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        검색결과 583

        221.
        2013.06 구독 인증기관 무료, 개인회원 유료
        The current study was conducted in order to investigate bone formation using matrigel and angiogenic factors with HA and poly ε-caprolactone (HA/PCL) in a rat calvarial defect model. Calvarial defect formation was surgically created in Sprague Dawley rats (n=36). Rats in the control group (CD group, n=6) did not receive a graft. The HA/ PCL scaffold was grafted with matrigel (M-HA/PCL group, n=6) or without matrigel (HA/PCL group, n=6); and 100 ng of vascular endothelial growth factor with HA/ PCL scaffold containing matrigel (VEGF100 group, n=6), 100 ng (PDGF100 group, n=6) and 300 ng (PDGF300 group, n=6) of PDGF with HA/PCL scaffold containing matrigel were grafted in calvarial defects, respectively. Four weeks after surgery, bone formation was evaluated with micro computed tomography (micro CT) scanning, and histologically. According to the results, bone mineral density was significantly increased in the VEGF100, PDGF100, and PDGF300 groups compared to the HA/PCL group, in which angiogenic factors were not applied. In histological evaluation, more new bone formation around scaffolds was observed in the PDGF100 and the PDGF300 groups, compared with the VEGF100 group. Thus, the results indicate that HA/PCL containing matrigel with VEGF and PDGF is an effective grafting material for enhancement of bone formation in critical-sized bone defects. Especially, due to its price and capacity for bone formation, PDGF may be more effective than VEGF.
        4,000원
        222.
        2013.06 구독 인증기관 무료, 개인회원 유료
        This study was undertaken to determine free radical scavenging capacity and oxidative DNA damage protecting activity of methanol extract of red tea stem. The extract was subjected to assess their antioxidant potential using various in vitro systems such as DPPH•, ABTS•+ , super oxide and nitric oxide free radicals and it exhibited IC50 values of 68.88 ± 1.1, 12.08 ± 0.65, 404.38 ± 1.6, 93.6 ± 2.7, µg/mL respectively. Red tea extract also showed ferric reducing ability (FRAP) with 2606.85 mmol Fe (II)/g of extract. Furthermore, Methanol extract of red tea stem showed significant DNA damage protecting activity in concentration dependent manner against H2O2+UV induced photolysis on pUC19 plasmid DNA. Results of this study showed that the methanol extract of Red Tea stem has strong antioxidant potential along oxidative DNA damage protecting capacity that would be the significant sources of natural antioxidants, which might be helpful in preventing the progress of various oxidative stress generated diseases. Further study is necessary for isolation and characterization of the active antioxidants, which may serve as a potential source of natural antioxidant.
        4,000원
        223.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The recent development in genetic assisted selection (combining traditional- and genome assisted selection method) and reproduction technologies will allow multiplying elite cow in Hanwoo small farm. This review describes the new context and corresponding needs for genome assisted selection schemes and how reproductive technologies can be incorporated to get more genetic gain for cow genetic improvement in Hanwoo. New improved massive phenotypes and pedigree information are being generated from commercial farm sector and these are allowing to do genetic evaluation using BLUP to get elite cows in Korea. Moreover cattle genome information can now be incorporated into breeding program. In this context, this review will discuss about combining the reproductive techniques (Multiple Ovulation Embryo Transfer; MOET) and genome assisted selection method to get more genetic gain in Hanwoo breeding program. Finally, how these technologies can be used for multiplication of elite cow in small farm was discussed.
        4,000원
        224.
        2013.06 구독 인증기관 무료, 개인회원 유료
        Uncovering enzyme (UCE), encoded by the human NAGPA, is a trans-Golgi enzyme that adds the mannose-6- phosphate recognition tag on lysosomal enzymes destined for the lysosome. Mutations in NAGPA are known to cause stuttering, a common speech disorder with unknown etiology. The human NAGPA gene is transcribed into two different forms, probably due to alternative splicing. One of them, known as a brain isoform, is lacking exon 8 (102-bp). We performed quantitative real-time PCR for the NAGPA brain and non-brain isoforms in a cDNA panel originating from 16 human tissues and 24 sub-brain regions. According to our findings, the relative quantity of the NAGPA brain isoform in the brain was 4.7 times more than that in the control cDNA, a pooled mixture of equal amounts of cDNAs from the 16 different tissues. Further analysis using the cDNA panel originating from 24 different sub-brain regions revealed that the cerebral cortex contained the largest amount of NAGPA brain isoform. Relative quantity in the cerebral cortex was 8.6 times more than that in the control cDNA (P=0.00004). The lowest quantity of this isoform was detected in cDNA from the pituitary gland. In conclusion, findings of the current study suggest that the cerebral cortex, expressing the highest quantity of the NAGPA brain isoform, might be the region associated with speech function.
