The damaged spent fuel rods must be stabilized by encapsulation or dry re-fabrication technologies before geological disposal. For applying the dry re-fabrication technology, we manufactured a vertical type furnace to perform the fuel material recovery from damaged fuel rods by oxidative decladding technology. As driving forces to accelerate oxidative decladding rate, magnetic vibration and pulse hammering generated by a pneumatic cylinder were used in this study. The oxidative decladding efficiency and recovery rate of fuel oxide powder with rod-cut length, oxidation temperature and time, oxygen concentration, and gas mixtures were investigated using simfuel rod-cuts in a vertical furnace for fuel material recovery and powder quality improvement. The oxidative decladding was performed for 2.5-10 h as following operation parameters: simfuel rod-cut length of 50-200 mm, oxidative temperature from 450 to 580°C, oxygen concentration of 49.5 or 75.6%, and gas mixtures in O2/Ar or O2/N2. In magnetic vibration, oxidative decladding was progressed only at bottom portion of fuel rodcut. Whereas, oxidative decladding in pulse hammering was occurred at both top and bottom portions of fuel-rod. In pulse hammering method, the oxidative decladding conditions to declad rod-cuts of 50- 200 mm in length were established to achieve both decladding efficiency of ~100% and fuel material recovery rate of > 99%. These conditions were as follows: oxidation temperature and time at 500°C and 2.5-10 h, oxygen concentration at 75.6% under O2/N2 gas mixtures. As operation conditions for a pneumatic cylinder, stroking, actuating, and waiting times were 0.5, 3, and 12 s.

The damaged spent fuel rods must be stabilized by encapsulation or dry re-fabrication technologies before geological disposal. For applying the dry re-fabrication technology, we manufactured a vertical type furnace to perform both fuel material recovery from damaged fuel rods by oxidative decladding and sinterability improvement of fuel powder by repetition of oxidative and reaction treatment. A horizontal type furnace provides only a diffusion-controlled reaction resulting in longer reaction time and decreasing amount of powder for oxidation and reduction, whereas a vertical type furnace with a submerged gas distributor gives rapid reaction due to flowing gas-solid contact by fluidization. For observation of fluidization behaviors of uranium oxides at room temperature, fluidized column was prepared with transparent cylindrical tube, pressure transmitter and gas flow meter. Number of size of orifice holes was determined by equations in Fluidization Engineering [D.Kunii, O. Levenspiel]. Before uranium oxide test, as surrogates, WO2 (10.8 g/cm3) and Ta2O5 (8.2 g/cm3) powder similar to density of UO2 (10.96 g/cm3) and U3O8 (8.3 g/cm3), respectively were used to achieve fluidization operation conditions in the region from minimum to expanded fluidization. Fluidization behaviors and pressure drop of powder bed was observed according to operation parameters such as gas velocity, number and size of orifice holes, and powder amount.

The spotted wing drosophila(Drosophila suzukii)is one of the serious fruit pest that has a wide range of fruit crops like blueberries, cherries and grapes. It came up the larvae cause dagmage by feeding on the pulp inside fruits and berries and spotted wing drosophila also has a adversely affect export to Austrailia and New zealand as a quarantine pest. This study conduct to survey occurrence of drosophila spp. from 2016 to 2018 on harvest period of grapevine in vinyard of Okcheon ,Yeongdong and fruit packing place for export to New zealand and USA. Vinegar and wine mixture was used to attract fruits flies. We also investigated to what color is the best stimulus to catch a vinegar flies. Our result shows that significant differences were observed in total flies trapped in red and black colors. This study will contribute to future research for monitoring and control drosophilid flies.

