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Oxidative stress on anaerobes

  • Takeuchi, Toru;Shi, Minyi;Kato, Naoki;Watanabe, Kunitomo;Morimoto, Kanehisa
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.142-145
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    • 2002
  • A strict anaerobe, Prevotella melaninogenica is highly sensitive to oxidative stress. Oxidative stress such as exposure to oxygen or addition of hydrogen peroxide, increased 8-hydroxydeoxyguanosine (80HdG), a typical of oxidative DNA damage, and decreased the bacterial cell survival rate. We could detect the generation of reactive oxygen species in P. melaninogenica after exposure to oxygen. UVA irradiation also increased 80HdG in the bacterium. On the other hand, such oxidative stress did not increase 80HdG in a facultative anaerobe. These findings suggest that P. melaninogenica is a suitable material to study the biological effects of oxidative stress, to evaluate antioxidants, and to study the effects of oxygen or reactive oxygen species on molecular evolution.

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A Experimental Study on The Durability and Mechanical of Permanent Form Mortar (비탈형영구 거푸집용 모르터의 내구성 및 역학적 특성에 관한 실험적 연구)

  • 김우재;표순주;임남기;김형남;김성식;이영도;정상진
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.04b
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    • pp.731-736
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    • 1998
  • The dynamics and Durability of Permanent Form Mortar were observed. The results were as the followings. To construct New permanent form, this study constructed permanent form with fiber mortar. In this course glass fiber and polymer, fine aggregate were substituted with river sand and crush sand. To understand material quality effect, flexible mortar and inflexible mortar were tested. According to the microstructure of polymermatrix test by SEM, higher density by Co-matrix effect from polymer addiction was observed. This is considered to increase acid-resistanc, impact proof strenght. In the test of durability of freezing and thawing, polymer mortar was proved to be water proof. It seems to be improved in its characteristics in proportion to increasing W/C ratio. When the W/C ratio is 30%, it is most effective.

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Identification of Floral Type for Honey and Pollen Load (봉밀(蜂蜜) 및 화분하(花粉荷)의 기원식물(基源植物))

  • Suk, Kuy-Duk;Kim, Mi-Kyung
    • Korean Journal of Pharmacognosy
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    • v.14 no.3
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    • pp.83-91
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    • 1983
  • The purpose of this study is concerned with identification of floral type of commercially available honeys and pollen loads. Ikuse's technique was applied to identify the pollen species of honey and pollen loads. Among six kinds of commercially available honeys in Taegu, Korea i.e. Robinia Honey, Brassica Honey, Castanea Honey, Rhododendron Honey, Lespedeza Honey and Multipant Honey, all honeys contained pollens, which were coincident with their trade names given by the apirists, except Lespedeza Honey. The trade name of imported honeys were not given by the plant, from which pollen material and nectar were collected. Among four kinds of these products, pollen was not identified in Clover Honey. A spectrum of honey products added by pollen loads was, of course, wider than simple honey products. The pollen load showed spectrum of pollens including not only those which are specialized for wind pollination, eq. Pinus species and Gramineae, but also contained for insect pollination, eq. rose and leguminous plants.

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Direct Atriopulmonary Anastomosis - Report of 2 cases - (변형 Fontan 술식을 이용한 선천성 심기형증 치험 2)

  • Min, Yong-Il;An, Byeong-Hui;Lee, Dong-Jun
    • Journal of Chest Surgery
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    • v.20 no.3
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    • pp.635-641
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    • 1987
  • Recently, direct atriopulmonary anastomosis was performed in 2 patients without using pericardium or prosthetic material. Case 1 A 13-year-old male patient whose diagnosis was tricuspid atresia [type lb] received direct atriopulmonary anastomosis successfully with good clinical and hemodynamic results. Nine months after operation, he has an increased exercise tolerance. Case 2 A 4-year-old female patient whose diagnosis was DORV with pulmonary atresia in A-V discordance had a formidable surgical challenge. A large-diameter direct atriopulmonary anastomosis was performed after the closure of the right atrioventricular valve. Her postoperative course has been even in 20th postoperative day.

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Characteristics of TVOCs Emission Factors from Chemical and Natural Coating Materials (화학 및 천연페인트에서 발생되는 TVOCs의 방출강도 특성 연구)

  • Kim Shin Do;Kim Jeong Ho;Park Jin Soo;Lee Jeong Joo
    • Journal of Environmental Health Sciences
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    • v.30 no.5 s.81
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    • pp.487-492
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    • 2004
  • Building materials are composed of very complex chemical compounds, and these indoor building materials discharge very much Volatile Organic Compounds(VOCs). We performed the environmental chamber test to investigate the Total VOCs(TVOCs) emission characteristics and emission factors about chemical and natural coating materials. As the result, we concluded that TVOCs emission are high at initial time and decreased in course of time. Natural paint was low emission level for TVOCs than chemical paint by small chamber test. The TVOCs emission factor-time profile showed a good fit with the results from the measured and predicted value.

