• Title/Summary/Keyword: frequency-response

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2,4-Dinitrochlorobenzene-induced Atopic Dermatitis Like Immune Alteration in Mice (마우스에서 2,4-Dinitrochlorobenzene을 이용한 아토피성 피부염 발현 관련 면역지표치 분석)

  • Lee, Seung-Hye;Baek, Seong-Jin;Kim, Hyoung-Ah;Heo, Yong
    • Toxicological Research
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    • v.22 no.4
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    • pp.357-364
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    • 2006
  • This study was undertaken to develop a reliable mice model demonstrating similar immunologic phenomena as human atopic dermatitis characterized with predominance of type-2 immune response. BALB/C mice and NC/Nga mice were sensitized twice with $100{\mu}l$ of 1% 2,4-dinitrochlorobenzene (DNCB) or vehicle (acetone : olive oil=4:1 mixture) in a week and challenged twice with $100{\mu}l$ of 0.2% DNCB or the vehicle at the following week. Mice were sacrificed at 19 days following the second DNCB or vehicle challenge for NC/Nga mice and at 28 days following the second DNCB or vehicle challenge for BALB/c mice. Upregulation of plasma 1gE, a hallmark of atopic dermatitis occurrence, was evident in the plasma obtained 4 day after the second DNCB challenge from BALB/c mice (approximately 4-fold) and NC/Nga mice (approximately 6-fold) treated with DNCB in comparison with that of the vehicle treated-control mice, and remain higher $3{\sim}4$ week after the second challenge. Ratio of plasma IgG1 versus IgG2a concentration was significantly higher in the mice treated with DNCB than the control mice, which also implies the skewed type-2 reactivity in vivo. Ratio of interleukin-4 versus interferon gamma produced in the splenic T cell culture supernatants was approximately 3-fold higher in the both strains of mice treated with DNCB than their control mice, respectively. The DNCB-treated mice demonstrated atopic dermatitis-like skin legions characterized with erythma, scaling, and hemorrhage, which was not observed with the control mice. Scratching on face or dorsal area was significantly more frequent (approximately 25-fold) in the DNCB-treated mice than the control at next day of the second DNCB challenge, and scratching frequency remains higher (approximately 4-fold) in the mice treated with DNCB than the control at 14 day following the second DNCB challenge. Overall, the mice model developed through sensitization and challenge with DNCB may be useful for research on atopic dermatitis and development of treatment materials for atopic dermatitis.

An Evaluation Method of X-ray Imaging System Resolution for Non-Engineers (비공학도를 위한 X-ray 영상촬영 시스템 해상력 평가 방법)

  • Woo, Jung-Eun;Lee, Yong-Geum;Bae, Seok-Hwan;Kim, Yong-Gwon
    • Journal of radiological science and technology
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    • v.35 no.4
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    • pp.309-314
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    • 2012
  • Nowadays, digital Radiography (DR) systems are widely used in clinical sites and substitute the analog-film x-ray imaging systems. The resolution of DR images depends on several factors such as characteristic contrast and motion of the object, the focal spot size and the quality of x-ray beam, x-ray scattering, the performance of the DR detector (x-ray conversion efficiency, the intrinsic resolution). The DR detector is composed of an x-ray capturing element, a coupling element and a collecting element, which systematically affect the system resolution. Generally speaking, the resolution of a medical imaging system is the discrimination ability of anatomical structures. Modulation transfer function (MTF) is widely used for the quantification of the resolution performance for an imaging system. MTF is defined as the frequency response of the imaging system to the input of a point spread function and can be obtained by doing Fourier transform of a line spread function, which is extracted from a test image. In clinic, radiologic technologists, who are in charge of system maintenance and quality control, have to evaluate or make routine check on their imaging system. However, it is not an easy task for the radiologic technologists to measure MTF accurately due to lack of their engineering and mathematical backgrounds. The objective of this study is to develop and provide for radiologic technologists a medical system imaging evaluation tool, so that they can measure and quantify system performance easily.

