검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 1,386

        504.
        2015.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 다양한 아민기를 가지는 폴리이미드 소재 및 분리막을 제조하여 그들의 구조의 변화에 따른 기체 투과도를 측정하였으며 동력학(Molecular dynamics; MD) 기술을 이용하여 해당 기체의 시간의 변화에 따른 위치와 속도를 계산하여, 기체분자의 동적 특성을 분석하는데 활용하였다. 투과도 측정결과 합성된 고분자 소재의 경우 고분자 내의 free volume을 증가시키는 치환기를 도입시켰을 경우 기체투과도가 증가되었으나 rigid한 구조가 도입된 폴리이미드는 투과도가 감소되는 경향을 확인하였다. 또한 분자동력학 시뮬레이션을 이용하여 기체투과거동 변화를 분석한 결과 실제 기체투과도 측정결과와 유사한 결과를 나타냄을 확인할 수 있었다.
        4,000원
        505.
        2015.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 가축의 유전적 다양성 유지 및 식량 안보에 있어서 재래품종의 중요성은 점차 증대되고 있다. 제주흑우는 멸종위험에 처한 품종이며, 2013년 7월 문화재청에 의해 천연기념물 제546호로 지정되었다. 본 연구의 목적은 제주흑우(124두)의 유전적 다양성, 유연관계 및 유전적 구조의 평가이며, 그 비교 대상으로 한우(128두) 및 외래품종 홀스타인(73두)을 공시하였다. 분자유전학적 특성을 평가하기 위해 11개 초위성체 마커(BM1824, BM2113, ETH10, ETH225, ETH3, INRA23, SPS115, TGLA122, TGLA126, TGLA227, TGLA53)의 대립유전자형을 분석하였으며, 그 결과를 토대로 유전적 다양성 지수들을 산출하였다. 품종별 평균 기대이형접합도(HExp)는 0.605-0.738, 관측이형접합도(HOsb)는 0.667-0.747 그리고 다형정보지수(PIC)는 0.644-0.773의 범위를 보였다. 특히, 제주흑우의 유전적 다양성 지수는 가장 낮은 결과를 보였다. STRUCTURE를 이용한 군락 분석 결과 유전적으로 3개의 군락으로 구분되었으며, 주성성분분석(PCA) 결과 또한 3개의 군집으로 분류됨을 확인하였다. 따라서 본 연구의 결과는 제주흑우의 유전적 고유성 및 유전자원으로써 가치 판단을 위한 과학적 근거가 될 것으로 사료된다.
        4,000원
        506.
        2015.04 구독 인증기관·개인회원 무료
        Cotton aphid infests more than 700 plants and a major pest of various horticultural crops worldwide. The glucose regulated protein 78 (GRP78) is a member of heat shock protein 70. Its expression is associated with the nutritional changes as well as environmental stresses. The full sequences of grp78 cDNA of Aphis gossypii was determined. It had conserved motifs of hsp genes and terminated in KDEL which is common to GRP78. Quantitative realtime PCR showed that its level was changed during development and also upregulated by starvation. However, its level was not much changed by heat stress. The level of grp78 can be use to understand nutritional physiology on insects.
        507.
        2015.04 구독 인증기관·개인회원 무료
        In our previous study with sequenced data from DNA barcoding region of Korean Tettigonia showed that the Jeju population of T. ussuriana (JJ-Tu) more closely related to T. dolichoptera than mainland population of T. ussuriana (ML-Tu) with low genetic distance (0.87-1.05%). In mitochondrial systematics for a eukaryotic organism including orthopteran insects, sequence data from a short mitochondrial DNA fragment should be trait with caution because nuclear mitochondrial pseudogenes (numts) can be unintentionally coamplified when we use universal primers based on a PCR method. In this study, we retried their sequence analysis to avoid coamplication of numts in sequences from cox1 and cox2 genes. and scrutinized each sequence. The molecular evidences (cox1, cox2, and nad1) for Korean species suggest that JJ-Tu is more closely related to T. dolichoptera (0.76-1.23% in cox1; 1.23-1.54% in cox2; 1.01-1.35% in nad1) than ML-Tu (3.77-4.59% in cox1; 3.61-4.76% in cox2; 2.03-3.25 in nad1). The genetic distance of sequence data from cox1 between JJ-Tu and ML-Tu satisfied a requirement for species-distinction by comparing genetic distance between Tettigonia species. Moreover, JJ-Tu is a geographic population of Tettigonia with different morphological traits that is supported with formed a cluster. Although JJ-Tu closely related to T. dolichoptera with low genetic distance, we will determine its taxonomic status through integrative taxonomic study.