High Brightness Prism Light-guide Plate for TFT-LCDs Using Optical Simulation and Novel Injection Mold Process (광학시뮬레이션과 새로운 사출성형법을 사용한 TFT-LCD용 고휘도 프리즘 도광판)

  • Han, Jeong-Min;Shon, Jin-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.61 no.2
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    • pp.93-96
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    • 2012
  • We have designed high performance prism light-guide plate (LGP) in 17 inch TFT-LCD. In test result to embody high brightness BLU in case of LGP of base and upper surface with 17 inch, thickness 8mm adding prism construct. Using optical simulation, we forecast the brightness and uniformity in LGP with prism structure. And we adopted novel injection mold method and Nickel stamper to make actual evolution sample. Novel injection mold process has steady heating time zone in heat cycle time of injection mold process. For this novel heat cycle control, we achieved above 90[%] height prism structure as our design. It is superior brightness improvement than previous that of printing form about some 20[%] and in this course to embody actual material it succeeded prism LGP production by 17 inch injection form process.

Long-term Fistula Formation Due to Retained Bullet in Lumbar Spine after Gunshot Injury

  • Jeon, Se-Il;Im, Soo Bin;Jeong, Je Hoon;Cha, Jang Gyu
    • Journal of Trauma and Injury
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    • v.30 no.2
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    • pp.51-54
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    • 2017
  • We here report a case of long-term fistula formation due to bullet retention for 30 years in the lumbar spine after a gunshot injury, and describe its treatment. A 62-year-old male visited our hospital due to pus-like discharge from his left flank. The discharge had been present for 30 years, since his recovery from an abdominal gunshot injury. A spine radiography showed radiopaque material in the body of the third lumbar vertebra. Foreign body was removed using an anterolateral retroperitoneal approach. The postoperative course was uneventful. The patient was discharged 7 days after the operation and was followed-up for 8 months, during which time, the fistula did not reoccur. A bullet retained long term in the vertebral body may cause obstinate osteomyelitis and fistula formation. A fistula caused by a foreign body in the spine can be effectively treated by surgical removal.

Strength Characteristic and Phenomenon of Heated Concrete by High Temperature (고온가열 콘크리트의 강도 특성과 현상)

  • 태순호;이병곤
    • Journal of the Korean Society of Safety
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    • v.12 no.3
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    • pp.132-138
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    • 1997
  • For many years concrete has been the major building material for most construction. It is of primary importance that fire fighters or fire investigators have a full understanding of the properties of concrete so that better control of the fire scene is achieved. This, in turn, not only help to ensure a safer fire-fighting job but also a more successful fire investigation. So far as the fire scene investigation in concerned, knowledge about the thermal behaviour of concrete can help the investigators to determine the highest temperature that a particular spot of a fire scene has ever reached thereby providing data which may be of value in reconstructing the course of the fire.

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CAPACITY ANALYSIS OF THE SILVER OXIDE-ZINC CELL (PHASE 1)

  • 이완구
    • Journal of the Korean Professional Engineers Association
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    • v.14 no.4
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    • pp.15-25
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    • 1981
  • Electrical behaviors of the divalent silver oxide-zinc cell were analyzed for imporving capacity and keeping electrodes from passivation or sharp increases of cell internal resistance in the course of discharge. One of primary factors in relation to lowering performance can be depicted by cell internal resistance increase being created by various routes, first by insufficiency and/or the carbonation of the electrolyte, secondly by barrier blockage, thirdly by electrode passivation which are due to improper material use of wrong processing, and by gassing as fourth cause. The carbonation causes electrobyte to have impedance up as well as poor amalgamation, resulting in vigorous corrosion reaction of copper plated inner top, evolving hydrogen gas. Electrical characteristics of the cell was reviewed to elucidate relationships between the discharge capacity and the cell internal resistance.

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Development of a Multimedia Package on Operation and Maintenance of Air Brake System for Indian Railways - A Case Study

  • Lalla, G.T.;Mehra, Chanchal
    • Journal of Korea Multimedia Society
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    • v.6 no.4
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    • pp.668-675
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    • 2003
  • Now a days many industries and bigger organisation (Indian Railways, Bharat Heavy Electricals Ltd.) are facing difficulties in implementing the new technology because of non-availability of fully trained staff. Also for the employed technical and other staff lot of resistance management has to face to get them trained for adoption of new technology. There are also very less organisations who can design effective training programmes and at the same time develop course material specially multimedia packages and computer base training (CBT) which can satisfy the need of different target groups of industries. Indian Railways was also facing similar situation while implementing the Air Brake System technology In Indian Railways. TTTI Bhopal took that challenge and designed, developed and trained Indian Railways trainer for implementation of the package on different target group. The present paper offers a case study on the same.

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