• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.278-286
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• 2022

Live bacterial vector vaccines are one of the most promising vaccine types and have the advantages of low cost, flexibility, and good safety. Meanwhile, protein secretion systems have been reported as useful tools to facilitate the release of heterologous antigen proteins from bacterial vectors. The twin-arginine translocation (Tat) system is an important protein export system that transports fully folded proteins in a signal peptide-dependent manner. In this study, we constructed a live vector vaccine using an engineered commensal Escherichia coli strain in which amiA and amiC genes were deleted, resulting in a leaky outer membrane that allows the release of periplasmic proteins to the extracellular environment. The protective antigen proteins SLY, enolase, and Sbp against Streptococcus suis were targeted to the Tat pathway by fusing a Tat signal peptide. Our results showed that by exploiting the Tat pathway and the outer membrane-defective E. coli strain, the antigen proteins were successfully secreted. The strains secreting the antigen proteins were used to vaccinate mice. After S. suis challenge, the vaccinated group showed significantly higher survival and milder clinical symptoms compared with the vector group. Further analysis showed that the mice in the vaccinated group had lower burdens of bacteria load and slighter pathological changes. Our study reports a novel live bacterial vector vaccine that uses the Tat system and provides a new alternative for developing S. suis vaccine.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.14-17
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• 2005

Global latent heat flux data sets are crucial for many studies such as those related to air-sea interaction and climate variation. Currently, various global latent heat flux data sets are constructed using satellite data. Japanese Ocean Flux data sets with Use of Remote sensing Observations (J-OFURO) includes one of the satellite-derived global latent heat flux data (Kubota et aI., 2000). In this study, we review future development of J-OFURO global latent heat flux data set. In particular, we investigate usage of multi-satellite data for estimating accurate global latent heat flux. Accurate estimation of surface wind speeds over the global ocean is one of key factors for the improved estimation of global latent heat flux. First, we demonstrate improvement of daily wind speed estimation using multi-satellites data from microwave radiometers and scatterometers such as DMSP/SSMI, ERS/AMI, QuikSCAT/SeaWinds, AqualAMSR-E, ADEOS2/AMSR etc. Next, we demonstrate improvement of global latent heat flux estimation using the wind speed data derived from multi-satellite data.

• Electronics and Telecommunications Trends
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• v.20 no.3 s.93
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• pp.10-18
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• 2005

최근 들어 차량은 단순한 교통수단으로서의 고립 공간이 아니라 유무선 통신망과 초고속 인터넷으로 세상 모든 정보와 연결되고 그 안에서 다양한 정보 활동이 가능한 소위 제3의 디지털 라이프 공간으로 발전하고 있다. 세계적인 텔레매틱스 기술 개발과 표준화 추세는 첨단 IT 강국인 국내에서 IT839 전략에 힘입어 더욱 더 가속도를 더해가고있다. ETRI, TTA, 그리고 텔레매틱스 표준화 포럼으로 대표되는 표준 개발 주체들은상호 유기적인 관계 하에 산업계에서 필요로 하는 핵심 기술표준개발 작업을 진행중이며 세계적으로도 OSGi, AMI-C, ERTICO 등을 비롯한 산업계 표준 단체들의 표준화 활동이 활발히 전개되고 있다. 본 고에서는 이러한 국내외 표준화 현황을 살펴보고 향후의 텔레매틱스 표준화 전략에 대해서 고찰해 보기로 한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.446-449
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• 2009

In this paper, we present a novel method for reconstructing a super-resolution image using multi-view low-resolution images captured for depth varying scene without requiring complex analysis such as depth estimation and feature matching. The proposed method is based on the iterative back projection technique that is extended to the 3D volume domain (i.e., space + depth), unlike the conventional superresolution methods that handle only 2D translation among captured images.

• Imaging Science in Dentistry
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• v.54 no.3
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• pp.276-282
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• 2024

Purpose: This study aimed to assess the performance of 2-dimensional (2D) imaging with microscopy coils in delineating teeth and periodontal tissues compared with conventional 3-dimensional(3D) imaging on a 3 T magnetic resonance imaging (MRI) unit. Materials and Methods: Twelve healthy participants (4 men and 8 women; mean age: 25.6 years; range: 20-52 years) with no dental symptoms were included. The left mandibular first molars and surrounding periodontal tissues were examined using the following 2 sequences: 2D proton density-weighted (PDw) images and 3D enhanced T1 high-resolution isotropic volume excitation (eTHRIVE) images. Two-dimensional MRI images were taken using a 3 T MRI unit and a 47 mm microscopy coil, while 3D MRI imaging used a 3 T MRI unit and head-neck coil. Oral radiologists assessed dental and periodontal structures using a 4-point Likert scale. Inter- and intra-observer agreement was determined using the weighted kappa coefficient. The Wilcoxon signed-rank test was used to compare 2D-PDw and 3D-eTHRIVE images. Results: Qualitative analysis showed significantly better visualization scores for 2D-PDw imaging than for 3D-eTHRIVE imaging (Wilcoxon signed-rank test). 2D-PDw images provided improved visibility of the tooth, root dental pulp, periodontal ligament, lamina dura, coronal dental pulp, gingiva, and nutrient tract. Inter-observer reliability ranged from moderate agreement to almost perfect agreement, and intra-observer agreement was in a similar range. Conclusion: Two-dimensional-PDw images acquired using a 3 T MRI unit and microscopy coil effectively visualized nearly all aspects of teeth and periodontal tissues.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.196-200
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• 2005