        508.
        2015.04 구독 인증기관·개인회원 무료
        A new gregarine species (Eugregarinida: Gregarinidae) was previously reported from daikon leaf beetle, Phaedon brassicae at Daegwallyeong in Korea. Here, we found another novel gregarine species from the striped flea beetle, Phyllotreta striolata (Coleoptera: Chrysomelidae). This paper describes the morphological and molecular-biological characteristics of Gregarine species associated to P. brassicae and P. striolata. The size and body shape at mature trophozoite stage were the main diagnostic characteristics of those species. Gregarines from P. brassicae were bigger size (100um) with square shaped body while Gregarines from P. striolata were slightly smaller size (80um) with egg shaped body. Based on the partial 18S rDNA sequence, gregarine species from P. striolata was grouped in eugregarine and also this new gregarine showed 85% homology that of the reported Gregarina sp. from P. brassicae. However, gut dissection result showed that each species had own gregarine parasite species association. These results were identical in local populations from three surveyed locations. There was positive relationship between infection rates and elevation for gregarine related to P. striolata. Therefore, we suggested that the gregarines and their coleopteran hosts have species-specific interaction via co-evolution.
        509.
        2015.04 구독 인증기관·개인회원 무료
        Root-lesion nematodes, Pratylenchus sp., are recognized as one of the most important plant parasitic nematodes. They infest various crop plants and cause severe root damages which lead to the yield loss of agricultural crops. There are 72 species recorded in the world, but 14 species in Korea. Soil samples were collected from chrysanthemum cultivars in various regions. Morphological and molecular diagnosis firstly recognized two species as Pratylenchus kumamotoensis and P. pseudocoffeae in Korea. Morphologically, P. kumamotoensis characterized by pharyngeal gland lobes overlapping with intestine dorsally. P. pseudocoffeae, which is similar with P. coffeae, but pharyngeal gland lobes are longer than P. coffeae. In molecular diagnosis, nucleotide sequences of D2-D3 region (700-800 bp) within 28S rDNA and ITS region including ITS1, 5.8S and ITS2 (700-1,000 bp) between 18S and 28S rDNA were determined from collected samples. NCBI database comparison of D2-D3 of P. kumamotoensis and P. pseudocoffeae were 99% similar with those of corresponding species, respectively. ITS of P. pseudocoffeae was 99% similar within species. ITS sequence of P. kumamotoensis was firstly determined in this study. Distribution of P. kumamotoensis was only reported in Japan but P. pseudocoffeae is present in Japan and USA. Here we firstly report the presence of these two species in Korea.
        510.
        2015.04 구독 인증기관·개인회원 무료
        The brown soft scales, Coccus hesperidum (Linnaeus, 1758) is one of the most widely distributed species in the family Coccidae. Interestingly, this species shows considerable morphological variation depending upon the geography and host plants. Although, Korean populations also exhibit morphological variation between geographical regions, this species have been regarded as one species without intensive studies. In this study, we performed Neighbor joining analysis of combined data set of Cytochrome oxidase subunit I COI, 18S ribosomal RNA 18S rRNA, 28S ribosomal RNA 28S rRNA and Elongation factor I-alpha EFI-α genes for Korean populations of brown soft scales. The result of molecular analysis indicated that there are three distinct populations in Korea. Among three populations, one population is separated from two populations with 9% of molecular divergence. Based on high level of molecular divergence, we propose a cryptic species of C. hesperidum with description and illustrations of morphology.
        511.
