Adenostemma madurense DC. (Asteraceae, Adenostemma L.), which is known to be distributed in Japan, Taiwan, Thailand and Nepal was recently found on Jeju Island in Korea. It is morphologically allied to A. madurense but distinguished from A. lavenia (L.) Kuntze by having such characters as broadly ovate or ovate to oblong leaves, 15-21 ㎝ long × 7-12 ㎝ wide and smooth achenes with slightly muricate at the upper. Furthermore, A. madurense is found in dry mountain slopes in evergreen forests while Adenostemma lavenia occures in the wetland and side of pond. This taxon was named ‘San-mul-meo-wi’ in Korean based on its habitat. We provide a description, illustrations, photographs, and the key to the related species in Korea.

DC/DC switching power converters are commonly used to generate a regulated DC output voltage with high efficiency. The advanced DC/DC converter uses a PWM-IC with OP-Amp. (Operational Amplifier) to control a MOSFET (metal-oxide semiconductor field effect transistor), which is a switching component, efficiently. In this paper, it is shown that the electrical characteristics of OP-Amp. are affected by radiations of γ rays using 60Co for TID (Total Ionizing Dose) testing and 5 heavy ions for SEL (Single Event Latch-up) testing. TID testing on OP-Amp. is accomplished up to the total dose of 30 krad, and the cross section(㎠) versus LET(MeV/mg/㎠ ) in the OP-Amp. operation is evaluated SEL testing after implementation of the controller board.

Background: Mahonia Nepalensis DC. (Hoang lien o ro), the specie of the family Berberidaceae, is widely distributed in the high mountainous areas at altitudes 1700 – 1900 m of Vietnam. It is found that the stem of Mahonia nepalensis indicated anti-inflammatory, anti-bacterial and antifungal activities and they are used particularly for the treatment of eczema, psoriasis, and other skin conditions. However, no study on the antioxidant and anti-cancer activities of Mahonia Nepalensis stem has been previously reported. The aim of this study was to evaluate anti-oxidant and anti-cancer activities of Mahonia Nepalensis stem. Methods and Results: The stem pieces of Mahonia Nepalensis were dried and extracted three times with 100% methanol. After that, the extract was suspended in distilled water and then partitioned with n-hexane, ethyl-acetate (EtOAc) and butanol (water saturated BuOH) fractions were then evaporated using a vacuum rotary evaporator. Evaluation of the anti-oxidative activity of Mahonia Nepalensis was carried out using a DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-producing system. The results revealed that the ethyl acetate fraction of M. nepalensis possessed higher potential DPPH radical scavenging activity (IC50, 81.88 ± 1.33㎍/㎖) than other fractions as well as BHT (2,6-Di-tert-Butyl-4-methylphenol) (IC50, 250.49 ± 1.60㎍/㎖). The reducing power assay was also investigated and EtOAc fraction showed higher absorbance values than other fractions. At 1.0 mg/ml concentration, EtOAc fraction showed absorbance of 1.72, be higher than Ascorbic acid. Cell viability was evaluated according to the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl tetrazolium Bromide) assay. By MTT assay, all fractions showed a significant reduction in cell viability on COLO 205 (Human colon carcinoma cell) at the highest concentration tested (200㎍/ ㎖) with over 70% decrease in cell viability was obtained, and the highest significantly inhibiting effect occurred in butanol fraction with approximately 90% reduction in cell viability. Conclusion: We demonstrated that Mahonia Nepalensis stem extract has highly potential in anti-cancer activity. Further studies are necessary in order to explore the variety of Mahonia Nepalensis stem to be applied as a valuable natural material.

Plant breeding requires the collection of genetically diverse genetic resources. Studies on the characteristics of Platycodon grandiflorum resources have not been carried out so far. The present study was carried out to discriminate P. grandiflorum based on morphological characteristics and genetic diversity using simple sequence repeat (SSR) markers. Methods and Results :We collected 11 P. grandiflorum cultivars: Maries II, Hakone double white, Hakone double blue, Fuji white, Fuji pink, Fuji blue, Astra white, Astra pink, Astra blue, Astra semi-double blue and Jangbaek. Analyses of the morphological characteristics of the collection were conducted for aerial parts (flower, stem and leaf) and underground parts (root). Next, the genetic diversity of all P. grandiflorum resources was analyzed using SSR markers employing the DNA fragment analysis method. We determined that the 11 P. grandiflorum cultivars analyzed could be classified by plant length, leaf number and root characteristic. Based on the genetic diversity analysis, these cultivars were classified into four distinct groups. Conclusions : These findings could be used for further research on cultivar development using molecular breeding techniques and for conservation of the genetic diversity of P. grandiflorum. Moreover, the markers could be used for genetic mapping of the plant and marker-assisted selection for crop breeding.

