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The Neuroprotective Effects of 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX) Via Mediation of Nitric Oxide Synthase on Hypoxic-ischemic Brain Injury in Neonatal Rats

  • Jung, Ji-Eun;Keum, Kyung-Hae;Choi, Eun-Jin;Kim, Jin-Kyung;Chung, Hai-Lee;Kim, Woo-Taek
    • Neonatal Medicine
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    • v.18 no.1
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    • pp.59-69
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    • 2011
  • Purpose: Current studies have demonstrated the neuroprotective effects of 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX) in many animal models of brain injury, including hypoxic-ischemic (HI) encephlopathy, trauma and excitotoxicity, but limited data are available for those during the neonatal periods. Here we investigated whether CNQX can protect the developing rat brain from HI injury via mediation of nitric oxide synthase. Methods: In an in vivo model, left carotid artery ligation was done in 7-day-old Sprague-Dawley (SD) rat pups. The animals were divided into six groups; normoxia (N), hypoxia (H), hypoxia with sham-operation (HS), hypoxia with operation (HO), HO treated with vehicle (HV), and HO treated with CNQX at a dose of 10 mg/kg (HC). Hypoxia was made by exposure to a 2 hr period in the hypoxic chamber (92% $N_2$, 8% $O_2$). In an in vitro model, embryonic cortical neuronal cell culture of SD rats at 18-day gestation was done. The cultured cells were divided into three groups: normoxia (N), hypoxia (H), and hypoxia treated with CNQX (HC). The N group was prepared in 5% $CO_2$ incubators and the other groups were placed in 1% $O_2$) incubators (94% $N_2$, 5% $CO_2$) for 16 hr. Results: In the in vitvo and in vivo models, the expressions of iNOS and eNOS were reduced in the hypoxia group when compared to the normoxia group, whereas they were increased in the CNQX-treated group compared to the hypoxia group. In contrast, the expression of nNOS was showed reversely. Conclusion: CNQX has neuroprotective property over perinatal HI brain injury via mediation of nitric oxide synthase.

Developing Measurement Tool of Entrepreneurship for Young Entrepreneurs (청년 창업자를 위한 창업역량 측정도구 개발)

  • Lee, Ji An;Ahn, Young Sik
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.4
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    • pp.197-209
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    • 2018
  • Recently, many start-up failures occur as the number of attempts to start a business increases in a social atmosphere that encourages start-up. In particular, young entrepreneurs have a lower survival rate than general entrepreneurs because young entrepreneurs are challenging just with a simple idea to overcome the difficulties of employment while lacking prior knowledge and experience of business. Therefore, the reason for the failure of start-up is lack of preparation for start-up and lack of entrepreneurship. The purpose of this study is to develop a measurement tool to build a basic framework for entrepreneurship development and start - up preparation activities for young people. To develop an entrepreneurship measurement tool, researchers developed a preliminary question through qualitative research methods such as literature research, focus group interview, and expert verification. After that, researchers surveyed 102 entrepreneurs using quantitative research method and to verify the construct validity of the measurement tool, the final entrepreneurship measurement tool was completed through exploratory factor analysis and confirmatory factor analysis. The entrepreneurship measurement tool developed through this research process consists of 7 components and 15 measurement items. First, in the step of 'confirming entrepreneurial intention', two items of 'self-analytic competence', three items of 'ability of establishing start-up philosophy'are contained. Second, in the step of 'drawing up a start-up model', two items are contained in each category such as, 'ability of eliciting entrepreneurial idea,' 'ability of analyzing idea validity,' 'competence of planning a venture start-up model'. Third, in the step of 'planning the venture start-up,' two items are contained in each category such as, 'business-plan presentation competency,' 'ability of implementing organizational system.'. The measurement tool of entrepreneurship is meaningful as it could help young entrepreneur find out their lacking competence in preparing their start-ups and strengthen necessary competences by measuring their own entrepreneurship. Rather in the entrepreneurship education, basic data that can diagnose the entrepreneurship of young entrepreneurs is provided.

