• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.240-244
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• 2003

A novel integrated method for increasing dissolved oxygen concentration in culture media has been developed. It involves adding hydrogen peroxide to the medium, which is then decomposed to oxygen and water by catalase and adding vegetable oil to the medium as antifoam agent and oxygen vector. A new apparatus for automated addition of hydrogen peroxide to the bioreactor to keep the dissolved oxygen concentration constant over the range $10-100%\;{\pm}\;5%$ was tested. A significant increase (over threefold) of cultivation time was obtained while the dissolved oxygen concentration remained stable ($30%\;{\pm}\;5%$). Therefore, use of corn oil mixed with Ca-stearate as oxygen vector and antifoam and hydrogen peroxide as oxygen source to control excessive foam that was generated by microorganism biosurfactant, GB16-BS produced at Bacillus sp. GB16 cultivation was appropriate for stable cultivation.

• Journal of Acupuncture Research
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• v.21 no.3
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• pp.179-191
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• 2004

It is well known that acupuncture is effective for treatment of gastric disease in human. For years, we have been utilizing a electro-acupuncture(EA) in attempt to manage gastric symptoms. However, the data on clinical effectiveness is conflicting and the action of acupoints is unclear. The purpose of this study was to investigate the effects of manual and electro acupuncture(EA) at acupoints of ST 36 and GB 34 on the serum gastrin level by radioimmunoassay in rats. All of acupuncture treatment was applied to the acupoints for 30 min during 3 days. Manual acupuncture with both acupoints resulted in increased gastrin serum level when compare to control group treated with only anesthesia. Either high (100 Hz) and low (2 Hz) frequency EA at ST 36 decreased gastrin serum level compared with control group, but EA at GB 34 conversely increased. In EA with device was designed stimulating only acupoint(New EA), either low frequency on ST 36 and high frequency on GB 34 unusually increased gastrin serum level compared to control group. The results of this experiment suggest that many factors, such as the selection of acupoints, the manipulation and the specification of acupuncture device, are capable of affecting acupuncture effects.

• Korean Journal of Optics and Photonics
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• v.14 no.4
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• pp.454-459
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• 2003

We report the first demonstration of 10 Gb/s wavelength conversion in a Mach-Zehnder interferometric wavelength converter monolithically integrated with a loss-coupled DFB probe source. The integrated device is fabricated using a BRS (buried ridge stripe) structure with an undoped InP clad layer on the top of a passive waveguide to reduce high propagation loss. The device exhibited a static extinction ratio of 11 dB. Good performance at 10 Gb/s is obtained with an extinction ratio of 7 dB and a power penalty of 2.8 dB at a 10$^{-9}$ bit error rate.

• ETRI Journal
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• v.45 no.1
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• pp.163-170
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• 2023

We report an electroabsorption modulator (EAM)-integrated distributed Bragg reflector laser diode (DBR-LD) capable of supporting a high data rate and a wide wavelength tuning. The DBR-LD contains two tuning elements, plasma and heater tunings, both of which are implemented in the DBR section, which have blue-shift and red-shift in the Bragg wavelength through a current injection, respectively. The light created from the DBR-LD is intensity-modulated through the EAM voltage, which is integrated monolithically with the DBRLD using a butt-joint coupling method. The fabricated chip shows a threshold current of approximately 8 mA, tuning range of greater than 30 nm, and static extinction ratio of higher than 20 dB while maintaining a side mode suppression ratio of greater than 40 dB under a window of 1550 nm. To evaluate its modulation properties, the chip was bonded onto a mount including a radiofrequency line and a load resistor showing clear eye openings at data rates of 25 Gb/s nonreturn-to-zero and 50 Gb/s pulse amplitude modulation 4-level, respectively.

• Korean Journal of Materials Research
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• v.30 no.4
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• pp.184-196
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• 2020

In this study, effects of carbon and nickel on microstructure and low temperature Charpy impact properties of HSLA (high strength low alloy) steels are investigated. To understand the complex phase transformation behavior of HSLA steels with high strength and toughness before and after welding processes, three kinds of HSLA steels are fabricated by varying the carbon and nickel content. Microstructure analysis, low temperature Charpy impact test, and Vickers hardness test are performed for the base metals and CGHAZ (coarse-grain heat affected zone) specimens. The specimens with the lowest carbon and nickel content have the highest volume fraction of AF, the lowest volume fraction of GB, and the smallest GB packet size. So, the low temperature Charpy absorbed energy of the CGHAZ specimen is the highest. The specimens with increased carbon and nickel content have the lowest volume fraction of AF, the highest volume fraction of GB, and the largest GB packet size. So, the low temperature Charpy absorbed energy of the CGHAZ specimen is the lowest.

• Korean Journal of Materials Research
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• v.30 no.3
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• pp.123-130
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• 2020

In this study, two types of thick steel plates are prepared by controlling carbon equivalent and nickel content, and their microstructures are analyzed. Tensile tests, Vickers hardness tests, and Charpy impact tests are conducted to investigate the correlation between microstructure and mechanical properties of the steels. The H steel, which has high carbon equivalent and nickel content, has lower volume fraction of granular bainite (GB) and smaller GB packet size than those of L steel, which has low carbon equivalent and nickel content. However, the volume fraction of secondary phases is higher in the H steel than in the L steel. As a result, the strength of the L steel is higher than that of the H steel, while the Charpy absorbed energy at -40 ℃ is higher than that of the L steel. The heat affected zone (HAZ) simulated H-H specimen has higher volume fraction of acicular ferrite (AF) and lower volume fraction of GB than the HAZ simulated L-H specimen. In addition, the grain size of AF and the packet sizes of GB and BF are smaller in the H-H specimen than in the L-H specimen. For this reason, the Charpy absorbed energy at -20 ℃ is higher for the H-H specimen than for the L-H specimen.