Earthworms, especially Eisenia andrei, are cultivated for a variety of purposes including waste disposal and compost production. In this study, bacteria from earthworm gut were cultured and the dominant species identified. Subsequently, we isolated bacteriophages able to lyse the isolated gut bacteria. Two dominant genera of gut bacteria, Aeromonas sp. and Citrobacter sp. were identified by using MALDI-TOF MS analysis and a library was constructed to find lytic phages. Phage EF1 showed lytic activity for C. freundii and two Citrobacter isolates, C. braakii and C. murliniae. These 3 species have similar sensitivities to EF1. Several aspects of the life cycle of EF1 were investigated by using C. freundii under optimal growth conditions. EF1 infects C. freundii with a moderate latent period, approximately 25 min, and a large burst size averaging 5 × 109 per infected cell. Moreover, the antimicrobial activity of EF1 was well maintained under diverse conditions including a broad temperature range of 40°C to 50°C and a wide pH range of 4 to 11. In conclusion, the results indicate that earthworm casting contain a wide range of bacteria species, for which there are various corresponding bacteriophages.

전 세계적으로 인구가 증가함에 따라 유전자변형(GeneticallyModified; GM) 작물의 생산 역시 가파르게 상승하고 있다.국내에서 GM 작물의 재배가 아직까지는 승인된 바가 없지만식품, 사료, 가공용으로 많은 양이 수입되고 있다. 1. 결과적으로 GMO의 수입이 매년 증가하여 수송과정이나가공과정에서 비의도적인 방출이 발생하며, 주변환경에서 자라고 있는 일반 재배품종으로의 유전자이동 등 국내 자연환경에 미칠 수 있는 영향이 우려되고 있다. 2. GM 작물 중 우리나라에 가장 많은 양이 수입되는 GM옥수수의 비의도적인 방출을 확인하기 위해 2009년 7월부터9월까지 국내 곡물항구와 사료공장을 중심으로 모니터링을 수행하였다. 3. 조사는 주로 개방된 항구의 곡물저장고 지역과 사료공장으로 가는 수송경로에서 옥수수 종자와 자라고 있는 옥수수식물체를 수집하여 진행되었다. 4. PCR 분석을 통해 14개의 GM 옥수수 식물체와 수집된종자를 발아시켜 얻은 식물체 샘플 26개에서 GM 옥수수 유전자가 발견되었다. 5. 낙곡에 의한 GM 옥수수 종자의 유출이나 식물체가 자연환경에서 자라고 있는 것이 우리나라의 생태계에 어떠한 영향을 줄지 예측하기는 어렵지만, 법적으로 GMO를 철저히 관리하도록 되어 있으며, 사회적으로도 수입 GMO를 안전하게 관리하고 있다는 인식을 높이기 위해 주기적인 GMO의 모니터링이 수행되어야 할 것으로 판단된다.

Alzheimer’s disease (AD) is a fatal disorder wherein patients suffer from sensory, motor, and cognitive loss. Currently, the identification and validation of biomarkers for diagnosing AD and other forms of dementia are increasingly important. Olfactory dysfunction is present in patients diagnosed with Alzheimer’s disease or idiopathic Parkinson's disease. Alzheimer’s patients show neuropathological changes in areas of the brain central to the olfactory processing center, suggesting the theoretical importance and potential diagnostic utility of investigating functional changes in olfaction in these patients. However, the usefulness of olfactory screens to serve as informative indicators of Alzheimer’s is precluded by the lack of knowledge regarding neural and molecular mechanisms underlying olfactory dysfunction onto Alzheimer's diseases. To test these ultimate questions, we used molecular and electrophysiological recording techniques to find out the difference of olfactory responses and AD related protein expression patterns by using fly model, Drosophila melanogaster that over-expresses the human β -amyloid, tau protein. We postulated that such flies would present with progressive olfactory impairments compared with age-matched wild type control flies. In this study, our hypothesis is that there is a correlation between olfactory deficits and the spatial expression pattern of β-amyloid and tau protein deposition. Therefore, we demonstrate a specific concentration of lesions in central olfactory structures such as antenna and Maxillary palps. Our study indicates that deficits on olfactory identification may occur in AD, which will be valuable as an indicator of neuropathogenesis.

