As the demand for nuclear power increases as a means to achieve carbon neutrality, concerns about nuclear proliferation have also grown. Consequently, significant researches have conducted to enhance nuclear non-proliferation resistance. Among these research, nuclear material attractiveness is a methodology used to evaluate how appealing a particular material is for potential use in nuclear weapons, based on the characteristics of that material. Existing nuclear material attractiveness assessments focused on materials like U, Pu, and TRU, which could be directly used in the production of nuclear weapons. However, these assessments did not consider how the properties of nuclear materials change throughout the nuclear fuel cycle, with each facility process. This study assumed a scenario of the nuclear fuel cycle of graphite reduction reactors and analyzed including enrichment facilities and PUREX. This study used the FOM (Figure-Of-Merit) method developed by LANL (Los Alamos National Laboratory) for evaluating the nuclear material attractiveness. The FOM formula consists of three parameters such as critical mass, heat content, and dose The critical mass of targe materials and the dose evaluation were conducted using the Monte Carlo N-Particle code. The heat content was calculated using the ORIGEN code embedded in the Scale code. In particular, if U-238 is dominant in the facility’s materials, such as mining and refining facilities, and critical mass evaluation is unpractical. Therefore, 1SQ (Significant Quantity) of that uranium was assumed as the critical mass value for the FOM evaluation, even though 1SQ is not identical to the critical mass As a result of this study, the attractiveness of Pu produced by PUREX among all nuclear fuel cycle facilities was 2.7616, which was the most attractive to be diverted to nuclear weapons. Through this study, it was shown that the proliferation risk of the nuclear facilities in the nuclear fuel cycle and risk of diversion among those facilities.

Se-79, a fission product of uranium, is present in spent nuclear fuel. Selenium is volatilized from the spent nuclear fuel during the pretreatment of pyroprocessing, and a filter composed of calcium oxide can capture gaseous selenium in the form of CaSeO3. Because Se-79 has a long half-life (3.27E5 years) and selenite ions have high mobility in groundwater, they must be immobilized in a chemically stable form for final disposal. This study used a composition of 50 TeO2 - 10 Al2O3 - 10 B2O3 - 10 Na2O - 10 CaO - 10 ZnO (mol%). High-purity powders of TeO2, Al2O3, H3BO3, Na2CO3, CaCO3, and ZnO were used as glass precursors. The mixed powders were placed in alumina crucibles and melted in an electric furnace under an ambient atmosphere at 800°C for 1 h before being cast on a carbon mold. The obtained glasses were ground into fine powders and then mixed with CaSeO3 powders. The powders were melted in alumina crucibles at 800°C for 1 h. To simulate a seleniumcaptured calcium filter, CaSeO3 was synthesized by a precipitation method using sodium selenite (Na2SeO3) and calcium nitrate (Ca(NO3)2) solutions. The glass samples were analyzed by an X-ray diffractometer (XRD). Retention of Se in tellurite glasses was analyzed by an X-ray fluorescence spectrometer (XRF) and inductively coupled plasma (ICP). The chemical durability of tellurite glass was evaluated through the PCT method.

The baculovirus-insect cell expression system has been widely used method for the recombinant protein expression. The present study has several limitation. In this study, we constructed vectors consisting of transcriptional enhanced factor and promoter that improve the expression level. To confirm the usefulness of these vector system, Human papillomavirus (HPV) VLPs have been expressed by baculovirus hyper expression system. HPV VLPs were purified using a CaptoTM Core 700 (GE Healthcare Life Sciences) chromatography approach. Baculovirus hyper expression system production efficiency was influenced by the HPV VLPs production. HPV VLPs vaccination to BALB/c mice induced the generation of antibody confirmed by ELISA. This study could provide improvements on the vaccine production for the development of VLP vaccines high expression of useful heterologous proteins.

The present study evaluated the susceptibility of field populations of Plutella xylostella and Spodoptera exigua larvae to four diamide insecticides—chlorantraniliprole, cyantraniliprole, cyclaniliprole, and flubendiamide. All the four diamide insecticides induced 100% mortality in the populations from Seongju (SJ) and Geochang (GC) when treated at a concentration recommended for P. xylostella. However, a very low insecticidal activity was observed in the population from Pyeongchang (PC) with 42.3% 3 d after treatment with chlorantraniliprole. Further, the populations of S. exigua from Cheongju (CJ), Jindo (JD), and Yeonggwang (YG) were not completely controlled by the 4 diamide insecticides. A comparison of susceptibility of S. exigua larvae to chlorantraniliprole between 2014 and 2017 showed that chlorantraniliprole induced 100% mortality in all populations in 2014, whereas a very low insecticidal activity was observed among the populations in 2017. This study can serve as a basis to control pests effectively using diamide insecticides.

The population of managed honeybees has been dramatically declining the recent past in worldwide. N. ceranae causessignificant detriment to honey production and results in economic losses critically. In our knowledge, Fumagillin is theonly antibiotic approved for control of nosemosis in honeybees. In this study, to select isolate with anti-Nosema activityagainst N. ceranae. Entomopathogenic fungi cultural filtrates were screened using in vitro polar tube germination assay.These fungi cultural filtrates were used to evaluate the safety of honeybees and their inhibition of nosemosis. As a result,P. marquandii 364 and Pochonia sp. 60 showed inhibitory activity on the growth of N. ceranae in honeybees and didnot significantly affect the survival rate of honeybees. These may be employed as antibiotic agents and a good featureto be used in the development of new biocontrol agents of nosemosis.

