• Environmental Mutagens and Carcinogens
• /
• v.18 no.2
• /
• pp.83-88
• /
• 1998

To detect the mutation in a given sequence, there are variety of methods developed by use of the gel electrophoresis. One of the methods, TGGE (Temperature Gradient Gel Electrophoresis), is a popular technique because it can detect mutations in DNA fragment with ease and at low cost. This study used 200 bp BamHI-digested DNA fragment containing the human $\varepsilon$-globin promoter which was mutated[$\varepsilon$ F1*(-141), GATA- I*(-163), and GATA-1* & $\varepsilon$F1]. This BamHI-digested DNA fragment was directly used to detect the mutated DNA fragment on 50% denaturant gel with temperature gradient of 45$^{\circ}C$ through $53^{\circ}C$. In agreement with the theoretical result of MELTSCAN program (Brossette and Wallet, 1994) the mobilities of mutated DNA fragments were shown to be nearly distinguished on the temperature gradient gel. In contrast to the above result the heteroduplex analysis under the temperature gradient condition was shown to detect the mutated DNA fragments through the heteroduplex formation between strands of mutated DNA and wild-type DNA.

• Journal of Life Science
• /
• v.18 no.10
• /
• pp.1325-1330
• /
• 2008

Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

• Journal of Animal Environmental Science
• /
• v.21 no.1
• /
• pp.21-28
• /
• 2015

We studied the possibility on the application of the Thermophilic Aerobic Oxidation (TAO) process to anaerobic digestate stabilization. In treating digestate with TAO reactor the internal temperature of the reactor was increasing higher and $51^{\circ}C$ and over was maintained after 6 days on. The physiochemical compositions of liquids increased from pH 8.1 to 9.8 and EC decreased from 29.8 to 12.0 mS/cm in treating process of digestate with TAO reactor. CODcr decreased from 22,654 to 18,843 mg/L, showed about 16.82% of remove efficiency. TN and $NH_4-N$ decreased from 4,813 to 1,733 mg/L, from 3,815 to 812 mg/L respectively, which showed about 64.0% and 78.7% of removal efficiency respectively.

• Journal of the Korean Society for Precision Engineering
• /
• v.26 no.3
• /
• pp.137-143
• /
• 2009

It has been reported that mechanical stimulation takes a role in improving eel/ growth in skeletal system. Various research groups have been showed their own bioreactors which stimulate cell-seed three-dimensional scaffold. In this study, we hypothesized that the various conditions of mechanical stimulation would affect cell growth and proliferation. To prove our hypothesis, we designed a custom-made bioreactor capable of applying controlled compression to cell-encapsulated scaffolds. This device consisted of a circulation system and a compression system. Each parts of the bioreactor was fabricated using the rapid prototyping technology By using the rapid prototyping technology, we can modify and improve the bioreactor very rapidly For dynamic cell-culture, cell-encapsulated agarose gel was fabricated in 2% concentration. We performed dynamic cell-culture using this agarose gel and developed bioreactor in 3 days.

• Journal of Veterinary Clinics
• /
• v.17 no.1
• /
• pp.145-151
• /
• 2000

황색포도상구균이 Capsular polysaccharide (CPS)는 백혈구의 탐식에 저항하기 때문에 젖소의 유방염 발생의 중요한 병원상 인자로 오랫동안 연구자들의 관심이 집중되어 왔다. 따라서 CPS는 젖소의 유방염을 최소화시키기 위한 유방염 백신개발에 있어 잠재적인 백신 항원물질로 알려져 왔다. 본 연구의 복적은 황색포도상구균의 CPS 항원물질을 좀더 효과적으로 발현시키고 향후 백신항원으로 사용시 좀 더 간편하게 정제하는 방법을 찾아보고자 본 연구를 수행하였다. CPS는 락토스와 덱스트로스를 첨가한 brain heart infusion media 에서도 부분적으로 발현되었지만 CPS가 가장 잘 발현되는 배지 조건은 젖소 유래의 유청을 10% 첨가한 조건에서 가장 발현율이 높았다. 또한 CPS발현은 salt agglutination test, india ink법 및 투과전자현미경을 이용하여 확인하였으며 균체표면의 hydrophobicity에서는 락토스, 덱스트로스 및 젖소 유래의 유청을 첨가한 배지조건에서 다른 조건에 비해 높았다. CPS의 가장 손쉬운 검사법은 균체를 절편하지 않고 직접 투과전자현미경상에서 염색없이 관찰하는 것이 가장 간편한 방법이었다. CPS정제는 상층액을 농축시킨후 이온교환크로마토그라피와 젤 여과법을 이용하여 정제하였으며 CPS의 분자량은 대부분 97kDa이상이었다. CPS 회수율은 배지와 균체 1리터당 1.5mg이었다. 결론적으로 CPS를 백신항원으로 포함하고자 할 경우, CPS의 최적 발현조건은 젖소 유래의 유청을 10% 첨가한 Brain heart infusion 배지에서 배양하여 사용하는 것이 가장 좋은 방법이라고 생각된다.

