• Progress in Medical Physics
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• v.16 no.3
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• pp.155-159
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• 2005

As a part of implantable device in body, a transcutaneous energy transmission system has been developed. It would be desirable to tansfer electrical energy to implantable devices transcutaneously. The distance between transcutaneous transformer windings are approximately equal to the thickness of the human's skin, nominally between 10$\~$20 mm. Class-E resonant amplifier is used to drive a primary coil for high efficiency. Maximum current is above 50 mA at any frequency. The developed system shows that the circuit operates correctly at each frequency; 500 kHz, 1 MHz and 4 MHz.

• Journal of Korea Foundry Society
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• v.26 no.6
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• pp.249-257
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• 2006

The effects of alloying element and the condition of heat-treatment on the strength of squeeze-cast Al-3.0 wt%Si alloy were investigated. The strength of the alloy without grain refinement was increased with increase Cu content upto 3.0 wt% and rather decreased beyond that. The tensile strength of the alloy with grain refinement increased with Cu content upto 3.0 wt% and not changed beyond that. The strength of the alloy without grain refinement increased with the Mg content. The tensile strength with grain refinement increased with the Mg content upto 0.50 wt% and then decreased beyond that. The strength of the grain refined alloy increased by individual and simultaneous additions of Cu and Mg and the maximum strength was obtained with Al-3.0 wt%Si-4.5 wt%Cu-0.50 wt%Mg alloy. The optimum heat-treatment condition for this alloy was obtained.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.225-230
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• 2004

We employed single cell gel electrophoresis method (comet assay) to analyze the degree of nucleus-DNA damage in the leaves of red pepper (Capsicum annuum L.) seedlings exposed to $^{60}$ CO v-radiation stress. Nucleus-DNA damage was measured as the ratio of tail length (T) to head length (H) in individual comet image isolated from pepper leaf cell. The T/H ratio of control-cells and treated-cells at 50 or 100 Gy were 1.28 and 3.54 or 3.39, respectively, suggesting that nuclei of pepper cells were severely damaged in the integrity of DNA strand by the treatment of enhanced v-radiation. The percentage of head-DNA in control-cells was 76.8%, whereas those of 50 and 100 Gy treated-cells were 55.9% and 59.9%, respectively. Pretreatment of low dose (4 to 20 Gy) radiation to seeds decreased DNA-damage in the leaves of seedlings treated with high dose radiation at 50 or 100 Gy. In this experiment, we developed a sensitive, reliable and rapid method for evaluating genotoxic effect in the nuclei of plant cells by employing comet assay.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.989-992
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• 2022

This study was conducted to investigate the efficacy of larval stages of three species, namely, Tenebrio molitor, Protaetia brevitarsis seulensis, and Ptecticus tenebrifer larvae, in degrading poultry manure, specially, broiler and duck manure. The survival rates of larvae were also noted. For the experiment, T. molitor (n=300), P. brevitarsis seulensis (n=60), and P. tenebrifer (n=300) hatched larvae were randomly divided into six groups with three replicates. The degaradation efficacy tests were then performed for 30 days in a laboratory. The test groups were as follows: T1, 110 g broiler manure + T. molitor larvae (n=50); T2, 110 g duck manure + T. molitor larvae (n=50); T3, 125 g broiler manure + P. brevitarsis seulensis larvae (n=10); T4, 125 g duck manure + P. brevitarsis seulensis larvae (n=10); T5, 105 g broiler manure + P. tenebrifer larvae (n=50); and T6, 105 g duck manure + P. tenebrifer larvae (n=50). The groups showed significant efficacy in degrading broiler and duck manure (p<0.05). The highest survival rates were recorded for T. molitor larvae in both manure types [T1 (92.67%) and T2 (50%)], followed by P. brevitarsis seulensis larvae (T4, 40%) and P. tenebrifer larvae (T6, 14.67%) in duck manure. Next, the survival rates of P. brevitarsis seulensis (T3) and Ptecticus tenebrifer larvae (T5) in broiler manure were 0%. In conclusion, these results point to the feasibility of using insect larvae to degrade broiler and duck manure.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.14-19
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• 2009

This study was performed to characterize the lipases produced from Gelidibacter sp. YH333 and Vibrio sp. YH339 isolated from mud flats for industrial application of a lipase. Amount of the lipases secreted from the isolated strains was sharply increased in the proportion of increase of number of the cells. The lipases produced from the isolated strains were constitutively secreted from the cells. The lipase activity of Gelidibacter sp. YH333 was higher than that of Vibrio sp. YH339 to p-nitrophenyl esters. The lipases produced from both strains showed the highest activity in p-nitrophenyl laulate among various p-nitrophenyl esters. The molecular weights of the lipases from Gelidibacter sp. YH333 were about 50 KDa and 25 KDa, respectively. Molecular weight of the lipase from Vibrio sp. YH339 was about 50 KDa.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.167-174
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• 1980

Anionic polymerization of 2-pyrrolidone was carried out via PPBC/KOH catalysis. The effects of PPBC/KOH mole ratio, KOH concentration and temperature on polymerization have been investigated. It was observed that the highest rate of polymerization and maximum conversion were obtained when PPBC/KOH mole ratio was around 0.5. The maximum conversion and the highest viscosity were obtained when the concentration of KOH was 2 mole percent. It was also found that while the rate of polymerization at $50^{\circ}C$ was higher than at $30^{\circ}C$ in the initial stage of polymerization, the conversion and viscosity were decreased as polymerization time was extended. The rate constant $(k_p)$ of polymerization was determined by least square method; the values of $k_p$ obtained were $22.4\;l/mole{\cdot}hr\;at\;30^{\circ}C\;and\;191.9\;l/mole{\cdot}hr\;at\;50^{\circ}C$, respectively.

