검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 499

        181.
        2013.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This experiment was carried out to determine the effect of different spectrum conversion greenhouse films (red, blue, red+blue) to changing microclimate and subsequent effect on growth and quality of lettuce (Lactuca sativa L.), tomato (Solanum lycopersicum L.), and melon (Cucumis melo L.) Transmission of PAR (photosynthetic active radiation, 400-700 nm) under red, blue, and blue+red (BR) films was higher by 7.2, 7.6, and 5.8%, respectively, as compared with control greenhouse film. Light transmission in the 300-1100 nm wave band was 91.6% and 91.3% under red and blue films, respectively, compared to 86.4% under control film. Mean daytime temperature in greenhouse was slightly higher in red and blue film and mean night time temperature was higher in BR film. There were no significant differences in relative humidity among the films. Number of leaves and plant fresh weight of lettuce were higher under BR film. Total number of marketable tomato fruits was greater under blue and BR film and fruit weight was heavier under red and blue film compared to control film. Under BR and red film melon fruit weight was increased by 140 g and 80 g respectively, as compared to control film. Sugar content in melon and tomato fruits was not affected by covering films.
        4,000원
        182.
        2012.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        전해정련을 이용한 폐 피복관 처리의 타당성을 살펴보기 위하여, 500℃의 LiCl-KCl 용융염 내에서 표면이 산화된 10 g 규모의Zircaloy-4 피복관 및 순수한 Zircaloy-4 피복관의 전기화학적 거동을 살펴보았다. 산화된 Zircaloy-4 피복관이 담긴 basket을 작업전극으로하여 전압-전류 관계를 측정한 결과, 산화되지 않은 Zircaloy-4 피복관과 비교해 Zr의 산화 peak는 Ag/AgCl 기준전극 대비, 약 -0.7 V ~ -0.8 V로 유사한 반면, 산화 전류의 크기는 확연하게 감소하는 것으로 나타난다. 이러한 결과는 -0.78V의 일정전위를 가한 전기화학적 용해 실험에서 살펴본 전류-시간 곡선에서도 유사하게 나타나며, 피복관 조각들의 평균 두께 및 무게 변화로부터 확인할 수 있다. Zircaloy-4 피복관이 산화되었을 경우, 표면의 산화막이 피복관의 전도성에 영향을 주어 basket 내 위치에 따라 전기화학적 용해의 균일성 및 속도를 떨어뜨리는 것으로 나타나지만, 표면의 미세한 결함과 Zr 산화물의 상 특성으로 인해 전기화학적 용해가 진행되는 것으로 판단된다.
        4,000원
        184.
        2012.06 구독 인증기관·개인회원 무료
        Setdb1/Eset, a histone lysine methyltransferase, is recruited by various transcription factors to modify local chromatin. The observation that Setdb1-null blastocysts fail to produce epiblast-lineage cells suggests a role for Setdb1 in generating mouse embryonic stem cells (mESCs). When examined in mouse zygotes, Setdb1 proteins appeared as dots at perinucleolar rims of pronuclei, with the dot-shaped signals more prominent in male pronuclei. Setdb1 signals were observed diffusely in the nucleus from the two-cell stage onward and, by the blastocyst, took a punctate form, away from nucleolus. Such varying expression patterns suggest its involvement in diverse biological processes at preimplantation stage. Setdb1 appeared in Oct4-positive cells of inner-cell-mass origin but not in trophectoderm-lineage cells in blastocyst outgrowths. Setdb1 co- immunoprecipitated with Oct4 in mESCs, and Setdb1 expression was markedly reduced upon retinoic acid- induced differentiation. These observations suggest that Setdb1 has an important role in maintaining the self-renewal of mESCs through collaboration with Oct4.
        185.
        2012.06 구독 인증기관·개인회원 무료
        Microtubule-associated protein 1B (MAP1B), a member of MAP1 family, plays a key role in the brain development. MAP1B binds to many kinds of proteins directly or indirectly. In our previous studies, MAP1B and glyceraldehydes 3-phosphate dehydrogenase (GAPDH) were down-regulated in bovine follicular cystic follicles (FCF). This study was performed to examine interaction between MAP1B and GAPDH in bovine follicles using immunoprecipitation (IP) with western blot analysis and immunohistochemisty. MAP1B and GAPDH mRNA expression levels were down-regulated in bovine FCFs. Consistent with the semi-quantitative PCR data, their protein expressions were also down-regulated in FCFs. IP data showed that MAP1B bound to GAPDH in normal follicles, but their binding was absent in FCFs, suggesting that these data might be resulted from a low level of MAP1B and/or GAPDH expression. These results suggest that GAPDH does not as always function as a loading control in bovine follicles.
