• Journal of Pharmaceutical Investigation
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• v.31 no.3
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• pp.191-196
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• 2001

Biodegradable polymeric microspheres were studied for their usefulness as carriers for the delivery of vaccine antigens. However, protein antigen could be denatured during microencapsulation processes due to the exposure to the organic phase and stress condition of cavitation and shear force. Therefore this study was carried out to re-evaluate the degree of protein denaturation during microencapsulation with poly(lactide-co-glycolide) (PLGA) copolymer. PLGA microspheres containing ovalbumin (OVA), prepared by W/O/W multiple emulsification method, were suspended in pH 7.4 PBS and incubated with shaking at $37.5^{\circ}C$. Drug released medium was collected periodically and analyzed for protein contents by micro-BCA protein assay. In order to evaluate the protein integrity, release medium was subjected to the analyses of SDS-PAGE and size exclusion chromatography (SEC). And enzyme-linked immunosorbent assay (ELISA) was introduced to measure the immunoreactivity of entrapped OVA and to get an insight into the three-dimensional structure of epitope. The structures of entrapped protein were not affected significantly by the results of SDS-PAGE and SEC. However, immunoreactivity of released antigen was varied, revealing the possibility of protein denaturation in some microspheres when it was evaluate by ELISA method. Therefore, in order to express the degree of protein denaturation, antigenicity ratio (AR) was obtained as follows: amount of immunoreactivity of OVA/total amount of OVA released ${\times}100(%)$. ELISA method was an efficient tool to detect a protein denaturation during microencapsulation and the comparison of AR values resulted in more accurate evaluation for immunoreactivity of entrapped protein.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.91-99
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• 2011

Adult-learners of online education have been distant from studying for a long time and are rather familiar with the old massive education. As a result, despite the excellent ability in self-control learning that results in great academic performances and academic continuity, the learners give up on learning, feeling depressed for not being able to perform their advantage, the self-control learning ability. The study developed a self-control learning model and UDL design learning model in order to establish e-mentoring system. For the analysis on results of the experiment, the researcher extracted academic grade, the rate of re-register, and the amount of total studying time after dividing new students and transfer students of H cyber university into the control group and the experimental group. In conclusion, the results showed that more satisfied the control group is, the higher academic achievements and the higher academic continuity are accomplished.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1107-1113
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• 2010

Because conventional methods for detecting emetic-toxin-producing B. cereus are laborious and costly, various PCR assays, which are easy and cheap, have recently been reported. Therefore, this study estimated and compared the ability of various PCR assays to detect emetic-toxin-producing B. cereus strains isolated in Korea. The PCR assays were performed on 160 B. cereus strains, including 40 emetic-toxin-producing strains. Although the species-specific PCR assays were all shown to be highly specific, the sensitivities varied greatly. The accuracies of the primers were 97.5% (CER), 95.6% (EM1), 96.3% (RE234), 89.4% (CES), and 83.1% (Ces3R/CESR2). Moreover, the CER primer had a higher sensitivity (100%) than all the other primers tested, and a specificity of 96.7%. Thus, the CER primer was shown to be the most effective for screening the emetic-toxin-producing B. cereus strains tested in this study. However, the ability of these PCR assays to identify emetic-toxin-producing B. cereus should also be confirmed using other methods.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.6
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• pp.1-16
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• 2003

This study seeks to find new strategies for the development of Tapgol Park and to identify Programs to promote this development. In addition, the study specifies the purpose and meaning of these efforts by revealing social aspects not apparent in the physical form of the site, and reading how these aspects influenced the development of Tapgol Park Because the focus of the study lies in reading cultural aspects of the site which have to be understood within the context of their social circumstances, the study drew materials from mass media such as newspapers and literary magazines, which best reflect these social aspects. Interpreting the over 100 you history of Tapgol Park in a cultural context, the study found a meaningful suggestion that such a small urban place located in a city forms a cultural identity in the course of communicating with its surrounding social situations. The change in the identity of Tapgol Park has been sensitive to changing social circumstances rather than the physical structure of the space. The original function of Tapgol Park as a traditional city park has gradually changed towards strengthening social functions, much like the character of an urban plaza. In the process of change the park developed a unique culture. This park culture, however, came not from the original design but from its close interactions with social circumstances changing over time. At the same time, the change in identity seen in Tapgol Park has not been fresh formed. It can be said that the inertia came into light with the potential powers under the place over the long history having been combined into the then social circumstances. In early 2002, the park re-opened, refurbished as one of the relics of the March 1st Movement. Investigating how cultural inertias that have been developing in various forms to date will change and be maintained in this new paradigm is an important assignment for researchers.

