• Food Science of Animal Resources
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• v.32 no.1
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• pp.103-111
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• 2012

This study was carried out to examine foodborne pathogenic contamination from 1,080 samples of cooked hams and sausages at 10 Korean processing facilities in 2010. The samples were collected from the six primary and additional sterilization products in same lot. To detect Salmonella spp., Staphylococcus aureus, Listeria monocytogenes and Clostridium perfringens in those products (n=1,080), the domestic standard method for Processing and Ingredients Specification of Livestock Products was used. As a result, Salmonella spp. was not detected in all 636 ham and 444 sausage samples. However, L. monocytogenes was detected in four (0.6%) ham and eight (1.8%) sausage samples from five manufactures. S. aureus was also only detected in 4 (0.6%) ham samples from two manufacturers, and C. perfringens was detected in 3 (0.5%) ham samples from three manufacturers, the contamination levels of these pathogens were less than 100 CFU/g. In conclusion, the results of this study indicate that the additional sterilization step of processing manufacturers could not assist to control the foodborne pathogenic bacteria.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.199-211
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• 2002

Digital substraction technique and computer-assisted densitometirc analysis detect minor change in bone density and thus increase the diagnostic accuracy. This advantage as well as high sensitivity and objectivity which precludes human bias have drawn interest in radiologic research area. The objectives of this study are to verify if Radiographic density can be recognized in linear pattern when density profile of standard periapical radiograph with the aluminium stepwedge as the reference, was investigated under varies circumstances which can be encountered in clinical situations, and in addition to that to obtain mutual relationship between the existing standard radiographic system, and future digital image systems, by confirming the corelationship between the standard radiograph and Digora system which is a digital image system currently being used. In order to make quantitative analysis of the bone tissue, digital image system which uses high resolution automatic slide scanner as an input device, and Digora system were compared and analyzed using multifunctional program, Brain3dsp. The following conclusions were obtained. 1. Under common clinical situation that is 70kVp, 0.2 sec., and focal distance 10cm, Al-Equivalent image equation was found to be Y=11.21X+46.62 $r^2=0.9898$ in standard radiographic system, and Y=12.68X+74.59, $r^2=0.9528$ in Digora system, and linear relation was confirmed in both the systems. 2. In standard radiographic system, when all conditions were maintained the same except for the condition of developing solution, Al-Equivalent image equation was Y=10.07X+41.64, $r^2=0.9861$ which shows high corelationship. 3. When all conditions were maintained the same except for the Kilovoltage peak, linear relationship was still maintained under 60kVp, and Al-Equivalent image equation was Y=14.60X+68.86, $r^2=0.9886$ in the standard radiograhic system, and Y=13.90X+80.68, $r^2=0.9238$ in Digora system. 4. When all conditions were maintained the same except for the exposure time which was varied from 0.01 sec. to 0.8 sec., Al-Equivalent image equation was found to be linear in both the standard radiographic system and Digora system. The R-square was distributed from 0.9188 to 0.9900, and in general, standard radiographic system showed higher R-square than Digora system. 5. When all conditions were maintained the same except for the focal distance which was varied from 5cm to 30cm, Al-Equivalent image equation was found to be linear in both the standard radiographic system and Digora system. The R-square was distributed from 0.9463 to 0.9925, and the standard radiographic system had the tendency to show higher R-square in shorter focal distances.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.239-240
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• 2008