Development of 2.5D Electron Dose Calculation Algorithm (2.5D 전자선 선량계산 알고리즘 개발)

  • 조병철;고영은;오도훈;배훈식
    • Progress in Medical Physics
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    • v.10 no.3
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    • pp.133-140
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    • 1999
  • In this paper, as a preliminary study for developing a full 3D electron dose calculation algorithm, We developed 2.5D electron dose calculation algorithm by extending 2D pencil-beam model to consider three dimensional geometry such as air-gap and obliquity appropriately. The dose calculation algorithm was implemented using the IDL5.2(Research Systems Inc., USA), For calculation of the Hogstrom's pencil-beam algorithm, the measured data of the central-axis depth-dose for 12 MeV(Siemens M6740) and the linear stopping power and the linear scattering power of water and air from ICRU report 35 was used. To evaluate the accuracy of the implemented program, we compared the calculated dose distribution with the film measurements in the three situations; the normal incident beam, the 45$^{\circ}$ oblique incident beam, and the beam incident on the pit-shaped phantom. As results, about 120 seconds had been required on the PC (Pentium III 450MHz) to calculate dose distribution of a single beam. It needs some optimizing methods to speed up the dose calculation. For the accuracy of dose calculation, in the case of the normal incident beam of the regular and irregular shaped field, at the rapid dose gradient region of penumbra, the errors were within $\pm$3 mm and the dose profiles were agreed within 5%. However, the discrepancy between the calculation and the measurement were about 10% for the oblique incident beam and the beam incident on the pit-shaped phantom. In conclusions, we expended 2D pencil-beam algorithm to take into account the three dimensional geometry of the patient. And also, as well as the dose calculation of irregular field, the irregular shaped body contour and the air-gap could be considered appropriately in the implemented program. In the near future, the more accurate algorithm will be implemented considering inhomogeneity correction using CT, and at that time, the program can be used as a tool for educational and research purpose. This study was supported by a grant (#HMP-98-G-1-016) of the HAN(Highly Advanced National) Project, Ministry of Health & Welfare, R.O.K.

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Wildfire Severity Mapping Using Sentinel Satellite Data Based on Machine Learning Approaches (Sentinel 위성영상과 기계학습을 이용한 국내산불 피해강도 탐지)

  • Sim, Seongmun;Kim, Woohyeok;Lee, Jaese;Kang, Yoojin;Im, Jungho;Kwon, Chunguen;Kim, Sungyong
    • Korean Journal of Remote Sensing
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    • v.36 no.5_3
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    • pp.1109-1123
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    • 2020
  • In South Korea with forest as a major land cover class (over 60% of the country), many wildfires occur every year. Wildfires weaken the shear strength of the soil, forming a layer of soil that is vulnerable to landslides. It is important to identify the severity of a wildfire as well as the burned area to sustainably manage the forest. Although satellite remote sensing has been widely used to map wildfire severity, it is often difficult to determine the severity using only the temporal change of satellite-derived indices such as Normalized Difference Vegetation Index (NDVI) and Normalized Burn Ratio (NBR). In this study, we proposed an approach for determining wildfire severity based on machine learning through the synergistic use of Sentinel-1A Synthetic Aperture Radar-C data and Sentinel-2A Multi Spectral Instrument data. Three wildfire cases-Samcheok in May 2017, Gangreung·Donghae in April 2019, and Gosung·Sokcho in April 2019-were used for developing wildfire severity mapping models with three machine learning algorithms (i.e., Random Forest, Logistic Regression, and Support Vector Machine). The results showed that the random forest model yielded the best performance, resulting in an overall accuracy of 82.3%. The cross-site validation to examine the spatiotemporal transferability of the machine learning models showed that the models were highly sensitive to temporal differences between the training and validation sites, especially in the early growing season. This implies that a more robust model with high spatiotemporal transferability can be developed when more wildfire cases with different seasons and areas are added in the future.

Neuroprotection of Recombinant Human Erythropoietin Via Modulation of N-methyl-D-aspartate Receptors in Neonatal Rats with Hypoxic-ischemic Brain Injury (신생 백서의 저산소성 허혈성 뇌손상에서 NMDA receptor 조절을 통한 유전자 재조합 인 에리스로포이에틴의 신경보호)

