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        검색결과 1,713

        623.
        2017.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.
        4,000원
        624.
        2017.10 구독 인증기관·개인회원 무료
        Since methyl bromide(MB) has been designated as ozone deplete substance(ODS) by Montreal protocol (1989), many MBalternative fumigants like ethyl formate and phosphine gas were developed and commercialized. Ethyl formate(EF) is an effectiveMB alternative fumigant to control insect pests on imported fresh commodities. It is important to develop a proper evaporationmethod to apply EF on large scale fumigation because EF has a high boiling point(54℃). Recently, concurrent treatment ofethyl formate and nitrogen(EF+N2 treatment) has been newly developed. At preliminary test, EF+N2 treatment showed goodevaporation rate and showed high efficacy on quarantine pests without phytotoxicity on fresh commodities. In this trial, we’veapplied the EF+N2 treatment on imported orange and lemon at pilot scale (0.5m3, 10m3) containers and commercial scale containerto validate efficacy and phytotoxicity. 70g/m3 of EF liquid was applied on orange and lemon by EF+N2 treatment method,and showed 100% mortality on tested insect pest(Tetranychus urticae) without phytotoxicity at 0.5m3 and 10m3 scale fumigationtrials, respectively. At commercial scale trial, EF+N2 treatment also showed 100% efficacy on T. urticae and there was nophytotoxic symptoms on imported orange and lemon fruit. These results indicate that the newly developed EF+N2 treatmenthas a potential as a MB alternative, and can be applied on imported fresh commodities for quarantine and pre-shipment purpose.
        625.
        2017.10 구독 인증기관·개인회원 무료
        The entomopathogenic fungus Metarhizium anisopliae is one of potent biological control agents against a variety ofinsect pests. In this study, we investigated enzyme production of M. anisopliae strains A and B. They produced extracellularenzymes for degrading the epidermis of Monochamus alternatus, a crucial mediator of the pinewood nematode Bursaphelenchusxylophilus. With Q-TOF MS/MS analysis, 29 kDa protein, a major band on a SDS-PAGE gel, was identified as subtilisin-likeserine protease PR1A. M. anisopliae A produced an extracellular enzyme more efficiently than M. anisopliae B: however,enzyme activities targeted for the cuticle were comparable. Our results suggest that the two strains of M. anisopliae havethe biological potential against M. alternatus with insecticidal protease production.
        626.
        2017.10 구독 인증기관·개인회원 무료
        The entomopathogenic fungus Metarhizium anisopliae B is a powerful biological control agent against Monochamusalternatus, a crucial mediator of the pinewood nematode Bursaphelenchus xylophilus. In this study, production of destruxins(dtxs), insecticidal cyclic hexadepsipeptides, was monitored in the submerged culture of M. anisopliae B. Three typesof dtxs, i.e., destruxin A, B, and E, were produced during the culture. Among the three dtxs, the production yield ofdestruxin A was best, followed by destruxin B and E. Destruxin A production was increased when pH was controlledat 6.0, whereas production of destruxin E was not affected by the pH control. The highest yield of dtxs A, B, and Ewere 16.4, 7.3, and 6.1 mg L-1, respectively. Considering that process for dtxs production has not been optimized, M.anisopliae B has more powerful implication as a biocontrol agent.
        627.
        2017.10 구독 인증기관·개인회원 무료
        West Nile Virus (WNV) is transmitted by infected mosquitoes. Vector mosquitoes usually acquire these pathogens fromfeeding on an infected host, and transmit the pathogens to a naive host during feeding events. To understand the virustransmission dynamics and to survey WNV throughout country, the present study has been conducted. We collected mosquitoesat urban parks in Seongnam, Wonju, Gunsan, Daegu, and Tongyeong using CDC light trap with Dry ice from April toSeptemper in 2017 (mosquito collecting is on going). Among collected mosquitoes, blood-fed mosquitoes were conductedblood meal identification assay and the other mosquitoes were subjected to virus detection using real-time PCR method.A total of 2,290 mosquitoes representing 6 genera and 15 species were collected. The most dominant species was Culexpipiens complex (42.1%) followed by Aedes albopictus (15.1%), Ae. vexans nipponii (14.6%), Ochlerotatus koreicus (9.8%),Cx. orientalis (6.5%), and Armigeres subalbatus (4.4%). The blood meal source were of mammal (93.3%), and birds (6.7%).So far, no WNV has been detected in any mosquitoes.
        628.
