• Journal of Applied Biological Chemistry
• /
• 제53권1호
• /
• pp.1-7
• /
• 2010

xylA 프로모터는 대장균의 xylose 대사에 관여하는 xylose 오페론 상의 중요한 프로모터이다. 이 프로모터는 xylose에 의해 강하게 조절을 받는다고 알려져 있다. 이러한 특징은 새로운 발현 백터를 구축하는데 충분한 조건을 갖추고 있다고 생각된다. 본 연구에서는 이러한 xylose에 의해 유도 되는 발현벡터를 구축하기 위하여 600 bp의 xylA 프로모터를 증폭하여 pUC18의 AatII와 HindIII 사이에 삽입하여 pXA600을 구축하였다. 또한 조절단백질인 XylR의 영향을 조사하기 위하여 xylR 유전자를 삽입하여 pXAR600을 구축하였다. 발현의 강도를 측정하기 위하여 3,048 bp의 lacZ유전자를 xylA 프로모터의 하류에 연결하여 pXA600-lacZ와 pXAR600-lacZ를 구축하고 대장균 JM109에 형질전환시켰다. 구축된 pXA600-lacZ와 pXAR600-lacZ는 LB 배지에서 배양하였을 때 xylose 유도하에서 각각 1,641 unit와 2,304 unit의 $\beta$-galactosidase 활성을 보였으며, DM 배지상에서 배양했을 때 xylose 유도 시 각각 6,282 unit와 9,320 unit의 $\beta$-galactosidase 활성을 보였다. 또한 왜래 유전자의 발현 가능성을 확인하기 위하여 S. thermocyaneoviolaceus의 내열성 xylanase를 코딩하는 xynA 유전자를 실제로 구축된 pXA600과 pXAR600에서 발현을 확인하여 pXA600 및 pXAR600이 새로운 xylose 유도성 발현벡터로서의 사용 가능성을 확인하였다.

• Tribology and Lubricants
• /
• 제19권1호
• /
• pp.31-35
• /
• 2003

This paper reports the studies on the wear-corrosion behavior of ductile cast iron in the various pH environments. In the variety of pH solutions, corrosion and wear-corrosion loss of GCD 600 were investigated. Also, the anodic polarization test of GCD 600 using potentiostat/galvanostat was carried out. And rubbed surface of GCD 60 using scanning electron micrographs after immersion and wear-corrosion test was examined in the environment of various pH values. The main results are as following In alkali zone, the wear-corrosion loss of GCD 600 increases, but corrosion loss decreases. The unevenness and crack of wear-corrosion surface in neutral zone becomes duller than that in alkali zone. As the corrosive environment is acidified, wear-corrosion behavior of GCD 600 with passing immersion time becomes sensitive.

• 사상체질의학회지
• /
• 제9권2호
• /
• pp.227-243
• /
• 1997

The experimental study used in this paper was done to examine the clinical effects of Taeumchowetang for the gastric ulcer and the function of gastrointestinal tract using rats and mice which were administered orally the water extraction from Taeumchowetang. Then, the counter-action of the water extraction on the isolated ileum and gastric fundus, the inhibitory effects of pylorus-ligated ulcer and indomethacin-induced ulcer, the associations with gastric juice secretion, total acidity, pepsin output, the transportability in the small and large intestine, were studied with administering acetylcholine chloride and barium chloride. In addition, it was investigated whether the central nervous system related to pain control and sleeping time was influenced by Taeumchowetang. The following results have been obtained; 1. As resulting from injection of acetylcholine chloride and barium chloride into the isolated ileum of rats and mice, Taeumchowetang led to have an inhibitory effect on the muscle contraction of the ileum. Then, acetylcholine chloride was measured as lower effect than barium chloride 2. For the inhibitory effect on contraction for the gastric fundus strip in rats by either acetylcholine chloride or barium chloride, the one showed low inhibitory effect, on the other hand the other showed density-dependent effect. 3. The water extraction was given on the pylorus ligated ulcer with using two different administration groups of 1,300mg/kg and 2,600mg/kg, each result was measured as 22.9% and 36.5% for an ulcerous inhibitory effect (p<0.05). 4. According to the two administration groups, the preventive effect was tabulated 18.1% and 29.3% for indomethacin-induced ulcer (p<0.05, P<0.01). 5. For associations with gastric juice secretion, total acidity, pepsin output in the administration group 2,600mg/kg, Taeumchowetang was recognized as having an inhibitory effects related to suppressive actions involving gastric juice secretion(p<0.05), and free acidity(p<0.01), but there was no significant association with total acidity and pepsin output. 6. To know the transportability in the intestine, BaSO4 solution was used. The transportability of the small intestine in the administration group 2,600mg/kg was 22.2% which was statistically significant compared with the large intestine's transportability(P<0.01). 7. In the administration group 1,300mg/kg and 2,600mg/kg, analgesic effect with against acetic acid was measured as being 16.8% and 24.4% which was shown as statistically siginificant(p<0.01). 8. No statistically significant association between Taeumchowetang and sleeping time was found in both 1,300mg/kg and 2,600mg/kg by administering phenobarbital-Na. According to the results of this study, Taeumchowetang has agreed with the effects of literature review. Further more in this study, Taeumchowetang also has preventive effects on pylorus-ligated ulcer. Hence, Teaumchowetang can be significant effect such as both anti ulcer agent and increasing gastric activity for the patients who suffer from gastric ulcer.

