• Research in Plant Disease
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• v.24 no.3
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• pp.193-201
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• 2018

Pectobacterium carotovorum subsp. carotovorum (Pcc) causes bacterial soft rot on a wide range of crops worldwide, especially in countries with warm and humid climates. This study was conducted to establish an efficient screening method for resistant cultivars of radish (Raphanus sativus) to bacterial soft rot. Resistance degrees of 60 commercial radish cultivars to the Pcc KACC 10421 isolate were investigated. For further study, six radish cultivars (Awooriwoldong, YR Championyeolmu, Jeonmuhumu, Bitgoeunyeolmu, Sunbongaltari, Housecheongok) showing different level of resistance to the bacterium were selected. The development of bacterial soft rot on the cultivars was tested according to several conditions such as incubation temperature, seedling stage of radish, inoculum concentration to develop the disease. On the basis of the results, we suggest that an efficient screening method for resistant radish to Pcc is to inoculate twenty-day-old seedlings with a bacterial suspension of Pcc at a concentration of $8{\times}10^5cfu/ml$ and then to cultivate the plants in a growth room at $25^{\circ}C$ and 80% RH with 12-hour light per day.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.427-436
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• 2008

Purpose. The objective of this study was to evaluate the behavioral response and assess the effectiveness of additional intranasal (IN) and submucosal (SM) administration of midazolam during pediatric sedation for dental procedure. Material and methods. Thirty-three cases of healthy (ASAⅠ), uncooperative children aged from 24 to 72 month old at pediatric dental clinic of Ewha Womans University Hospital were selected for this study. Children received oral chloral hydrate 50 mg/kg with hydroxyzine 1.0 mg/kg. After waiting for 45 minutes, midazolam 0.2 mg/kg was administrated via IN route and via SM route randomly maintaining 50% of $N_2O$. A pulse oximeter and a capnograph were used for measuring vital signs ($SpO_2$, PR, RR, $EtCO_2$) throughout the sedation. Behavioral response was evaluated as Quiet (Q), Crying (C), Movement (M) or Struggling (S) in every 2 minutes for 40 minutes. Results. There were also no statistically significant differences in vital signs of the two groups. The behavioral response for the first ten minutes during sedation was a statistically significant difference (P < 0.05) between the two groups. After the first ten minutes, it was revealed that there was no significant difference. Conclusion. This study demonstrated that the addition of IN midazolam to the combination of oral chloral hydrate with hydroxyzine and nitrous oxide/oxygen inhalation is as safe and effective as that of SM midazolam in pediatric sedation for dental procedure.

• Research in Plant Disease
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• v.15 no.3
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• pp.187-192
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• 2009

Pepper powdery mildew, Leveillula taurica is one of the most important pathogens of pepper in the greenhouses and fields in Korea and is becoming a worldwide disease. These experiments were carried out to investigate the optimal germination, disease development conditions, disease incidence and effective inoculation methods of pepper powdery mildew. The incidence of powdery mildew was investigated throughout the country based on the major pepper growing areas in 2009. The average rate of infected leaves ranged from 15.3% to 81.8% in greenhouses and fields. Powdery mildew incidences were more severe in greenhouses than those of fields. The optimal temperature for conidial germination was $25^{\circ}C$ and showed the highest germination at 6 hs after treatment. The range of temperature for germination was $10^{\circ}C$ to $35^{\circ}C$. Temperature of greater than $30^{\circ}C$ and below $20^{\circ}C$ affected the abnormal germination and germ tube elongation. The optimal relative humidity for germination and germ tube elongation was 85% and germination increased as relative humidity increased. Disease development started 8 days after inoculation and showed the highest disease severity at 15 days in greenhouse and field regardless of varieties. Among three different inoculation methods tested the spore dropping method was better than touching with infected leaves and spraying with spore suspension. However, the method has limitation in mass inoculation due to the amount of time consumed.