As semiconductor devices are scaled down for better performance and more functionality, the Cu-based interconnects suffer from the increase of the resistivity of the Cu wires. The resistivity increase, which is attributed to the electron scattering from grain boundaries and interfaces, needs to be addressed in order to further scale down semiconductor devices [1]. The increase in the resistivity of the interconnect can be alleviated by increasing the grain size of electroplating (EP)-Cu or by modifying the Cu surface [1]. Another possible solution is to maximize the portion of the EP-Cu volume in the vias or damascene structures with the conformal diffusion barrier and seed layer by optimizing their deposition processes during Cu interconnect fabrication, which are currently ionized physical vapor deposition (IPVD)-based Ta/TaN bilayer and IPVD-Cu, respectively. The use of in-situ etching, during IPVD of the barrier or the seed layer, has been effective in enlarging the trench volume where the Cu is filled, resulting in improved reliability and performance of the Cu-based interconnect. However, the application of IPVD technology is expected to be limited eventually because of poor sidewall step coverage and the narrow top part of the damascene structures. Recently, Ru has been suggested as a diffusion barrier that is compatible with the direct plating of Cu [2-3]. A single-layer diffusion barrier for the direct plating of Cu is desirable to optimize the resistance of the Cu interconnects because it eliminates the Cu-seed layer. However, previous studies have shown that the Ru by itself is not a suitable diffusion barrier for Cu metallization [4-6]. Thus, the diffusion barrier performance of the Ru film should be improved in order for it to be successfully incorporated as a seed layer/barrier layer for the direct plating of Cu. The improvement of its barrier performance, by modifying the Ru microstructure from columnar to amorphous (by incorporating the N into Ru during PVD), has been previously reported [7]. Another approach for improving the barrier performance of the Ru film is to use Ru as a just seed layer and combine it with superior materials to function as a diffusion barrier against the Cu. A RulTaN bilayer prepared by PVD has recently been suggested as a seed layer/diffusion barrier for Cu. This bilayer was stable between the Cu and Si after annealing at $700^{\circ}C$ for I min [8]. Although these reports dealt with the possible applications of Ru for Cu metallization, cases where the Ru film was prepared by atomic layer deposition (ALD) have not been identified. These are important because of ALD's excellent conformality. In this study, a bilayer diffusion barrier of Ru/TaCN prepared by ALD was investigated. As the addition of the third element into the transition metal nitride disrupts the crystal lattice and leads to the formation of a stable ternary amorphous material, as indicated by Nicolet [9], ALD-TaCN is expected to improve the diffusion barrier performance of the ALD-Ru against Cu. Ru was deposited by a sequential supply of bis(ethylcyclopentadienyl)ruthenium [Ru$(EtCp)_2$] and $NH_3$plasma and TaCN by a sequential supply of $(NEt_2)_3Ta=Nbu^t$ (tert-butylimido-trisdiethylamido-tantalum, TBTDET) and $H_2$ plasma. Sheet resistance measurements, X-ray diffractometry (XRD), and Auger electron spectroscopy (AES) analysis showed that the bilayer diffusion barriers of ALD-Ru (12 nm)/ALD-TaCN (2 nm) and ALD-Ru (4nm)/ALD-TaCN (2 nm) prevented the Cu diffusion up to annealing temperatures of 600 and $550^{\circ}C$ for 30 min, respectively. This is found to be due to the excellent diffusion barrier performance of the ALD-TaCN film against the Cu, due to it having an amorphous structure. A 5-nm-thick ALD-TaCN film was even stable up to annealing at $650^{\circ}C$ between Cu and Si. Transmission electron microscopy (TEM) investigation combined with energy dispersive spectroscopy (EDS) analysis revealed that the ALD-Ru/ALD-TaCN diffusion barrier failed by the Cu diffusion through the bilayer into the Si substrate. This is due to the ALD-TaCN interlayer preventing the interfacial reaction between the Ru and Si.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.779-788
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• 2014

This study, as a case where the environmental conflict and dispute arose between the use and the conservation as in the other protected areas in Korea, took the first step to build ecological citizenship to solve various and complicated issues in a fundamental level by providing a basic information on differentiated environmental perceptions of the locality and the visitors of Seoraksan National Park. The questionnaire survey was employed on September 6th and 7th with 150 residents of the park area and 200 visitors of Osaek-Daechungbong trail. Total number of 13 survey questions was introduced using Dunlap and Liere's NEP index. The result shows that the perception of 'balance of nature' was more dominant to the perception of 'humans over nature' and the perception to the 'limits to growth' was also somewhat positive in both groups. The differences in environmental perceptions between the groups exist; the visitor group tended to have more positive level of acceptance of NEP views. Such differences in perceptions suggest that a different normative approach should be taken to the residents of the national park with less pro-environment in their perceptions when policy making. It thus seemed possible that ecological citizenship could be realized since the younger and the higher education level are, the more pro-environment. The findings of the research may cause some concerns however, because the study has been confined as a case study with basic understanding of environmental perceptions and its differences between the interest groups. More extensive research is required to confirm if this is generalized.

• Progress in Medical Physics
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• v.3 no.2
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• pp.1-12
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• 1992

For intraoperative radiation therapy using electron beams, a cone system to deliver a large dose to the tumor during surgical operation and to save the surrounding normal tissue should be developed and dosimetry for the cone system is necessary to find proper X-ray collimator setting as well as to get useful data for clinical use. We developed a docking type of a cone system consisting of two parts made of aluminum: holder and cone. The cones which range from 4cm to 9cm with 1cm step at 100cm SSD of photon beam are 28cm long circular tubular cylinders. The system has two 26cm long holders: one for the cones larger than or equal to 7cm diamter and another for the smaller ones than 7cm. On the side of the holder is an aperture for insertion of a lamp and mirror to observe treatment field. Depth dose curve. dose profile and output factor at dept of dose maximum. and dose distribution in water for each cone size were measured with a p-type silicone detector controlled by a linear scanner for several extra opening of X-ray collimators. For a combination of electron energy and cone size, the opening of the X-ray collimator was caused to the surface dose, depths of dose maximum and 80%, dose profile and output factor. The variation of the output factor was the most remarkable. The output factors of 9MeV electron, as an example, range from 0.637 to 1.549. The opening of X-ray collimators would cause the quantity of scattered electrons coming to the IORT cone system. which in turn would change the dose distribution as well as the output factor. Dosimetry for an IORT cone system is inevitable to minimize uncertainty in the clinical use.

