• BMB Reports
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• 제28권6호
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• pp.477-483
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• 1995

The recombinant human interferon alpha 2a ($rhIFN-{\alpha}2a$), expressed in Saccharomyces cerevtsiae, was purified from insoluble aggregates. The inclusion body of $rhIFN-{\alpha}$ was solubilized by guanidine salt in the presence of disulfide reducing agent. The refolding of denatured $rhIFN-{\alpha}2a$ was achieved by simple dilution. The authentic interferon alpha, which has two correctly matched disulfide bonds, was seperated from incompletely oxidized $IFN-{\alpha}$ and dimeric $IFN-{\alpha}$ by use of a CM-Sepharose column, followed by size exclusion columns at two different pH conditions. The purified protein has been subjected to detailed physicochemical characterization including sequence determination. Unlike other $rhIFN-{\alpha}2a$ from E. coli reported, the $rhIFN-{\alpha}2a$ from S. cerevisiae has no methionine residue at its N-terminus originating from the start codon, ATG. The pI of the protein was determined to be 6.05 with a single band in the pI gel, which demonstrated that the purified $rhIFN-{\alpha}$ was homogeneous. The structural study using circular dichroism showed that the protein retains its three dimensional structure in the wide range of pH conditions between pH 3 and 9, and only minor strucural deformation was observed at pH 1.0.

• BMB Reports
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• 제28권5호
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• pp.437-442
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• 1995

The potency of yeast-derived methionyl-free human growth hormone (rhGH), which was obtained by removal of the N-terminal Met from methionyl-hGH, was estimated by in vitro and in vivo assays. In radio-receptor assay where the binding affinity of growth hormone to the receptor was estimated, the recombinant hGH showed 2.9 international units (IU) per mg of specific activity. In contrast, pitUitary-derived human growth hormone had a slightly lower receptor binding activity (2.5 IU/mg) compared with recombinant growth hormone. For the in vivo assay, efficacy of rhGH was tested by use of hypophysectomized rats, in which pituitary organs were surgically removed, resulting in the termination of growth hormone secretion. The weight-increase in rats by the injection of rhGH was almost identical to the result obtained by the injection of the same amount of pituitary-derived (international standard) hGH. A comparision of the secondary structures of rhGH and rMet-hGH by circular dichroism spectrophotometer demonstrated that the removal of the methionyl residue from rMet-hGH did not exert any effect on the structure of the growth hormone. In conclusion, methionyl-free human growth hormone produced from yeast was highly potent in biological activity and maintained a legitimate three dimensional structure.

• Archives of Pharmacal Research
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• 제19권6호
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• pp.554-558
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• 1996

High-performance liquid chromatographic method was developed for the determination or LB 20304 (compound 1) in the plasma of rats and dogs. The analyte was deproteinized with 1 volume of methanol and 1/2 volume of 10% zinc sulfate, and the supernatant was injected onto a reversed-phase HPLC column. The mobile phase was a mixture of 24 parts of acetonitrile and 76 parts of 0.1% trifluoroacetic acid. The flow rate was 1 ml/min, and the effluent was monitored by fluorescence detector at an excitation wavelength of 337 nm and an emission wavelength of 460 nm. The retention time of compound 1 was 6.3 min. The assay of compound 1 was linear over the concentration range of 0.2-100.mu.g/ml in the plasma of rats and dogs. The lower limit of quantification was 0.2.mu.g/ml using 100.mu.l of plasma with a 97-99% accuracy and a 12-14% precision. In the 0.5, 5, and 50.mu.g/ml quality control samples, the intra- and inter-day accuracy were 88-95% and 88-97%, whereas intra- and interday precision were 0.5-6.6% and 0.2-9.3%, respectively, in the plasma of rats and dogs. The recoveries were 68-71% independent of concentration and species in the plasma. No interferences from endogenous substances were observed. Taken together, the above HPLC assay method by deproteinization and fluorescence detection was suitable for the determination of compound 1 in the preclinical pharmacokinetics.

