• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.396-403
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• 2014

Ginseng (Panax ginseng C. A. Meyer) is an economically valuable pharmaceutical crop in Korea. In order to find promising biocontrol agents for soil-borne fungal pathogens which infect ginseng roots, we have isolated actinomycete, BK185 from soil. The isolate was investigated for the antifungal activity against to ginseng rot pathogens prior to testing genetic and chemical properties. The strain was identified as Streptomyces sp. using phylogenetic analysis based on 16S rRNA gene sequence. The most closely related species was S. sporoclivatus and S. geldanamycininus with high similarities (>99%). The isolate, BK185 showed positive reaction for PCR detection targeting biosynthetic gene clusters of PKS (Type-I polyketide synthase) and NRPS (Non-ribosomal polypeptide synthetase) genes. Major metabolite from the BK185 was analyzed by The LC/MS and identified to geldamycin, which was known to contained broad antibacterial, antifungal or anticancer activities. The results provide evidences that the strain, BK185 can be promising biocontrol agent for ginseng organic farming.

• Journal of Life Science
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• v.28 no.8
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• pp.931-937
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• 2018

Triptolide is a compound found in Tripterygium wilfordii and reported to have an anti-inflammatory and anti-oxidant activities. A previous study shows that the dietary supplementation with triptolide increases resistance to environmental stressors, including oxidative stress, heat shock, and ultraviolet irradiation, and extends lifespan in C. elegans. Here, we investigated the underlying mechanisms involved in the lifespan-extending effect of triptolide. The effect of triptolide on age-related diseases, such as diabetes mellitus and Alzheimer's disease, was also examined using animal disease models. The longevity phenotype conferred by triptolide was not observed in the eat-2 mutant, a well-known genetic model of dietary restriction, while there was an additional lifespan extension with triptolide in age-1 and clk-1 mutants. The long lifespan of age-1 mutant is resulted from a reduced insulin/IGF-1-like signaling and the clk-1 mutant lives longer than wild-type due to dysfunction of mitochondrial electron transport chain reaction. The effect of dietary restriction using bacterial dilution on lifespan also overlapped with that of triptolide. The toxicity of high glucose diet or transgenic human amyloid beta gene was significantly suppressed by the supplementation with triptolide. These findings suggest that triptolide can mimic the effect of dietary restriction on lifespan and onset of age-related diseases. We conclude that triptolide can be a strong candidate for the development of dietary restriction mimetics.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.333-341
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• 2001

The actual overall migration data obtained from plastic food packaging materials into food simulants under high temperature testing conditions as described in the regulations of European Union, USA, and Korea or Japan were compared. Overall migration values(OMVs) with non-fatty food simulants under high temperature conditions were observed to be generally below 2.5 mg/dm$^2$ except polyamides(CPA and PA 6,6) which were tested at 121$^{\circ}C$ for 2 hrs. As for the fatty food simulants, the OMVs with soybean oil were higher than other simulants. Among the films tested, PVC wrap showed higher OMVs ranging between 23.9 and 54.6 mg/dm$^2$than others. The OMVs were measured at higher level with the elevation of contact temperature and the extension of contact time, and in fatty food simulants rather than in non-fatty simulants. Under similar testing temperature and time conditions. the OMVs tended to be increased in polar films like PA with polar simulants, and contrarily in non-polar films like PO with non-polar simulants. It is noteworthy that a discrepancy with regard to the result of OMVs was observed for some films as a result of different migration testing methods and conditions of each country areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.110-115
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• 1983

This study was to demonstrate the additional effect of fat-soluble vitamins on inhibitory action of Korean ginseng (Panax ginseng C. A. Meyer) saponin to lipoperoxide formation in vitro and in vivo. The ginseng saponin and vitamins were added to the substrate of linoleic acid and incubated on a shaking water-bath at $60^{\circ}C$, and the inhibitory action on lipoperoxide formation was examined by measuring the TBA value (532 nm), POV (500 nm) and EDA (electorn donating ability to ${\alpha}$, ${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl at 525nm) for in vitro. The ginseng saponin and vitamins were administered to Sprague-Dawley rats (♂, 100~120g) orally, and the inhibitory effect on lipoperoxide formation was examined by measuring the TBA value in vivo. EDA to DPPH of ginseng saponin added with vitamin A and D were higher than that of ginseng saponin only. Ginseng saponin added with vitamin A and D inhibited strongly lipoperoxide formation of initial step by extension of induction period in vitro. Fat-soluble vitamins such as vitamin E and A were approved the additional effect on inhibitory action of lipoperoxide formation in vitro. The additional effect of fat-soluble vitamins to ginseng saponin for inhibitory action of lipoperoxide formation was effective vitamin E and D for blood, vitamin A and E for liver in vivo.

• Ocean and Polar Research
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• v.26 no.4
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• pp.595-606
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• 2004

Hydrographic survey in the Korea Strait has long history that has begun in August 1917 at the Busan - Tsushima cross section, still continues to date. However, chemical properties of bottom cold water found exclusively in the western channel of the Korea Strait during summer did not receive much scientific attention. The aim of the study is to decipher the enigmatic origin of the Korea Strait Bottom Cold Water (KSBCW) in terms of chemical properties. The physicochemical properties of the KSBCW are extracted from the CREAHS II hydrographic data. OMP method was applied to analyze origin of the KSBCW quantitatively. The KSBCW is well defined by low temperature below $10^{\circ}C$. The cold waters exhibited the local presence near the coast at about 120m depth with a thickness of 20m to 30m. The cold water was characterized by relatively cold, saline and higher chemical concentrations than adjacent waters. The KSBCW seems to have different origin kom that of the coastal upwelled waters at the Ulgi-Gampo because it is saline, denser and contains considerably less dissolved oxygen than upwelled waters. The physicochemical properties are reported to have noticeable annual variations which suggest the complex origin of the KSBCW. OMP analysis show that the KSBCW is a mixture of three water types; TMW (24%), ESIW (36%) and ESPW (40%). Relationship between the KSBCW and the east Sea circulation is traced by mapping the water masses that have similar T, S and DO of KSBCW. The result showed that the KSBCW is most possibly an extension of southward flowing coastal intermediate waters. Front these results, we expect that the monitoring KSBCW will provide us valuable information about the East Sea circulation.

