• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1255-1261
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• 2006

An alkaliphilic bacterium, Bacillus sp. strain BK, was found to produce extracellular cellulase-free xylanolytic enzymes with xylan-binding activity. Since the pellet-bound xylanase is eluted with 2% TEA from the pellet of the culture, they contain a xylan-binding region that is stronger than the xylan-binding xylanase of the extracellular enzyme. The xylanases had a different molecular weight and xylan-binding ability. The enzyme activity of xylanase in the extracellular fraction was 6 times higher than in the pellet-bound enzyme. Among the enzymes, xylanase had the highest enzyme activity. When Bacillus sp. strain BK was grown in pH 10.5 alkaline medium containing xylan as the sole carbon source, the bacterium produced xylanase, arabinofuranosidase, acetyl esterase, and $\beta$-xylosidase with specific activities of 1.23, 0.11, 0.06, and 0.04 unit per mg of protein, respectively. However, there was no cellulase activity detected in the crude enzyme preparation. The hydrolysis of agricultural residues and kraft pulps by the xylanolytic enzymes was examined at 50$^{\circ}C$ and pH 7.0. The rate of xylan hydrolysis in com hull was higher than those of sugarcane bagasse, rice straw, com cop, rice husk, and rice bran. In contrast, the rate of xylan hydrolysis in sugarcane pulp was 2.01 and 3.52 times higher than those of eucalyptus and pine pulp, respectively. In conclusion, this enzyme can be used to hydrolyze xylan in agricultural residues and kraft pulps to breach and regenerate paper from recycled environmental resources.

• Clinical and Experimental Reproductive Medicine
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• v.32 no.4
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• pp.301-314
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• 2005

Objective: Rebamipide is a propionic acid derivative that has an action of the inhibition of superoxide production and removal of hydroxyl radical with the sperm incubation and cryopreservation. In the present study, to investigate whether rebamipide is useful to treat male infertility and sterility, the author observed the antioxidative effects in patient with male infertility and also examined its absorption and distribution in rat genital organ. Methods: To measure the distribution of rebamipide in reproductive organ in the rat, carbon indicated rebamipide, $^{14}C-OPC-12759$, was orally administered to 10 Spraque-Dawley rats and its organ concentration in serum, liver, kidney, stomach, duodenum, colon, urinary bladder, seminal vesicle, epididymis and testicle were measured each time after 0.5, 1, 2, 4, 8 and 24 hours by using HPLC fluorescent method. The concentrations in semen were measured by HPLC fluorescent method in a sample of 50 infertile males who took 900 mg of rebamipide daily for 3 months. To measure the antioxidative effect and fertility rate for 3 months, each month before and after the treatment, sperm motility, vitality, the oxygen free radical formation, level of peroxidation, fetilizing capacity of semen sample which were obtained from infertile male patients by masturbation after at least 48 hours abstinence were analyzed by computer assisted semen analyzer, eosin-nigrosin stain, chemiluminescence, thiobarbituric acid method and hypo-osmotic swelling test. Simultaneously in a sample that wanted baby, both pregnancy and delivery were researched. Results: The $^{14}C-OPC-12759$ concentration in the body of white rats was highest in gastrointestinal organ like stomach, smal intestine and duodenum and followed by genital organ like seminal vesicle, testis and epididymis. The rebamipide concentration in semen of infertile males was $220.77{\pm}327.84ng/mL$ (SD) which showed a large deviation but it was higher than serum which was $126{\pm}76ng/mL$ (SD). In the infertile males, after the treatment with rebamipide, the level of seminal reactive oxygen species (ROS) and lipid peroxidation have significantly decreased in duration of the treatment (p<0.05) and sperm vitality and fertilizing capacity except sperm motility significantly improved on post treatment of 2~3 months (p<0.05). Out of the 41 cases who hoped for pregnancy, 15 cases (36.6%) became pregnant and 12 cases had childbrith, 2 cases had miscarriage and one case is ongoing. The side effect was observed in 1 case (2%) which experienced diarrhea but it was lost spontaneously. Conclusions: We conclude from this study that rebamipide showed relatively high tendancy of absorption and excretion in the genital organ. In infertile males who had elevated ROS in semen, by specifically inhibiting the cell damage from the antioxidation, a way to preserve sperm motility, vitality and fertilizing capacity was confirmed.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1035-1042
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• 2005

