• 한국연초학회지
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• 제15권1호
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• pp.26-33
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• 1993

Effect of an avirulent bacteriocin-producing strain(ABPS) of Pseudomonas solanacearum adapted to low temperature on the control of tobacco bacterial wilt was examined under the natural field conditions. The ABPS of p. solanacearum were succeeding-cultured at gradually low temperature, 3$0^{\circ}C$ to 13$^{\circ}C$. The isolates adapted to low temperature grew faster than the wild type either in artificial media or on the tobacco rhizoplane. The control effect of one of the isolates on bacterial wilt was higher than that of the wild type when the bacterial suspension had been poured onto the tobacco rhizosphere soil on 1 day before and 15 days after transplanting to the field. It was suggested that ABPS of p. solanaceamm adapted to the low temperature, might be more effective biological control agent than the wild type.

• 대한조선학회논문집
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• 제53권3호
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• pp.210-216
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• 2016

Direct numerical simulations of a spatially developing turbulent boundary layer on a flat plate have been performed to verify the applicability of OpenFOAM and adapted mesh with prism layers to turbulent numerical simulation with high fidelity as well as provide a guideline on numerical schemes and parameters of OpenFOAM. Reynolds number based on a momentum thickness at inlet and a free-stream velocity was Re_θ=300. Time dependent inflow fields with near-wall turbulent structures were generated by a method of Lund et al. (1998), which was to extract instantaneous velocity fields from an auxiliary simulation with rescaled and recycled velocities at inlet. To ascertain the statistical characteristics of turbulent boundary layer, the mean profiles of streamwise velocity and turbulent intensities obtained from structured and adapted meshes were compared with the previous data.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.374-377
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• 2003

본 연구에서 hybridoma 세포는 $K^+$농도를 80 mM까지 높인 배지에 적응시켰다. $K^+$ 80 mM에 적응된 세포는 높은 삼투압과 낮은 pH에서 내성을 가졌다. 적응되지 않은 세포와 $K^+$ 80 mM에 적응된 세포는 Erlenmeyer flask에서 강화 배지로 회분 식으로 배양되었다. 배지의 삼투압이 450 $mOsm/kgH_2O,$일 때 적응되지 않은 세포의 최대 세포 농도가 $4.8{\times}10^5$ cells/ml로 낮은 성장을 보였고, 적응된 세포는 $1.1{\times}10^6$ cells/ml까지 성장하였다. 또한 배지의 초기 pH가 7.0일 때 적응되지 않은 세포는 $5.3{\times}10^5$ cells/ml인 반면, $K^+$ 80 mM에 적응된 세포 농도는 $7.8{\times}10^5$ cells/ml였다. 따라서, 동물세포의 높은 $K^+$농도에의 적응은 세포배양의 한계조건에서 적응되지 않은 세포가 받는 성장 저해를 줄여줄 것이다.

• 한국응용곤충학회지
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• 제34권4호
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• pp.334-343
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• 1995

명상태와 암상태에서 벼멸구의 겹눈의 미세구조가 변화하는 것을 관찰하였다. 벼멸구의 겹눈을 암조건 혹은 광조건 하에서 최고 72시간 까지 유지하였을 경우에 비슷한 수준에서 겹눈을 절단하여 해부 현미경으로 관찰한 결고, 구조적인 면에서 서로 다른 모양을 관찰하였다. 한편, 전자현미경을 이용하여 암조건과 광조건 하에서의 겹눈의 미세구조를 비교한 결과, 단애층(palisade layer)의 넓이는 광조건하에서 암조건에서 보다 더 좁은 것을 알 수 있었다. 색소체는 암적응 상태의 눈에서는 단애층 주위에 원을 형성하고 있었지만, 감간채 주위에 밀집되어 있지는 않았다. 암적용과 광적용 상태의 눈에 있는 망막세포 내에서의 미세융모 지름은 차이가 없었으며, 수정체와 감간체의 접합 부위에 있는 색소체의 이동은 감간체의 위부분에 있은 수정체의 끝부분에서 변화가 있음을 관찰 할 수 있었다.

• 한국어류학회지
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• 제23권2호
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• pp.145-149
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• 2011

인위적 수온변화에 의한 미꾸라지 피부의 점액세포 반응을 확인하기 위해 고온($32^{\circ}C$)과 저온($4^{\circ}C$)에 적응시킨 실험군의 표피조직을 실온($18^{\circ}C$)의 대조군 집단과 비교 분석하였다. 그 결과, 고온적응 설험군에서는 대조군과 유의한 차이를 보이지 않았으나, 저온적응 실험군에서는 등, 체측, 후두부의 점액세포 수와 크기가 현저하게 증가하는 경향을 보였다(P<0.01). 또한 저온적응 실험군의 수온을 증가시켜 상온에서 재 적응시킨 결과에서도 피부 정액세포의 수와 크기가 현저히 감소하는 경향을 보였다(P<0.01). 따라서 미꾸라지 피부의 점액세포가 저온에 매우 민감하게 반응하는 양상은 어류의 조직학적 환경지표로서 유용할 것으로 여겨진다.