• Asian-Australasian Journal of Animal Sciences
• /
• 제26권7호
• /
• pp.945-951
• /
• 2013

In vitro studies were undertaken to develop an appropriate fibrolytic enzymes cocktail comprising of cellulase, xylanase and ${\beta}$-D-glucanase for maize stover with an aim to increase its nutrient utilization in sheep. Cellulase and xylanase added individually to ground maize stover at an increasing dose rates (0, 100, 200, 400, 800, 1,600, 3,200, 6,400, 12,800, 25,600, 32,000, 38,400, and 44,800 IU/g DM), increased (p<0.01) the in vitro dry matter digestibility and in vitro sugar release. The doses selected for studying the combination effect of enzymes were 6,400 to 32,000 IU/g of cellulase and 12,800 to 44,800 IU/g of xylanase. At cellulase concentration of 6,400 IU/g, IVDMD % was higher (p<0.01) at higher xylanase doses (25,600 to 44,800 IU/g). While at cellulase doses (12,800 to 32,000 IU/g), IVDMD % was higher at lower xylanase doses (12,800 and 25,600 IU/g) compared to higher xylanase doses (32,000 to 44,800 IU/g). At cellulase concentration of the 6,400 to 32,000 IU/g, the amount of sugar released increased (p<0.01) with increasing levels of xylanase concentrations except for the concentration of 44,800 IU/g. No effect of ${\beta}$-D-glucanase (100 to 300 IU/g) was observed at lower cellulase-xylanase dose (cellulase-xylanase 12,800 to 12,800 IU/g). Based on the IVDMD, the enzyme combination cellulase-xylanase 12,800 to 12,800 IU/g was selected to study its effect on feed intake and rumen fermentation pattern, conducted on 12 rams (6 to 8 months; $20.34{\pm}2.369$ kg body weight) fed 50% maize stover based TMR. The total volatile fatty acids (p<0.01) and ammonia-N concentration was higher in enzyme supplemented group, while no effect was observed on dry matter intake, ruminal pH and total nitrogen concentration.

• 한국가금학회:학술대회논문집
• /
• 한국가금학회 2006년도 제23차 정기총회 및 학술발표회
• /
• pp.17-27
• /
• 2006

The effects of dietary betaine on performance, blood compositions, hepatic amino acid concentrations and hormonal secretions were examined in laying hens. Egg production was significantly higher in birds fed the 16.5 % protein diet compared to those fed 14.5 % protein diet(p<0.05), whereas dietary supplementation of betaine did not show any significant effect. The high level of protein and betaine supplementation significantly improved egg weight, egg mass and feed conversion(p<0.05), while eggshell breaking strength, eggshell thickness and Haugh unit were not influenced by betaine and dietary protein levels. Supplemental betaine did not affect serum total protein, albumin and BUN concentration. However, uric acid concentration significantly increased in 600 ppm betaine-fed groups(p<0.05). Concentrations of most hepatic amino acid were influenced by increased protein feeding and dietary betaine supplementation. Hormone studies recorded significantly higher serum and hepatocyte IGF-I concentration in 600 and 1,200 ppm betaine treatments(p<0.05) compared to those of control group. IGF-I mRNA gene expression of hepatocytes revealed statistically correlated increase in 600 and 1,200 ppm betaine-fed groups compared to the controls(p<0.05). Serum IGFBP-3 concentration was significantly elevated in 600 ppm betaine treatments. However, the secretion of IGFBP-1 in hepatocyte of laying hens fed with 600 and 1,200 ppm of betaine showed a significant decrease compared to the control group(p<0.05). Results of these study show that dietary betaine supplementation affects protein and hormone metabolism in laying hens.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권8호
• /
• pp.1168-1174
• /
• 2017