        186.
        2012.05 구독 인증기관·개인회원 무료
        Sweet potato whitefly (SPW), Bemisia tabaci, is the most serious pest of greenhouse tomato as a vector of tomato yellow leaf curl virus since 2008 in Jeju. This study was conducted for within-plant distribution of SPW nymphs on leaves and the characteristic of spatial distribution of SPW adults using by yellow-color sticky trap in greenhouse-grown tomato plants. The nymphs of SPW were mainly distributed on leaves of mid-lower stratum in three stratum of tomato plant. They were also more distributed on three to four leaflets from basal part in a leaf. Ten plots and three plants per plot were appropriated to estimate of mean density of SPW nymph using by visual inspection in a tomato greenhouse. The more SPW adults were caught on horizontally placed sticky trap above 50~80 cm than vertically placed sticky trap above tomato canopy. The horizontal direction trap should be placed in opened site. SPW adults were shown the aggregated distribution pattern using by Taylor’s power law (TPL) and Iwao’s patchiness regression (IPR) model which are commonly used for spatial distribution pattern analysis. TPL was showed better description than IPR for spatial distribution pattern of SPW adults. The required number of trap tended to decrease according to increase the mean density of SPW adult
        188.
        2012.03 구독 인증기관 무료, 개인회원 유료
        House dust mite (HDM) allergens have been associated with allergic diseases, such as asthma, allergic rhinitis, and atopic dermatitis. Various acaricidal agents have been suggested for control of house dust mites; however, their remains act as allergens even after death. Therefore, for avoidance of allergen, expelling the mites is a more effective policy than killing them. In this experiment, we compared the repellent effect of two essential oils (Matricaria chamomilla, Lavandula vera) against house dust mites, Dermatophagoids farinae and D. pteronyssinus in bed fabric. The essential oils were applied by direct contact method at various doses (0.1, 0.05, 0.025, 0.0125, and 0.00625 μl/cm2 and at various exposure times (30, 60, 120, 180, and 240 min). Results of this experiment suggest that the two oils have significant repellent activity. Camomile essential oil in 0.0125 μl/cm2 at 240 minutes had a repellent effect of 93.7% and lavender essential oil in 0.05 μl/cm2 at 180 minutes had a repellent effect of 88.9%. The results of this study showed that camomile essential oil has more potent repellent activity than lavender essential oil at a particular concentration.
        4,000원
        190.
        2011.10 구독 인증기관·개인회원 무료
        Gene targeting is a genetic technique that utilizes homologous recombination between an engineered exogenous DNA fragments with the endogenous genome of an organism. In domestic animal, gene targeting has provided an important tool for producing Knock-out pig for GGTA1 gene to use xenotransplantation. The frequency of homologous recombination is a critical parameter for the success of gene targeting. The efficiency of homologous recombination in somatic cells is lower than that in mouse ES cells. So the application of gene targeting in somatic cells has been limited by its low efficiency. Recently, knock-out rat and mouse was generated by introducing nonhomologous end joining (NHE)-mediated deletion or insertion at the target site using zinc-finger nucleases (ZFN). Therefore, the development of effective knock-out and knock-in techniques in domestic animal is very important in biomedical research. In this present study, we investigated whether homologous recombination events occurs at cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) gene locus using ZFN in porcine primary fibroblast. CMAH-targeted ZFN DNA and mRNA were purchased from SIGMA-Aldrich. CMAH neo targeting vector consists of the neomycin resistance gene as a positive selectable marker gene, 789 bp 5’ arm and 763 bp 3’ arm from Exon 8 of CMAH gene. For transfection, the targeting vector and ZFN DNA or mRNA were introduced into ear fibroblasts cells of Chicago miniature pig by electroporation. After selection of G-418, PCR analysis was performed using 213 colonies transfected with ZFN DNA or mRNA. As a result, 39 positive colonies were identified in colonies transfected with ZFN DNA or mRNA. To our knowledge, this study provides the first evidence that the efficiency of gene targeting using ZFN was higher than that of conventional gene targeting in the porcine fibroblast. These cell lines may be used in the production of CMAH knock-out for xenotransplantation.