        2017.10 구독 인증기관·개인회원 무료
        The members of the genus Flavivirus are noteworthy, as they cause infectious diseases in humans, such as Zika, denguefever, yellow fever, West Nile, and Japanese encephalitis. Due to the increased awareness of the public health risk posedby flavivirus-infected mosquitoes, mosquito collections were performed in six urban parks of South Korea, as the parksare designated for human recreation but also provide suitable habitats for mosquitoes. We examined the diversity andabundance of mosquito species and conducted molecular diagnostics for the detection of flavivirus infections. Monthlycollections were carried out in each park from March to August in 2017. A total of 4,851 mosquitoes (5 genera and13 species) were collected using BG-sentinel traps and then investigated for flavivirus infections. Pathogenic flavivirusinfections causing human diseases were not observed in the field-collected mosquitoes. However, insect-specific flavivirus(ISF) infections were detected in several mosquito pools. ISF has been previously known to enhance or suppress the replicationof medically important flaviviruses in co-infected mosquito cells. In this study, partial sequences of ISF were analyzed.However, further studies are needed in order to determine its genetic characterization and biological function in vivo.
        629.
        2017.10 구독 인증기관·개인회원 무료
        This study is investigated the growth characteristics(number of available stipe, pileus diameter, pileus thickness, stipe length, stipe thickness, object weight, comparison yield ability of 1 cycle) and storage characteristics of ‘Sanjo 701’ (S7) cultivars according to relative humidity. The S7 growth characteristics were investigated by quantifying the growth and the characteristics according to the relative humidity, The storage stability was investigated every 5 days and freshness was measured by ‘Minamide Method’. S7 pileus diameter is The higher the relative humidity was confirmed becomes larger and the more increased relative humidity also increase the comparison yield ability of 1 cycle. However, pileus diameter or stipe length This could not see the big difference in the three treatment groups, the plieus thickness was no significant difference in the treatment of 80% and 95%. The fresh weight of S7 decreased significantly at 80% and 95% relative humidity after 10 days of storage, but decreased continuity in 65% humiditiry. The elongation percentage of S7 pileus was observe in 95% relative humidity, values of L, a and b (SCI), showed the highest L value in 65% and the a value in 95%. b values were similar in 65%, 80% and 95% treatments. On the ‘Minamide Method’ measure freshness was changed from the 10th day of storage at relative humidity of 95%, but humidity of 65% and 80% treatments, it changed after 15 days of storage. In this study growth characteristics and yield were increased at higher relative humidity, but storage stability was decreased. Therefore, it is deemed necessary to change the relative humidity to produce high quality mushrooms.
        630.
        2017.10 구독 인증기관·개인회원 무료
        Polygonum multiflorum (Polygonaceae family) is effective to cholesterol lowering effect, increased immunity effect and whitening effect. P. multiflorum root is used for medicinal herb that can be used as raw material for food. In this study, acetic acid fermentation was adding extracts of P. multiflorum root (0%, 1%, 3%, 5%) for the developing healthy beverage. In this study, we investigated the contents of free sugars, organic acids and inorganic components of P. multiflorum root. As a result of free sugars from P. multiflorum root analysis, three kind of free sugars were determined the glucose, sucrose and lactose by HPLC. Four kind of organic acids were found in lactic acid fermented P. multiflorum root. And oxalic acid, lactic acid and succinic acid were detected in organic acids. The content of lactose and lactic acid in lactic acid fermented P. multiflorum root was the highest among the free sugars and organic acids. The content of minerals were in high orders of sodium > calcium > magnesium in P. multiflorum by acetic acid fermentation. The content of inorganic components was highest in lactic acid fermented solution with 5% and proportional to the content of P. multiflorum
        631.
        2017.10 구독 인증기관·개인회원 무료
        The purpose of this study was to expand the utility of the Polygonum multiflorum. Also, we fermented P. multiflorum by mushroom mycelial, and analyzed for chemical compositions and biological active of fermented P. multiflorum root. The crude protein content did not show a significant difference between control and fermented P. multiflorum root, crude fat, ash and crude fiber content of fermented P. multiflorum root were lower than control. The content of soluble nitrogen free extract of P. multiflorum root was significantly higher than fermented P. multiflorum root. The major amino acids of P. multiflorum root were determined the arginine. The content of arginine and glutamic acid were 586.67 mg%, and 283.78 mg%, respectively. Sixteen kinds of amino acids were detected in fermented P. multiflorum root, and the major amino acids were determined the arginine and threonine. The total amino acid contents of control and fermented P. multiflorum root were 3,469.03 mg%, and 3,630 mg%, respectively. As the results of antioxidant activity test, the antioxidant capacity of fermented P. multiflorum had a higher than the control. As the mushroom fermentation progresses, it is confirmed that the amino acid content and antioxidant capacity were increased, and it is expected to develop the product using the fermented P. multiflorum using mushroom mycelials.
        632.
