• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.139-143
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• 2004

The twin-scale segments of nerine (Nerine bowdenii) were cultured to investigate the influence of NAA, BA and sucrose concentrations on in vitro bulblet formation. The formation of bulblets from twin-scale segments showed a good response both the percentage of bulblet formation and the number of bulblets per explant on MS medium supplemented with 1mg/L NAA and 2 mg/L BA. Formation of bulblet showed the highest efficiency on medium containing 30g/L, and the formation of bulblets was strongly inhibited on medium containing over 90g/L. When the twin-scale segments formed bulblets were subcultured three times to the same medium by 60 day subculture interval, the number of bulblets per explant was 6.5, 7.3 and 8.2 in order of first, second and third. The bulblets over 3mm in diameter were hypertrophied and rooted after transferring to the hormone-free MS medium. The plantlets over 50mm in height were successfully acclimatized in the soil mixed with the same volume of vermiculite and perlite, and the survival rate was over 95％.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.15-19
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• 1985

This study was carried out to develope the equations for estimating the areas of leaflet, leaf, and total leaf for 1, 2, 3, 4, 5, and 6 years old ginseng, Panax ginseng, grown in field. The highest correlation coefficient was found between leaflet area and product of leaflet length and width(LW) in all leaflets although leaflet shape varied somewhat according to the position and plant age. It was possible to estimate area of the leaf, and total leaf by one central leaflet in a compound leaf. The equations for estimating the leafet, leaf areas of 1 year differ to those of over 2 years old plant, but there was no difference among those of 2, 3, 4, 5, and 6 years. The equations for 1 year old are A =0.64 LW, A' =A/0.38, and for 2, 3, 4, 5, and 6 years old, A =0.60 LW, A' =A/0.32, A" =A' x number of leaves of central leaflet(A), leaf(A') and total leaf areas(A"), respectively. The estimation of leaflet, leaf, total leaf areas of ginseng plant grown under 20% light-transmittance rate was possible by using the equations mentioned.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.117-121
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• 1998

In the study to reduce the error on the method of sampling pine needles to monitor the atmospheric concentration of polychlorinated biphenyls(PBCs),it was found that: 1. Concentration of PCBs almost linearly increased from new to three-years-old pine needles, so that the biomonitoring method using pine needles canbe applied to measuring long-term contamination from air in a local area. Needles of differernt age should not be mixed in sampling but be seperately analysed .It no good idea comparing PCB concentrations of differently aged needles. 2. Concentratio n of PCBs on pine needles had nothing to do whit the indivisual and age of the pine tree. 3. Concentration of PCBs on pine needles growing avobe was lower than that on needke below. 4. Concentration of PCBs on pine needles locatied in poorly ventilative places such as needle of a forest was lower than that on needles in well-ventilated areas.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.623-627
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• 2014

Curcuma alismatifolia is becoming popular for cut flowers and potted plants due to its long inflorescence with many showy pink flowers. It is propagated by rhizomes and inflorescences that are similar to those of lotus. However, initiation of inflorescence development of each bract and flower has not been investigated. Therefore, this experiment was conducted to study the inflorescence development of Curcuma alismatifolia 'Chiangmai Pink' by scanning electron microscopy (SEM). When new shoots grew to 15-20 cm in a greenhouse at $25^{\circ}C$, the first bract initiated with a dome-shaped inflorescence apex, followed by initiation of additional bracts, forming the shape of the flower head. Florets were subtended by the first bract when five to seven bracts were formed. Four to six florets were subtended by each bract. The floret positioned in the center initiated and progressed upward first. When the center florets in the upper bracts were formed, florets next to the center floret subtended by the first bract were formed, and formation of the axillary florets progressed upward in sequential order.

