EBR-II사용후핵연료의 파이로건식처리공정에 의해 발생된 우라늄의 순도에 대한 포괄적인 분석을 수행하였다. 분석결과를 미국 아이다호 국립연구소 및 한국원자력연구원의 협력과제 하에서 한국과 미국의 저준위 폐기물 기준으로 비교하였다. 미국의 저준위 폐기물 기준은 우라늄 동위원소를 포함하지 않으나, 한국의 경우는 포함하는 것으로 조사되었다. 분석결과 EBR-II 우라늄 생성물 내에서 저준위 기준을 초과하는 유일한 알파 핵종은 우라늄 동위원소가 아니라 Pu-239였다. 생성물 내의 Pu 오염은 개량된 염증류공정을 통한 예비실험 결과 획기적으로 줄일 수 있음을 알 수 있었으며, 보다 공정을 개선 시킨다면 제안된 기술을 이용하여 미국의 저준위 기준을 만족시킬 수 있을 것으로 판단된다

Gryon japonicum (Ashmead), an egg parasitoid of Riptortus clavatus (Thunberg) is an economically important pest of various crops. As a conservational biological control, non-viable refrigerated eggs of R. clavatus were released to enhance parasitism by the parasitoid in soybean field. Since fenitrothion is an insecticide broadly used against R. clavatus, we investigated the effect of fenitrothion on the parasitization of refrigerated host eggs by G. japonicum. The acute toxicity of fenitrothion was compared with seven pesticides by topical application, exposure to residue, and oral ingestion. Fenitrothion, spinosad, cyfluthrin, carbosulfan and thiamithoxam caused 100% mortality within 24 hours by topical application. Fenitrothion was also highly toxic to G. japonicum when ingested orally. In sublethal effects of fenitrothion on G. japonicum in refrigerated and fresh host eggs, adult emergence of G. japonicum decreased by 12% and 34%, respectively, compared to control when the fenitrothion was applied on 8th day after parasitization. Parasitism on refrigerated eggs after a day of fenitrothion spray was higher as compared to the fresh eggs. However, parasitism on both refrigerated and fresh eggs significantly reduced when the parasitoids were provided with the fenitrothion sprayed eggs after an hour. In conclusion, there is no negative effect of fenitrothion on the parasitization by G. japonicum.

The attachment and adhesion of RAW 264.7 and MC3T3-E1 cells to titanium (Ti) discs with various degrees of roughness was investigated. The attachment, adhesion, and proliferation of these cells were evaluated after 4 hr, 24 hr and 7 day incubations. Both RAW 264.7 and MC3T3-E1 cells showed a time-dependant correlation between attachment and adhesion on the surface of the titanium discs. Both types of cells tended to have higher survival rate on these discs as the surface roughness increased. The percentage of adherent inflammatory RAW 264.7 cells was greater than MC3T3-E1 cells at 24 hr, but this was reversed at 7 days in culture. The morphology of osteoblastic MC3T3-E1 cells at 24 hr, determined using a surface emission microscope (SEM), appeared flattened and spread out while inflammatory RAW 264.7 cells were predominantly spherical in shape. The adhesion of both cell types on the titanium discs was dependant on the levels of fibronectin adsorbed on the disc surface, indicating that serum constituents modulate the efficient adhesion of these cells. Our data indicate that the cellular response to the titanium surface is dependent on the types of cells, surface roughness and serum constituents.

This study was conducted to investigate the effects of type of the sugar supplemented to the extender on the vigor, viability and intact acrosomal rates of frozen-thawed dog spermatozoa. The ejaculated semen was diluted with TRIS-citric acid extender containing 200mM TRIS, 73mM citric acid, 6% (v/v) glycerol, 20% (v/v) egg yolk, 1% (v/v) antibiotics (streptomycin/penicillin), 44 mM sugar, which was either glucose, fructose or glucose-fructose combination, and distilled water to make the final volume of 100ml. Extended semen samples were cooled at for an hour, packaged in 0.25ml straws, equilibrated for 10 minutes in liquid nitrogen vapor, and frozen in liquid nitrogen. Samples were thawed by placing straws into water for 120 seconds. After thawing, vigor, viability and intact acrosomal rates of frozen-thawed semen were compared according to type of sugar. No significant differences were observed between glucose and fructose groups. In addition, combination of the 2 sugars also did not show any significant differences in the vigor, viability and intact acrosomal rates. In conclusion, glucose and fructose were equally efficient as sugar supplements for freezing extender.