Herein, we discuss the in situ measurement of the electron temperature in the ionosphere/plasmasphere by means of DC Langmuir probes. Major instruments which have been reported are a conventional DC Langmuir probe, whose probe voltage is swept; a pulsed probe, which uses pulsed bias voltage; a rectification probe, which uses sinusoidal signal; and a resonance cone probe, which uses radio wave propagation. The content reviews past observations made with the instruments above. We also discuss technical factors that should be taken into account for reliable measurement, such as problems related to the contamination of electrodes and the satellite surface. Finally, we discuss research topics to be studied in the near future.

The influence of seed maturity, stratification, and seed washing method on seed germination were investigated for establishment of seed propagation system in dropwort (Oenanthe stolonifera DC). Seed germination rate was increased as period of the seed ripening increased, especially the seed over 40 days after flowering showed the highest germination rate. The optimum period of cold stratification treatment to promote seed germination was about 8 weeks. The seed treated by a cold wet stratification with sand exhibited higher germination rate compared to the seed treated by a cold wet stratification without sand. The stratified seeds that were stored in the ground having fluctuating temperature were improved up to 19%, while stratification stored under constant temperature(4℃) did not improve germination rate. In addition, 8 weeks of stratification period under fluctuating temperature in the ground was most effective. Sodium hypochlorite, vital oxide, and distilled water were used as chemicals to remove the germination inhibitor of seed coat. Water washing of seed coat after soaking in 0.5% sodium hypochlorite and 0.0005% vital oxide for three minutes and 60 minutes respectively could effectively remove the germination inhibitors in the seed coat.

생강나무 줄기와 초피 과피의 60% ethanol과 열수 추출물의 식중독 균에 대한 항균 활성과 추출물의 열안정성에 대하여 알아보았다. 100 mg/mL의 농도에서 생강나무 줄기의 60% ethanol 추출물은 MRSA에 대하여 31.50 mm, 열수추출물은 S. aureus에 대해 25.5 mm의 생육 저해환을 보이며 가장 높은 항균활성을 보였으며, B. cereus에 대해서는 가장 낮은 항균활성을 보였다. 같은 농도에서 초피 과피의 60% ethanol 추출물의 항균효과는 S. aurues와 B. cereus에 대해 25 mm의 생육 저해환을 나타냈으며, 열수추출물은 S. aurues 에 대해 22 mm의 생육저해환을 나타내 항균 효과가 가장 크게 나타났으며, E. coli 에 대해서는 낮은 항균활성을 나타내었다. 생강나무 줄기와 초피 과피의 60% ethanol, 열수 추출물 모두 농도가 낮아짐에 따라 생육 저해환의 크기가 작아지는 현상을 보였으며, ethanol추출물이 열수 추출물에 비해 다소 높은 항균력을 나타냈다. 또 추출물의 열안정성 실험에서 열처리군과 비열처리군(대조구)을 비교했을 때 항균 효과가 감소하지 않는 것으로 보아 생강나무 줄기와 초피 과피 추출물은 열에 안정하다고 판단된다. 본 연구 결과 생강나무 줄기와 초피 과피 추출물에 미생물 부패 방지에 효과적인 항균 물질이 함유되어 있으며 비교적 열에 안정하므로 천연보존료로서 산업적 응용이 가능할 것이라 사료된다.