In this work, we investigated simple Aㅣ/TCO/a-Si:H(n)/c-Si(p)/Al hetero-junction solar cells prepared by low temperature processes, unlike conventional thermal diffused c-Si solar cells. a-Si:H/c-Si hetero-junction solar cells are processed by low temperature deposition of n-type hydrogenated amorphous silicon (a-Si:H) films by plasma-enhanced chemical vapor deposition on textured and flat p-type silicon substrate. A detailed investigation was carried out to acquire optimization and compatibility of amorphous layer, TCO (ZnO:Al) layer depositions by changing the plasma process parameters. As front TCO and back contact, ZnO:Al and AI were deposited by rf magnetron sputtering and e-beam evaporation, respectively. The photovoltaic conversion efficiency under AMI.5 and the quantum efficiency on $1cm^2$ sample have been reported. An efficiency of $12.5\%$ is achieved on hetero-structure solar cells based on p-type crystalline silicon.

• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.321-329
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• 2006

The use of tapered structural members was first proposed by Ami rikian for the economical use of materials.Generaly, tapered members are used in single-story structures with one or more bays and in cantilevered sections of ate architectural representation. If only focused on the section performance, however, the width-to-thickness ratio or t apered ratio can exced regulations. Such a case requires a study on the behavior of tapered members. To investigate the plastic and local buckling behavior of web-tapered beams, seven steel beams were the tapered ratio and the width-to-thicknes ratio. The results of maximum strength, strength deterioration, and stiffnes deterioration were compared.

• Archives of Pharmacal Research
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• v.23 no.2
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• pp.128-138
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• 2000

In continuation of the previous work (Fathalla, 1992) on the synthesis of some heterocycles containing uracil moiety, we report herein the incorporation of uracil moiety into cyan-opyridine thione, thiosemecarbazone, semicarbazone, cyanopyridine, ami nocyano pyridine, isoxazoline, pyrazoline, pyrimidine, triazolo pyrimidine, pyran, selena and thiazole derivatives which might modify their biological activities. The biological studies revealed that the chemical compound III f showed high molluscicdal activity than other compounds. The profile of the nucleoprotein extracted from chemically (compound IIIc, e, f and g) treated or UV-irradiated B.alexandrina snails did not show appreciable differences when compared to non-treated (native) snails by using SDS-PAGE, where no obvious qualitative or quantitative differences were observed. Immunization of experimental animals with the nucleoprotein extracted from native, chemically (compound III f ＆ g) treated or physically treated B.alexandrina snails induced significant protection against challenge with normal S.mansoni cercariae, as compared to the non-immunized challenged control. As well as , a decrease in the number of granuloma formation and the size range of granuloma was also observed in immunized animals. It is concluded that, compounds III f and g have a potent molluscicidal activity. They also induced chemical modification comparable to that induced by physical treatment in the snail's nucleoprotein, which could possibly be used in immunization against S. mansoni infection.

• Journal of the Korean Institute of Gas
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• v.23 no.5
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• pp.8-14
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• 2019

Although the rate of city gas supply in South Korea has grown significantly, the fields related to gas meters have not yet escaped from the initial method of service (e.g. measurement, safety checks, billing, etc). As smart gas meters are actively developed and researched, the introduction of smart gas meters requires rational performance evaluation methods and standards to verify reliability and safety. The purpose of this paper is to make a prototype of the performance evaluation to test the performance of the smart gas meter and to derive the performance evaluation method by conducting the demonstration operation so that the smart gas meter can be smoothly distributed in South Korea.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.334-339
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• 2000

The considerable researches have been done on the change,1 associated with age in the blood picture of domestic animals, but a survey has not been of the blood picture in Thoroughbred fears in Korea. Therefore, the purpose of this study is to outline the range of values in clinically not\\\\`- mal Thoroughbred foals. Some blood chemical parameters from 3 days to 8 weeks of age were exam-ined to obtain normal values in Thoroughbred foal7. Blood samples were obtained from the jugular vein in 11 Thoroughbred foals and collected at 3 days, and at 1,2,4 and 8 weeks of age, respectively. The results obtained ill this study were summarized as follows: The packed cell volume (PCV) at 4 weeks of age was significantly lower than that at 3 days of age (P<0.01) and that al 2 and 8 weeks of age were straightly lower than that at 3 days of age (P<0.05). The total protein (TP) at 8 weeks of age was higher than that at 3 days, 1 and 2 weeks of age (P<0.05). The activity of aspartate ami-notransferase (AST) at 2,4 and 8 weeks of age were significantly higher than that at 3 days of age (P<0.01). The total bilirnbin showed a tendency to decrease gradually according to the weeks and that at 2,4 and 8 weeks of age were significantly lower than that at 3 days of age (P<0.01). The BUN at 1 and 8 weeks of ago were lower than that at 3 days of age (P<0.05). The concentration of Ca at 1 week of alee was higher than that at 3 days of age (P<0.05). The vitamin A and vitamin E showed a tendency to decrease gradually from 3 days to 4 weeks of age and increased slightly at 8 weeks of age.