• 디지털융복합연구
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• 제11권10호
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• pp.263-275
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• 2013

최근 M&A는 기업의 경쟁력을 확보하기 위한 중요한 전략적 의사결정이며 이러한 M&A를 추진하는 기업들은 증가하고 있는 추세이다. 그러나 M&A의 성공은 흔한 일이 아니며 M&A가 성공하기 위해서는 인수기업의 최고경영자의 리더십과 함께 인적통합전략의 실천으로 구성원에 대한 관리가 선행되어야 할 것이다. 이에 본 연구에서는 M&A기업들이 궁극적인 성공을 위해서 구성원들의 변화에 대한 저항을 극복하는 것이 중요하다는 인식을 바탕으로, 성공적인 M&A를 마무리하고 성과를 내고 있는 LG화학(현대석유화학 인수) 사례를 중심으로 최고경영자의 리더십과 인적통합전략이 구성원들의 변화저항, 수용 그리고 성과에 미치는 영향을 실증적으로 규명하고자 한다. 이를 위해 먼저 최고경영자의 리더십과 인적통합전략 등 기존 연구를 살펴보았으며 이를 기반으로 LG화학(대산공장) 담당자 및 구성원들과의 인터뷰를 통해 M&A이후 최고경영자의 전략적 리더십과 인적통합이 어떻게 발현되는지를 살펴보았다. 그 결과 인수기업을 빠른 시일 내에 정상화하기 위해서는 최고경영자의 전략적 리더십과 인적통합전략이 중요한 변화동인임을 확인할 수 있었다. 이러한 사례연구를 통해 M&A이후 실질적인 통합방안과 리더십 발현방안을 제안하여 향후 M&A를 추진하는 기업들에게 시사점을 제공하고자 한다.

• 한국자기공명학회논문지
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• 제7권2호
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• pp.74-79
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• 2003

Li[Ni,Mn,Co]O$_2$ electrode has been studied by $\^$7/Li MAS NMR. A sharp resonance at -1 ppm and a very broad resonance at approximately 400 ppm are assigned to the Li ions in Co-only environment and Ni/Mn(Co) environment, respectively, indicating a segragation of Co ions and Ni/Mn ions. Different temperature behavior of the peak position is observed for Co-only environment and Ni/Mn(Co) environment. Oxidation of Ni ions is involved during the entire charging process. At high temperature, a peak narrowing caused by the electron hopping is observed.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.380-380
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• 2006

Styrene-Butadiene diblock or styrene-butadiene-styrene triblock copolymers are industrially important materials for asphalt modification and adhesives. A kinetic modeling study on non-isothermal anionic styrene-butadiene diblock copolymerization system is presented. The model deals with the association/dissociation reaction of initiator and propagating ion pairs in its kinetic scheme. By comparing model calculation results with real plant data, it is possible to obtain useful ideas for more efficient plant operation. For example, the model clearly provides important relation between the reaction temperature profile and the conversion of monomers.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.537-538
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• 2006

Split and recombine type reaction module was made by electrical discharge machining. The reaction module has special features to well mix the two reactants which have high flow ratio or high concentrations difference. It could be achieved by deviding one flow equally by two and inserting second flow in between. The mixing performance was measured by a parallel competing reaction with iodide-iodate system. The result shows that the developed three inlets micromixer has better mixing efficiency than comercialized Y type micromixer.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.205-212
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• 2011

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.49-57
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• 2011

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.305-308
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• 2008

We performed coupled-cluster calculations to determine the intermolecular interaction energy between two TiAu4 clusters. Our ab initio calculations predict that the binding energy is 2.89 eV, which is somewhat larger than the known binding energy of 2.0 eV for TiH4-TiH4. The intermolecular binding energy is relatively high, despite TiAu4 having all the attributes of a magic cluster. The favorable orbital interaction between occupied Au(6s) and unoccupied Ti(3d) orbitals leads to the strong dimeric interaction for TiAu4-TiAu4.