• The KIPS Transactions:PartC
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• v.18C no.3
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• pp.135-142
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• 2011

Recently, the strategy for N-screen service is in the spotlight along with the consumer's need to use contents regardless of time and place due to the rapid development of communication technology, which is meshing with the desire of service providers seeking a new business model. N-screen, as a screen-extension-concept service which enables consumers to continuously share and use contents in various equipments such as TV, computer and portable terminals, is an advanced type of 3-screen service strategy initially proposed by AT&T, an American telecommunication company. In the N-screen service for pay-contents, in order to support continuous screen changes to and from various equipments, temporary watching right should be given to the equipment intended for screen change. However, it is impossible to give the temporary watching right in the present broadcasting environment, adopting an access-control system. In this paper, the access-control technology being used for pay-contents in the present broadcasting environment and the reason for not being able to give temporary watching right, will be examined. After the examination, the solution for delegation of watching right by using an additional key on the basis of currently used access-control technology, will be proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2879-2887
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• 2011

This research is aimed for the better understanding of corrosion behavior of carbon steel in ETA or $NH_3$ solution at high temperature. To minimize the corrosion it is important to select proper pH control agent(s), which also let it maintain basic or reductive environment inside the steel pipe. This work will provide the practical guideline which can be applied to the nuclear power plant for developing the life extension method of carbon steel. Experiments were carried out by measuring the corrosion rate using the potentiodynamic polarization curve of carbon steel in ETA and NH3 at different temperatures. The corrosion rate was estimated by using the Tafel curve measured under various test conditions: i) $NH_3$ is less than ETA as a pH agent. ii) the corrosion was reduced at high pH, and iii) the corrosion was maximum in the temperature range of $150\sim200^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1365-1371
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• 2011

The intensity and duration of sexual behavior in Bos indicus was assessed through the continuous observation of sexual receptivity. Two groups of cows were formed: only synchronized (n = 50) and other group further superovulated (n = 20). An intravaginal implant that released progesterone over 9 d was used. After removing the implant, 25 mg of $PGF_{2{\alpha}}$ was administered. In the superovulated group, the administration of 280 mg (Follicle stimulant hormone) FSH-P1 per cow with a decreasing dosage over 4 d was utilized. In both groups, behavioral observations began at the moment of implant removal. Sexual behavior was analyzed using a Kruskal-Wallis test to compare the mean of hours in estrus, effective mountings and number of mounts/hour during estrus. A nonparametric survival analysis was performed using the time in two ways: i) when an event happened it was placed in a 24 h timeframe and, ii) the time of observation in continuous form (96 h) assessing the difference between curves by the log rank test Chi-square. The only significant difference was the number of mounts/h during receptivity (p<0.05). In the superovulated group three periods of sexual activity during the day were identified, with these events being of greater frequency and duration than the synchronized group (p = 0.02); besides, the superovulated group began estrus before the synchronized group (p = 0.0035) when using the total period. In a simulation study, when the number of observations went from two (06:00-18:00) to three periods (06:00, 12:00 and 18:00) cows detected accurately (<6 h after the onset) increased more than 20%. The results show that superovulated cows presented greater intensity and duration of sexual activity in contrast with only synchronized animals.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.328-334
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• 2022

BACKGROUND: The low temperature at flowering period break the balance between vegetative and reproductive growth of apple tree. Summer pruning has been used to control vegetative growth. So, this study was conducted to investigate the effect of summer pruning time on shoot growth and fruit quality of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period. METHODS AND RESULTS: The following treatments were applied to tree : a) control (no summer pruning), b) pruned 26 June, c) pruned 30 July, d) pruned 28 August, and e) pruned 26 September. The summer pruning significantly increased light penetration and fruit red color by reducing the total shoot growth compared with control. And the summer pruning control the outbreak of apple valsa canker. But the summer pruning at the end of June increased regrowth of shoot and pruning weight compared with the summer pruning at the end of August. The summer pruning at 30 July had the highest fruit weight, but return bloom was the highest in the summer pruning at 28 August. CONCLUSION(S): These results indicated the optimum summer pruning time of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period were the end of August.

• Education of Primary School Mathematics
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• v.15 no.1
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• pp.1-11
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• 2012

Unlike traditional cognitive theory, situated cognition theory has been understood as a pedagogical theory that highly reflects the constructivist nature of learning. In order to practice situated learning in school, situations in the classroom are very important in which real teaching and learning occurs. Due to the fact that learning is the process of mental activities which is considerably dependent on conditions and context, it focuses more on the learning process and real-situation experiences rather than the result itself. In mathematics education, teaching students the ability to solve given problems in a conventional way is not enough anymore. The purpose of this research is to suggest the direction of mathematical education in the classroom by analyzing the implications of situated cognition theory and situated learning for 'doing mathematics' in classroom teaching. In this research, we introduce briefly about situated cognition theory and situated learning, compare the phenomenon of mathematics in the classroom to that in the mathematician's mind, and finally propose the applications of situated cognition theory in the mathematics education based on three perspectives of situated cognition theory the embodiment thesis, the embedding thesis, and the extension thesis.