• Journal of Environmental Science International
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• v.28 no.7
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• pp.639-643
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• 2019

We aimed to evaluate antithrombotic efficacy of Protaetia brevitarsis extract during 21 days. Rats (SPF rat, weight 240~260 g) were divided into 16 groups (5 rats per group), they were: control group and Protaetia brevitarsis extract groups with dose of 0.1, 0.5, 1, 2.5, 5, 10, 25, 50, 75, 100, 200, 250, 500, 750, 1,000 mg/kg kg of body weight. Thromboplastin time (PT) and activated partial thromboplastin time (aPPT) as antithrombotic efficacy were tested in this animal experiment (at 7, 14 and 21 days). Overall, the admistration dose of Protaetia brevitarsis extract over 50 mg/kg at 7, 14 and 21 days for PT and over 25 mg/kg at 7, 14 and 21 days for aPPT tented to be longer than that of other groups. In addition, the optimal admistration doses of Protaetia brevitarsis extract to improves antithrombotic efficacy were 75, 100, 200 and 250 mg/kg at 7, 14 and 21 days for PT (p<0.05) and 50 and 100 mg/kg at 7 days, 75 mg/kg at 14 days, or 50, 100, 200 and 250 mg/kg at 21 days for aPPT (p<0.05). It can be concluded that Protaetia brevitarsis extract at optimal levels have antithrombotic efficacy.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.993-997
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• 2022

This study was conducted to evaluate the structure and composition (i.e., pH, moisture, total-N, pathogens, and volatile fatty acids) of broiler and duck manure treated with larvae of three insect larvae, namely, Tenebrio molitor, Protaetia brevitarsis seulensis, and Ptecticus tenebrifer. Hatched Tenebrio molitor (n=300), Protaetia brevitarsis seulensis (n=60), and Ptecticus tenebrifer (n=300) were used in this study; specially, the larvae were divided into six treatments with three replicates. The treatments were as follows: T1: 110 g broiler manure + Tenebrio molitor larvae (n=50), T2: 110 g duck manure + Tenebrio molitor larvae (n=50), T3: 125 g broiler manure + Protaetia brevitarsis seulensis larvae (n=10), T4: 125 g duck manure + Protaetia brevitarsis seulensis larvae (n=10), T5: 105 g broiler manure + Ptecticus tenebrifer larvae (n=50), and T6: 105 g duck manure + Ptecticus tenebrifer larvae (n=50). For all the larval treatments, the following results were observed: The moisture content of the duck manure treat with three insect larvae was higher than that of the broiler manure (p<0.05), whereas broiler manure had a higher pH (p<0.05). In addition, the total nitrogen content of broiler manure was higher than that of duck manure (p<0.05). However, the insect larvae did not significantly affect pathogens (E.coli and Salmonella) and the volatile fatty acids (p>0.05). In conclusion, the use of the three insect larvae to create organic nitrogen compost using poultry manure is feasible.

• Korean Journal of Plant Resources
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• v.31 no.3
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• pp.195-201
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• 2018

This study was executed to evaluate the phenolic content, DPPH radical scavenging rate, and the cytotoxic effect in human cancer cell, 3T3-L1 cell from C. lanceolata extracts at various ethanol concentration. Total polyphenol and flavonoid content of the C. lanceolata at various ethanol concentration showed the high amount in 70%, 100% ethanol extract. The DPPH radical scavenging activity progressively increased in a dose-dependent manner, and showed the highest in 100% ethanol extract. The cytotoxic effect against human cancer cell of the C. lanceolata was higher in 50% and 70% ethanol extracts. In particular, the cytotoxic effect in MCF-7 cell was relatively higher than in other cells. The $IC_{50}$ (concentration causing 50% cell death) value showed the highest on MCF-7 cell ($538.39{\mu}g/m{\ell}$ in 70% ethanol extract, and exhibited significant activity against Hela cell ($637.87{\mu}g/m{\ell}$, Calu-6 cell ($728.64{\mu}g/m{\ell}$. The extract of 70% ethanol at $1,000{\mu}g/m{\ell}$ exhibited a pronounced cytotoxic effect on 3T3-L1 cell comparable to that of the other extracts, and reduced in a concentration-dependent manner.

• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.201-206
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• 2003

Differential responses of red pepper plant and cultured cells to enhanced ${\gamma}$-ray($^{60}$ Co) and ultraviolet(UV) stress were investigated. In seed treatment, 1 Gy of ${\gamma}$-ray increased seedling dry weight up to 19.1%, but 50 Gy treatment markedly ingibited seed germination and subsequent growth of seedling. UV treatment to seed did not change the germination ability of seeds and the growth of seedlings regardless of duration of UV treatment until 24 hrs. In case of UV treatment to seedlings, plant injury was seriously progressed even after the seedlings were returned to no UV condition, and eventually all the leaves showed chlorosis by the stress. However, progress of plant injury by ${\gamma}$-ray stress slower than that caused by UV stress, and even at the high dose of ${\gamma}$-ray 50 Gy, did not caused the cholrosis of stressed plant leaf. Amount of electrolytes leakage from plant leaf by UV treatment for 24hrs was increased up to 28.8 folds in comparison with untreated control, whereas that of 50 Gy of ${\gamma}$-ray was increased only 1.2 folds. UV stress induced the production of capsidiol, antimicrobial phytoalexin, by activation of gene expression involved in capsidiol biosynthesis, such as sesquiterpene cyclase and cyclase and cytochrome P450 hydroxylase in the leaf and cultured cell, but ${\gamma}$-ray stress induced neither the production of capsidiol nor expression of the genes.