• Journal of the Korean Magnetics Society
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• v.15 no.1
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• pp.42-47
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• 2005

Nanocrystalline Nd-Fe-B powder was synthesized by a new thermochemical process that combined with past reduction-diffusion process and spray-dry process. In this process, Ca reduction process is vary important due to formation of hard magnetic$Nd_{2}Fe_{14}B$ phase from various oxides by Ca powder. Therefore, the final products are essentially affected a shape, size, and composition etc. of the Ca reduced powders. Ca reduction was performed to way that raw powders just mixed with Ca powder in proper ratio unlike to compress into compact. The powders after mixture-type Ca reduction mainly composited with $Nd_{2}Fe_{14}B$ phase even relativily low reaction temperature ($800^{\circ}C$) and all particle size of powder were distributed less than 1 ${\mu}m$ except for powder after Ca oxides as magnetic properties of powders after cake-type Ca reduction, with the consequence that high magnetic properties has been expected. The magnetic properties of powders prepared by mixture-type Ca ruduction, with the conseqence that high magnatic properties has been expected. The magnetic properties of powders prepared by mixture-type Ca reduction process showed $_iH_c$ = 5.9 kOe, $B_r$ = 5.5 kG, (BH)max = $Nd_{2}Fe_{14}B{\to}Nd_{2}Fe_{17}B$ decomposition by violent exothermic reaction during washing.

• Journal of the Korean Magnetics Society
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• v.15 no.5
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• pp.270-275
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• 2005

Dust cores (compressed powder cores) of $Fe-6.0wt\%Si$ alloy with a size of $35\~180\;{\mu}m$ in diameter have been prepared by phosphate coatings and annealings at $600\~900^{\circ}C$ for 1 h in nitrogen atmosphere. Further the magnetic and mechanical properties of the powder cores were investigated. As a general trends, the compressive strength and core loss decreased with the increase in annealing temperature. When annealed at $800^{\circ}C$, the compressive strength was 15 kgf, the permeability and quality factor were 74 and 26, respectively. Moreover the core loss at 50 kHz and 0.1 T induction was $750\;mW/cm^3$, and the percent permeability under the static field of 50 Oe was estimated to be about 78. In addition, the cut-off frequency in the cure representing the frequency dependence of effective permeability was measured to be around 200 kHz. These properties of the $Fe-6.0wt\%Si$ alloy dust cores could be considered to be due to the good insulation effect of iron-phosphate coats, the decrease in magnetocrystalline anisotropy and saturation magnetostriction and the increase in electric resistivity.

• The Korean Journal of Pesticide Science
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• v.17 no.1
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• pp.27-32
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• 2013

Damage of tea bagworms, Eumeta minuscula was observed for the first time from grape leaves of grape (varieties: Cambell Early and M.B.A.) from a vinery at Gumho-up, Gyeongsan, Gyeongbuk on 31 August, 2012. Activity of insecticides [Bacillus thuringiensis var. kurstaki (serotype IIIa, IIIb) WP, chlorantraniliprole 5% GP, methoxyfenozide 21% SC, spinetoram 5% GP, and spinosad 10% GP] was tested on fourth instar larvae of Eumeta minuscula in laboratory. Mortality of 4th instar of Eumeta minuscula was higher when treated with spinosad 10% WG (88.7%) and spinetoram 5% WG (67.7%) sprayed with field recommended concentration using a home sprayer in laboratory. Mortality decreased as the concentration decreased, however leaf damage rate was significantly different between the one-fourth rate and the control. Spinetoram 5% WG and spinosad 10% WG showed 63.7 and 55.7% respectively mortality of fourth instar Eumeta minuscula in field. Though these two insecticides could be used for the control of bagworms on grape, a more effective insecticide needs to be found.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.1-6
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• 1977