Factors Influencing Efficient Agrobacterium-mediated Transformation of Panicum spp. (Agrobacterium법에 의한 Panicum속 식물들의 효과적인 형질전환에 영향을 미치는 요인)

  • Seo, Mi-Suk;Takahara, Manabu;Takamizo, Tadashi
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.1
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    • pp.1-8
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    • 2011
  • Molecular techniques such as genetic transformation are powerful tools that can be used for the genetic modification of warm-season grasses. The P. meyerianum with high regeneration ability was used for establishing an Agrobacterium-mediated transformation system. We investigated various factors affecting Agrobacterium infection by examining GUS gene expression of pCAMBIA1304 vector. Among various concentration of acetosyringone and betaine tested for inoculation and co-cultivation, 10 mg/L acetosyringone and 60 mg/L betaine resulted in the highest transformation frequency in terms of GUS expression. The calli of 4 species of Panicum spp. with excellent tissue culture response were inoculated with Agrobacterium under the optimal infection conditions. The high activity of GUS gene was observed in all species and hygromycin-resistant calli expressing GFP were obtained in P. meyerianum, P. longijubatum, P. stapfianum and guineagrass Noh-PL1. Co-cultivated calli were transferred onto the selection medium containing hygromycin, and the hygromycin resistant calli were selected after 3 months. Hygromycin-resistant plantlets were then successfully regenerated from the calli and grown in a greenhouse. We confirmed stable insertion of hpt gene among the hygromycin-resistant plantlets of P. meyerianum by PCR analysis.

Fluidelastic Instability Analysis of the U-Tube Bundle of a Recirculating Type Steam Generator (재순환식 증기발생기 U-튜브군에 대한 유체탄성 불안정 해석)

  • 조종철;이상균;김웅식;신원기;은영수
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.1
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    • pp.200-214
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    • 1993
  • This paper presents the results of fluidelastic instability analysis performed for the U-tube bundle of a Westinghouse model 51 steam generator, one of the recirculating types designed at an early stage, in which the principal region of external cross-flow is associated with the U-bend portion of tube. The prerequisites for this analysis are detailed informations of the secondary side flow conditions in the steam generator and the free vibration behaviours of the U-tubes. In this study, the three-dimensional two-phase flow field in the steam generator has been calculated employing the ATHOS3 steam generator two-phase flow code and the ANSYS engineering analysis code has been used to calculate the free vibration responses of specific U tubes under consideration. The assessment of the potential instability for the suspect U-tubes, which is the final analysis process of the present work, has been accomplished by combining the secondary side velocity and density distributions obtained from the ATHOS3 prediction with the relative modal displacement and natural frequency data calculated using the ANSYS code. The damping of tubes in two-phase flow has been deduced from the existing experimental data by taking into account the secondary side void fraction effect. In operation of the steam generator, the tube support conditions at the tube-to-tube support plate intersections due to either tube denting degradation or deposition of tube support plate corrosion products or ingression of dregs. Thus, various hypothetical cases regarding the tube support conditions at the tube-to-tube support plate intersections have been considered to investigate the clamped support effects on the forced vibration response of the tube. Also, the effect of anti-vibration bars support in the curved portion of tube has been examined.

Wide-area Surveillance Applicable Core Techniques on Ship Detection and Tracking Based on HF Radar Platform (광역감시망 적용을 위한 HF 레이더 기반 선박 검출 및 추적 요소 기술)

  • Cho, Chul Jin;Park, Sangwook;Lee, Younglo;Lee, Sangho;Ko, Hanseok
    • Korean Journal of Remote Sensing
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    • v.34 no.2_2
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    • pp.313-326
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    • 2018
  • This paper introduces core techniques on ship detection and tracking based on a compact HF radar platform which is necessary to establish a wide-area surveillance network. Currently, most HF radar sites are primarily optimized for observing sea surface radial velocities and bearings. Therefore, many ship detection systems are vulnerable to error sources such as environmental noise and clutter when they are applied to these practical surface current observation purpose systems. In addition, due to Korea's geographical features, only compact HF radars which generates non-uniform antenna response and has no information on target information are applicable. The ship detection and tracking techniques discussed in this paper considers these practical conditions and were evaluated by real data collected from the Yellow Sea, Korea. The proposed method is composed of two parts. In the first part, ship detection, a constant false alarm rate based detector was applied and was enhanced by a PCA subspace decomposition method which reduces noise. To merge multiple detections originated from a single target due to the Doppler effect during long CPIs, a clustering method was applied. Finally, data association framework eliminates false detections by considering ship maneuvering over time. According to evaluation results, it is claimed that the proposed method produces satisfactory results within certain ranges.