        2015.04 구독 인증기관·개인회원 무료
        The subgenus Nippocallis (Matsumura, 1917) is one of the 10 subgenera of the genus Tuberculatus Mordvilko, 1894. Originally, this subgenus was regarded as an independent genus of the subtribe Myzocallidina by the distinct morphological features and the host plant association with Castanea (Fagaceae). We performed molecular and morphological analyses to determine whether genus Nippocallis belongs to Tuberculatus group. Molecular analysis of the combined data set of Cytochrome Oxidase subunit I COI, Cytochrome B CytB and Elongation Factor I-alpha EF1α indicated that Nippocallis form a sister clade of the genus Myzocallis Passerini, 1860, apart from the genus Tuberculatus. In this contexts, we propose Nippocallis as a separate genus of the subtribe Myzocallidina.
        512.
        2014.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We map two molecular clouds located in the exact anticenter region emitting in the (J = 1-0) transition of 12CO and 13CO using the 3-mm SIS mixer receiver on the 14-m radio telescope at Taeduk Radio Astronomy Observatory. The target clouds with anomalous velocities of VLSR ~ - 20 km s-1 are distinguished from other clouds in this direction. In addition, they are located in the interarm region between the Orion Arm and the Perseus Arm. Sizes of the clouds are estimated to be about 8.6 and 10.8 pc, respectively. The total mass is estimated to be about 4 x 103 M⊙ using CO luminosity of the clouds. Several cores are detected, but no sign of star formation is found according to the IRAS point sources. Their larger linewidths, anomalous velocities, and their location at the interarm region make these clouds more distinguished, though their physical properties are similar to the dark clouds in the solar neighborhood in terms of mass and size.
        4,000원
        513.
        2014.12 구독 인증기관 무료, 개인회원 유료
        Toothbrushes play an essential role in oral hygiene. However, they can be significant in microbial transmission and can increase the risk of infection, since they can serve as a reservoir for microorganisms in healthy, oral-diseased and medically ill adults. This study was conducted to evaluate toothbrush contamination in six toothbrushes donated from four people. Two participants each supplied two toothbrushes - one used in the bathroom and one used in the workplace. The other two people each donated two toothbrushes used in the workplace. Polymerase chain reaction was used to construct a 16S rRNA clone library. Sequences of cloned DNA were compared with those from the reference organisms provided by GenBank. A total 120 clones, representing 20 clones for each toothbrush, were analyzed. They are composed of six pylum, 46 genera and 79 species. The most dominant species were Streptococcus oralis, Streptococcus parasanguinis and Haemophilus parainfluenzae. Enterobacter and Escherichia were recovered from toothbrushes used domestically. Toothbrushes used in the workplace did not contain Enterobacteria.
        4,000원
        514.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucellosis is an important and re-emerging zoonotic disease worldwide. The prevention of human infection is achieved predominantly through the control of brucellosis in agricultural animals, which in turn depends on accurate diagnosis and vaccination. However, conventional serological diagnosis of brucellosis has several limitations, and currently available vaccines for animals have several drawbacks, including the ability to cause infection in humans. Phosphoglycerate kinase (Pgk) is one of the specific proteins reactive with mouse sera in the early stage of Brucella infection, and deletion of the pgk gene in B. abortus strain 2308 resulted in extreme attenuation of this strain in vitro and in vivo. Furthermore, the B. abortus pgk mutant has been used as a live vaccine, and in challenge experiments, it induced protection that was superior to that conferred by commercial strains. In this study, the pgk gene from Brucella abortus 544 was successfully amplified and cloned into a maltose binding protein fusion protein expression vector (pMAL). The recombinant protein was expressed in Escherichia coli DH5α and purified. The immunogenicity of purified recombinant B. abortus 544 Pgk (rPgk) was evaluated by western blot analysis using Brucella-positive mouse sera. rPgk could be used as an antigenic component for future serological tests and potential vaccine development.
        3,000원
        515.
