This study was aimed to isolate bacterial inoculants producing chitinase and evaluate their application effects on corn silage. Four corn silages were collected from four beef cattle farms to serve as the sources of bacterial inoculants. All isolates were tested against Fusarium graminearum head blight fungus MHGNU F132 to confirm their antifungal effects. The enzyme activities (carboxylesterase and chitinase) were also measured to isolate the bacterial inoculant. Based on the activities of anti-head blight fungus, carboxylesterase, and chitinase, L. buchneri L11-1 and L. paracasei L9-3 were subjected to silage production. Corn forage (cv. Gwangpyeongok) was ensiled into a 10 L mini silo (5 kg) in quadruplication for 90 days. A 2 × 2 factorial design consists of F. graminearum contamination at 1.0104 cfu/g (UCT (no contamination) vs. CT (contamination)) and inoculant application at 2.1 × 105 cfu/g (CON (no inoculant) vs. INO (inoculant)) used in this study. After 90 days of ensiling, the contents of CP, NDF, and ADF increased (p<0.05) by F. graminearum contamination, while IVDMD, acetate, and aerobic stability decreased (p<0.05). Meanwhile, aerobic stability decreased (p<0.05) by inoculant application. There were interaction effects (p<0.05) on IVNDFD, NH3-N, LAB, and yeast, which were highest in UCT-INO, UCT-CON, CT-INO, and CT-CON & INO, respectively. In conclusion, this study found that mold contamination could negatively impact silage quality, but isolated inoculants had limited effects on IVNDFD and yeast.

After Fukushima nuclear power plant accident in 2011, Concerns about accident of spent fuel pool increase. In Korea, the time of saturation of spent fuel pool is coming, but regulatory measures and safety evaluation are insufficient when occurring spent fuel pool accident. Thus, it is necessary to review of spent fuel pool accident in foreign countries to establish regulatory measures and safety evaluation of spent fuel pool accident suitable for domestic spent fuel pool. Therefore, we reviewed spent fuel pool accident that occurred at Fukushima Unit 4, SONGS Unit 2 and PAKS. In Japan, spent fuel pool accident occurred at Fukushima NPP in 2011. Tsunami was cause of the accident. Station Black Out occurred at Fukushima NPP and Emergency Diesel Generator lost their functions due to Tsunami. As a result, Loss of cooling happened in spent fuel pool at Fukushima NPP. For Unit 4, wall of spent fuel pool in Unit 4 was damaged due to hydrogen explosive, so loss of coolant in spent fuel pool of Unit 4 occurred. After the accident, the temperature of spent fuel pool increases to 75°C, but there was no damage to the spent fuel. In USA, spent fuel pool accident occurred at SONGS Unit 2 in 2013. The debris of nearby ocean is cause of the accident. The debris entered the system through a damaged Salt Water Cooling pump suction strainer. The debris obstructed flow through the Component Cooling Water heat exchanger and operation of Salt Water Cooling. The maximum spent fuel pool temperature during this event was 25.6°C. It was a value that satisfied the technical specifications of the SONGS NPP. In Ukraine, spent fuel pool accident occurred at PAKS in 2003. Unintentionally opened valve of cleaning tank is cause of the accident. Loss of coolant occurred in spent fuel pool of PAKS. Due to loss of coolant, spent fuels were exposed to the vapor state atmosphere, and oxidation occurred in the cladding tube of the spent fuel that rose to 1,400°C. In this study, Review of spent fuel pool accident in major foreign countries was conducted as basic studies for establishing regulatory measures and safety evaluation of spent fuel pool in Korea. Causes of each accident were different by structure of spent fuel pools. Result of this study will be contributed to establish safety measures of spent fuel pool accident suitable for domestic spent fuel pool facility.