Objective: The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm $KNO_3$) on the volatile compounds and some other properties of pastırma. Methods: Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS) as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results: Nitrate level had a significant effect on pH value (p<0.05) and a very significant effect on TBARS value (p<0.01). No significant differences were determined in terms of $a_w$ value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05) or a very significant (p<0.01) effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05). While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion: The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

• 한국세라믹학회지
• /
• 제33권4호
• /
• pp.432-440
• /
• 1996

본 연구는 졸-겔법을 이용하여 알칼리 조건인 pH 10에서 제조한 ZrO2의 하소온도에 따른 분말특성과 코발트 흡착량에 미치는 하소온도의 영향에 대하여 검토하였다. 졸-겔법을 이용하여 ZrO2 분말을 제조하고, 600, 800, 1000, 1200, 140$0^{\circ}C$로 하소한 후, X-선 회절법, SEM, BET 방법, Fourier transform 적외선(FT-IR), 열중량 및 열시차분석법(TG-DTA)등을 이용하여 특성을 분석하였다. 알칼리조건인 pH 10에서 제조한 ZrO2는 하소온도가 $600^{\circ}C$일때 고온수에서 코발트 흡착량이 가장 우수하였으며, 이때 $600^{\circ}C$로 하소한 ZrO2의 비표면적은 24.03m2/g이였으며 25$0^{\circ}C$의 고온수에서 코발트 흡착량은 0.16m-eq/g이였다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 1995년도 제9회 학술발표회 논문개요집
• /
• pp.149-149
• /
• 1995

• 방사성폐기물학회지
• /
• 제4권2호
• /
• pp.103-116
• /
• 2006

본 논문은 국내 PWR 발전소에서 S/G tube 재질로 사용되고 있는 Inconel 600 및 690에 대한 부식 실험을 수행함으로써 작업자들의 주요 피폭원인 $^{58}Co,\;^{60}Co,\;^{51}Cr,\;^{54}Mn,\;^{59}Fe$의 생성량을 예측하고자 하였다. 이를 위해 Inconel 600 및 690 재질로 총 12개의 시편을 제작하여 실제 발전소의 운전조건과 유사하거나 가혹한 조건에서 전면 부식실험을 pH별로 20일씩 총 60일간 수행하였고, 실험 결과를 정량적으로 분석하기 위해 GDS(Glow Discharge Spectrometer) 장비를 사용하였다. GDS 장비를 이용하여 정량적으로 분석한 결과 pH 7 및 9에서는 Inconel 600이 Inconel 690에 비해 부식이 잘 되는 것으로 나타난 반면, pH 4에서는 Inconel 690이 부식이 더 잘 되는 것으로 평가되었다. 이러한 경향을 보이는 것은 과도상태의 영향이 과도하게 반영된 것에 기인한 것으로 비교적 정확한 결론을 도출하기 위해서는 장시간의 부식 실험을 수행함으로써 과도상태에 의한 영향을 최소화해야 할 것으로 판단된다.

• 한국진공학회지
• /
• 제6권4호
• /
• pp.343-347
• /
• 1997

전기적 고립(isolation) 효과를 알아보기 위해 $P^+$-InGaAs층에 oxygen을 이온 주입하 여 annealing 온도에 따른 compensation mechnism을 조사하였다. $500^{\circ}C$이하에서는 전도도 가 손상에 관련된 트랩들에 의해 지배되며 500~$600^{\circ}C$영역에서는 oxygen의 활성화로 acceptor를 compensate시키는 화학적 효과를 나타냈으며 특히 $600^{\circ}C$에서 type conversion(p $\longrightarrow$n-type)이 일어났다. 이는 annealing온도가 증가함에 따라 oxygen의 화학적 작용에 의해 생성된 donor로 작용하는 결함들의 증가에 기인하며, 이때 면 저항의 활성화 에너지는 24.2meV로 shallow donor로 작용하는 In interstitial과 같은 native defect들이 형성되기 때 문이라 생각된다. Type conversion이 일어난 $600^{\circ}C$ 이상의 영역에서는 이온 주입에 의해 형 성된 interstitial Be의 재활성화로 인해 n형 전도도가 감소하는 경향을 보였다.