The 'Kresek' disease in Korea caused by Xanthomonas oryzae was first found from eight counties in Jeon-nam and Kyungnam province in 1976. The study has been carried mainly on the grouping of pathogens and reproduction of the symptoms on Milyang #23, the variety had shown severe damages at the fields, by using the isolates from Hwa-sun and Kwang-san counties where the first epidemics took place. 1. The 'Kresek' disease was found mainly on Milyang #23, a new variety, at Hwa-sun, Mu-an, Kang-jin. Yung-am, Gog-sung counties in Jeon-nam province and Jin-yang county in Kyung-nam province. 2. The groups of 'Kresek' causing pathogens were the same of those producing bacterial leaf blight symptoms such as group I , II, IN and V of Xanthomonas oryzae. 3. Seventeen out of 21 isolates from Hwa-sun county where the first and severe damage found belonged to group IV, 2 to group II and 2 to group V All of 5 isolates from Kwang-san county belonged to the group IN. 4. The 'Kresek' type symptom could reproduced within 5 days after inoculation to seedlings by using root tut, spray and needle inoculation methods. j. The most of effective method for the inoculation was root cut, and then were spray and needle method. respectively. The higher concentration of inoculum produced the higher disease incidence.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.262-269
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• 2008

This study was performed to investigate the toxicity of 39 registered insecticides to the susceptibility, systemic effect, and residual effect and control effect against Pine sawyer beetle, Monochamus saltuarius. Eleven kinds of chemicals such as fenitrothion, fenthion, phenthoate, phosphamidon, dinotefuran, actamiprid, clothianidin, thiacloprid, thiamethoxam, esfenvalerate+fenitrothion, and fipronil were showed 100% insecticidal activity both in body spray and twig dipping bioassay. Among these chemicals, fenitrothion and fenthion were showed 100% insecticidal activity when sprayed at 4000 times diluted solutions, and phenthoate, thiacloprid, thiamethoxam and fipronil were showed 100% insecticidal activity when sprayed at 2000 times diluted solution. Root systemic effect was showed 100% mortality in phosphamidon, clothianidin, thiamethoxam, and 77.7% in thiacloprid. In residual effect, fenitrothion and thiamethoxam were showed 80% mortality fifteen days after treatment (DAT), and fenthion, phosphamidon, clothianidin were showed 80% mortality ten DAT, fenitrothion, thiamethoxam, fipronil showed 100% mortality in seven DAT, thiacloprid was showed 100% mortality in three DAT. Fenthion and phenthoate were showed 100% mortality one DAT. In the control effect, 6 kinds of chemicals were showed 100% mortality one DAT and all chemicals showed 100% mortality three DAT.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.1
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• pp.1-7
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• 2016

Highly porous polymethyl methacrylate (PMMA) microspheres impregnated by $TiO_2$ powder were prepared by spray drying method. The particle size and the porosity were controlled by optimizing the co-solvent ratio and the polymer concentration. $TiO_2$ powder was impregnated into the microspheres upto 74.6 wt% content based on the weight of the resultant $PMMA/TiO_2$ microspheres. SEM images showed that $TiO_2$ powder was well distributed throughout the inside of the microsphere. EDX mapping showed that the Ti signal was well detected from every part of the microspheres, which was the evidence of the formation of the $PMMA/TiO_2$ composite. Hg porosimetry result showed that the porosity was found to be over 50% regardless of the $TiO_2$ contents. The final product was found to have high oil-absorbing capacity and great hiding power, both of which are key properties in designing the microsphere materials for make-up cosmetics application.

• Journal of the Korean Ceramic Society
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• v.39 no.5
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• pp.503-510
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• 2002

Silicon carbide candle filters for the pressurized fluidized bed combustion system were fabricated by extrusion process. Carbon black was added to control the porosity. Inorganic additives such as clay and calcium carbonate were added to exhibit appropriate strength. Silicon carbide layer with a finer pore size (mean pore diameter ~$10{\mu}m$) was coated on the silicon carbide support layer (mean pore diameter ~$47{\mu}m$, porosity ∼40%). After that, the filter was sintered at 1400${\circ}C$ in air. We evaluated the filtration performances of the filter at 500${\circ}C$ and $5kgf/cm^2$ of pressure. As a result, high separation efficiency, >99.999% was measured. It is expected that silicon carbide candle filter can be successfully used for the pressurized fluidized bed combustion system.