The baculovirus expression vector system (BEVS) is an effective and widely used system for the production of recombinantproteins in insect cells or larvae. However, the expression efficiency of recombinant proteins using the polyhedrin promotercould not acquire the protein yields observed for native polyhedrin. In this study, we tried to develop hyper expressionvector by the optimal combination of previously reported various enhancer factors. The selected enhancer factors for optimalexpression consists homologous region5 (hr5), VP39 promoter and burst sequences. Seven recombinant viruses were madeto compare EGFP expression level. Each recombinant viruses showed different expression levels respectively, and themost of expression level was observed with higher than those of the previous vectors. This study suggests a new optionfor hyper expression of useful recombinant protein using the BEVS.

The two-spotted spider mite, Tetranychus urticae, and gray mold disease caused by Botrytis cinerea, are importantpest and plant disease. To control these, many people have been relied on chemical methods for a long time. However,their continuous use has resulted in resistance of pest and disease. To surmount or avoid these problems, we evaluatedantifungal activity of the selected fungi with high virulence to mite to explore the potential for the dual control of notonly T. urticae but also B. cinerea. To maximize the use of spores and cultural filtrates, the virulence to mite was evaluatedusing culture products, and effective culture condition was investigated against blastospore production and antifungal activity.Consequently, the 2 fungal isolate selected in this study were confirmed to have diverse potential and would be usedeffectively for dual control agents against the two-spotted spider mite and plant diseases

Viral particles of Porcine epidemic diarrhea virus (PEDV) consist of a four structural proteins. Among them Spikeprotein mediated responsible for receptor binding and membrane fusion during viral infection and therefore the main targetof neutralizing antibodies. Virus-like particles (VLPs) are consisted of one or more viral structural proteins, and theirmorphologies closely resemble those of the native virus. VLPs have no virulence and can elicit robust immune responsesas compared with inactivated or live-attenuated virus vaccines. Thus, in this study, we tried two methods for VLP constructionin Bombyx mori, one is traditional method and the other is chimeric VLP method using the influenza matrix protein.Both methods could produce successfully PEDV VLPs.

The baculovirus expression vector system (BEVS) is an effective and widely used method for the production of recombinant proteins in insect cells or larvae. However, the expression efficiency of foreign proteins using the polyhedrin promoter could not obtain the protein yields observed for native polyhedrin. To enhance the production efficiency of foreign protein in baculovirus expression system, the effects of various enhancer factor were investigated by fusion expressing them with the enhanced green fluorescent protein (EGFP). As a hyper expression factor, the optimal hyper BEVS was constructed by combining Hr5 sequence, VP39 promoter and Burst sequences. Additionally, the proteins expressed by the hyper expression system was markedly increased. This study suggests a new option for higher expression of useful foreign recombinant protein using the BEVS.

The green peach aphid, Myzus persicae, is one of the most important pests of vegetable crops worldwide. This species cause direct damage by feeding on plant nutrients and indirect damage as transmits many virus vectors. The control of aphid has relied on the use of chemical insecticides and their intensive use over many years has led to the development of resistance. To surmount or avoid these problems, we screened the entomopathogenic fungi against green peach aphid and evaluated their virulences. Several entomopathogenic fungal isolates were selected with high virulence to green peach aphid. Additionally, the antimicrobial activity of the selected fungal isolates was tested and analyzed to phytopathogens. Consequently, these entomopathogenic fungi would be used effectively for dual control agents for the green peach aphid and phytopathogen.

Recombinant proteins including a polypeptide fusion partner, termed affinity tag, to facilitate the purification of the target polypeptides are widely used. However, the affinity tag must be removed from the target after the purification process. Recently, the Synechocystis sp. PCC6803 DnaB mini-intein (Ssp DnaB mini-intein) is widely used in Escherichia coli expression systems as the solution of this problem. The Ssp DnaB mini-intein can be induced simply by shifting of pH and temperature, offering a benefit to cleave a peptide bond without using a protease or chemical reagent. Although the utility of this novel tag is widely studied in E. coli, there is no report yet in baculovirus expression vector system (BEVS). In this study, we generated several recombinant baculoviruses to express foreign proteins with Ssp DnaB mini-intein. In conclusion Ssp DnaB mini-intein was good tag also in BEVS with more advantages.

Recombinant baculovirus genome that absence part of ORF1629 has used to enhance efficiency of recombinant virus selection because a role of ORF1629 is believed to essential for viral replication in insect cells. It can be recovered by recombination with a transfer vector containing a complete ORF1629. Some recombinant bacmids were generated for this purpose. Recombinant bacmid GOZA, one of them, has a mini-F replicon for Escherichia coli and the partial ORF1629 gene. By accident, we could observe the replication of ApGOZA singly in Sf9 cells. Produced virus from ApGOZA was investigated for the existence of truncated ORF1629 not intact ORF1629 by PCR amplification and genomic sequencing. Also, we could observe the replication of AcGOZA alone in Sf9 cells. To analyze the influence of truncated ORF1629, the viral growth, BV production and polyhedral formation were conducted comparing to wild type virus and recombinat virus containing intact ORF1629. The results suggested the probability that ORF1629 is not essential for replication.

Canine parvovirus (CPV), a member of the genus Parvovirus, family Parvoviridae, is a significant causative agent in Canine reproductive failure, causing serious economic losses in the pet industry. The major capsid protein, VP2 is the main target protein for neutralizing antibodies in CPV. When VP2 was expressed using baculovirus, it was produced abundantly and assembled into virus-like particles (VLPs) similar in size and morphology to the original virions. It was named as CPV-VLP. Additionally, p35 sequences of canine distemper virus (CDV) as T-helper epitope were fusion-expressed with each of N-term, C-term or both sides of CPV-VP2. Production of double antigenic recombinant protein and formation of VLPs were analyzed by SDS-PAGE and transmission electron microscopy, respectively.