  • Jang, Yoon-Jung;Seo, Eok-Su;Kim, Woo-Taek
    • Neonatal Medicine
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    • v.16 no.2
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    • pp.221-233
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    • 2009
  • Purpose: Erythropoietin (EPO) has neuroprotective effects in many animal models of brain injury, including hypoxic-ischemic (HI) encephalopathy, trauma, and excitotoxicity. Current studies have demonstrated the neuroprotective effects of EPO, but limited data are available for the neonatal periods. Here in we investigated whether recombinant human EPO (rHuEPO) can protect the developing rat brain from HI injury via modulation of NMDA receptors. Methods: In an in vitro model, embryonic cortical neuronal cell cultures from Sprague-Dawley (SD) rats at 19-days gestation were established. The cultured cells were divided into five groups: normoxia (N), hypoxia (H), and 1, 10, and 100 IU/mL rHuEPO-treated (H+E1, H+ E10, and H+E100) groups. To estimate cell viability and growth, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was done. In an in vivo model, left carotid artery ligation was performed on 7-day-old SD rat pups. The animals were divided into six groups; normoxia control (NC), normoxia Sham-operated (NS), hypoxia-ischemia only (H), hypoxia-ischemia+vehicle (HV), hypoxia-ischemia+rHuEPO before a HI injury (HE-B), and hypoxia-ischemia+rHuEPO after a HI injury (HE-A). The morphologic changes following brain injuries were noted using hematoxylin and eosin (H/E) staining. Real-time PCR using primers of subunits of NMDA receptors (NR1, NR2A, NR2B, NR2C and NR2D) mRNA were performed. Results: Cell viability in the H group was decreased to less than 60% of that in the N group. In the H+E1 and H+E10 groups, cell viability was increased to >80% of the N group, but cell viability in the H+E100 group did not recover. The percentage of the left hemisphere area compared the to the right hemisphere area were 98.9% in the NC group, 99.1% in the NS group, 57.1% in the H group, 57.0% in the HV group, 87.6% in the HE-B group, and 91.6% in the HE-A group. Real-time PCR analysis of the expressions of subunits of NMDA receptors mRNAs in the in vitro and in vivo neonatal HI brain injuries generally revealed that the expression in the H group was decreased compared to the N group and the expressions in the rHuEPO-treated groups was increased compared to the H group. Conclusion: rHuEPO has neuroprotective property in perinatal HI brain injury via modulation of N-methyl-D-aspartate receptors.

Techniques for Acquisition of Moving Object Location in LBS (위치기반 서비스(LBS)를 위한 이동체 위치획득 기법)

  • Min, Gyeong-Uk;Jo, Dae-Su
    • The KIPS Transactions:PartD
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    • v.10D no.6
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    • pp.885-896
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    • 2003
  • The typws of service using location Information are being various and extending their domain as wireless internet tochnology is developing and its application par is widespread, so it is prospected that LBS(Location-Based Services) will be killer application in wireless internet services. This location information is basic and high value-added information, and this information services make prior GIS(Geographic Information System) to be useful to anybody. The acquisition of this location information from moving object is very important part in LBS. Also the interfacing of acquisition of moving object between MODB and telecommunication network is being very important function in LBS. After this, when LBS are familiar to everybody, we can predict that LBS system load is so heavy for the acquisition of so many subscribers and vehicles. That is to say, LBS platform performance is fallen off because of overhead increment of acquiring moving object between MODB and wireless telecommunication network. So, to make stable of LBS platform, in this MODB system, acquisition of moving object location par as reducing the number of acquisition of unneccessary moving object location. We study problems in acquiring a huge number of moving objects location and design some acquisition model using past moving patternof each object to reduce telecommunication overhead. And after implementation these models, we estimate performance of each model.

GIS based Development of Module and Algorithm for Automatic Catchment Delineation Using Korean Reach File (GIS 기반의 하천망분석도 집수구역 자동 분할을 위한 알고리듬 및 모듈 개발)

  • PARK, Yong-Gil;KIM, Kye-Hyun;YOO, Jae-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.20 no.4
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    • pp.126-138
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    • 2017
  • Recently, the national interest in environment is increasing and for dealing with water environment-related issues swiftly and accurately, the demand to facilitate the analysis of water environment data using a GIS is growing. To meet such growing demands, a spatial network data-based stream network analysis map(Korean Reach File; KRF) supporting spatial analysis of water environment data was developed and is being provided. However, there is a difficulty in delineating catchment areas, which are the basis of supplying spatial data including relevant information frequently required by the users such as establishing remediation measures against water pollution accidents. Therefore, in this study, the development of a computer program was made. The development process included steps such as designing a delineation method, and developing an algorithm and modules. DEM(Digital Elevation Model) and FDR(Flow Direction) were used as the major data to automatically delineate catchment areas. The algorithm for the delineation of catchment areas was developed through three stages; catchment area grid extraction, boundary point extraction, and boundary line division. Also, an add-in catchment area delineation module, based on ArcGIS from ESRI, was developed in the consideration of productivity and utility of the program. Using the developed program, the catchment areas were delineated and they were compared to the catchment areas currently used by the government. The results showed that the catchment areas were delineated efficiently using the digital elevation data. Especially, in the regions with clear topographical slopes, they were delineated accurately and swiftly. Although in some regions with flat fields of paddles and downtowns or well-organized drainage facilities, the catchment areas were not segmented accurately, the program definitely reduce the processing time to delineate existing catchment areas. In the future, more efforts should be made to enhance current algorithm to facilitate the use of the higher precision of digital elevation data, and furthermore reducing the calculation time for processing large data volume.