        2014.11 구독 인증기관·개인회원 무료
        The study objectives were to evaluate the aquatic environment of an urban stream using various ecological parameters of biological biomarkers, physical habitat and chemical water quality and to develop a “Multi-metric Eco-Model” (Mm-E Model) for the ecosystem evaluations. The biomarkers of DNA, based on the comet assay approach of single-cell gel electrophoresis (SCGE), were analyzed using the blood samples of Zacco platypus as a target species. The condition factor (CF) as key indicators of the population evaluation indicator was analyzed along with the weight-length relation and individual abnormality. The four metrics of Qualitative Habitat Evaluation Index (QHEI) were added for the evaluations of physical habitat. In addition, the parameters of chemical water quality were used as eutrophic indicators. Our results suggested that attributes of biomarkers and bioindicators in the impacted zone (Iz) had sensitive response largely to the chemical stress (eutrophic indicators) and also partially to physical habitat quality, compared to the those in the control zone. Hereafter, applying Multimetric Eco-Model to stream ecosystem, it will be able to evaluate ecological health state.
        516.
        2014.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We study the physical and chemical properties of the molecular clump hosting a young stellar cluster, IRAS 20160+3636, which is believed to have formed via the “collect and collapse” process. Physical parameters of the UC Hii region associated with the embedded cluster are measured from the radio continuum observations. This source is found to be a typical Galactic UC Hii region, with a B0.5 type exciting star, if it is ionized by a single star. We derive a CN/HCN abundance ratio larger than 1 over this region, which may suggest that this clump is being affected by the UV radiation from the Hii region.
        4,000원
        518.
        2014.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        New precursors, poly(acrylonitrile-co-crotonic acid) (poly(AN-CA)) and poly(acrylonitrile-co-itaconic acid-co-crotonic acid) (poly(AN-IA-CA)) copolymers, for the preparation of carbon fibers, were explored in this study. The effects of comonomers with acidic groups, such as crotonic acid (CA) and/or itaconic acid (IA), on the stabilization of nanofibrous polyacrylonitrile (PAN) copolymers were studied. The extent of stabilization, evaluated by Fourier transform infrared spectroscopy, revealed that the CA comonomer could retard/control the stabilization rate of PAN, in contrast to the IA comonomer, which accelerated the stabilization process. Moreover, the synthesized PAN copolymers containing CA possessed higher Mv than those of the IA copolymers and also showed outstanding dimension stability of nanofibers during the stabilization, which may be a useful property for improving the dimensional stability of polymer composites during manufacturing.
        4,000원
        519.
        2014.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        분자 동력학(Molecular dynamics; MD) 전산모사 기술은 대상이 되는 입자(일반적으로, 원자)의 위치와 속도를 계산하여, 원자 및 분자들의 다양한 구조 및 동적 특성을 분석하는 데에 있어서 매우 유용한 기술이다. 기체 분리막 연구에 있어서도 MD는 그동안 free volume 분석, conformation search 등과 같은 고분자 구조 분석 및 permeability, diffusivity와 같은 기체 투과 거동을 연구하는 데 널리 사용되어 왔다. 본 총설에서는 기체 분리막 분야에 MD를 적용하는 일반적인 방법론에 대하여 서술하고, 다양한 관련 연구들을 소개하고자 한다.
        4,000원
        520.
        2014.10 구독 인증기관·개인회원 무료
        Recently, researches of molecular biology for the identification of root-knot nematode (RKN) species have been reported in plant quarantine. In this study, applicable and reproducible method to extract high quality genomic DNA from single nematode (Meloidogyne spp.) was developed. Also, the modified method was verified by DNA manipulation techniques such as PCR amplification and cloning. Single juvenile was floated in a drop of water and digested with proteinase K for 24 h. After that, DNA was extracted by using distilled water as extraction buffer. PCR amplification was carried out with universal primers spanning the internal transcribed spacer (ITS) region to distinguish species. When using the existing DNA detection method, quantification results showed that 42.86% of the deposited DNA was extracted. Whereas the modified DNA extraction method was increased to 100%. When PCR products test the direct sequencing using the ITS rDNA primers, it was also identified as M. javanica, M. incognita, and M. hispanica. Based on the studies conducted, the application of this modified method would be useful and efficient on plant parasitic nematode molecular assay.