Granular Activated Carbon(GAC) is widely used in drinking water treatment. At S and B Water Treatment Plant, GAC is used in place of granular media in conventional rapid filters(GAC Filter-Adsorber) for removal of Disinfection By-products(DBPs). The primary focus of this study is on the performance of existing filter-adsorber, and their operation. It was found that F/A process removed turbidity as effective as sand system. The ratio of Hydrophobic DOM (HPO) and hydrophilic DOM (HPI) fraction in the raw water at S and B WTP was similar. Filter Adsorber presented earlier DOC breakthrough and steady state condition which was contributed by biodegradation during operation period. The removal efficiency of DBPs were used to evaluate the filter performance. The DBPs concentration of F/A treated water was below treatment goal level (THM < $80\;{\mu}g/L$, HAA < $60{\mu}g/L$). The removal efficiency of THM decreased rapidly during operation period. However, HAA were removed steadily regardless of the influent concentration of HAA. These results indicate that the removal of THM depend upon the adsorption mechanism while the removal of HAA depend upon biodegradation as well as adsorption. The decrease of adsorption capacity and characteristic value of GAC may be attributed to the effect of high organic loading, residual free chlorine, coagulants, manganese oxidants and frequently backwashing. This study has confirmed that Filter adsorber process can be considered as effective alternatives for the removal of DBPs, especially HAA.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.15-15
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• 2011

As you know, boron compounds, borax ($Na_2B_4O_5(OH)_4{\cdot}8H_2O$) etc. were known thousands of years ago. As for natural boron, it has two naturally occurring and stable isotopes, boron 11 ($^{11}B$) and boron 10 ($^{10}B$). The neutron absorption $^{10}B$ is included about 19~20% with 80~81% $^{11}B$. Boron is similar to carbon in its capability to form stable covalently bonded molecular networks. The mass difference results in a wide range of ${\beta}$ values between the $^{11}B$ and $^{10}B$. The $^{10}B$ isotope, stable with 5 neutrons is excellent at capturing thermal neutrons. For example, it is possible to decrease a thermal neutron required for the nuclear reaction of uranium 235 ($^{235}U$). If $^{10}B$ absorbs a neutron ($^1n$), it will change to $^7Li+^1{\alpha}$ (${\alpha}$ ray, like $^4He$) with prompt ${\gamma}$ ray from $^{11}B$ $^{11}B$ (equation 1). $$^{10}B+^1n\;{\rightarrow}\;^{11}B\;{\rightarrow}\; prompt \;{\gamma}\;ray (478 keV), \;^7Li+4{\alpha}\;(4He)\;\;\;\;{\cdots}\; (1)$$ If about 1% boron is added to stainless steel, it is known that a neutron shielding effect will be 3 times the boron free steel. Enriched boron or $^{10}B$ is used in both radiation shielding and in boron neutron capture therapy. Then, $^{10}B$ is used for reactivity control and in emergency shutdown systems in nuclear reactors. Furthermore, boron carbide, $B_4C$, is used as the charge of a nuclear fission reaction control rod material and neutron cover material for nuclear reactors. The $B_4C$ powder of natural B composition is used as a charge of a control material of a boiling water reactor (BWR) which occupies commercial power reactors in nuclear power generation. The $B_4C$ sintered body which adjusted $^{10}B$ concentration is used as a charge of a control material of the fast breeder reactor (FBR) currently developed aiming at establishment of a nuclear fuel cycle. In this study for new boron compound, silicon boride ceramics for capturing thermal neutrons, preparation and characterization of both silicon tetraboride ($SiB_4$) and silicon hexaboride ($SiB_6$) and ceramics produced by sintering were investigated in order to determine the suitability of this material for nuclear power generation. The relative density increased with increasing sintering temperature. With a sintering temperature of 1,923 K, a sintered body having a relative density of more than 99% was obtained. The Vickers hardness increased with increasing sintering temperature. The best result was a Vickers hardness of 28 GPa for the $SiB_6$ sintered at 1,923K for 1 h. The high temperature Vickers hardness of the $SiB_6$ sintered body changed from 28 to 12 GPa in the temperature range of room temperature to 1,273 K. The thermal conductivity of the SiB6 sintered body changed from 9.1 to 2.4 W/mK in the range of room temperature to 1,273 K.

