• Restorative Dentistry and Endodontics
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• v.28 no.4
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• pp.341-347
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• 2003

This study was conducted to evaluate the temperature rise on the root surface while the root canal is being obturated using continuous wave of condensation technique. Maxillary central incisor was prepared for repeated canal obturation. Ten thermocouples (Omega Engineering Inc., Stanford, USA) were placed at 1 mm increment from the anatomical root apex. The real temperature of Buchanan plugger was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan and the root surface temperature was recorded during obturation at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings of System B HeatSource (Model 1005, Analytic technologies, Redmond, WA, USA). After completion of the temperature recording, the dentinal-cementum thickness at each sites was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test. The results were as follows. 1. When the temperature was set at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ on the digital display of System B HeatSource, the real temperature of the plugger at the 1mm point from the tip revealed $130.82{\pm}2.96^{\circ}C,{\;}158.00{\pm}5.26^{\circ}C,{\;}215.92{\pm}6.91^{\circ}C{\;}and{\;}249.88{\pm}3.65^{\circ}C$ respectively. 2. The position of 8 mm from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.0l). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was $2.37{\pm}0.09^{\circ}C{\;}at{\;}150^{\circ}C{\;}setting,{\;}3.11{\pm}0.12^{\circ}C{\;}at{\;}200^{\circ}{\;}setting,{\;}3.93{\pm}0.09^{\circ}C{\;}at{\;}250^{\circ}C{\;}setting{\;}and{\;}5.69{\pm}0.15^{\circ}C{\;}at{\;}300^{\circ}C$ setting respectively. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings on digital temperature display of System B HeatSource.

• Korean Journal of Cleft Lip And Palate
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• v.12 no.1
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• pp.1-6
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• 2009

Oronasal fistula are a well-known complication of surgical treatment of cleft palate, occurring most frequently in the alveolus and hard palate. Previous reports have demonstrated that oronasal fistulas, particularly if greater than l cm in diameter, had an adverse effect on speech. The aim of this study was to demonstrate the relationship between the size of the fistula and the influence on velopharyngeal function. The site and size of the fistula were indicated on graph paper with calipers and measured in $mm^2$. Speech assessment was carried out using a Nasometer, VPI articulation differential test, spectrography. Patient whose fistulas affected their speech had significantly larger fistulas than those whose fistulas did not. The study shows that the larger the fistula, the greater the risk of hypernasality and nasal emission, but even small fistulas can cause speech problems. If obstruction of the nasal passage is eliminated in a patient with a previously asymptomatic fistula, it may result in a fistula becoming symptomatic, resulting in hypernasality and nasal emission. In conclusion, even small fistulas can influence speech production and should be considered before any treatment is planned. The study lends support to early closure of oronasal fistulas, particularly before pharyngeal flap surgery is contemplated.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.245-250
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• 2005

This study was carried out to find out how space allowance affect the social behavior of Korean native cattle (Bos taurus coreanae) steers. Twelve Korean native cattle (Bos taurus coreanae) steers were used as subjects, each of which was 30-month-old and observation period was from June to July 2003. Five (T1) and seven (T2) steers were allotted to two pens of $5m{\times}10m$ in a building with slate roof and open sides respectively. They were fed at 09:00 h and 16:00 h, twice a day. The behaviors of steers were recorded from 06:00 h to 17:00 h, using two color CCD cameras (Samsung SDC-411, Korea), one B/W CCD cameras (Samsung SBC-340, Korea), one multiplexer (Samsung SDM-081, Korea) and a time lapse VCR (Samsung SRV-30, Korea). The behaviors of each steer were recorded every 2 min using an instantaneous point sampling method. While the mean percentage of time budget in WA of T1 was lower than that of T2 (p<0.05), the mean percentage of time budget in SF of T1 was higher than that of T2 (p<0.05). When it gets hot, steers in T1 rested from 10:00 h to 14:00 h when it gets cool, showing 40~80% of LD rate while steers in T2 rested from 12:00 h, when it very hot to 17:00 h, showing 20~50% of LD rate, which is relatively low. Steers in T1 were fed from 06:00 h to 08:00 h when it was cool and from 16:00 h to 18:00 h, showing 20~45% of EA rate while steers in T2 were fed from 08:00 h to 14:00 h when it was hot, showing 25~50% of EA rate. In conclusion, it turned out that the number of steers affected their social behavior, and T1 was better environment than T2 in terms of welfare.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.132-136
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• 2007