Establishment of the expression system of human HtrA2 in the zebrafish (Zebrafish 동물모델에서 human HtrA2의 expression system 정립에 관한 연구)

  • Cho, Sung-Won;Park, Hyo-Jin;Kim, Goo-Young;Nam, Min-Kyung;Kim, Ho-Young;Ko, In-Ho;Kim, Cheol-Hee;Rhim, Hyang-Shuk
    • Journal of Life Science
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    • v.16 no.4
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    • pp.571-578
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    • 2006
  • HtrA2/Omi, a mitochondrial trypsin-like serine protease, is pivotal in regulating apoptotic cell death. Several lines of recent evidence suggest that HtrA2 is associated with the pathogenesis of neurodegenerative disorders; however, the physiological function of HtrA2 still remains elusive. For studying physiological function of HtrA2 in depth, it is necessary to develop a suitable expression system in the model animal. We therefore utilized the zebrafish as a model animal to establish expression of human HtrA2 (hHtrA2) in vivo. For expression of mature HtrA2 as GFP fusion in zebrafish embryos, the HtrA2 (WT) or (S306A) cDNAs with the C-terminal GFP tag were inserted into the pCS2+ plasmid. Expression patterns of HtrA2 in HEK293 cells were first monitored by immunofluorescence staining and immunoblot assays, showing approximately 64 kDa of the HtrA2-GFP fusion proteins. Subsequently, the hHtrA2 plasmid DNA or in vitro transcribed mRNA was microinjected into zebrafish embryos. The expression patterns of HtrA2 in Zebrafish embryos were monitored by GFP fluorescence in 24 hours-post-fertilization (hpf). Although expression patterns of HtrA2-GFP in developing embryos were different between the injected DNA and mRNA, both nucleic acids revealed good expression levels to further study the physiological role of HtrA2 in vivo. This study provides a suitable condition for expressing hHtrA2 in the zebrafish embryos as well as a method for generating useful system to investigate physiological properties of the specific human genes.

A Study on Experimental Construction of Community Garden - A Case Study on Rooftop of SAHA Disabled Welfare House - (커뮤니티 가든 조성을 위한 실험 연구 - 사하 장애인복지관 옥상을 대상으로 -)

  • Kim, Seung-Hwan;Yoon, Sung-Yung;Cha, Min-Jun;Yoo, yeon-seo;Cho, Ji-Young;Kim, Yoon-Sun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.2
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    • pp.24-37
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    • 2012
  • In this study, Community Garden of various national and international practices trends to an advanced research, the concept of community garden participated with a group operation out of initiative to produce safety food while securing space for the community, ensuring the area that has gone through a new form of active secure urban green space plan, urban renewal movement was defined as the mean. Furthermore, for the purpose of improving the poor welfare environment by attempting to experimentally make a community garden of a disabled welfare house rooftop and how to target its planning and construction process, partnership involvement, business processes have been investigated, such as cost sharing. The whole process including a budget for development of this case was conducted by the Busan Green Trust. Standard Chartered (SC) First Bank's 50% fund share by community chest, participation of volunteers, support of Busan City and Saba-gu, outside of that, sharing parts or trial to participate by diverse partnership of enterprise, public corporation and laboratory, these are the key in developing community garden's model. Established community garden places resulted food production to users of welfare center for the disabled, participating urban agricultural experience program, horticultural therapy, complex community chapter and cultural center. Furthermore, we could find the meaning of rooftop community garden in the point that it is a low cost garden by applying movable and unmovable planters. This study is profitable for improving urban environment, ensuring community chapter and urban green areas, regenerating a city to develop experimental community garden model by using a welfare house rooftop.

Buyers' Trust in a Brand and Brand Loyalty in the business-to-business (산업재 시장에서 브랜드 신뢰와 브랜드 충성도에 관한 연구)

  • Han, Sang-Rin;Sung, Hyung-Suk
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.11a
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    • pp.29-51
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    • 2005
  • Brands are important in the consumer market. They are the interface between consumers and the company, consumers may develop loyalty to brands. also, The late development of industrial marketing explains the near absence of research on Brand Equity in business to business. With recent change, industrial companies have shifted from a production focus to a customer focus. industrial brand is fast developing. The basic purpose of this study is to investigate industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers. Factors hypothesized to influence trust in a brand include a number of brand characteristics, company characteristics and consumer-brand characteristics. This research presented a comprehensive constructive model consisting of components of industrial brand trust and loyalty, and then propose the research model base on prior researches and studies about relationships among components of industrial brand loyalty. Data were gathered from respondents who work in industrial buying center. For this study, Data were analyzed by SPSS 10.0 and AMOS 4.0. The results of this research analysis were as fallow. Industrial brand trust and loyalty were positively related with a number of industrial brand characteristics, supplier characteristics and buyer-brand characteristics. relationship commitment. This research newly proposed the concept of 'industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers'

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