• 제목/요약/키워드: 열파괴

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Cloning and Expression of the Pasteurella haemolytica A1 leukotoxin Gene in Bacillus subtilis (Bacillus subtilis을 이용한 Pasteurella haemolytica A1 leukotoxin 유전자의 cloning 및 발현)

  • Yoo, Han-sang;Maheswaran, Samuel K.
    • Korean Journal of Veterinary Research
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    • v.36 no.3
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    • pp.665-680
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    • 1996
  • Bovine Pneumonic Pasteurellosis는 수송열(輸送熱)로 일반적으로 알려져 있는 질병으로서, 여러가지 요인의 복합적(複合的)인 작용에 의해 발병하는 것으로 알려져 있으나, Pasteurella haemolytica A1이 가장 주요(主要)한 인자(因子)로 밝혀져 있다. P haemolytica A1은 leukotoxin(LKT), lipopolysaccharide(LPS), capsular polysaccharide 등 여러가지의 병원성인자(病原性因子)을 생성한다. 이들 인자중 LKT가 가장 중요한 병원성인자로 밝혀져 있다. 이에 본 실험은 P haemolytical A1의 LKT 유전자를 Bacillus subtilis에서 발현(發現)시킴으로서 LPS에 오염(汚染)되지 않은 LKT을 대량으로 생산할 목적으로 실시되었다. 실험의 첫 단계(段階)로서 pLKT52 plasmid을 Sau3 A1의 제한효소을 이용하여 부분소화(部分消化)시킨 후 이 부분 소화(消化)된 유전자들로부터 3~5kb 크기의 유전자들을 순수분리하여 pUC18와 결합시킨 후 E coli NM522에 형질전환(形質轉換)시켰다. 이때 형질전환된 균주들은 LKT에 대한 단크론 항체인 MAb601을 이용하여 colony blot 법에 의해서 LKT 유전자 보유 및 발현여부(發現與否)을 조사하였다. 이들 양성 clone들은 제한효소분석(制限酵素分析), 염기서열분석(鹽基序列分析) 및 Western blot 등에 의해서 재확인(再確認)하였다. 총 9개의 양성 clone중 위의 방법에 의해서 한 clone을 선택(選擇)하여 lktCA insert를 재분리하여 shuttle vector에 subcloning 하였다. Subcloning된 LKT 유전자들은 shuttle vector의 종류(種類)(pHPS9, p602/20, pHPS9-Sac)와 각기(各其) 다른 종류(種類)의 B subtilis(spoO12A, BR121, WB3O, Raj1105) 숙주내(宿主內)에서 발현정도를 Western blot 법에 의해서 비교(比較)하였다. 이때 최적발현조건(最適發現條件)은 p602/20와 pBL1의 dual plasmid system을 이용하여 B subtilis spoO12A에서 2시간동안 IPTG로 발현을 유도(誘導)하는 것이었다. B subtilis에서 발현된 LKT을 visual 법과 neutral red uptake 법을 이용하여 소 폐포(肺胞) 대식구(大食求)에 대한 biological activity를 확인하였다. 발현된 LKT에 대한 LPS 오염은 LKT을 SDS-PAGE 후 silver stain에 의해서 확인하였다. 본 실험을 통해서 볼 때에 lktCA 유전자를 보유(保有)하고 있는 p602/20는 B subtilis에서 매우 불안정(不安定)하였고, 발현된 LKT는 세균자체(細菌自體)에서 생성되는 protease들에 의해서 파괴(破壞)됨으로서 농도(濃度)가 매우 낮았다. 이러한 문제점들은 다음 단계(段階)의 실험에서 해결되어야할 문제들이다.

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On the alcoholic fermentation by using the starch saccharified enzyme system (효소제이용(酵素劑利用)에 의(依)한 주정발효(酒精醱酵)에 대(對)하여)