        191.
        2011.10 구독 인증기관·개인회원 무료
        Covalent modifications of histone tails have fundamental roles in chromatin structure and transcriptional activity of a target locus. One of such modifications, Methylation at Lysine 9 of histone H3 (H3-K9) causes several epigenetic phenomena including heterochromatin formation, transcriptional regulation and DNA methylation. Setdb1, H3-K9 specific histone methyltransferase, functions in gene silencing, heterochromatin formation and essential role for early development. Here, we demonstrate that Setdb1 associates with promyelocytic leukemia (Pml) protein from the early stage of mouse development and is a constitutive member of PML nuclear bodies (PML-NBs) that have been linked to many cellular processes such as apoptosis, DNA damage responses, and transcriptional regulation. Immunostaining of mouse blastocyst showed that Setdb1 and Pml signals were scattered in nucleus as a few speckles and microinjected Pmlmyc signals colocalize with Setdb1 signals. This colocalization was observed in mEF and the punctate signals of Setdb1 were observed to be present in every nucleus of mEFs and dividing cells with condensed chromosomes. Arsenic treatment, which induces Pml degradation, also caused Setdb1 signals to disappear. Setdb1 knockdown resulted in disassembly of PML-NBs and immunoprecipitation results demonstrated physical interactions between Setdb1 and Pml. These data suggest that Setdb1 was associated in PML-NB and Setdb1 has important function in maintenance of PML-NB structure.
        192.
        2011.10 구독 인증기관·개인회원 무료
        Entomopathogenic fungus Aschersonia aleyrodis naturally occurred on citrus whitefly, Dialeurodes citri nymph was often observed in organic citrus orchards, Jeju. The genus Aschersonia is also known to be toxic against scale insects and other pests. However, little is known about artificial media for mass production of spores of Aschersonia species. Grains are excellent sources of media for mass conidia production of various entomopathogenic fungi. The yeast extract, which converts carbohydrates to carbon dioxides and alcohols, contains a large amount of vitamin B complexes which facilitate the carbohydrate metabolism. The more yeast extract content the more conidia production on artificial medium made from commercial corn flour and corn gluten feed. The number of conidium produced on oat, millet, sorghum, and unhulled barley medium containing 1% yeast extract were 1.8, 1.8, 1.6, and 2.1×1010/plate (90mm × 15mm), respectively. However, the greatest yeast effect among four media showed appeared on sorghum medium, which produced 25 times higher spore production than sorghum alone. Furthermore, the conidia from solid sorghum medium could be easily harvested with cell scraper.
        193.
        2011.10 구독 인증기관·개인회원 무료
        Aschersonia aleyrodis was well-known to be a biological control agent for citrus whitefly, Dialeurodes citri. This entomopathogenic fungus is naturally occurred in organic farming citrus orchards in Jeju. Both lime-sulfur and Bordeaux mixtures are extensively used today to control citrus diseases like citrus melanose and citrus scab, especially in organic farming pest management program. The high concentrated lime-sulfur is also used for pest control such as pink citrus rust mite and scale insects. This study was focused to test the conidial germination and sporulation of Aschersonia aleyrodis on potato dextrose agar (PDA) medium containing different concentrations of two fungicides. The conidia of Aschersonia aleyrodis grown on PDA mixed with commercial bordeaux mixtures, CM150-505, at dilution rate 1:200 (water : bordeaux mixture) were well-germinated but not sporulated at all. On the other hand, Aschersonia aleyrodis did not sporulate and germinate on lime sulfur treated PDA medium even at extremely low dilution rate 1:2,048,000 (water : lime sulfur). However, when the mycelial cells grown at 25o C for at least 7 days at soluble starch-tryptone medium were added to PDA, they were well-sporulated even at high dilution rate 1:100 (water : lime sulfur). This result suggested that the spore mixtures of Aschersonia aleyrodis should be applied to field quite long after lime-sulfur spray.
        194.