• Animal Bioscience
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• 제34권1호
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• pp.74-84
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• 2021

Objective: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. Methods: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. Results: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. Conclusion: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

• Journal of applied mathematics & informatics
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• 제24권1_2호
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• pp.95-104
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• 2007

We study stationary subdivision schemes based on radial basis function interpolation. Each scheme has a tension parameter, say ${\lambda}$, which actually belongs to the radial basis function. In particular, adapted subdivision rules on bounded intervals are developed.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.52.2-52.2
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• 2007

See Full Text

• 한국임상수의학회지
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• 제15권1호
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• pp.62-74
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• 1998

In feedlot cattle the abrupt change of diet from roughage to a large quantity of grain for the purpose to improve production often results in increased occurrence of rumen acidosis or acute carbohydrate encouragement enterotoxemia, bloats diarrhea liver abscess and laminitis or robot disease. The common management practice to control these problem is to increase the amount of concentrates in the diet in a stepwise manner until the animals are adapted to a high-grain ration. However this practice requires at least about 3 weeks adaptation period and specially prepared adaptation rations which contain various amount of concentrates. Present experiment was undertaken in order to findout the more simple and rapid adaptation method of cattle to a high grain ration. Nineteen Korean calves aging from four to six month were fed artifical hay (Youngchoun Chuk-Hyup, Korea) which contains 10% of concentrates or alfalfa and rye grass hays for two months and randomly alloted to three experimental groups and two control groups. The experimental group-1 was inoculated by stomach tube for two days with li500 ml/day of ruminal fluid fished from Korean beef cattle that had been previously adapted to a high-energy ration. The experimental group-2 was inoculated by trocalization for two days with the same ruminal fluid. The experimental group-3 was inoculated by trocalization with 1,500 ml/day of bacterial culture which contained 2$\times $10$^{9}$/m1 of Gram-negative bacteria derived from adapted luminal fluid. The two control groups were treated with normal saline solution by the same methods. All animals were fed high-energy ration that contained 80% of grain ad libitum for 30-74 days beginning on the third of the treatment. The effect of the inoculation on the adaptation was observed clinicopathologically with the following results; All of the experimental calves inoculated with the ruminal fluid or Gram-negative bacterial culture derived from adapted cattle did not show any signs of rumen acidosis or other related diseases, while most of the control calves did show diarrhea and bloat and a calf laminitis. The average daily weight gain and feed efficiency of experimental calves were slightly improved compared with control calves. Following the feeding of high-grain rational the pH of the ruminal fluid was lowered in both the experimental and control groups. However severe acidosis with the pH of below 5.0 was observed in only a control group-2. The protozoal number in ruminal fluid was markedly decreased during the high-grain feeding in both the experimental and control calves. However the decrease was mere severe in control calves compared with the experimental calves. The activation of the protozoa were completely disappeared within nine hours at the refrigerator temperature (4"C). No significant differences in heamatological and blood chemical values between the experimental and control calves were recognized. However in one control calf which showed clinically laminitis marked elevations of serum glutamic oxaloacetate transaminase and lactic dehydrogenase activities and a decrease of serum glucose level were observed. From these results it would be concluded the intraruminal transplantation of unadapted calves with the adapted ruminal fluid from cattle previously adapted to a high-energy ration prevents disease problem associated with high-grain feeding and improve weight gain and feed efficiency.ency.

• Journal of Microbiology and Biotechnology
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• 제26권7호
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• pp.1259-1266
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• 2016

Bioethanol was produced from Kappaphycus alvarezii seaweed biomass using separate hydrolysis and fermentation (SHF). Pretreatment was evaluated for 60 min at 121℃ using 12% (w/v) biomass slurry with 364 mM H₂SO₄. Enzymatic saccharification was then carried out at 45℃ for 48 h using Celluclast 1.5 L. Ethanol fermentation with 12% (w/v) K. alvarezii hydrolyzate was performed using the yeasts Saccharomyces cerevisiae KCTC1126, Kluyveromyces marxianus KCTC7150, and Candida lusitaniae ATCC42720 with or without prior adaptation to high concentrations of galactose. When non-adapted S. cerevisiae, K. marxianus, and C. lusitaniae were used, 11.5 g/l, 6.7 g/l, and 6.0 g/l of ethanol were produced, respectively. When adapted S. cerevisiae, K. marxianus, and C. lusitaniae were used, 15.8 g/l, 11.6 g/l, and 13.4 g/l of ethanol were obtained, respectively. The highest ethanol concentration was 15.8 g/l, with Y_EtOH = 0.43 and Y_T% = 84.3%, which was obtained using adapted S. cerevisiae.