• Fire Science and Engineering
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• v.24 no.3
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• pp.86-92
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• 2010

One of the limitation of wood as building materials is its flammability. The purpose of this paper is to examine the combustion properties of the Pinus rigida and Castanea savita which are grown in Korea and meet the desirable characteristics for use of construction materials. The cone calorimeter (ISO 5660-1) was used to determine the heat release rate (HRR) and fire smoke index, as well as CO and $CO_2$ production and smoke obscuration. The $HRR_{mean}$ of the Castanea savita and Pinus rigida at $50\;kW/m^2$ of radiant heat flux was $70.4\;kW/m^2$ and $68.5\;kW/m^2$. Furthermore, the THR of Castanea sativata was 120.8 MJ/kg and it was higher than the THR of Pinus rigida ($81.9\;MJ/m^$). These results are depend on the bulk density of tested wood species. The Castanea savita has high $CO_{mean}$ yield and high CO/$CO_2$ yield compared with that of Pinus rigida.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.6
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• pp.566-573
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• 2002

In this paper, dielectric characteristics of pathological tissues cultivated using the xenograft method were analyzed. Since cancerous tissues were extracted from the nude mouse just before the measurements, they were maintained as fresh as living tissues in the measurements. This would be one of the advantages to get more accurate and reliable results. Dielectric properties of four cancerous tissues such as brain cancer, breast cancer, colon cancer and gastric carcinoma were measured in the frequency range between 45 MHz and 5 GHz. For the measurement of the dielectric properties, 58 xenografted samples were used. It was found that all of the cancerous tissues had the similar dielectric constant values. Comparing with the normal tissues, dielectric constant values of brain cancer, breast cancer and colon cancer were higher than those of the normal tissues except gastric carcinoma in the frequency range.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.365-370
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• 2016

We collected leaves of Pinus koraiensis and Thuja koraiensis and roots of Bletilla striata from various sites in Korea. The leaf and root samples were surface-sterilized and endophytic fungi were isolated. Fungal isolates were identified based on their morphological characteristics and a phylogenetic analysis of internal transcribed spacer regions, large subunit regions, and the ${\beta}$-tubulin gene. Consequently, we identified five species of endophytic fungi, namely Colletotrichum simmondsii, Fusarium sterilihyphosum, Diatrypella pulvinata, Ochroconis globalis, and Sphaeria chrysosperma. These species have not been previously reported in Korea and we report them here with descriptions and illustrations.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.573-579
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• 2006

This experiment was conducted to investigate growth and flowering characteristics of Celosia argentea native to Korea treated by pinching and growth retardants, diniconazole, hexaconazole and daminozide. The more increased from one to three times of pinching, the more decreased in plant height and internode length but increased number of spadix and lateral branch. Spray application of diniconazole $50mg{\cdot}L^{-1}$ and daminozide $6,800mg{\cdot}L^{-1}$ decreased plant height, internode length and leaflength, but increased number of spadix, number of leaves and number of lateral branch.

• Journal of Life Science
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• v.18 no.3
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• pp.418-421
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• 2008

Membranes prepared from Bacillus cereus KCTC 3674, grown aerobically on a complex medium, oxidized NADH exclusively, whereas deamino-NADH was little oxidized. The respiratory chain-linked NADH oxidase system exhibited an apparent $K_m$ value of approximately 65 ${\mu}M$ for NADH. On the other hand, the enzymatic properties of the NADH: menadione oxidoreductase of NADH oxidase system were examined. The maximum activity of NADH: menadione oxidoreductase was obtained at pH 9.5 in the presence of 0.1 M KCl (or NaCl). The NADH: menadione oxidoreductase activity was very resistant to the respiratory chain inhibitors such as rotenone, capsaicin, and $AgNO_3$. Interestingly, the activity was stimulated by the 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO).

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.2
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• pp.85-89
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• 2006

To research of the improved mechanical properties of materials for spectacle lens cutting, SiC and TiC were used as the main powder. Also, $Al_2O_3$ and $Y_2O_3$ was included as a sintering additive. The weight ratio of the alumina($Al_2O_3$) to yttria($Y_2O_3$) was set to 1:1. The materials for spectacle lens cutting were fabricated by hot-pressing at $1810^{\circ}C$ for 1h and subsequently annealed at $1860^{\circ}C$ for 3, 6 and 12h to initiated grain growth. The longer annealing time is, the bigger the grain size is. The microstructures were observed by scanning electron microscopy (SEM). The SEM images were quantitatively analyzed by image analysis (Image-Pro Plus, Media Cybernetics, Maryland, U.S.A.). Crack deflection by elongated SiC grains was most frequently observed as the dominant toughening mechanism. Crack deflection was generally observed for elongated SiC grains with aspect ratio(AR) > 2.5 and grain thickness < $2.3{\mu}m$. Crack bridging was also observed as one of the operating toughness mechanism.