        4,000원
        225.
        2013.05 구독 인증기관 무료, 개인회원 유료
        Smart phones have drastically changed the life of today’s competitive world. Smart phone application (App) developers are trying their best to meet the customer requirements in the most efficient way while considering all its attributes. However smart phone service quality has been given less consideration comparatively during the last few years. This paper proposes a measurement method for improving service quality of smart phone application. This method combines the service quality performance model and process capability index. The service quality performance model is used to identify service items that require improvement. Process capability index is used to prioritize these items for improvement. We collected data on satisfaction level of customers who have used application service. By the proposed method, we found five significant service items from three categories - execution, security and resilience and prioritized those items for improvement.
        4,000원
        226.
        2013.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Microtubule-associated protein 1B (MAP1B), a member of MAP1 family, plays a key role in neuronal development. MAP1B binds to many kinds of proteins directly or indirectly. This study was performed to investigate whether MAP1B interacts with GAPDH in bovine follicles using immunoprecipitation (IP) with Western blot analysis and immunohistochemisty. The mRNA expressions of MAP1B and glyceraldehydes 3-phosphate dehydrogenase (GAPDH) were down-regulated in bovine follicular cystic follicles (FCF). In parallel with the mRNA levels, their protein levels were also down-regulated in FCFs. In addition, MAP1B and GAPDH were co-localized at the cytoplasm of follicles. IP with Western blot analysis showed that MAP1B bound to GAPDH in normal follicles, but their binding was absent in FCFs, suggesting a low level of MAP1B and/or GAPDH expressions in FCFs. Taken together, these results suggest that MAP1B interacted with GAPDH may play a role in bovine follicle development, and that GAPDH does not function always as a loading control in bovine follicles.
        4,000원
        227.
        2013.03 구독 인증기관 무료, 개인회원 유료
        The objective of this experiment was to assess the relationship between electrical resistance of the vaginal mucosa and plasma progesterone for optimal mating time in the bitch. Eight mature beagle bitches were examined, and we observed eight times of estrus. Vaginal electric resistance was recorded weekly using a Draminski ovulation detector in anestrus, and daily in estrus. Plasma progesterone concentration was estimated by radioimmunoassay. In the bitch, incline in vaginal electric resistance (376.20 ± 105.63 units) showed a closely association with the onset of proestrus. Ovulation day was determined as the first day when plasma progesterone concentration increased above 5.0 ng/ml (Day 0). On Day 0, vaginal mucous electric resistance was 438 ± 132 units. Vaginal mucous electric resistance showed a slight decrease or was maintained until Day 0. However, it showed an explosive increase, and peaked on Day 1~3, which was above 600 units. Two of eight cases peaked on Day 1, three of eight cases were revealed on Day 2, and others were revealed on Day 3. After Day 4, resistance showed a rapid drop to below 600 units and reached 200 units on Day 8. The optimal mating time was determined when vaginal mucous electric resistance was above 600 units.
        4,000원
        228.
        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
        229.
        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
        230.
        2012.06 구독 인증기관 무료, 개인회원 유료
        We developed the “Nest Finder System” to detect the breeding ecology of cavity nesters. Nest Finder System is composed of three parts, camera, transfer and recorder parts. In camera part, we utilized three types like pin camera, CCTV camera and endoscope with CMOS lens. Electricity and information was transferred with cable lines, and the information were directly recorded into sony digital recorder (GV-HD 700) or hard disk. To survey the breeding status of cavity nester, we disassembled the cone lens (TVC-MN4428C) applicable to enter the natural tree hole ranging no less than 30 mm. To support the camera and transfer part reaching at the hole located about 15m height, we used a couples of carbon poles in size of 1.8m, and its slender ending part was designed to fit each other. Nest Finder System can be applied to monitor breeding status of forest wildlife including cavity nesters, canopy nesters and aquatics. We discussed the potential problem in applying the equipment and analyzing the obtained data. Nest Finder System enable us to monitor the inner part of nest located at the upper part of trees not only coniferous and deciduous forests, and it can be applied to monitor the breeding ecology of aquatic organism.
        4,000원
        231.
        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.
        232.
        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.
        233.
