• Applied Biological Chemistry
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• v.17 no.1
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• pp.49-53
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• 1974

Mohan's aniline procedure for the quantitative determination of niacin in feed additives containing various vitamines and minerals was compared with microbiological procedure utilizing growth rate of Lactobacillus arabinosus 17-5. Microbioassay was more sensitive than chemical procedure to the detection of standard niacin and was applicable to the determination of minute amounts of niacin. while both microbioassay and chemical proce dure were discovered to be unsatisfactory by the recovery test for the determination of niacin in feed additives containing much interfering substances. But the possibility of the determination of niacin in feed additives on chemical prccedure together with microbioassay was proved.

• Korean Management Science Review
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• v.28 no.1
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• pp.25-42
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• 2011

The mobile industry is the key foundation of digital convergence, and its constant growth is expected. Among mobile industries, new products leading the development of devices are the Emerging Device. This study is conducted to find out factors making differentiated by comparing the structural equation model(SEM) of the Tablet PC and the e-Book Reader. The main findings are as follows. First, the application of TAM to the Emerging Device shows that fitness of the model is generally high but the effect of Perceived Ease of Use has not been verified or found insignificant. Second, the acceptance model of the Tablet PC and the e-Book Reader has found that playfulness stimulates acceptance intentions. Third, the cost level of the Emerging Device acceptance model is not a factor stimulating consumers' acceptance intentions. Fourth, product attributes of the Tablet PC and the e-Book Reader to differentiate themselves from the other device are Functionality and Playfulness respectively.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.275-279
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• 2001

There are two kinds of the design criteria of piping system in petrochemical plant design. The first is on static state evaluation by thermal growth and the other is on dynamic evaluation by piping vibration. In the static design evaluation, the ASME B31.3 code defines 7000 cycles of fatigue life in operating the piping system with design condition. However, the dynamic design evaluation in comparative with small displacements of high frequencies to static condition has not established clearly the method, yet. So, this study purposes to present the trial of a proposal of dynamic design criterion on the basis of static design method.

• Korean Journal of Pharmacognosy
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• v.19 no.2
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• pp.120-126
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• 1988

HPLC analysis of three Prunus species, Armeniacae Semen. Persicae Semen, and Mume Semen, showed that 24. 06 mg/g, 5. 79 mg/g and 3/ 10 mg/g of amygdalin in the MeOH extract and 3. 59 mg/g, 5. 41 mg/g and 13. 48 mg/g of benzaldehyde in the MeOH extract hydrolyzed with ${\beta}-glucosidase$ were contained respectively. The MeOH extract of Mume Semen showed strong antibacterial activities against two species of bacteria (E. coli and B. subtilis) while that of Armeniacae Semen showed mild, and that of Persicae Semen showed no effect. Against A. niger, a strong antifungal activity was observed with Armeniacae Semen and only mild activities with Persicae Semen and Mume Semen. None oh the three inhibited the growth of S. cervisiae. The above results may possibly be suggestive of the correlationships between the contents of amygdalin and benzaldehyde in the test extracts with the antimicrobial potencies.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.227-230
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• 2005

The surgical treatment of craniofacial disorders, using metallic internal osteofixation system has inspired an evolution with advanced operative technique and fixation devices over past two decades. As any other surgical procedures, this procedure also associates problems such as infection, palpability, loosening, and restrict craniofacial skeleton growth, which lead to undue secondary operations for removal. These problems are improved by using bioabsorbable osteofixation system. We compared the patient's subjective symptoms using bioaborbable system versus metallic osteofixation system in zygomatic bone fracture. we should take the individual steps (postoperative 2 weeks, and 1 year) in treating fractured zygoma. From August, 2001 to August, 2003, we used bioabsorbable osteofixation system in 28 patients in zygomatic fracture ($Biosorb^{TM}FX^{(R)}$) and compared 23 patients who were treated with metallic osteofixation system. There was no significant difference in the both groups in subjective symptoms and postoperative result.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.506-508
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• 1986