When alginate lyase gene (aly) from Pseudoalteromonas elyakovii was expressed in E. coli, most of the gene product was produced as aggregated insoluble particles known as inclusion bodies. In order to produce a soluble and active form of alginate lyase, E. coli cells fore cotransformed with the plasmids designed to permit coexpression of aly together with molecular chaperones such as DnaK/DnaJ/GrpE or GroEL/ES chaperones. The results revealed that the coexpression of aly together with DnaK/DnaJ/GrpE chaperone had a marked effect on the production of this protein as a soluble and active form, presumably through facilitating correct folding of alginate lyase protein. The optimal concentration of L-arabinose for the induction of DnaK/DnaJ/GrpE chaperone was found to be 0.05 mg/ml. When DnaK/DnaJ/GrpE chaperone was coexpressed, about 34% in the total alginate lyase was produced in the soluble fraction. By addition of 10% cetylpyridinium chloride, a clear zone around the colony coexpressing aly and DnaK/DnaJ/GrpE chaperone was formed, indicating that the alginate in the medium was hydrolyzed by active alginate lyase enzyme.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.314-320
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• 1996

Antitumouric effect of loquat was investigated treating the extract from leaves, stems, fruits or seeds to normal and cancer cell lines to check by MTT method wheather the cancer cells are spec­ifially attacked. The results are summarized as follows. Water of MeOH extract from each organ were applied to human normal and cancer cell lines, SNU-1 and SNU-C4. The water extract from fruit flesh gave no dffect to normal cell lines by killed all the cancer cell lines. The water extract from fruit flesh was purified by Sephadex LH-20 and separated into 9 fractions which were than applied to 8 cancer cell lines. The eighth fraction out of the 9 fractions gave no effect to normal cells but exerted specific cytotoxicity to breast cancer, stomach and liver cancer cells. The eighth fraction was orally administed and injected to 10 mice each suffering from the abdominal cancer induced by myeloma cells, SP2/0-Ag14. In the groups received the treatment, only one mouse each died in 2 months but the rest survived until the end of the experimental period, which those in the control plot died in 10 to 13 days. The present results confirmed that loquat contained some substance that had specific cytotoxicity to human cancer cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.141-148
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• 2011

This feeding experiment was conducted to investigate the effects of dietary inclusion of various additives on growth performance, hematological parameters, fatty acid composition, gene expression and histopathological changes in juvenile olive flounder (Paralichthys olivaceus). Eleven isonitrogenous (49% crude protein) and isolipidic (10% crude lipid) experimental diets were formulated: no additives (Con); 5% kelp meal (Ke); 10% krill meal (Kr); 1% garlic powder (Ga); 1% citrus meal (Ci); 3% onion powder (On); 1% ginger powder (Gi); 1% mugwort powder (Mu); 1% licorice powder (Li); 1% wasabi powder (Wa); and a mixture (Mix) of these additives. Three replicate groups of juvenile flounder (average weight of 8.5 g) were fed one of the experimental diets to visual satiety twice a day for 15 weeks. The dietary inclusion of additives did not affect survival, weight gain, specific growth rate feed efficiency, daily feed intake, daily protein intake, protein efficiency ratio, hepatosomatic index and visceralsomatic index of the fish. Plasma triglyceride levels were significantly lower in fish fed the Ke, Ga, On, Gi, Mu, Li, and Mix diets than in fish fed the control diet. Plasma glucose, glutamic oxaloacetic transaminase and total cholesterol did not differ among dietary treatments. No significant difference was observed in fatty acid composition and lipid content of the dorsal muscle in fish fed the experimental diets. Myosin gene expression did not differ significantly among treatments after 5 weeks but was significantly lower in fish fed the Kr, Ci, Li, and Mix diets than in control group after 15 weeks. Histopathological analysis showed mild gill hyperplasia and mild necrosis of liver parenchymal cells in several individuals of each experimental group. These conditions were also observed in the control group and were not thought to be related to the inclusion of feed additives. The present findings indicate that the dietary inclusion of additives did not affect growth performance, fatty acid composition, gene expression, and histopathological changes in juvenile flounder. However, plasma triglyceride content may be reduced by supplementation with 5% kelp meal, 3% onion powder, 1% garlic powder, 1% ginger powder, 1% mugwort powder, and the additive mixture.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.522-525
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• 2018

