• Polymer(Korea)
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• v.28 no.4
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• pp.344-351
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• 2004

Poly(ethylene glycol)-based diblock and triblock polyester copolymers stimulating to temperature were studied as injectable biomaterials in drug delivery system because of their nontoxicity, biocompatibility and biodegradability. We synthesized the diblock copolymers consisting of methoxy poly(ethylene glycol) (MPEG) (M$_{n}$=750 g/mole) and poly($\varepsilon$-caprolactone) (PCL) by ring opening polymerization of $\varepsilon$-CL with MPEG as an initiator in the presence of HCl . Et$_2$O. The aqueous solution of synthesized diblock copolymers represented sol phase at room temperature and a sol to gel phase transition as the temperature increased from room temperature to body temperature. To confirm the in vivo gel formation, we observed the formation of gel in the mice body after injection of 20 wt% aqueous solution of each block copolymer. After 2 months, we observed the maintenance of gel without dispersion in mice. In this study, we synthesized diblock copolymers exhibiting sol-gel phase transition and confirmed the feasibility as biomaterials of injectable implantation.n.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.639-642
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• 2003

Olfactory receptor protein ODR10 was expressed in E.coli as fusion protein with GST and His6 Tag. Crude membrane extract of the expressed protein was coated on the surface of quartz crystal microbalance, and the interaction of the ODR10 with several odorants was examined. Although the expression level was very low, quartz crystal microbalance showed that the expressed protein interacted most strongly with diacetyl (butanedione), which is known to bind to the ODR10 protein selectively. The interaction between ODR10 and diacetyl was $5{\sim}10$ times stronger than the interaction between ODR10 and other odorants. Thus, E. coli cells expressing the olfactory receptor protein could be used as an olfactory biosensor. Also, such system could be used to test which olfactory receptor reacts specifically with which odorant molecules, since there has been no cheap and convenient way to test the interaction of olfactory receptors and odorant molecules yet.

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.245-250
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• 1996

This research was performed to find out the changes of serotonin receptors in the platelet of alcoholics. Using $_{125}I-LSD$ as a radioligand. We obtained the following results. 1) In the comparison of patients vs controls, $B_{max}$ of the former was significantly higher than that of the latter(P=0.0017). But there was no significant difference in the Kd between the two groups. 2) In the comparison of type 1 vs type 2, alcoholics by cloninger's classification $B_{max}$ of the latter was significantly higher than that of the farmer(P=0.0396). But there was no significant difference in the Kd between the two groups. 3) In the comparison of alcohol abuse vs alcohol dependence, there were no significant differences in the value of $B_{max}$ and Kd between the two groups. These results support the hypothesis of serotonin-deficit in alcoholism. Furthermore, it can be inferred that the increase of platelet serotonin receptors in alcoholics might be used as a trait marker.

• Analytical Science and Technology
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• v.17 no.1
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• pp.53-59
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• 2004

Up to now, methods for the detection of genetic alterations as single strand conformation polymorphism (SSCP) or denaturing gradient gel electrophoresis (DGGE) have been used. It is too labor-intensive and expensive to serve for routine analysis. Moreover, lower in its sensitivity and specificity being also strongly dependent on the experience of the investigater. To improve these problems, we analysed mutation of ${\beta}_2$-adrenergic receptor gene that controls bronchial asthma by denaturing high performance liquid chromatography (DHPLC) according to ion-pair reversed phase chromatography (IP-RPC). We extracted genomic DNA from 80 asthma patients and then amplified DNA using PCR and analysed PCR product by SSCP and DHPLC. As a result, we analysed mutation frequency is 19 (23.75%) on SSCP and 25 (31.25%) on DHPLC in ${\beta}_2$-adrenergic receptor gene. We conclude that DHPLC is a fast and simple screening method rather than SSCP analysis.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.707-708
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• 2000

Colloidal gold with a conducting polymer (e.g., polyaniline) bound on the metal surfaces has been used for the generation of conductimetric signal in a membrane strip immunosensor. Since polyaniline itself at a low pH range revealed a low conductivity, an approach of doping the polymer with a lithium salt was used. As an alternative method, a self-doped (i.e., pH-independent) sustance such as leucoemeraldine base sulfonated polyaniline (LEB-SPAN) can be used as signal generator. It was also highly soluble in water and, thus, such a selected polymer was expected to support a satisfactory property as a label of the immunosensor.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.245-252
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• 1993