• Journal of Chest Surgery
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• v.51 no.1
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• pp.29-34
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• 2018

Background: We evaluated the feasibility and outcomes of pulmonary resection and mediastinal node dissection (MND) by video-assisted thoracoscopic surgery (VATS) following neoadjuvant therapy for stage IIIA N2 non-small cell lung cancer (NSCLC). Methods: From November 2009 to December 2013, a total of 35 consecutive patients with pathologically or radiologically confirmed stage IIIA N2 lung cancer underwent pulmonary resection and MND, performed by a single surgeon, following neoadjuvant chemoradiation. Preoperative patient characteristics, surgical outcomes, postoperative drainage, postoperative complications, and mortality were retrospectively analyzed. Results: VATS was completed in 17 patients. Thoracotomy was performed in 18 patients, with 13 planned thoracotomies and 5 conversions from the VATS approach. The median age was $62.7{\pm}7.9years$ in the VATS group and $60{\pm}8.7years$ in the thoracotomy group. The patients in the VATS group tended to have a lower diffusing capacity for carbon monoxide (p=0.077). There were no differences between the 2 groups in the method of diagnosing the N stage, tumor response and size after induction, tumor location, or histologic type. Complete resection was achieved in all patients. More total and mediastinal nodes were dissected in the VATS group than in the thoracotomy group (p<0.05). The median chest tube duration was 5.3 days (range, 1 to 33 days) for the VATS group and 7.2 days (range, 2 to 28 days) for the thoracotomy group. The median follow-up duration was 36.3 months. The 5-year survival rates were 76% in the VATS group and 57.8% in the thoracotomy group (p=0.39). The 5-year disease-free survival rates were 40.3% and 38.9% in the VATS and thoracotomy groups, respectively (p=0.8). Conclusion: The VATS approach following neoadjuvant treatment was safe and feasible in selected patients for the treatment of stage IIIA N2 NSCLC, with no compromise of oncologic efficacy.

• Journal of Technology Innovation
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• v.22 no.4
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• pp.145-164
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• 2014

Nuclear fusion is one of the most promising options for generating large amounts of carbon-free energy in the future. Major countries such as China, EU, and Japan have established a national plan for DEMO construction and they are implementing it. Korea has started a nuclear fusion research and development by the KSTAR project started in 1995. There are matured needs for a full-scale research and development initiatives to ensure competition with the major countries for DEMO as well as achieve the final goal to commercialize fusion energy. In this paper, we apply the TRL and AHP methods in order to identify the key technologies to conduct DEMO R&D. We propose the priorities of future R&D on DEMO by deriving a core technology in the field. At first, we review the scientific theory of fusion and trend of progress of DEMO activities in major countries. For previous studies, we review TRL and AHP methods to examine the technology classification system of DEMO and identify key technologies. We apply TRL method to identify readiness level of DEMO technologies and AHP to compensate shortcoming of TRL. The key technologies of DEMO to be secured from a synthesis result of the TRL and AHP are burning plasma, plasma facing material, structural material, high frequency heating, neutral particle beam, safety, plasma diagnostic, and simulation technologies.

• Food Science and Preservation
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• v.23 no.2
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• pp.275-282
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• 2016

STAR of STAR (SS 01-04) is a series of drinks that consist of various extracts obtained from Coriolus versicolor, Artemisia capillaris Thunb., Hovenia dulcis, Acanthopanax sessiliflorus, Lycium chinense, Citrus reticulata, Saururus chinensis, Pueraria lobata, Pyrus pyrifolia, and Oenanthe javanica. A purpose of this study was to investigate the hepatoprotective effect of SS 01-04. Antioxidant activity of the drinks was evaluated by conducting a hydroxyl radical-scavenging assay. Cytotoxicity and hepatoprotective potential were determined using HepG2 cells in vitro, while protective effects against acute hepatotoxicity was evaluated in vivo. The antioxidant activity of the SS 01-04 at concentration of 100 and 250 mg/mL was similar to that of $50{\mu}M$ vitamin C. tert-Butyl hydroperoxide (tBHP)-induced production of reactive oxygen species (ROS) was blocked by SS 01, 03 and 04 in a dose-dependent manner. Treatment with SS 04 significantly lowered the serum levels of alanine aminotransferase and aspartate aminotransferase in an animal model of carbon tetrachloride $(CCl_4)-induced$ hepatotoxicity (p<0.05). In addition, SS04 increased glutathione level while decreased malondialdehyde level in the liver considerably (p<0.05). It also inhibited the $CCl_4-induced$ increase in the levels of triglyceride and cholesterol in serum and the liver. These findings indicated that SS 01-04 possessed antioxidant activity and protect against ROS. In particular, SS 04 is potentially highly beneficial in treating liver damage as it scavenges reactive free radicals and boosts the endogenous antioxidant system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.107-110
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• 2001

