• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 춘계학술대회 논문집
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• pp.43-46
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• 2004

Since Mg alloy has many attractive advantages among the practically used metals, many researchers have been studied to develop useful process and material. However, study for sheet forming has not been a few because of low formability on room temperature. Formability and springback for AZ31 alloy sheet have been studied to develop the cold forming technology. The experimental and FE analysis were performed to analyzed the springback amounts by using a model of our on. A different three materials were used to investigate the effects of material characteristics. The springback amounts of Mg-alloy sheet formed part were larger than that of the other material.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.880-886
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• 2015

Bacterial heme was produced from a genetic-engineered Escherichia coli via the porphyrin pathway and it was useful as an iron resource for animal feed. The amount of the E. coli-synthesized heme, however, was only few milligrams in a culture broth and it was not enough for industrial applications. To analyze heme biosynthetic pathways, an engineered E. coli artificially overexpressing ALA synthase (hemA from Rhodobacter sphaeroides) and pantothenate kinase (coaA gene from self geneome) was constructed as a bacterial heme-producing strain, and both the transcription levels of pathway genes and the intermediates concentrations were determined from batch and continuous cultures. Transcription levels of the pathway genes were not significantly changed among the tested conditions. Intracellular intermediate concentrations indicated that aminolevulinic acid (ALA) and coenzyme A (CoA) were enhanced by the hemA-coaA co-expression. Intracellular coproporphyrinogen I and protoporphyrin IX accumulation suggested that the bottleneck steps in the heme biosynthetic pathway could be the spontaneous conversion of HMB to coproporphyrinogen I and the limited conversion of protoporphyrin IX to heme, respectively. A strategy to increase the conversion of ALA to heme is discussed based on the results.

• 원예과학기술지
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• 제30권3호
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• pp.342-344
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• 2012

A new grafted cactus cultivar, called 'Hwangseon', Gymnocalycium mihanovichii, is a hybrid crossed between two orange color cultivars 'Geoseong' and 'Huhwang'. Mating was performed in the greenhouse of National Institute of Horticultural & Herbal Science (NIHHS) in 2005. The harvested seeds were sown at 100 mL volumetric flasks filled with 'Kyoto' medium. Seedling had been grafted into a young rootstock, Hylocereus trigonus, and cultured in vitro in 100 mL test tube for more than six months. After re-grafting and planting in the green house in 2006, their characteristics were evaluated three times until 2009. The new cultivar has a flat round shape and bright yellow skin color. In addition, it has 7 to 9 ribs with gray and straight spines on the body and produces an average of 12.3 offsets.

• Asian-Australasian Journal of Animal Sciences
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• 제24권11호
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• pp.1569-1576
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• 2011

Accurate assessment of the nutritional status of Nguni cattle is becoming increasingly important in determining their mechanism for adaptation to challenging environments. Changes in body weights and concentrations of total protein (TP), albumin, globulin, glucose, cholesterol, non-esterified fatty acids (NEFA), phosphorus (SIP), calcium and magnesium were determined in Nguni and crossbred calves raised on natural pasture from birth until weaning. At an early age, TP concentration in crossbreds was higher (p<0.05) than that of Nguni calves. However, TP levels increased with age in Nguni calves so that Nguni's had higher (p<0.05) TP levels than crossbreds at weaning. Nguni calves had higher (p<0.05) glucose concentrations than crossbreds in all the ages except in the third month. Serum NEFA levels in Nguni calves were higher (p<0.05) than in crossbreds at all ages except for the second month. Calcium levels decreased (p<0.05) with age in both genotypes. The blood TP concentrations tended to decrease (p<0.05) as body weight increased up to 80 kg, thereafter blood TP concentration increased (p<0.05) as body weight increased. Calcium concentrations in crossbred calves decreased (p<0.05) quadratically as the body weight increased. There was, however, a linear increase (p<0.05) in calcium concentrations in Nguni calves. The higher NEFA and TP concentrations at weaning and the TP increase in Nguni calves beyond 80 kg suggest that Nguni's utilise fibrous feeds better than crossbreds.