        2017.10 구독 인증기관·개인회원 무료
        NRPS (non-ribosomal pepetide synthetase) plays an important role in the biosynthesis of secondary metabolites, which includes economically important compounds such as antibiotics, antitumor agents, immune-suppressants, siderophores, toxins, etc. In most cases, however, their functions and biosynthesizing pathways have been still remained riddles because of their cryptic expression and recalcitrant genetics. In our previous genome analyses of Cordyceps bassiana C101, we predicted the sequences of secondary metabolite biosynthesizing gene clusters, which contain non-ribosomal pepetide synthetases whose functions are already known such as beauvericin, bassianolide, bassiatin, tenellin, beauverolides, and oosporein. The authors focused on nrps6 that has not been functionally studied. The single-gene deletion and overexpression mutants were established via Agrobacterium-mediated transformations. PCR, quantitative real-time PCR, and southern blot analyses were carried out to confirm the correct single-gene integrated homologous recombination. In further study, comparative metabolic profiling between wild-type and mutant strains will be followed by their detailed chemical structure analysis through NMR spectroscopy.
        633.
        2017.10 구독 인증기관·개인회원 무료
        Polygonum multiflorum (Polygonaceae family) is effective to cholesterol lowering effect, increased immunity effect and whitening effect. P. multiflorum root is used for medicinal herb that can be used as raw material for food. In this study, acetic acid fermentation was adding extracts of P. multiflorum root(0%, 1%, 3%, 5%) for the developing healthy beverage. In this study, we investigated the contents of free sugars, organic acids and inorganic components of P. multiflorum root. As a result of free sugars from P. multiflorum root analysis, three kind of free sugars were determined the glucose, sucrose and lactose by HPLC. Four kind of organic acids were found in lactic acid fermented P. multiflorum root. And oxalic acid, lactic acid and succinic acid were detected in organic acids. The content of lactose and lactic acid in lactic acid fermented P. multiflorum root was the highest among the free sugars and organic acids. The content of minerals were in high orders of sodium> calcium> magnesium in P. multiflorum by acetic acid fermentation. The content of inorganic components was highest in lactic acid fermented solution with 5% and proportional to the content of P. multiflorum
        634.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A karyotype analysis of five wild rose species (Rosa helenae, R. mulliganii, R. multiflora, R. rubus, and R. solieana) was performed using bicolor fluorescence in situ hybridization (FISH). All five species were found to be diploid (2n = 2x = 14). The chromosome length in the metaphase stage ranged from 1.29 to 2.05 μm in R. helenae, 3.32 to 6.82 μm in R. mulliganii, 1.58 to 2.24 μm in R. multiflora, 2.05 to 3.46 μm in R. rubus, and 1.62 to 2.46 μm in R. solieana. The chromosomes were either metacentric or submetacentric, with no subtelocentric or telocentric chromosomes being observed. Each p air of 5 S and 4 5S rDNA sites was detected at the proximal region of the long arm and the terminal region of the short arm of chromosome #7, respectively.
        4,000원
        635.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The Somatic cell nuclear transfer (SCNT) method can be applied to various fields such as species conservation, regenerative medicine, farming industries and drug production. However, the efficiency using SCNT is very low for many reasons. One of the troubles of SCNT is that it is highly dependent on the researcher’s competence. For that reason, four somatic cell nuclear injection methods were compared to evaluate the effect of hole-sealing process and existence of cytochalasin B (CB) on efficiency of murine SCNT protocol. As a results, the microinjection with the hole-sealing process, the oocyte plasma membrane is inhaled with injection pipette, in HCZB with CB was presented to be the most efficient for the reconstructed in SCNT process. In addition, we demonstrated that the oocytes manipulated in Hepes-CZB medium (HCZB) with CB does not affect the developmental rate and the morphology of the blastocyst during the pre-implantation stage. For this reason, we suggest the microinjection involving hole-sealing in HCZB with CB could improve SCNT process efficiency.
        4,000원
        636.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Three bamboo stands(Phyllostachys pubescens(Mazel) Ohwi, P. bambusoides Sieb. et Zucc, P. nigra var. henonis Stapf ex. Rendle) were selected to determine suitable biomass equations and productivity of Gajwa and Wola National Experimental Forests, Jinju, Southern Korea. Different independent variables such as diameter at breast height(DBH) or the combination of DBH and height(H) were used to develop biomass equations(Allometric model : logY = a + blog DBH; Linear-quadratic model : Y=aDBH + bDBH2; Linear model with DBH and height : Y=a + bDBH2·H) for each bamboo component from two age-sequence(current-year, > 1-year-old) of three bamboo stands. Based on statistical indicators, the most suitable equation model to estimate biomass from bamboo stands was a linear-quadratic model. Aboveground biomass of three bamboo stands estimated by the model was 48.864 Mg ha-1 for the P. pubescens, followed by 36.632 Mg ha-1 for the P. bambusoides, and 36.504 Mg ha-1 for the P. nigra var. henonis stands, respectively. The highest biomass in the P. pubescens stand was attributed to the morphological growth characteristics such as DBH and height. Belowground biomass was also highest for P. pubescens(53.35 Mg ha-1), followed by the P. bambusoides(36.73 Mg ha-1) and the P. nigra var. henonis(29.75 Mg ha-1) stands. The results indicate that the morphological growth characteristics such as DBH and height among bamboo species were the most important factor to determine bamboo biomass productivity at a local level.
