Molten Salt Reactor (MSR) is one of the 4th generation nuclear power systems which is its verified technology in physically and chemically. Among the various salts used for MSR system, the eutectic composition of NaCl-MgCl2 system maintains the liquid state at around 450°C, in the same time, it has high solubility for nuclear fuel chlorides. This characteristic has high advantage for lowering the operating temperature for the MSR, which could reduce the problem of hightemperature corrosion by salt for structural materials significantly. In particular, since MgCl2 has the similar standard reduction potential with nuclear fuel, is used as a surrogate for, many basic researches have been conducted for verifying characteristic of MgCl2. It is well-known that main short-advantage of MgCl2 is hygroscopic properties. MgCl2 changes to MgCl2-xH2O state easily by absorbing moisture in air condition. The hydrated MgCl2 is producing MgOHCl by thermally decomposing at high temperature, the formed MgOHCl corrodes structural materials, even small amount of MgOHCl gives significant damage. Therefore, the purification of MgCl2 has been required for long-term operation of MSR using MgCl2 as a base salt. In this study, the purification of eutectic composition salt for NaCl-MgCl2 has been mainly performed by considering its thermodynamic properties and electrochemical characteristic, and the experimental results have been discussed.

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 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 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.

This study was conducted to estimate the effect of home or hetero fermentative lactic acid bacteria(LAB) on chemical composition, fermentation quality, and aerobic stability of rye silage. Rye forage was harvested at dough stage(28.9% of dry matter), chopped to 3-5 cm length, and divided into 4 piles for different inoculations as treatment, following 1) No additives(CON); 2) Lactobacillus plantarum at rate of 1.5 x 105 cfu/g of fresh forage(LP); 3) L. buchneri at rate of 1.2 x 105 cfu/g of fresh forage(LB); and 4) Mixture of LP and LB at 1:1 ratio(MIX). Rye silage was ensiled into 20 L bucket silo in quadruplicate for 0, 1, 4, 7, and 100 day periods. After 100 days of ensiling, the silage treated with LB had lower acid detergent fiber content(p<0.05), but higher in vitro dry matter digestibility(p<0.05). The LB and MIX reduced (p<0.05) pH more rapidly than CON and LP across the ensiling days, but had no difference on 100 days. Silage treated LP had lowest(p<0.05) acetic acid, but highest(p<0.05) propionic acid. In contrast, LB treated silage had highest(p<0.05) acetic acid, but lowest(p<0.05) propionic acid with the absence of butyric acid. On microbial count, LP treated silage had lowest(p<0.05) LAB, yeast, and aerobic stability, whereas LB and MIX treated silages had highest(p<0.05). Mold was not detected across all silages. Therefore, it could be concluded that heterofermentative LAB solely or combo with homofermentative LAB might improve in vitro dry matter digestibility, fermentation characteristics, and aerobic stability of rye silage harvested at dough stage.

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.

Honeybees have faced many diseases which treaten bee colony including a serious population decline phenomenon called Colony Collapse Disorder (CCD). Nosema ceranae is a pathogen cause nosemosis, which is now wide spread around the world. According to the genome sequencing for N. ceranae, it has been identified that the presence of machinery for RNA silencing. Microsporidia N. ceranae that are obligated intracellular parasites depend on their host for energetic and metabolic needs. Here we selected the several genes from mitosome of N. ceranae to develop RNAi for the control of Nosema. Especially, TOM40, FNR1, FNR2 and Nar1 were chosen. After infection of N. ceranae, the Honeybee were treated with RNAi either by using only one or combining two or more. The infection rate and specific gene silecing in Nosema were analyzed.

The two-spotted spider mite, Tetranychus urticae, is one of the most important pests of crops. However, chemical acaricides are not always effective and their continuous use has resulted in resistance among two-spotted spider mite populations. To reduce or replace use of chemical acaricides, the entomopathogenic fungi having acaricidal activity were investigated. As results, 12 isolates could be selected from 342 isolates of fungi against two-spotted spider mite. To show the multiple roles of entomopathogenic fungi against plant pathogen, the antimicrobial activity of selected 12 isolates were evaluated to plant pathogenic bacterium Ralstonia solanacearum and fungus Botrytis cinerea. Various antimicrobial activities were observed against these plant pathogens. Consequently, these entomopathogenic fungi would be offered an alternative for dual control agents against the two-spotted spider mite and plant diseases.

Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea and dehydration in pigs with high mortality. PEDV is belong to Coronavirus, enveloped, single-stranded, positive-sense RNA virus. PEDV particles were composed of four structure proteins such as a glycosylated peplomer (spike, S) protein, envelope (E), glycosylated membrane (M) protein, and unglycosylated RNA-binding nucleocapsid (N) protein. Many of previous studies talk about this four structure proteins have a great potential to diagnosis and prevent PEDV. In this study we investigated expression of these structure proteins using the bacterial and baculovirus expression system. In bacterial expression system, our results showed that structure proteins fused polyhedrin and intein gene were expressed higher than non-fusion structure proteins. The expressed fusion proteins were used to immune mice for generating a polyclonal antibodies. In baculovirus expression system, co-infection of insect cells with these four recombinant baculoviruses led to self-assembly of virus-like particles as demonstrated by Transmission electron microscopy. They were confirmed by western blot analysis using pre-made polyclonal antibodies. Finding in this study may provide important information for vaccine and diagnostic development.

Insects are among the most diverse groups of animals on the planet, representing more than half of all known living organisms. These insects are found in nearly every environment. Although humans regard certain insects as pests and attempt to control them using insecticides, most insects perform complex ecological functions, and provide either direct or indirect economic benefits to humans. Recently, the importance of insects used as food sources or as pets has increased in many countries, including Korea. In addition, several insects have a strong influence on people's emotion. Insect-mediated mental healthcare program is designed to help people who have disorders with physical, behavior and development. Children who have mental disorder, the experimental group that was provided with an insect-mediated mental healthcare program over a total of 8 sections, one section per week, 60 minutes per section, followed by pre-test and post-test. They responded to therapeutic effect after the completion of the program. Further research on the basis of this study is expected to help children with emotional therapy in other areas.

The population of managed honey bees has been dramatically declining the recent past in worldwide. The one of most common disease of bees is nosemosis, the nosemosis is caused by microsporidia in the genus Nosema. Nosema apis and N. ceranae have been described as honeybee pathogens. These microsporidia are highly evoloved fungi with an obligately intracellular parasitic lifstyle. The disease causes significant detriment to honey production and results in economic losses. In our knowledge, Fumagillin is the only antibiotic approved for control of nosemosis in honey bees, however this antibiotic may have unintended effects on the honey bee host, ultimately contributing to increased prevalence and pathogenicity of Nosema. Therefore, we screened anti-Nosema substances from entomopathogenic fungal culture filtrates using in vitro polar tube germination assay. These fungal metabolites are employed as antibiotic agents. As results, Total 3 samples (23% of 13 total samples) showing the germinating inhibition against N. ceranae. This screening method may be useful for the detection of anti-Nosema substances from various samples and selected samples in this study may be a good feature to be used in the development of a new biocontrol method of nosemosis.

Porcine parvovirus (PPV), a member of the genus Parvovirus, family Parvoviridae, is a significant causative agent in porcine reproductive failure, causing serious economic losses in the swine industry. PPV is a non-enveloped virus and its capsid is assembled from three viral proteins (VP1, VP2, and VP3). The major capsid protein, VP2 is the main target for neutralizing antibodies in PPV. When VP2 was expressed in large amounts, it assembled into virus-like particles (VLPs) similar in size and morphology to the original virions. In this study, we generated the recombinant Bombyx mori nucleopolyhedrovirus (BmNPV) to express the VP2 protein. Expression of the VP2 protein was analyzed by SDS-PAGE and Western blot. The recombinant VP2 protein of approximately 64 kDa was detected by both analyses. The formation of VLP by recombinant VP2 was confirmed through transmission electron microscopy examination. The purified VP2 protein assembled into spherical particles with diameters ranging from 20 to 22 nm.

Insect constitute the largest and most diverse group of animals on world and also serve as the hosts or nutrient sources. In addition, several insects have a strong influence on people's emotion. To utilize the preference and interest of insects in the field of mental healthcare, a survey study was conducted with individual living in Korea. As results, the most people had a high preference and interest of insect, but some were disagreeable to the insect itself. The preference and interest of insect were high on male, adult and practician experienced insect-related events than female, student and non-practician, respectively. The most favored insects were familiar or pet insects such as Papilio xuthus, Lucanus maculifemoratus, Allomyrina dichotoma and Lampyridae. These results may be useful to develop a healing program for mental healthcare using insects. Further research is needed to determine the effects of these insect in the mental therapy for this purpose.

This study investigated the densification behavior of rhenium alloys including W-25 wt.%Re and Re-2W-1Ta (pure Re) during sintering. The dilatometry experiments were carried out to obtain the in-situ shrinkage in H2 atmo-sphere. The measured data was analyzed through shrinkage, strain rate and relative density, and then symmetricallytreated to construct the linearized form of master sintering curve (MSC) and MSC as a well-known and straightforwardapproach to describe the densification behavior during sintering. The densification behaviors for each material were ana-lyzed in many respects including apparent activation energy, densification parameter, and densification ratio. MSC witha minimal set of preliminary experiments can make the densification behavior to be characterized and predicted as wellas provide guideline to sinter cycle design. Considering the results of linearized form and MSC, it was confirmed thatthe W-25 wt.%Re compared to Pure Re is more easily densified at the relatively low temperature.