        2012.05 구독 인증기관·개인회원 무료
        Papilio xuthus is known as the Asian swallowtail, Chinese yellow swallowtail, or as the Xuthus swallowtail. It overwinters in pupae stage. The study was conducted to investigate the temperature effect on adult emergence of overwintering P. xuthus pupae at four different constant temperatures (15, 20, 25 and 30°C) with photoperiod 10:14(L:D). The lower developmental thresholds of female, male and both sexes combined were 9.71, 11.03, and 10.49°C, respectively. Developmental period of overwintering pupae to adults decreased with increasing temperature between 15 and 30°C. Degree-days for adult emergence to female, male and both sexes combined were 227.27, 175.44, and 200.80DD, respectively. The relationship between the developmental rate and temperature was fitted by linear and five nonlinear developmental rate models (Logan 6, Lactin 1, 2 and Briere 1, 2). The variation of overwintering pupae development was described by the two-parameter Weibull distribution model. The adult emergence of overwintering P. xuthus pupae in spring can be explained and predicted by using developmental rate models and developmental distribution model. The effect of climate change on phenology and distribution of P. xuthus may be presented by the model.
        234.
        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
        235.
        2012.05 구독 인증기관·개인회원 무료
        Stick insect has several peculiarities like parthenogenesis, unique external features and dropping oviposition, so it is very hopeful to use for industrial insect. The oviposition was established by only female without fertilization with sperm of male which was not discovered during this study. The oviposition period was 37.3±14.9 days and the number of eggs per female was 41.5±16.5 eggs. The hatchability was 73.3% at 25℃and 66.7% after low temperature treatment(8℃, 60 days). The developmental periods and the length of egg were 100.9±4.2 days and 0.33±0.0cm, respectively, and the adult's life span was 49.7±16.0days. Differently other research which reported five nymph stage, the developmental stages of nymph showed five(62.9%) or six(37.1%) stages. The duration and the length of nymph increased according to the increase of nymph stage. Stick insect preferred the leaf of American locust, White oak, Chestnut, Bush clover in order but could be reared with food of the leaf of all these trees. Stick insects are herbivorus but made an attack each other when encountered in the small space. For sustaining mass rearing of stick insect, it is needed that the development of artificial diet and high density rearing method.
        236.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphene is an attractive material for device applications, but device characteristics are very unstable because the graphene is very sensitive to environmental factors such as charges nearby the graphene, metal contacts, defects, contaminants and other adsorbates. Since the interactions between graphene and environmental factors affect the electrical characteristics of graphene devices, the interpretation of electrical characteristics as simple as current-voltage curves is non-trivial, despite the common practice of using well known electrical characterization methods that have been used in silicon MOSFET. This paper addresses major obstacles in the electrical characterization of graphene devices and offers countermeasures to improve the accuracy of electrical characterization methods.
        4,000원
        237.
        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
        238.
        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.
        239.
        2011.10 구독 인증기관·개인회원 무료
        Sperm examination is an important tool in estimating the fertilizing capacity of an ejaculate. The number of spermatozoa in a semen dose, morphology and motility are important for the fertilization process. By evaluation of semen, artificial insemination (AI) using high quality of semen can increase fertilization rate. Boar semen is subject to contamination by various pathogens that can result in fertility disorders in sows. Among these pathogens, porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus (PPV), porcine circovirus-2 (PCV-2) are of particular importance and accurate monitoring prior to and during the presence of boars in AI stations is essential. Because of the high risk of dissemination of disease via AI, The absolute goal is to provide pathogen-free semen and this is feasible with the adequate measures. The disease affects boars semen causes a significant reduction quality. In this study we investigated the characterization boar semen in Jeju, interaction of pathogenic virus infection with characterization of boar semen. Forty-two boar semen from 13 farms were investigated. The semen were stored during 5 days at 17℃ and the sperm qualities in the stored semen were analysed. Visual-motility assessment is a tool (Computer- Assisted Semen Analysis) used to determine the quality of boar semen. Percentage of morphologically normal spermatozoa were assessed. PRRS ,PPV and PCV-2 were detected in boar semen using PCR. The motion characteristics in boar semen was showed 68.4±9.1% for motility, 48.6±7.1 μm/s for VAP, 45.3±7.0 μm/s for VSL, 79.1±8.7 μm/s for VCL, 1.3±0.2 μm/s for ALH, 8.3±0.4 Hz for BCF, 93.6±3.5% for STR, 57.9±6.4 % for LIN. The percentage of sperm with abnormal head, midepeice and tail were 0.3±0.7%, 14.4±12.5%, 4.9±6.6%, respectively. Based on the PCR method, PPV was detected in 20 samples (48%). However, PCV-2 and PRRSV were not detected in any cases. Marked differences in motility and morphology between PPV negative and PPV positive semen were not observed. Sperm cell production was not affected by PPV infection. However, slight increases in detached head, coiled tail after infection were observed (p<0.05). The motility of semen in Jeju is similar to case comparing with other regions in Korea. Although PPV in semen was not affected in semen quality, there is the high risk of virus excretion in the semen of Jeju boars. Therefore continuous screening tests for some particular pathogens in boar semen would be warranted.
        240.
        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.