  • Sung, Nack-Kie
    • Applied Biological Chemistry
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    • v.8
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    • pp.45-50
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    • 1967
  • Starch was liquefied by the bacteriological ${\alpha}-amylase$ and saccharified separately by four strains of mold as saccharogenic enzymes, then thise was fermented for research the fermentation rates, the usefulness of application of four strains of mold and the S.P to need in proportion increasing of concentration of mixed-starches for brewing in this experiment. The obtained results were as follows: 1) In the ability of saccharificatien, fermentation and acid resistance, Aspergillus usamii mut shirousamii, which were used to produce the koji, were excellent, however, Rhizopus delemar had heavy pollution in a lot of production of koji, were-as its qualities as enzyme was good. 2) The necessary S.P in proportion to the concentration of mixed-starch for brewing was found in this experiment in which was fermented in the various concentration of the adding S.P and the mixed-starches for brewing. 3) In the experiment of almost manufacture scale, the S.P needed essentially in the saccharogenic formentation was found and the usefulness of the necessary S.P was observed, and in fact in the manufacture scale it was safer to add the S.P more than 1.2% because it must be considered that the ability of enzymes is reduced by heat or acid. 4) The period of fermentation was shorten because the conditions for yeast propagation were excellent as a results of starches being liquefied by bacteriological amylase, and saccharified by molds as saccharogenic enzymes.

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A Study on the High Frequency Ultrasonic Attenuation Characterization in Artificially Aging Degraded 2.25Cr-1Mo Steel (2.25Cr-1Mo 강 인공 열화재의 고주파수 초음파 감쇠특성에 관한 연구)

  • Park, Ik-Keun;Park, Un-Su;Kim, Chung-Seok;Kim, Hyun-Mook;Kwun, Sook-In;Byeon, Jai-Won
    • Journal of the Korean Society for Nondestructive Testing
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    • v.21 no.4
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    • pp.439-445
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    • 2001
  • The destructive method is reliable and widely used lot the estimation of material degradation but, it have time-consuming and a great difficulty in preparing specimens from in-service industrial facilities. Therefore, the estimation of degraded structural materials used at high temperature by nondestructive evaluation such as electric resistance method, replica method, Barkhausen noise method, electro-chemical method and ultrasonic method are strongly desired. Ultrasonic nondestructive evaluation technique has been reported good to attain efficiency of measurement, high sensitivity of measurement, and rapidity and reliability of result interpretation. In this study, it was verified experimentally the feasibility of the evaluation of degraded 2.25Cr-1Mo steel specimens which were prepared by the isothermal aging heat treatment at $630^{\circ}C$ by high frequency longitudinal wave method investigating the change of attenuation coefficient by FFT analysis and wavelet transform. Because of carbide precipitation increase and spheroidization near grain boundary of microstructure to aging degradation, attenuation coefficient had a tendency to increase as degradation proceeded. It was identified possibly to evaluate degradation using the characteristics of high-frequency ultrasonics. Frequency dependence of ultrasonic attenuation coefficient to aging degradation appeared large, which made sure that attenuation coefficient is an important parameter for evaluation of aging degradation.

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Ultrastructures of Zinc-containing Mast Cells Found in the Rat Hindpaw after an Inflammatory Stimuli: Zinc Selenium Autometallography (랫드 발바닥 염증부위에서 관찰된 zinc함유 비만세포의 미세구조: 조직화학적 염색을 중심으로)

  • Lee, Bo-Ye;Kim, Yi-Suk;Lee, Boeb-Y.;Lee, Hyun-Sook;Tak, Gye-Rae;Lee, Young-Il;Lee, Jeoug-Yeol;Jo, Seung-Mook
    • Applied Microscopy
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    • v.36 no.4
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    • pp.271-277
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    • 2006
  • Mast cells (MCs) are granulated cells that play a pivotal role in allergic reaction and inflammation. The granules of mast cells are known to be rich in zinc (Zn). Male Sprague-Dawley rats were used. We injected $200{\mu}L$ of complete Freund's adjuvant (CFA) subcutaneously in the dorsal aspect of one hindpaw Finally, zinc selenium autometallography(AMG) was done by Danscher's method. The present study showed the ultrastructures of zinc-containing mast cells found in inflammatory area following an complete freund's adjuvant (CFA) inoculation into the rat hindpaw. At light microscopic level, mast cells were round or oval, at average $12{\mu}m$ in diameter, with many filopodia extending from the cell surface. Because the rather small and spherical nucleus was centrally placed; it was frequently obscured by the cytoplasmic granules, it sometimes could not be seen. Mast cells were distributed chiefly in the vicinity of small blood vessels. In most preparation many mast cells were ruptured and their granules escaped into the surrounding tissue. In electron micrographs, The secretory granules were at average $0.5{\mu}m$ in diameter and were limited by a membrane. The cell surface contained numerous microvilli and folds. Their interior was heterogenous in appearance. The nucleus was surrounded by large numbers of prominent vesicels and a well developed Golgi apparatus, but scant endoplasmic reticulum.