        4,300원
        637.
        2017.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cockles(Tegillarca granosa) species that found throughout the Indo-Pacific region and this study was conducted in Yeosu from November 2015 through April 2016. Antioxidant activities (lipid peroxidation, DPPH radical scavenging, superoxide anion radical scavenging, reducing power, and iron chelating assays) were studied at different stages during the processing. The results showed that all cockle samples were related to antioxidant activities, they also possessed effective abilities as free radical scavengers, reducing agents, and iron chelators in most cases. Seasonal variations in antioxidant activities were also observed, characterized by high activity values in April, spring season, a period where phytoplankton is their primary food source which propagates considerably. Moreover, the harvested cockles exhibited the higher radical scavenging activities than marketed cockles by compared in the similar concentration and the activities increased with increasing concentration. The results also showed the useful in the assessment of the cockle potential for the development of functional foods, food ingredients or pharmaceuticals. Moreover, keeping the freshness of the cockle during processing chain is pivotal for keeping its antioxidant activities.
        4,000원
        638.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A consumer is an individual entity with various motivations. This study is intended to incorporate a hierarchical structure of motivation to understand self-determined motivation for purchasing secondhand merchandise at thrift stores. A conceptual model adopted from Cadwallader et al. (2010)’s comprehensive model of motivation used in a marketing context was developed to investigate motivational process in secondhand merchandise shopping. The conceptual model includes the three levels of motivational structure–the global, contextual (environmental concern and frugality), and situational motivation. A series of the causal relationships among the three levels of self-determined motivations and buying intention to shop at thrift stores were hypothesized. A total of 219 respondents from two different northeastern state universities in the U.S. completed a self-administered survey. The results indicated that secondhand merchandise shopping is well explained in the hierarchical structure of self-determined motivation where the global motivation had a positive impact on the contextual motivations regarding environmental concern and frugality. Of the two contextual motivations, only environmental concern had a positive impact on situational motivation for shopping at thrift stores. Finally, the situational motivation positively influenced the intention to shop at thrift stores. The results of this model suggest that the hierarchical structure of self-determined motivation would be a very useful framework to understand consumer behavior for apparel shopping. Also, further research can be done to identify other contextual motivational factors to understand consumer motivation for shopping at thrift stores.
        4,500원
        639.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fe-6.5 wt.% Si alloys are widely known to have excellent soft magnetic properties such as high magnetic flux density, low coercivity, and low core loss at high frequency. In this work, disc-shaped preforms are prepared by spark plasma sintering at 1223 K after inert gas atomization of Fe-6.5 wt.% Si powders. Fe-6.5 wt.% Si sheets are rolled by a powder hot-rolling process without cracking, and their microstructure and soft magnetic properties are investigated. The microstructure and magnetic properties (saturation magnetization and core loss) of the hot-rolled Fe-6.5 wt.% Si sheets are examined by scanning electron microscopy, electron backscatter diffraction, vibration sample magnetometry, and AC B–H analysis. The Fe-6.5 wt.% Si sheet rolled at a total reduction ratio of 80% exhibits good soft magnetic properties such as a saturation magnetization of 1.74 T and core loss (W5/1000) of 30.7 W/kg. This result is caused by an increase in the electrical resistivity resulting from an increased particle boundary density and the oxide layers between the primary particle boundaries.
        4,000원
        640.
        2017.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We conduct BVRI and R band photometric observations of asteroid (5247) Krylov from January 2016 to April 2016 for 51 nights using the Korea Microlensing Telescope Network (KMTNet). The color indices of (5247) Krylov at the light curve maxima are determined as B - V = 0:841  0:035, V -R = 0:4180:031, and V -I = 0:8710:031 where the phase angle is 14.1◦. They are acquired after the standardization of BVRI instrumental measurements using the ensemble normalization technique. Based on the color indices, (5247) Krylov is classi ed as a S-type asteroid. Double periods, that is, a primary period P1 = 82:188  0:013 h and a secondary period P2 = 67:13  0:20 h are identi ed from period searches of its R band light curve. The light curve phases with P1 and this indicate that it is a typical Non-Principal Axis (NPA) asteroid. We discuss the possible causes of its NPA rotation.
        4,000원