• Korean Journal of Acupuncture
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• v.27 no.2
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• pp.57-70
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• 2010

Objectives : To investigate the meaning and the importance of needling or moxibustion- prohibited acupoints in Chimgugapeulgyeong(鍼灸甲乙經). Methods : We found needling or moxibustion-prohibited acupoints in Chimgugapeulgyeong, then investigated the causes of the prohibitions from the various literatures and the anatomical structures near the acupoints. Results : In Chimgugapeulgyeong, the needling and moxibustion-prohibited points were ST9, ST17, ST32, CV5, and CV15. The needling-prohibited points were LU2, LI13, ST12, BL56, KI2, KI7, TE8, TE19, GB3, CV8, GV24, and jwagak(左角). The moxibustion-prohibited points were LU3, LU8, ST1, ST7, ST8, ST30, ST33, BL5, BL6, BL15, BL30, TE18, TE21, TE23, GB22, GB33, GB42, GV6, GV15, GV16, GV17 and GV25. The major cause of developing prohibited needling or moxibustion was due to the possibility to damage vessels or organs near them; other causes were side effects brought by applying wrong stimulating method or inducing women sterilized. Conclusions : The prohibition of needling or moxibustion on the points found in Chimgugapeulgyeong had acceptable causes. Therefore the techniques of needling or moxibustion on the acupoint should be performed with care.

• Journal of Mushroom
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• v.19 no.4
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• pp.341-346
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• 2021

Simple sequence repeats (SSRs) were isolated from major Pleurotus pulmonarius cultivars in Korea, namely 'HS47' (monokaryon, gamete of 'Santari'), 'GB19' (monokaryon, gamete of 'Santari'), 'Hosan,' 'Yeoleumneutali1,' 'Sambok,' 'Gangsan,' 'Yaksan,' 'Jasan,' 'Hyangsan,' and 'Yeoleumneutali2,' and characterized via HiSeq genome sequencing and bioinformatic analysis. The genome sizes of the monokaryons 'HS47' and 'GB19' were estimated to be 37.3 and 37.2 Mb, respectively, and those of the other dikaryotic cultivars ranged from 47.1 to 61.1 Mb. A total of 711 (smallest) and 1,106 (1.5 times the smallest) SSRs were found in the 'HS47' and 'Gangsan' genomes, respectively. Hexanucleotide and octanucleotide motifs accounted for the top two fractions of all SSRs. CGA/TCG, A/T, and CTC/GAG were the most frequently detected nucleotides in the SSRs. Most of the SSRs were 21~30 nucleotides long (hypervariable for application), accounting for 70% of all lengths of SSRs.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.1
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• pp.33-41
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• 2011

The objective of this study was to compare the shear bond strengths of five dentin adhesive systems cured with three different light curing sources. Seventy five noncarious permanent teeth were collected and stored in an 0.1% thymol solution at room temperature after extraction. The tested adhesives were: Adper Scotchbond Multi-purpose Plus Adhesive (SM) Adper Single bond 2 (SB), Clearfil SE Bond (SE), Adper Prompt L-Pop (PL), G-Bond (GB). And three light curing unit systems were used: Elipar Free light 2(LED), OptiLux 501 (Halogen), Flipo (PAC). For the shear bonding test, the labial and lingual surfaces of permanent teeth were used. To obtain a flat dentin surface, the labial and lingual surfaces of the teeth were sanded on SiO2 with number 600 grit and then divided into 15 groups of 10 surfaces each. All samples were theromocycled in water $5^{\circ}C$ and $55^{\circ}C$ for 1000 cycles. The results were as follows: 1. When cured with Freelight 2, the shear bond strength of SM was significantly higher than that of PL, GB (p<0.05), whereas no significant difference was found among those of any other bonding agents. 2. When cured with Optilux 501, the shear bond strength of SM was significantly higher than those of any other bonding agents (p<0.05), whereas no singnificant difference was found among those of andy other bonding agents. 3. When cured with Flipo, the shear bond strength of SM was significantly higher than those of SB, SE, GB (p<0.05), whereas no significant differences was found among those of any other bonding agents. 4. For comparison according to three different light cure unit system, except SB and GB, each three dentin bonding agents showed no significant difference. For SB, only Freelight 2 was significantly higher than the others, with no significant difference between Optilux 501 and Flip. For GB, Statistically significant difference was found only between Freelight and Flipo.

• Journal of Nutrition and Health
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• v.49 no.3
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• pp.144-152
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• 2016

Purpose: This study was conducted in order to develop morning bread using powdered citrus peels and to examine the effect of its several biological activities for 12 weeks in overweight adults ($$BMI{\geq_-}23$$) living in dormitories of Chonbuk National University. Methods: Control bread was prepared using the same formula except for replacing the wheat flour with 3% citrus peel powder. Subjects were classified according to two groups: Intake group of 3% citrus peel powder fortified morning bread (n = 30) and general morning bread (n = 30). Results: The results of our study showed no significant effects of citrus peel powdered morning bread on anthropometric indices and biochemical characteristics among overweight adults. Despite the slight reduction in total-cholesterol, LDL-cholesterol, GOT, and GPT (p < 0.05), no significant differences in changes of these values were observed between the two groups. Conclusion: The short duration of our intervention might have resulted in the lack of any significant effect. Therefore, conduct of further studies with longer duration is warranted in order that the results from this study can be utilized as a basis for the development of food products with citrus peel powder.