Fire Resistance Performance of High Strength Concrete with 4 Deformation Factors (4변형 인자에 의한 고강도콘크리트의 내화성능 평가)

  • Lee, Tae Gyu
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.5
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    • pp.112-120
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    • 2012
  • A numerical model considering the internal vaporization and the creep effect, in the form of a analytical program, for tracing the behavior of high strength concrete(HSC) members exposed to fire is presented. The two stages, i.e., spalling procedure and fire resistance time, associated with the thermal, moisture flow, creep and structural analysis, for the prediction of fire resistance behavior are explained. The use of the analytical program for tracing the response of HSC member from the initial pre-loading stage to collapse, due to fire, is demonstrated. Moisture evaporates, when concrete is exposed to fire, not only at concrete surface but also at inside the concrete to adjust the equilibrium and transfer properties of moisture. Finite element method is employed to facilitate the moisture diffusion analysis for any position of member, so that the prediction method of the moisture distribution inside the concrete members at fire is developed. The validity of the numerical model used in this program is established by comparing the predictions from this program with results from others fire resistance tests. The analytical program can be used to predict the fire resistance of HSC members for any value of the significant parameters, such as load, sectional dimensions, member length, and concrete strength.

Long-Term Compressive Strength and Durability Properties of "CSG" Materials by Freezing-Thawing Test (동결융해시험에 의한 "CSG" 재료의 장기강도 및 내구 특성)

  • Jin, Guangri;Kim, Kiyoung;Moon, Hongduk;Quan, Hechun
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.12
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    • pp.35-43
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    • 2016
  • With the development of construction technology, constructions of dam and levee (dike) as well as the environmental problems are becoming issues. Recently, many countries have tried to develop and used CSG (Cemented Sand and Gravel), which needs fewer requirements than others in aggregates, constructability and ground condition during the dam construction. Mixing up with small amount of cement, CSG is able to increase the strength and proceed accelerated construction without artificial gradation adjustment of riverbed aggregate and crushed rock on construction site. Thus, CSG can minimize environmental damage resulted from quarries mining and reduce cost of construction. Unlike heat of hydration condition that regular concrete usually met, CSG exposes to repeated dry-wet and freezing and thawing environment. Thus, consider the importance of structure of dam or levee, intensive study on the durability of CSG is needed. In this study, freezing and thawing experiment was carried out to evaluate the durability of CSG. In results, the durability factor of CSG is 30~40 or >40 when the amount of cement is $0.4{\sim}0.6kN/m^3$ or $0.8{\sim}1.0kN/m^3$, respectively. The unconfined compressive strength is reduced to 30~50% or 40~70% when the amount of cement is $0.4{\sim}0.6kN/m^3$ or $0.8{\sim}1.0kN/m^3$, respectively. Taken together, the strength and durability of CSG is reliable when the amount of cement is over $0.8kN/m^3$.

Expression of HSP70 Immunoreactivity in EPO Treated Rat Kidney (콩팥에서 Erythropoietin 투여로 인한 HSP70의 발현 변화)

  • Jung, Ju-Young;Kim, Jin
    • Applied Microscopy
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    • v.37 no.3
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    • pp.167-174
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    • 2007
  • Heat shock protein (HSP) 70 functions as a molecular chaperon and reduces stress-induced denaturation and aggregation of intracellular proteins. Erythropoietin (EPO) plays an important role during acute renal failure repair process by rapidly correcting anemia and enhancing renal tubular regeneration. The purpose of this study was to examine the effect of EPO treatment on renal HSP70 expression. Male Sprague-Dawley rats were injected rHUEPO. Kidney were preserved by in vivo perfusion with paraformaldehyde-lysine-periodate (PLP) and processed for immunohistochemistry and electron microscopy. In control kidney, HSP70 was expressed in the cortex, outer medulla and inner medulla. Especially, HSP immunoreactiviy was mainly founded in descending thin limb of outer medulla and inner medullary collecting duct. In EPO treated kidney, HSP70 expression markedly increased in the descending thin limb of outer medulla and newly detected in cortical collecting duct. Electron microscopy showed the presence of HSP immunoreactivity on the intracelluar vesicles and Golgi complex of descending thin limb and cortical collecting duct. These findings suggest that EPO treatment leads to new production of HSP70 in renal tubular cells, and induction of HSP70 by rHuEPO is causally related to protective function.