• Safety and Health at Work
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• v.2 no.1
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• pp.52-56
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• 2011

Objectives: The occupational accident rate was officially reported to be 0.77 per 100 workers in 2001 and 0.70 in 2009. The stagnant decrease in accident rate raises a question about the effectiveness of prevention activity because there have been active prevention efforts in the past 10 years. It is also necessary to know the exact status of occupational injuries to direct a prevention strategy. Methods: The author re-analyzed occupational injury statistics to find the reason for stagnant decreases in occupational injuries. Compensated occupational injuries cases were used to calculate fatal and non-fatal injury rates. Injuries from commuting accidents and sports activities were excluded as well as occupational diseases. The number of workers was adjusted to that of full time equivalent employees. Results: The fatal injury rate excluding injuries associated with commuting accidents, sports activities, and occupational diseases decreased from 12.59 in 2001 to 8.20 in 2009. In 2007, 67.5% of accidents that involved being caught in objects, which are mostly caused by machines and equipment, occurred in the manufacturing industry; this type of incident has decreased since 2001. The fatal and non-fatal injury rates in the manufacturing industry have continuously decreased while the rates in the service industry have not changed from 2001 to 2009. Non-fatal injuries might not be reported in many cases. The number of insured workers was underestimated as long working hours were not adjusted for in the reporting system. Conclusion: The occupational fatal injury rate has decreased and the non-fatal injury rate might have decreased during the last 10 years, although the statistics show stagnancy. The decrease of the injury rate was countervailed by various factors. Hence, the current accident rate does not reflect the actual situation of accidents in Korea. Korea needs to develop an improved system to more accurately calculate occupational fatal and non-fatal injury rates.

• Journal of Welding and Joining
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• v.24 no.2
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• pp.64-70
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• 2006

The 3-dimensional (3D) chip stacking technology is a leading technology to realize a high density and high performance system in package (SiP). There are several kinds of methods for chip stacking, but the stacking and interconnection through Cu filled through-hole via is considered to be one of the most advanced stacking technologies. Therefore, we studied the optimum process of through-hole via formation and Cu filling process for Si wafer stacking. Through-hole via was formed with DRIE (Deep Reactive ion Etching) and Cu filling was realized with the electroplating method. The optimized conditions for the via formation were RE coil power of 200 W, etch/passivation cycle time of 6.5 : 6 s and SF6 : C4F8 gas flow rate of 260 : 100 sccm. The reverse pulsed current of 1.5 A/dm2 was the most favorable condition for the Cu electroplating in the via. The Cu filled Si wafer was chemically and mechanically polished (CMP) for the following flip chip bumping technology.

• Proceedings of the Korean Vacuum Society Conference
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• 1994.02a
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• pp.43-43
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• 1994

We studied chemical reactio of Eu metal on the in situ cleaved CdTe(110) surface by pphotoemission sppectroscoppy using synchrotron radiation. The chamber was maintained with base ppressure $\leq$2${\times}$10-10 mb during the expperiment. The expperiment was carried out in pphoton Factory in Jappan. Core level pphotoemission sppectroscoppy was carried out with Al K${\alpha}$ Line. The CdTe simiconductor was determined to be pp-typpe with low dopping concentration from Hall measurement. We found that there are two reacted pphases of Te with Eu (related to divalent Eu and trivalent Eu, resppectively) from least square fitting of Te 4d sppectra, but three is no indication of Cd reaction. Trivalent Eu exists after roughly one monolayer depposition (600 sec. depposition time is considered as one monolayer), which is also observed at Eu 3d core level sppectra. Overlayer Eu is metallized after roughly 2 monolayers depposition, as can be deduced from the fact that metallic edge near Fermi level begins to appear. The intensity of core-level of Te decreases expponentially at the initial stage (near one monolayer) and after one monolayer depposition it decreases more slowly due to Te out-diffusion. We categorized the growth mode of Eu on CdTe as S-K growth mode (cluster formation after one monolayer deppisition) from the relative intensity pplot of Te 4d normalized to the cleaved surface. At cleaved surface band bending is already established due to surface defects. At first 100 sec. depposition time the shift toward lower binding side by 0.6 eV is found at all core level sppectra of all elements in semiconductor. This shift is considered as the re-adjustment of surface Fermi level to the pposition induced by Eu metal (0.2 eV above the valence band maximum).