• Journal of dental hygiene science
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• v.18 no.4
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• pp.252-264
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• 2018

The purpose of this study was to analyze the priorities of oral health education contents for preschool children by targeting teachers and parents using the Borich priority formula and The Locus for Focus Model. The survey was conducted in 212 teachers and 215 parents from December 26, 2017 to January 21, 2018. The priorities of oral health education contents were based on a 3-step analysis method, including the paired sample t-test, Borich priority formula, and The Locus for Focus Model. As a result of this study, the number of items about oral health education for preschool children that were prioritized by teachers was 7, while that by parents was 9. The top priorities that teachers and parents had in common were the following 5 items; "The progression of dental caries," "Symptoms of dental caries," "How to prevent dental caries," "Eruption sequence of permanent teeth," and "Method for emergency management of avulsed teeth." The teachers' priorities of the oral health education contents were the same between teachers and parents; "Eruption sequence of deciduous teeth" and "The function of the permanent teeth" were added. The parents' priorities of the oral health education contents were the same between teachers and parents; "The effect of fluoride application," "The number of permanent teeth," "How to prevent malocclusion," and "The appropriate timing of malocclusion treatment" were added. Based on the results of this study, when developing oral health education programs for teachers and parents, oral health education for teachers should include 7 items and oral health education for parents should include 9 items.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.547-558
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• 1997

Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majorities of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to hoot. In previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF. Understanding the mechanisms of TNF-resistance in TNF-$\alpha$ gene transfected cancer cells would be an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of new protective protein synthesis in the acquired resistance to TNF of TNF-$\alpha$ gene transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164, a murine fibrosarcoma cell line, using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF gene transfected cells(WEHI164-TNF) and the changes of TNF sensitivities after treatments with actinomycin D(transcription inhibitor) and cycloheximide ( translation inhibitor). Results : WEHI164 which was sensitive to TNF became resistant to TNF after being transfected with TNF-$\alpha$ gene and the resistance to TNF was partially reversed after treatment with actinomycin D, but not with cycloheximide. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ gene transfection may be associated with synthesis of some protective proteins.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.470-478
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• 1997

Background : Phagocytosis is probably the first step for mycobacteria to be virulent in host because virulent strains are more readily phagocytosed by macrophage than attenuated strains. According to the traditional concept, multi-drug resistant strains have been regarded as less virulent. However, this concept has been challenged, since recent studies(reported) showed that the degree of virulence and drug-resistance is not related. The purpose of this study is to evaluate whether the phagocytic activity of M.tuberculosis by peripheral blood mononuclear cells(PBMC) is different according to drug-resistance or host factor. To evaluate this, we estimated the difference of phagocytic activity of drug-resistant and drug-sensitive M.tuberculosis and also estimated the phagocytic activity of PBMC from intractable tuberculosis patients and healthy controls. Methods : PBMC from ten intractable tuberculosis patients and twelve healthy control, and three different strains of heat-killed M.tuberculosis, ie, ADS(all drug sensitive), MDR(multi-drug resistant), and ADR(all drug resistant) were used. After incubation of various strains of M.tuberculosis with PBMC, the phagocytic activity was evaluated by estimating proportion of PBMC which have phagocytosed M.tuberculosis. Results : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains(Percentage of PBMC phagocytosed M.tuberculosis in healthy control : ADS : $32.3{\pm}2.9%$, ADR : $49.6{\pm}3.4%$, p = 0.0022, Percentage of PBMC phagocytosed M.tuberculosis in intractable tuberculosis patients : ADS : $34.9{\pm}3.6%$, ADR : $50.7{\pm}4.5%$, p = 0.0069). However, there was no difference in phagocytic activity of PBMC from healthy control and intractable tuberculosis patients. Conclusion : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains and host factors does not seems to influence the phagocytosis of M.tuberculosis.