To investigate a simple and rapid screening method for photosynthetic inhibitory herbicides, responses of tobacco(Nicotiana tabacum L.) and liverwort(Marchantia polymorpha L.) PA(photoautotrophic) cells to various commercial herbicides with different modes of action and leaf extracts of four weed species were compared. PET (photosynthetic electron transport) inhibitory type of herbicides has greater inhibitory effect in liverwort photoautotrophic cells than the photomixotrophic and heterotrophic cultured cells. Similary, PET inhibitory type of herbicides inhibited the oxygen evolution more in liverwort PA cells than the other type of herbicides. Based on oxygen evolution, 60% inhibition was observed by the 10% aqueous extracts of Polygonum hydropiper, while there was 100% inhibition by the 10% methanol extracts of Polygonum hydropiper. This assay gave well correlated results to the Hill reaction data using isolated thylakoids. Thus liverwort photoautotrophic cells might be suitable materials for rapid screening method for photosynthetic inhibitory herbicides.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.2
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• pp.75-82
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• 2008

In this study, the photocatalysed degradation of safranin-O was investigated using Au colloids. Au metal nanoparticle wasused to eliminate safranin-O fast in solution. Au nanoparticles were prepared reduction method using $Na_2CO_3$ and PVP in aqueous solution. The degradation of safranin-O was examined using a variety of condition such as concentration of Au colloid or Au salt, reaction pH, and reaction time in the presence of UV light and $H_2O_2$. As the concentration of Au colloid increases, the rate of dye degradation increases. The photo-oxidation of the safranin-O was monitored spectrophotometrically. The properties of Au nanoparticles were characterized by UV-Vis spectroscopy. In addition, catalytic capacities of Au nanoparticles were also determined by UV-Vis spectroscopy.

• Science of Emotion and Sensibility
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• v.23 no.2
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• pp.75-88
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• 2020

Given the development of information technology, various methods for efficient information delivery have been constructed as the method of delivering product information moves from offline and 2D to online and 3D. These attempts not only are about delivering product information in an online space where no real product exists but also play a crucial role in diversifying and revitalizing online shopping by providing virtual experiences to consumers. 360 product image is a photorealistic VR that allows a subject to be rotated and photographed to view objects in three dimensions. 360 product image has also attracted considerable attention considering that it can deliver richer information about an object compared with the existing still image photography. 360 product image is influenced by divergent production factors, and accordingly, a difference emerges in the responses of users. However, as the history of technology is short, related research is also insufficient. Therefore, this study aimed to grasp the responses of users, which vary depending on the type of products and the number of source images in the 360 product image process. To this end, a representative product among the product groups that can be frequently found in online shopping malls was selected to produce a 360 product image and experiment with 75 users. The emotional responses to the 360 product image were analyzed through an experimental questionnaire to which the semantic classification method was applied. The results of this study could be used as basic data to understand and grasp the sensitivity of consumers to 360 product image.

• Journal of Information Technology and Architecture
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• v.10 no.2
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• pp.223-236
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• 2013

Related to the situation on the Korean Peninsula, by North Korea's threat of war the tension escalates and serious crisis continues. The purpose of this study is to evaluate the subjective perception which the residents of South Korea feel about North Korea's threat of war through a Q methodological analysis framework. In the result of the study, for the North Korea's threat of war the South Korean's recognition type is analyzed into four type such as 'non-reactive', 'fearreactive', 'psychological anxiety' and 'cynical ignorance type'. First, the No. 1 type 'non-reactive' does not empathize with North Korea's threat of war itself, and second type 'fear-reactive' have uneasy feeling like that 'What would happen as things go' and feel a sense of crisis about the North Korea's threat of war. The third type 'psychological anxiety' is type which feels that due to North Korea's threat of war inter-Korean relations is in the crisis. Finally the fourth type 'cynical ignorance' think that North Korea's threat of war is bluffing and also North Korea is like a shepherd boy. The reason to apply Q-methodology in this study is to make it possible to a more in-depth approach to subjective perception and threat of psychological meaning for the threatening message of study participants.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.287-300
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• 2021

The purpose of this study is to verify the influence relationship of digitally converted services on consumers' intention to use since traditional services are being converted to digital services due to technological development and increase in non-face-to-face services. The study consisted of a program development procedure and a program effectiveness verification procedure, and bootstrapping was performed to verify the mediating effect adjusted along with multiple regression analysis. The subjects of this study were 323 university (graduate) students and the general public residing in Korea. Results. First, it was found that the three perceived interaction factors (perceived communication, perceived control, and perceived reactivity) of digital transformed services had a positive effect on perceived usefulness and perceived ease of use, respectively. Second, the relationship of influence of technology acceptance intention was verified. Third, it was confirmed that the effect of the three perceived interaction factors of digital transformed services on intention to use was mediated by perceived usefulness and perceived ease of use. Fourth, the mediating effect mediated by digital disparity was confirmed. As a result, it was confirmed that the three perceived interaction factors of the digitally converted service are important factors in the intention to use the digitally converted service. This suggests that efforts are needed to minimize the digital divide.