제철소에서 매년 대량 발생되어 주로 매립처분되고 있는 제강분진의 재활용 방안으로서, 폐수처리분야에 널리 사용되고 있는 펜톤산화공정의 반응촉매원인 Fe 공급원으로서 제강분 진의 활용 가능성에 대한 연구를 수행하였다. 본 연구에서는 포항제철소에서 제철부산물로 발생되는 제강분진을 전처리 없이 산화촉매로 사용하여 김포 수도권 매립지의 침출수 처리 공정에서 펜톤산화조에 유입되는 원수를 대상으로 과산화수소에 의한 산화처리 실험을 수행하였다. 반응은 회분식으로 수행하였으며, 일반적으로 알려진 펜톤산화반응의 주요 반응조 건인 운전 pH, 과산화수소 주입량 및 분할주입, 제강분진의 주입량 등의 변화에 따른 각 조 건별 시간에 따른 반응결과를 알아보았다. 또한 기존의 Fe 공급원으로 사용되고 있는 FeSO$_4$와 처리성능 및 적용조건에 대한 비교 실험도 수행하였다. 침출수 수질변화는 TOC (Total Organic Carbon) analyzer를 사용하여 측정한 TOC값으로 나타냈으며, pH controller 와 정량펌프를 사용하여 HCl과 NaOH주입을 통해 반응기간동안 일정 pH를 유지하였다. 본 연구결과, 최적 pH 조건인 4에서 최대 75% TOC 제거율을 나타내었으며, 대부분의 반응은 30분 이내에 이루어졌다. 주어진 실험조건에서 FeSO$_4$와 비교하여 반응속도와 처리효율에서 향상된 결과를 나타내었으며 반응 후 응집침전실험에서도 보다 높은 처리효과를 얻을 수 있었다. 결론적으로, 과산화수소/제강분진 시스템을 이용한 화학적 산화처리방법은 경제성과 처리성능에서 기존의 펜톤산화공정의 대체방안으로서 향 후 적용가능성이 높을 것으로 기대된다.g, 200 mg/kg, 300 mg/kg의 순서로 함량이 점차 감소하는 결과를 얻을 수 있었다. 이상의 결과를 종합하여 볼 때 가자 메탄올추출물은 PQ 유도독성을 신장 및 폐조직에서 효과적으로 경감시키는 것으로 나타났다.ted retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.181-189
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• 2012

We developed a new high-yield synthesis method of free-standing germanium nanocrystals (Ge NCs) by means of the gas-phase photolysis of tetramethyl germanium in a closed reactor using an Nd-YAG pulsed laser. Size control (5-100 nm) can be simply achieved using a quenching gas. The $Ge_{1-x}Si_x$ NCs were synthesized by the photolysis of a tetramethyl silicon gas mixture and their composition was controlled by the partial pressure of precursors. The as-grown NCs are sheathed with thin (1-2 nm) carbon layers, and well dispersed to form a stable colloidal solution. Both Ge NC and Ge-RGO hybrids exhibit excellent cycling performance and high capacity of the lithium ion battery (800 and 1100 mAh/g after 50 cycles, respectively) as promising anode materials for the development of high-performance lithium batteries. This novel synthesis method of Ge NCs is expected to contribute to expand their applications in high-performance energy conversion systems.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.7-14
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• 2015

The aim of this research is suggesting dry processed bottom ash as a new and economical source of lightweight aggregate for mortar and concrete. The dry process of bottom ash is an advance method of water-free and no chloride because only cooled down by double dry conveyer belt systems. Furthermore, because of relatively slow cooling down process helps burning up the remaining carbon in bottom ash. Using this dry process bottom ash, to evaluate the feasibility of using as a lightweight aggregate for mortar and concrete, two-phase of experiments were conducted: 1) improving shape of the bottom ash, and 2) controlling grade of the bottom ash. From the first phase of experiment, additional abrasing process was conducted for round shape bottom ash, hence improved workability and compressive strength was achieved while unit weight was increased comparatively. Based on the better shape of bottom ash, from the second phase, various grades were adopted on cement mortar, standard grade showed the most favorable results on fresh and hardened properties. It is considered that the results of this research contribute on widening sustainable method of using bottom ash based on the dry process and increasing value of bottom ash as a lightweight aggregate for concrete.