• Tuberculosis and Respiratory Diseases
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• v.44 no.6
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• pp.1353-1365
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• 1997

Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majority of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to host. In the previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF, and the probability was shown that the acquired resistance to TNF might be associated with synthesis of some protective protein. Understanding the mechanisms of TNF -resistance in TNF-$\alpha$ cDNA transfected cancer cells would be. an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of MnSOD, an antioxidant enzyme, in the acquired resistance to TNF of TNF-$\alpha$ cDN A transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164(murine fibrosarcoma cell line), NCI-H2058(human mesothelioma cell line), A549(human non-small cell lung cancer cell line), ME180(human cervix cancer cell line) cells using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF-$\alpha$ cDNA transfected cells(WEHI164-TNF, NCIH2058-TNF, A549-TNF, ME180-TNF) and the changes of MnSOD mRNA expressions with Northern blot analysis. Results : The MnSOD mRNA expressions of parental cells and genetically modified cells of WEHI164 and ME180 cells(both are naturally TNF sensitive) were not significantly different The MnSOD mRNA expressions of genetically modified cells of NCI-H2058 and A549(both are naturally TNF resistant) were higher than those of the parental cells, while those of parental cells with exogenous TNF were also elevated. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ cDNA transfection may not be associated with the change in the MnSOD expression, but the difference in natural TNF sensitivity of each cell may be associated with the level of the MnSOD expression.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.299-307
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• 2000

생물학적 동등성 시험은 동일 성분을 동량 함유한 제제가 유사조건에서 투여되었을 경우 그 유효성분이 전신순환혈이나 작용부위에서 유용하게 되는 속도 및 양에 큰 차이가 없음을 입증하는 시험이다. 즉 이미 제조허가 되어 시판중인 의약품과 동일한 품목의 제조허가를 받기 위한 경우이거나 생체이용률이 동일함을 증명하기 위해 실시하는 시험이다. 우리 나라에서는 1989년 1월 1일 이후 허가된 전문의약품으로서 신약과 동일한 의약품, 패취제제, 제제개선을 통해 흡수율을 높이는 경우에 생물학적 동등성 시험을 하도록 의무화하고 있다. 미국 FDA는 1975년 6월 생체이용률, 생물학적 동등성에 관한 규제안을 발표하였고, 우리 나라에서도 1988년 10월에 생물학적 동등성 시험 기준을 제정하였다. 유럽에서는 1991년 12월 CPMP(Committee for Proprietary Medicinal Products)에 의해 최초로 "생체이용률 및 생물학적 동등성에 대한 가이드라인"이 채택되었다. 그후 전문가 회의를 거쳐 규정 전반에 관한 것과 일반적 항목에 대한 검토가 이루어져 최종 개정된 가이드라인이 만들어졌다. 현재 in vivo 생체 이용률을 비교하는 생물학적 동등성 시험의 중요성이 증대되고 있고, 국제적으로도 각 국가별 생물학적 동등성 시험의 평가방법이나 기준설정에 대한 연구가 다양하게 이루어지고 있다. 또한 ICH에서도 생물학적 동등성 시험의 국제적 조화를 위한 시도가 이루어지고 있다. 우리 나라의 현행 생물학적 동등성 기준은 1998년 개정된 것을 사용하고 있으나 국제적 발전 추세에 맞추어 기준의 제고를 모색하고 있다. 그 일환으로 유럽의 "의약품의 생체이용률 및 생물학적 동등성 시험 가이드라인"을 소개하고자 한다., globunlin II의 두 component로 분리(分離)되었고 oryzenin은 시료(試料) 육우(陸羽) 132호(號), 등판(藤坂) 5호(號), 관산(關山) 재건(再建)에서는 oryzenin I, oryzenin II, oryzenin III의 3 component를 분리(分離)하였고 팔달(八達), 진흥(振興), 서광(瑞光), 은방주(銀坊主), 다마금(多摩錦), Pin Galw56의 6시료(試料)에서는 oryzenin II, oryzenin III의 2 component만 분리(分離)하였다. 3. 각(各) fraction을 여지전기영동(濾紙電氣泳動)하여 각(各) component의 농도곡선(濃度曲線)에 의해 함량(含量)을 구(求)한 결과(結果) albumin 0.26%, globulin I, 0.35%, globulin II, 0.32%, prolamin, 0.41%, oryzenin I, 0.30%, oryzenin II, 2.23%, oryzenin III, 2.66%이었다.미국의 경우 3일 이내 전화나 FAX로 보고하고, 10일이내 문서로써 보고하도록 되어 있다. 이러한 임상적 안전성 자료 관리에 대한 신속 보고 정의 및 기준에 대해서는 ICH에서도 논의가 되어 Step 4까지 다다르고 있으므로 앞으로 각 국에서의 적용만 남아있는 상태이고 보면 신약의 개발과 더불어 임상시험에서의 부작용등의 안전성 자료 관리에 대한 중요성은 더욱 강조될 것이다.공하는 음식의 섭취정도에도 영향을 주고 있으므로 학생들에게 학부모와 전담교사 및 학교영양사는 학생들에게 이상적인 아침식사에 대한 교육은 물론이고 아침식사를 실천할 수 있도록 다양한 방안에 대해 함께 연구해야 하겠다. 정부차원에서 학교급식에 아침식사 프로그램을 도입할