흑마늘 음료의 기호성과 기능성 증진을 위해 흑마늘과 미나리의 배합비를 각각 3:0(BD-1), 2:1(BD-2), 1:1(BD-3), 1:2(BD-4)의 비율(w/w)로 달리하여 제조한 음료의 식품학적 특성과 항산화 활성을 비교 검토 하였다. 흑마늘 미나리 혼합음료의 pH는 미나리 첨가량이 증가함에 따라 증가하였으나, 당도는 감소하는 경향을 나타내었다. 색도는 L값과 b값은 유의적인 차이를 보이지 않았으나, a값은 미나리 첨가량이 증가함에 따라 2.40(BD-1)에서 6.46(BD-4)로 증가 하였다. 폴리페놀 함량은 BD-4에서 46.96 μg/mL으로 가장 높게 나타났으며, BD-3(42.36 μg/mL), BD-2(41.91 μg/mL), BD-1(28.48 μg/mL) 순으로 나타났다. SOD 유사활성은 BD-4에서 18.60%으로 가장 높은 활성을 나타내었으며, BD-3(15.53%), BD-2(12.53%), BD-1(10.27%) 순으로 활성을 나타내었다. ABTS 라디칼 소거능은 BD-1에서 28.72%로 가장 낮게 측정되었으며, 미나리 첨가 비율이 증가함에 따라 유의적으로 증가하여 BD-2는 39.43%, BD-3은 45.69%, BD-4는 52.51%로 나타났다. 철 이온 킬레이트 효과는 미나리 첨가량이 증가함에 따라 증가하였으며, BD-1(6.38%)에 비해 BD-4(39.94%)에서 6배 높게 측정되었다. 수용성 비타민(B1, B2, B6, C) 함량은 미나리 첨가량이 증가함에 따라 증가하는 경향을 나타내었으며, 특히 비타민 C의 경우 BD-1(130.10 μg/mL)에 비해 BD-4(806.21 μg/mL)가 6배 가량 증가하였다. 관능검사의 경우도 색, 향, 맛, 종합적 기호도에서 BD-4가 가장 양호하였다. 이러한 결과를 종합해 보면, 흑마늘 미나리 혼합 음료를 제조할 경우 흑마늘과 미나리를 1:2 비율(w/w)로 혼합하는 것이 생리활성과 관능적 품질 특성 측면에서 우수할 것으로 사료된다.

In this study, AC/DC responses of CNT-filled cement composites are measured and compared. Based on the results, it is found that AC measurement method is more reliable to measure the electrical resistance of CNT-filled cement composites.

Ginseng (Panax ginseng) is frequently used in Asian countries as a traditional medicine. The major components of ginseng are ginsenosides. Among these, ginsenoside compound K has been reported to prevent the formation of malignancy and metastasis of cancer by blocking the formation of tumor and suppressing the invasion of cancer cells. In this study, ginsenoside Rb1 was converted into compound K, via secreted β-glucosidase enzyme from the Leuconostoc lactis DC201 isolated, which was extracted from Kimchi. The strain DC201 was suspended and cultured in MRS broth at 37℃. Subsequently, the residue from the cultured broth supernatant was precipitated with EtOH and then dissolved in 20 mM sodium phosphate buffer (pH 6.0) to obtain an enzyme liquid. Meanwhile, the crude enzyme solution was mixed with ginsenoside Rb1 at a ratio of 1:4 (v/v).The reaction was carried out at 30℃ and 190 rpm for 72 hours, and then analyzed by TLC and HPLC. The result showed that ginsenoside Rb1 was transformed into compound K after 72 hours post reaction.

본 논문은 공진형 인버터로 구성된 X-ray 고전압 발생기와 고주파 고전압 변압기의 운영 시스템을 제안하였다. X 선 발생장치는 무소음화와 소형화하였으며, 50[㎑]이상의 구동 주파수로 동작하게 하였고, 일반전원을 사용할 때 발생 한 전력으로 인한 노이즈, 조사조건의 저하문제 등의 문제점을 해소하였다. 또한, X선관 전압 제어기와 관전류 제어기 및 고주파 고전압 변압기의 필라멘트 가열용 변압기를 고주파용으로 설 계, 제작함으로써 X선 장치의 효율적 운영이 되도록 하였다.

본 논문은 벅, 부스터, 벅-부스트 등의 부이용 DC-DC 컨버터 성능에 대하여 기술하였다. PV 시스템과 연계한 컨버터에 관한 특성이 고려된 동작특성 및 충전효율에 대하여 분석하였다. 그것은 MPPT 알고리즘과 더불어 수행되었다. 컨버터를 위한 기본 스위칭 방정식을 기술하고, 스위칭 상태에 따른 방정식을 해석하였다. 이 해석은 부이선택에 초점을 맞추고 있으며, 또한 컨버터 동작 및 제안한 알고리즘의 성능을 관찰하였다. 마지막으로 부이에 적합한 DC-DC 컨버터를 제안하였으며, 벅 컨버터에 대한 특성실험도 수행하였다.