• Animal Systematics, Evolution and Diversity
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• v.11 no.1
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• pp.87-100
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• 1995

Fauna of medically important arthropods in Chindo Island was studied in July 1994. Among eight speices of mosquitoes (Diptera : Culicidae), Culex tritenirohyunchus was predomiant (46.5% of the total0, and Anopheles sinensis the next. Seven specimens of the unidentified Culex sp. which seemed to be new were also collected. Total 23 species of non-biting midges(Diptera : Chiornomidae) were found in Chindo Is. Of them , Chironomus kiiensis was the predominant species (67.3%) , and Ch.flaviplumus the next (15.6%). Three species, Cladopelma viridula, Dicrotendipes septemmaculatus and Harnischia urtilamellata are reported for the first time in Korea, and they are fully re-described with illustrations. Among five species of biting midges (Diptera : Ceraopogenidae) collected, Culicoides punctatus was predominant (88.7%). A species of Foreipomia was also collected, and this genus is not recorded in Korean fauna. Only two species of domiciliary cockroaches, Periplaneta japonica and P.americana were collected in small numbers and Blatella germanica which is known as the most predominant speices in Korea was not found. The predominant speices of field rodents was Apodemus agrarius and thier ectoparasites were Leptotrombidium orientale (Acarina : Tromicibulidae), Lxodes nipponensis (Acarina : Ixodidae) ; Laelaps jettmani and Eulaelaps stabularis (Acarina : Laelapidae).

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.2
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• pp.93-101
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• 2002

We have proposed and fabricated two lateral type field emission diodes, poly-Si emitter by utilizing the local oxidation of silicon (LOCOS) and GaN emitter using metal organic chemical vapor deposition (MOCVD) process. The fabricated poly-Si diode exhibited excellent electrical characteristics such as a very low turn-on voltage of 2 V and a high emission current of $300{\;}\bu\textrm{A}/tip$ at the anode-to-cathode voltage of 25 V. These superior field emission characteristics was speculated as a result of strong surface modification inducing a quasi-negative electron affinity and the increase of emitting sites due to local sharp protrusions by an appropriate activation treatment. In respect, two kinds of procedures were proposed for the fabrication of the lateral type GaN emitter: a selective etching method with electron cyclotron resonance-reactive ion etching (ECR-RIE) or a simple selective growth by utilizing $Si_3N_4$ film as a masking layer. The fabricated device using the ECR-RIE exhibited electrical characteristics such as a turn-on voltage of 35 V for $7\bu\textrm{m}$ gap and an emission current of~580 nA/l0tips at anode-to-cathode voltage of 100 V. These new field emission characteristics of GaN tips are believed to be due to a low electron affinity as well as the shorter inter-electrode distance. Compared to lateral type GaN field emission diode using ECR-RIE, re-grown GaN emitters shows sharper shape tips and shorter inter-electrode distance.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1597-1599
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• 2013

Since renal failure causes decrease in tumor marker excretion, use of these markers in cancer care and treatment in patients with renal insufficiency or hemodialysis is controversial. The aim of this study was to investigate differences of serum levels of tumor markers CA15-3, AFP, CA19-9 and CEA in patients with impaired renal function. A total of 100 patients referred to the Tabriz Immam Reza and Amiralmomenin hospital from June 2010 to November 2011 were selected for study. Subjects were divided to 3 groups of healthy, dialysis and renal failure but non hemodialysis cases, the last category being re-grouped based on creatinine clearance. No significant relationship between different groups in serum levels of CEA (P=0.99) and CA19-9 (P=0.29) tumor markers was found. A significant correlation was observed between serum levels of AFP (P<0.001) and CA15-3 (P<0.001) and also a tendency between creatinine clearance and CEA (r=0.05, P=0.625). Creatinine clearance significantly correlated with AFP (P<0.001, r=0.53) and CA15-3 (p=0.00, r=-0.412), but not CA19-9 (P=0.089, r=-0.171). According to results of this study it appears that use of tumor markers in patients with impaired renal function should be performed with special precautions.