• Korean Journal of Microbiology
• /
• v.27 no.3
• /
• pp.245-249
• /
• 1989

Extracellular proteases of Bacillus licheniformis were partially purified using ammonium sulfate fractionation and Sephadex G-75 gel filtration chromatography. The partial purification permited the weparation of two different protease activities, type I and type II. Protease type I is an enzyme with rather high protealytic activity toward dasein and was highly susceptible to organofluoride and EDTA inhibitions. It showed maximal proteolytic activity at pH 7.5 and was rapidly denatured at $71^{\circ}C$. Protease type II is a protease with relatively lower proteolytic activity than the type I. It was also inhibited by 10mM of EDTA and 1mM of PMSF by 30 min incubation. The enzyme showed maximal activity at pH 8.0 and was denatured relatively slowly at $71^{\circ}C$.

• Polymer(Korea)
• /
• v.34 no.3
• /
• pp.261-268
• /
• 2010

Phase change materials based on polypropylene blended with n-eicosane were studied in this paper. In addition, this paper reviews recent studies on the preparation of shape stabilized phase change materials (SSPCM), such as SSPCM from polypropylenes and n-eicosane, their basic properties and possible applications to latent heat storage. The preparation methods used were the melting method and absorption methods. Shape stabilized PCM(SSPCM) prepared for DSC, WAXD, FTIR spectroscopy, ARES, results of the analysis of shape stability heat capacity to improve were identified.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.11a
• /
• pp.128-128
• /
• 2003

Electrochromism (EC) is defined as a phenomenon in which a change in color takes place in the presence of an applied voltage. Because of their low power consumption, high coloration efficiency, EC devices have a variety of potential applications in smart windows, mirror, and optical switching devices. An EC devices generally consist of a transparent conducting layer, electrochromic cathodic and anodic coloring materials and an ion conducting electrolyte. EC has been widely studied in transition metal oxides(e.g., WO$_3$, NiO, V$_2$O$\sub$5/) Among these materials, WO$_3$ is a most interesting material for cathodic coloration materials due to its lush coloration efficiency (CE), large dynamic range, cyclic reversibility, and low cost material. WO$_3$ films have been prepared by a variety of methods including vacuum evaporation, chemical vapor deposition, electrodeposition process, sol-gel synthesis, sputtering, and laser ablation. Sol-gel process is widely used for oxide film at low temperature in atmosphere and requires lower capital investment to deposit large area coating compared to vacuum deposition process.

• Journal of Pharmaceutical Investigation
• /
• v.37 no.2
• /
• pp.85-94
• /
• 2007

The objective of this study is to prepare a stable delivery systems containing polyethoxylated retinamide(PERA) - derivatives of retinoic acid, effective anti-wrinkle and anti-acne agent. Cubic liquid crystalline phase gel (CLCPG) and cubosomes containing various concentrations of PERA were prepared to investigate the physicochemical properties. Furthermore, stability and transdermal absorption efficacy of the CLCPG containing PERA were investigated in comparison with oil-in-water (O/W) emulsions which are predominantly used as a topical formulation. CLCPG increase the stability of PERA in comparison with O/W emulsion. For tropical application, CLCPG containing PERA shows higher moisturizing effect than that of O/W emulsion. In skin permeation test, CLCPG shows higher PERA deposit on epidermis. With its specific physicochemical property caused by the glyceryl oleate, CLCPG itself could be used for stabilizer of various actives and applied as an effective delivery system for topical application. Cubosome, nano-sized dispersed CLCPG, is also expected to be applied in a various field of industry like food, cosmetics and pharmaceuticals.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.4
• /
• pp.852-856
• /
• 2009

Poly(ethyleneglycol methacrylate-co-benzyl methacrylate) (P(PEGMA-co-BMA)) microgel was prepared by precipitation copolymerization of PEGMA and benzyl methacrylate in poly(acrylic acid)/ethanol solution. The microgels with various sizes were obtained by changing the concentration of poly(acrylic acid), monomer and nature of solvents. The particle size of P(PECMA-co-BMA) microgels was decreased with increasing the concentration of poly(acrylic acid) and increased with that of monomer. By increasing solubility parameter of solvents, the particle size was inecreased. The size of P(PEGMA-co-BMA) microgels was controlled by experimental conditions from $0.1{\mu}m$ to $0.35{\mu}m$.