        2011.10 구독 인증기관·개인회원 무료
        Riptortus clavatus is one of the most serious pests affecting the cultivation of sweet persimmon, which is one of the most important export fruits in Korea. A pheromone-baited trap has been used in attempts to control this pest. Although the trap showed relatively good trap efficacy, it was often observed that R. clavatus walks around and rests on the surface of the trap rather than entering the trap. In the present study, the development of a more efficient pheromone-baited trap for R. clavatus was pursued by investigating 3 different traps: the fish trap, the pyramidal trap, and the symmetry trap. The fish trap captured the lowest number of R. clavatus, and the pyramidal trap showed moderate capture efficacy. Significantly greater numbers of R. clavatus adults were captured in the symmetry trap. Significantly increased trapping efficacy of the symmetry trap would be useful for mass trapping of R. clavatus.
        195.
        2011.10 구독 인증기관·개인회원 무료
        Beet armyworm (BAW), Spodoptera exigua (Hübner), is a polyphagous lepidopteran pest mainly distributed in tropical and subtropical regions. BAW are known to migrate long distances to find suitable host plants and environmental condition. The possibility of its overwintering in temperate regions has been suspected. This study was conducted for investigating overwintering and phenology of BAW using by sex pheromone trap in Jeju during 2007 to 2011. BAW was able to overwinter at pupae stage regardless of temperature of winter season in Jeju. The times of BAW caught first on traps were different by surveyed years - early March in 2007, middle March in 2008 and 2011 and early April in 2009 and 2010. The times of BAW caught on trap tended to be more dependent on temperature variation during on November and December than on mean temperature of winter season. The peak season of adults of the overwintering generation was early to middle of May. The results of seasonal periodicity of BAW monitored by sex pheromone trap during 2009 and 2010 indicated that five generations were passed in Jeju. The peak season of 1st generation was on middle of April, 2nd generation on middle of July, 3rd generation on early of August, 4th generation on late of August and 5th generation on middle of September. There were similar patterns by different above sea levels except the season of overwintering generation adults occurrence (March to May).
        196.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        5,700원
        197.
        2011.06 구독 인증기관 무료, 개인회원 유료
        This study was conducted in order to evaluate the effect of sericin-calcium (SC) as therapy for ovariectomy-induced osteoporosis in rats. Three weeks after ovariectomy (OVX), Sprague-Dawley rats were divided randomly into three groups: sham-operated group (Sham), ovariectomized group, and SC-treatment group (OVX+SC). Rats in the OVX+SC group were given drinking water containing 0.07% SC for eight weeks. Bone breaking force, mineralization, and blood parameters related to bone metabolism were analyzed. In OVX animals, blood concentration of 17β-estradiol showed a significant decrease, while osteocalcin and type I collagen C-terminal telopeptides (CTx) showed an increase. Breaking force of femurs as well as bone mineral density (BMD), ash, calcium, and phosphorus in femurs showed a significant decrease following OVX. Treatment with SC (0.07% in drinking water) resulted not only in remarkable restoration of the decreased 17β-estradiol and increased osteocalcin and CTx concentrations, but also led to recovery of decreased femoral breaking force, BMD, ash, calcium, and phosphorus. It is suggested that SC effectively improves bone density by preventing bone turnover-mediated osteocalcin, CTx, and minerals, and that it could be a potential candidate for use in therapy or prevention of post-menopausal osteoporosis.
        4,200원
        198.
        2011.05 구독 인증기관·개인회원 무료
        Arrowhead scale, Unaspis yanonensis, is a serious scale insect pest of citrus in Jeju. The sticky taping of 1.0 cm diameter twig was a good survey method for arrowhead scale crawler. There are three times crawler occurrence season - late May to early July, late July to middle September and late September to late October. But the third occurred crawlers are all died during overwintering in open-field groves. This study was conducted to provide information on efficient sampling plan for arrowhead scale within the tree. Twig and fruit was fit for secondary sample unit by two-stage variance analysis. Both sample number per tree (primary sample unit) was eight twigs or fruits. Taylor’s power law was better described the distribution characteristic of arrowhead scale than Iwao’s patchiness regression. The slope of both linear regressions was greater than “1” which means aggregative distribution pattern. Minimum sample size to estimate the density was calculated using by two parameters of Taylor’s power law. To estimate the mean density on twig and fruit by binomial sampling plan, the optimum tally threshold was 5 and 7, respectively.