In this paper, we design a UWB / WAS microstrip antenna for wireless local high - speed communication. The substrate of the proposed antenna is FR-4 (er = 4.3) and its size is $30[mm]{\times}30[mm]$. It is designed to have characteristics that can be used in the frequency bands of 3.5 [GHz] and 5.2 [GHz], which are UWB / WAS frequency bands. The simulation was performed using CST Microwave Studio 2014. Simulation results show that the gain is 1.592 [dBi] at 3.5 [GHz] and 2.210 [dBi] at 5.2 [GHz]. The S-parameter also showed a result of less than -10 [dB] (WSWR 2: 1) in the desired frequency band. Microstrip antennas have been miniaturized, high performance, and light weight, and excellent and low cost systems are continuously being developed. In addition, many people use wireless local area network systems used in homes, companies, and public facilities. Since the UWB / WAS technology is proposed according to the development of the system and the demand increase, the antenna that satisfies the above conditions will be designed and the technology applicable to the system will be used more conveniently.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.403-414
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• 2020

Gradient concentrations of Tithonia diversifolia green leaves and phosphate rocks were used to investigate their contributions as a fertilizer to the yield and quality improvement of a rainfed rice cultivar. Six treatments were compared: (1) T0, no fertilization (control); (2) T1, 1.28 g of phosphate rocks; (3) T2, 250 g of organic matter; (4) T3, 500 g of organic matter; (5) T4, 250 g of organic matter + 1.28 g of phosphate rocks; (6) T5, 500 g of organic matter + 1.28 g of phosphate rocks. The results showed that the germination percentage recorded 15 days after sowing varied from 58 - 76% between T0 and T5. The number of panicles ranged between 2 (T0) to 6.3 (T5). Moreover, the recorded length of the panicles ranged between 7.5 (T1) to 15.8 cm (T2), and the number of grains per panicle ranged between 25.5 (T1) to 273.5 (T3). The plant height was significantly increased in the T5 (79.27 cm) group compared to the T1 (33.63 cm) and control treatment (T0) (40.08 cm) groups. Although the plant height in the T2, T3, and T4 groups was slightly lower than the T5 group, the difference was not statistically significant. The average of the grain number per plant was high in the T3 (273.6 grains) group compared to the T1 and T0 (25.5 and 32.8 grains) groups, respectively. These results suggest that the combination of T. diversifolia leaves and phosphate rocks as a natural fertilizer would be beneficial when integrated into soil fertility management strategies and would contribute to improving crop yield and quality.

• The Journal of the Acoustical Society of Korea
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• v.24 no.5
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• pp.271-281
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• 2005

An electromagnetic type shock wave generator suitable for extracorporeal shock wave therapy has been constructed by employing a solenoid coil. The Property of the shock waves produced by the shock wave generator was evaluated using a needle hydrophone. It was shown that, as the capacitor discharging voltage increased from 8 to 18 kV, the Positive Peak Pressure (P+) of the shock wave increased non-linearly from 10 to 77 Wa. In contrast. the negative peak Pressure (f) varied between -3.2 and -6.8 MPa. had its absolute maximum of -6.9 ma at 14 kV The peak amplitudes P+ measured repeatedly under the same voltage setting varied within $5\;\%$ from mean values and this is very small compared to about $50\;\%$ for electrohydraulic type shock wave generators. It could be observed, from the hydrophone signal recorded over 1 ms. several sequential acoustic impulses representing bubble collapses. namely. acoustic cavitation. induced by the shock wave. A technique based on wavelet transformation was used to accurately measure the time delay between the 1st and 2nd collapse known to be closely related to the shock strength. It was observed that the measured time delay increased almost linearly from 120 to $700\;{\mu}s$ with the shock wave Pressure P+ increasing from 10 to 77 MPa.

• Korean Journal of Optics and Photonics
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• v.11 no.5
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• pp.323-329
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• 2000

In this study we have calculated an ideal complex refractive index of a TiN trim used in a layer of anl1reilecnon (I\R) coatmg, [air$ISiO_2ITiNIglass$] in the visible. Also we simulated the rellectance of lwo-layer AR coating by varying the thicknesses of TiN and $SiO_2$ layers, respecl1vely. The simolation results show that we can controllhe lowest reflectance and AR band of tile AR coating. The TIN fihns were fabricated by a RF magnetron sputtering apparalus. The chemical, structural and electrical properties of TiN fih11S were inveshgated by the Rutherford backscattering spech'oscopy (RBS), atomic force microscope (AFM) and 4-point probe. The optical properlies were inve,tigated by the spectrophotometer and vanable angle spectroscopic ellipsometer (VASE). The smface roughness of TiN flhns \vas $9~10\AA$. TIle resistivity of TiN films was TEX>$360~730\mu$\Omega $ cm. The ,toichlOllletry of TiN film was 1'1: O:N = I: 0.65 :0.95 and ilic oxygen wa~ found on ilie smface. With these experimental and simu]al1on resulLs, we deposited duo: two-layer AR coating, [air$ISiO_2ITiNIglass$] and the refleClance was under 0.5% ill the regIOn of 440-650 run. 0 run.