Metabolic activity of inorganic nitrogenous compounds affects not only microbial growth but also metabolite production in fermentation technology. We have worked on the enzymes participating in ammonia assimulation of some fermentation bacteria. This paper summarizes the results on glutamine synthetase and its application in practical field. Glutamine synthetase (L-glutamate:ammonia ligase, EC. 6.3.1.2) catalyzes the formation of glutamine from glutamate and ammonia at the expense of cleavage of ATP and inorganic phosphate. The enzyme plays a dual role in nitrogen metabolism in bacteria; it is a key enzyme not only in the biosynthesis of various compounds through glutamine but also in the regulation of synthesis of some enzymes involved in the metabolism of nitrogenous compounds. The detailed works with the Eschericia coli and other enterobacterial enzymes revealed that glutamine synthetase is controlled by the following complex of mechanisms: (a) feedback inhibition by end products, (b) repression and derepression of enzyme synthesis, (c) modulation of enzyme activity in response to divalent cation and (d) covalent modification of enzyme protein by adenylylation and its cascade control. Comparative studies have also been made on the enzymes from other organisms.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1977-1983
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• 2006

Kaempferol was isolated and identified from the methanol extract of the flowers of Impatiens balsamina. Kaempferol showed inhibitory activity against mushroom tyrosinase with an $ID_{50}$ of 0.042 mM. Inhibition kinetics, as determined using a Lineweaver-Burk plot, showed kaempferol to be a competitive inhibitor of mushroom tyrosinase with a $K_i$ value of 0.011 mM. The lag phase of tyrosine hydroxylation catalyzed by mushroom tyrosinase clearly increased on increasing the concentration of kaempferol. In addition to its tyrosinase inhibiting activity, kaempferol strongly inhibited melanin production by Streptomyces bikiniensis, in a dose-dependent manner, without inhibiting cell growth. For comparative purposes, the tyrosinase inhibitory activity of kaempferol was also assayed versus quercetin, a positive standard.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.477-480
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• 2002

The purpose of this study Was to investigate the effects of ponding depth treatment on water balance in paddy fields. Three ponding depth treatment, shallow, traditional, and deep were used. Daily values of rainfall amount, ponding depth, irrigation water, drainage water, evapotranspiration, and infiltration were measureed in the field. The results showed that irrigation water depths were 198mm, 195mm, and 355mm in shallow, traditional, and deep ponding, respectively. The three treatments did not show any statistical difference in growth and yields. Shallow depth treatment showed the largest yield.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.2
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• pp.47-52
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• 2020

Air transport demand is on a sharp rise due to growth in the aviation market. To prepare for this rapidly growing demand for aviation, airport operators are interested in the processing airport capacity. Airport throughput is determined to be the smallest of the facility capacities that make up the airport, but it is customary to determine the cost and time consuming runway capacity as airport capacity. Previous studies have shown that while recent studies have been conducted on airport capacity, there is little research on the criteria for determining capacity. In this study, we would like to determine the extent to which airport capacity is affected by the airport's operating hours and the resulting delays.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.96-100
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• 2001

Three commercial strains bred in the US (Hubbard), Holland (Lohman), and Canada (Shaver) and Balady breed of chickens were orally infected with $10^6$ cfu of Salmonella gallinarum per chick. Chicks were compared for weight gain, feed intake, feed conversion ratio, mortality rate and contamination of the liver, spleen and intestine with Salmonella gallinarum on the day of slaughter. The Balady chicks had significantly the lowest mortality rate (p<0.01) and weight gain (p<0.001) and poorest feed conversion ratio (p<0.001). Salmonella gallinarum could be shed from the liver, spleen and intestine with alternative rates in all strains. Lohman was the most resistance over the other two commercial strains, while Hubbard had the highest susceptibility. The Balady chicks were the most resistance. However, they may serve as a possible reservoir of Salmonella gallinarum and it may play a role of spreading the infection to the commercial farms in Jordan.