Sensory Characteristics of Purple-fleshed Sweet Potato Jam with Varying Sugar Contents (자색고구마 잼의 설탕 함량에 따른 관능적 특성)

  • Kim, Ye Rim;Shim, Ki Yeon;Yoon, Ji Hyun;Choi, Soo Yeon;Koh, Eunmi
    • Journal of the East Asian Society of Dietary Life
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    • v.25 no.4
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    • pp.660-666
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    • 2015
  • Natural food colorant are widely used to satisfy consumer preferences. Anthocyanins are red, blue and purple natural pigments. Purple-fleshed sweet potato (PSP) contains large quantities of anthocyanins. The aims of this work were i) to investigate the influence of sugars on the purple color of PSP jam and ii) to optimize the ratio of ingredients for sensory characteristics of PSP jam. Korean PSP variety "Sinjami" was used for the preparation of jam. The jams were prepared with various sugar contents (0, 20, 30, 40 and 50% total weight) consisting of steamed purple-fleshed sweet potato, water, lemon juice and apple juice. With increasing sugar contents, lightness (L) and redness (a) of PSP jams decreased while yellowness (b) increased, indicating that anthocyanins were degraded and/or brown pigments were formed due to high sugar content under heat treatment. Hardness, springiness, chewiness and cohesiveness showed significant differences among PSP jams with various sugar contents. In sensory evaluation, addition of sugar significantly increased scores for color and texture as compared to control samples. The color, texture and preference results indicate an optimal sugar content of 40% total ingredient weight for PSP jam.

Chemical Properties of Barley Leaf Using Different Drying Methods (건조방법을 달리한 보리 잎의 이화학적 특성)

  • Park, Soo-Jin;Joung, Yong-Myeon;Choi, Mi-Kyeong;Kim, Yang-Kil;Kim, Jung-Gon;Kim, Kyong-Ho;Kang, Myung-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.1
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    • pp.60-65
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    • 2008
  • Chemical properties of barley leaf were investigated using different drying methods. Moisture contents of barley leaf were 75.22%, 7.54%, 2.57%, 6.74% and 8.91% for samples dried using raw, hot-air dryer, freeze dryer, shade dryer, vacuum freeze dryer and microwave dryer, respectively. Mineral contents were high Ca, Mg, Na, P, and K in barley leaf regardless of drying methods. Organic acid contents were oxalic acid, acetic acid, citric acid and fumaric acid with no differences between drying methods. Contents of vitamin C were 142.56 mg%, 629.23 mg%, 598.48 mg%, 657.62 mg% and 724.34 mg% for samples using raw, hot-air dryer, freeze dryer, shade dryer, vacuum freeze dryer and microwave dryer, respectively. Chlorophyll contents of barley leaf dried by hot-air dryer and shade dryer were higher than in that of freeze dryer and microwaves dryer. b-values were lower in freeze dryer than in that of other dried methods.

A CASE REPORT OF DENTINOGENESIS IMPERFECTA (상아질 형성부전증에 대한 증례 보고)

  • Jun, Eun-Min;Kim, Eun-Jung;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.2
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    • pp.323-328
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    • 2006
  • Dentinogenesis imperfecta is an inheritable disease of dentinal defect, generally is inherited as a single autosomal dominant trait. It has a prevalence of 1 in 8000 with the trait, and no significant difference between male and female, with involvement of the primary and permanent teeth. Shields proposed three types of Dentinogenesis imperfecta. Affected teeth have various discoloration, separation of enamel rapid destruction of underlying dentin, and severe attrition. Radiographically, the teeth have cervical constriction, bulbous crown, thin root, obliteration of the root canals and pulp chambers, and periapical lesions in a sound tooth. The objective of treatment is rehabilitation of the esthetics, the masticatory function, and the vertical dimension of occlusion. In these cases, two pediatric patients reported to the Kyungpook University Pediatric clinic, with a chief complaint of discolored teeth and severe attrition. As a result of clinical and radiographic exam, it was diagnosed as Dentinogenesis imperfecta. The posterior teeth were restored with Stainless Steel Crown, and the anterior teeth were restored with composite resin veneering.

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