Entomopathogenic fungi infect some arthropod pest and have been used for biological control. Some entomopathogenic fungi have high potential in insect pest management worldwide, and most of researches were given to Hypocreales order of Ascomycota, but little in Zygomycota, such as Entomophthorales in our country. We have identified some species belonging to Entomophthorales and investigated cultural features and ecology of Entomophaga aulicae. E. aulicae in sweet potato fields, where Aedia leucomelas was a dominant pest, had caused epizootics from 2002–2005. E. aulicae-infected A. leucomelas larva were mostly found from August to October and its occurrence was significantly related to the precipitation. E. aulicae were mainly observed in dead A. leucomelas larval populations (infection rate = 41.3% in 2002), rather than other lepidopteran pests. E. aulicae was morphologically and genetically identified and its virulence was characterized in laboratory conditions. Additionally, pest infection by Zoophthora radicans, Neozygites floridana and some Entomophthorales have been identified. On the basis with this information, we need research to predict the prevalence and to develop biological control agent using Entomophthorales including E. aulicae that contribute to regulation of host populations.

Human embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo. Human ES cells have the capacity to differentiate into various types of cells in the body. Human ES cells are indefinite source of cells for cell therapy in various degenerative disorders including neuronal disorders. Directed differentiation of human ES cells is a prerequisite for their clinical application. The objective of this study is to develop the culture condition for the derivation of neural precursor cells from human ES cells. Neural precursor cells were derived from human ES cells in a stepwise culture condition. Neural precursor cells in the form of neural rosette structures developed into neurospheres when cultured in suspension. Suspension culture of neurospheres has been maintained over 4 months. Expressions of nestin, soxl, sox2, pax3 and pax6 transcripts were upregulated during differentiation into neural precursor cells by RT-PCR analysis. In contrast, expression of oct4 was dramatically downregulated in neural precursor cells. Immunocytochemical analyses of neural precursor cells demonstrated expression of nestin and SOX1. When induced to differentiate on an adhesive substrate, neuro-spheres were able to differentiate into three lineages of neural systems, including neurons, astrocytes and oligo-dendrocytes. Transcripts of sox1 and pax6 were downregulated during differentiation of neural precursor cells into neurons. In contrast, expression of map2ab was elevated in the differentiated cells, relative to those in neural precursor cells. Neurons derived from neural precursor cells expressed NCAM, Tuj1, MAP2ab, NeuN and NF200 in immunocytochemical analyses. Presence of astrocytes was confirmed by expression of GFAP immuno-cytochemically. Oligodendrocytes were also observed by positive immuno-reactivities against oligodendrocyte marker O1. Results of this study demonstrate that a stepwise culture condition is developed for the derivation of neural precursor cells from human ES cells.

본 연구에서는 참마와 명아주의 항산화 및 항염증 효능을 평가하기 위해 참마와 명아주 에탄올 추출물을 이용하여 free radical 소거활성, enzyme-linked immunosorbent assay (ELISA) 실험을 수행하였다. 참마와 명아주 추출물의 free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) 소거활성(EC50)에서 각각 2.386, 0.524 mg/mL로 측정되었다. 또한 참마와 명아주 추출물의 혼합 시료의 free radical 소거활성은 참마 추출물 : 명아주 추출물 비율이 2 : 1일 때 가장 뛰어난 것으로 나타났다. IL-6와 TNF-α의 ELISA 실험을 통해 항염증 효능을 평가한 결과, 마우스 비장세포에서 IL-6의 경우 1 mg/mL 농도에서 참마 추출물은 대조군과 대비하여 27.17% IL-6 생성을 감소시켰으며, 명아주 추출물은 72.30%의 감소를 나타내었다. TNF-α의 경우 참마 추 출물은 61.97%, 명아주 추출물은 77.85%로 유의성 있는 TNF-α생성 감소 효능을 나타내었다. 이 결과들을 통하여 참마와 명아주 추출물은 항산화, 항염증 효능을 가지고 있으며, 이를 활용하여 항염증에 효과가 있는 천 연물 제제에 응용 가능성이 있음을 확인하였다.