The silkworm (Bombyx mori), as an industrial insect, possesses a high economic value. Casual discrimination and accumulated genetic information of silkworm varieties are essential ground for the practical utilization and long-term conservation. In this study, nine available microsatellite loci were successfully genotyped from ~50 silkworm strains preserved in Korea. According to genotyping analysis, we obtained 3 ~ 16 alleles per locus, with an average of 7.4, the observed heterozygosity ranging from 0.04 to 0.98, and the polymorphic information content (PIC) ranging from 0.06 to 0.88, revealing that some loci are highly variable. Among 54 strains 13 strains were casually identified by the presence of 17 strain-specific apomorphic alleles. Furthermore, 30 among remaining strains contained strain-specific allele combinations that are also apomorphic to each strain, allowing us to discriminate each of these from other strains by genotyping of multiple loci. These results collectively suggest that the silkworm microsatellite DNA is actually and potentially important molecular marker for the discrimination of the silkworm strains that are preserved as hundreds in Korea, as more loci are genotyped.

Three acetylcholinesterases (AChEs) were identified from the pinewood nematode, Bursaphelenchus xylophilus. Sequence comparison with known AChEs in conjunction with three-dimensional structure analysis suggested that all BxAChEs share typical characteristics of AChE at the major catalytic structures. BgAChE3 was most predominantly transcribed and then followed by AChE1 and AChE2. Immunohistochemistry using anti-BxAChEs antibodies revealed that BxAChE1 is most widely distributed whereas BxAChE2 exhibits more localized distribution in neuronal tissues. BxAChE3 was detected from entire body together with some limited tissues, including mouth parts and alimentary lining, and determined to be the only soluble AChE, suggesting its localization in hemolymph or/and extracellular space. Kinetic analysis of in vitro expressed BxAChEs revealed that BxAChE1 has the highest substrate specificity whereas BxAChE2 has the highest catalytic efficiency with BxAChE3 having the lowest catalytic efficiency. Interestingly, presence of BxAChE3 in the pool of BxAChEs significantly reduced the inhibition of BxAChE1 and BxAChE2 by inhibitors. Knockout of BxAChE3 by RNAi significantly increased the toxicity of nematicides, suggesting the protective role of BxAChE3 against these toxicants. Based on several features, including tissue distribution, expression level, substrate kinetics and inhibition property, it appeared that BxAChE1 is the major AChE with the function of postsynaptic transmission whereas BxAChE3 has been evolved to acquire the function of chemical defense, perhaps intrinsically against secondary toxic compounds from host pine trees, such as α-pinene and limonene. BxAChE2 appears to play a role in post-synaptic transmission in specialized neurons but its detailed physiological function still remains to be elucidated.

Background : The main ingredients of bed soil specialized for ginseng, which is often used in cultivation of young ginseng, are peat moss, vermiculite and cocopeat. These ingredients are imported from overseas countries because they are not produced in Korea, and thus play an important role in pricing of the bed soil. The bed soil products show satisfactory ability to retain moisture but, are known to require different containers and water management methods depending on the components of the soil and the crops to be cultivated. However, proper studies on cultivation of young ginseng in greenhouses are yet to be conducted, and research data on water management methods and irrigation amount for box culture of young ginseng are largely unavailable. Methods and Results : To establish the proper method of irrigation for cultivation of young ginseng, young ginseng were cultivated while providing water once a week through the method of drip irrigation and the method that combines drip irrigation and sprinkler irrigation. To establish the proper amount of water required, each box is provided with 2 ℓ, 3 ℓ and 4 ℓ of water respectively and the growth and development of both above and below aerial parts were examined after 45 days. The growth and development of both above and below aerial parts of young ginseng did not show any statistically significant differences between the two irrigation methods but, the young ginseng provided with water through the method that combines drip irrigation and sprinkler irrigation showed a relatively superior growth. Conclusion : Based on the above results, the proper method of irrigation for greenhouse cultivation of young ginseng is to combine the sprinkler irrigation - before budding - and the drip irrigation - after budding. The young ginseng showed the most satisfactory growth when provided with 4 ℓ water once a week, while those provided with less water – 2 ℓ - showed poor growth. For short-term cultivation of 45 days, the growth and development of young ginseng showed little difference regardless of the irrigation methods and the amount of water provided.