D.;Russin, J.S.;Snow, J.P.;Valverde, R.A.
    • The Korean Journal of Mycology
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    • v.26 no.3 s.86
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    • pp.387-395
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    • 1998
  • Mycelial growth, production of microsclerotia and perithecia, and presence of double-stranded RNA were examined in Calonectria ilicicola isolates from several hosts to detect morphological and/or genetic markers for comparison with levels of virulence. Variability in disease severity, production of microsclerotia and perithecia, and mycelial growth was observed across all isolates. None of 35 isolates of C. ilicicola examined contained detectable levels of double-stranded RNA. Disease severity on soybean cultivars correlated positively with production of both microsclerotia and perithecia. Mycelial growth correlated negatively with production of perithecia. Virulence on the cultivars and production of microsclerotia and perithecia were greater in isolates of C. ilicicola from soybean than those from peanut. These results suggest that the ability of isolates to produce microsclerotia and perithecia is a component of inoculum potential. Perithecia production may serve as a useful marker for characterizing virulence or host specialization in this homothallic fungus.

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Flow-based Anomaly Detection Using Access Behavior Profiling and Time-sequenced Relation Mining

  • Liu, Weixin;Zheng, Kangfeng;Wu, Bin;Wu, Chunhua;Niu, Xinxin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.6
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    • pp.2781-2800
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    • 2016
  • Emerging attacks aim to access proprietary assets and steal data for business or political motives, such as Operation Aurora and Operation Shady RAT. Skilled Intruders would likely remove their traces on targeted hosts, but their network movements, which are continuously recorded by network devices, cannot be easily eliminated by themselves. However, without complete knowledge about both inbound/outbound and internal traffic, it is difficult for security team to unveil hidden traces of intruders. In this paper, we propose an autonomous anomaly detection system based on behavior profiling and relation mining. The single-hop access profiling model employ a novel linear grouping algorithm PSOLGA to create behavior profiles for each individual server application discovered automatically in historical flow analysis. Besides that, the double-hop access relation model utilizes in-memory graph to mine time-sequenced access relations between different server applications. Using the behavior profiles and relation rules, this approach is able to detect possible anomalies and violations in real-time detection. Finally, the experimental results demonstrate that the designed models are promising in terms of accuracy and computational efficiency.

A survey on gastrointestinal parasites of Korean water deer (Hydropotes inermis agyropus) in Chungbuk province (충북지역 야생 한국고라니의 내부기생충 감염률 조사)

  • Choe, Seong-Jun;Na, Ki-Jeong;Jee, Cha-Ho
    • Korean Journal of Veterinary Service
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    • v.34 no.3
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    • pp.259-263
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    • 2011
  • Wildlife has been recognized that has important role as reservoir hosts of disease affecting both people and livestocks. However, information intestinal helminths of Korean water deer were limited. We obtained 20 feces from Korean water deers that were transferred to veterinary hospital in Chungbuk National University from May 2010 to June 2011. Parasite ova were collected using saturated zinc sulfate floatation method. Parasite eggs were examined and measured using light microscope. The identification of parasitic eggs was done by morphological characters. The overall infection rate of parasite was 85% (n=17). The eggs were observed as being Nematodirus spp. (n=14), strongyles egg (n=11), Capillaria spp. (n=9), Trichuris spp. (n=7), Eimeria spp. (n=4), Ogmocotyle spp. (n=3), and Strongyloides (n=1). Mixed infection rate was observed as being single 15% (n=3), double 20% (n=3), triple 15% (n=3), quadruple 30% (n=6), and quintuple 5% (n=1). The Ogmocotyle spp. was first reported in Korea.