Development of Image-map Generation and Visualization System Based on UAV for Real-time Disaster Monitoring (실시간 재난 모니터링을 위한 무인항공기 기반 지도생성 및 가시화 시스템 구축)

  • Cheon, Jangwoo;Choi, Kyoungah;Lee, Impyeong
    • Korean Journal of Remote Sensing
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    • v.34 no.2_2
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    • pp.407-418
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    • 2018
  • The frequency and risk of disasters are increasing due to environmental and social factors. In order to respond effectively to disasters that occur unexpectedly, it is very important to quickly obtain up-to-date information about target area. It is possible to intuitively judge the situation about the area through the image-map generated at high speed, so that it can cope with disaster quickly and effectively. In this study, we propose an image-map generation and visualization system from UAV images for real-time disaster monitoring. The proposed system consists of aerial segment and ground segment. In the aerial segment, the UAV system acquires the sensory data from digital camera and GPS/IMU sensor. Communication module transmits it to the ground server in real time. In the ground segment, the transmitted sensor data are processed to generate image-maps and the image-maps are visualized on the geo-portal. We conducted experiment to check the accuracy of the image-map using the system. Check points were obtained through ground survey in the data acquisition area. When calculating the difference between adjacent image maps, the relative accuracy was 1.58 m. We confirmed the absolute accuracy of the image map for the position measured from the individual image map. It is confirmed that the map is matched to the existing map with an absolute accuracy of 0.75 m. We confirmed the processing time of each step until the visualization of the image-map. When the image-map was generated with GSD 10 cm, it took 1.67 seconds to visualize. It is expected that the proposed system can be applied to real - time monitoring for disaster response.

Effect of cultivar and ascorbic acid on in vitro shoot regeneration and development of bombardment-mediated plastid transformation of tomato (Lycopersicon esculentum) (토마토 재분화 효율 향상 및 엽록체 형질전환 조건)

  • Roh, Kyung-Hee;Lee, Ki-Jong;Park, Jong-Sug;Kim, Jong-Bum;Lee, Seung-Bum;Suh, Seok-Cheol
    • Journal of Plant Biotechnology
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    • v.37 no.1
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    • pp.77-83
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    • 2010
  • Eighteen cultivars of tomato were tested for their regeneration response. Lycopersicon esculentum cv. 2001-58 showed a very high frequency of regeneration (93%). We evaluated the effect of two compounds with known antioxidant activity (ascorbic acid and cystein). The use of ascorbic acid ($200\;-\;300\;{\mu}M/L$) has a positive effect on shoot regeneration. To develope a system for plastid transformation in tomato via homologous recombination, we constructed the tomato plastid expression vector (pKRT22-AG) harboring 2.2 kb flanking sequences cloned from intact plastid genome and gfp gene. To investigate the factors affecting the delivery system of the pKRT22-AG into chloroplast using bombardment, We assessed the optimal DNA concentration, gold particle volume and target distance. Expression of the GFP protein was observed within chloroplast on protoplast of cotyledon explant by confocal laser scanning microscopy, which indicates that the protocol developed in this study be useful for the production of plastid transgenic plants in tomato.

Relationship between oral-related knowledge and OHIP (Oral Health Impact Profile) in some high school students (일부 고등학생들의 구강관련지식과 구강건강영향지수와의 관계)

  • Lee, Sun-Mi;Kim, Eun-Ju;Lee, Duck-Hye
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.5
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    • pp.877-885
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    • 2010
  • Objectives : This study was carried out with the aim of utilizing it as basic data in a plan for oral health promotion by analyzing oral-health awareness in high school students of some districts in our country, and by analyzing physical, mental and social influential factors in oral health, through using OHIP(Oral Health Impact Profile). Methods : It surveyed by carrying out self-administered questionnaire research targeting 536 boy & girl high school students in the 1st and the 2nd grade at 3 high schools in some districts of Gyeonggi Province. Results : 1. As for experience of having not visited dental clinic, a case of having not visited accounted for 32.5%. On the other hand, a case of having visited accounted for 67.5%. As for the appearance of oral health education, only 2.8% responded as saying of having experience. 97.2% responded as saying of having not taken oral health education. 2. As for oral health state perceived by oneself, the response as saying of 'thinking it to be healthy' and that 'there is something wrong' showed the distribution of 34.1% that is the same ratio. As for oral health interest, a case of having a little interest(58.4%) or of being so much interested(12.5%) showed 70.9%. A case of having no special interest(24.8%) or of having no interest at all(4.3%) showed the level of 29.1%.3. As for oral health knowledge, the toothbrushing knowledge was the highest with 4.54 marks out of 6-point perfection. The toothbrush knowledge(4-point perfection) showed low point with 2.05 marks. 4. By gender, a case of men was high in OHIP(Oral Health Impact Profile) for the functional restriction and physical pain. On the other hand, in the remaining sphere, women were indicated to be high in OHIP. The statistically significant difference was indicated in the spheres such as physical pain, psychological discomfort, a drop in psychological ability, a drop in social ability, and social separation. 5. According to oral health state perceived by oneself, a case of thinking it to be healthy was indicated to be high in OHIP for every sphere. A case of thinking it to have gum disease was indicated to be low in OHIP for every sphere. The statistically significant difference was indicated in every sphere except the sphere of functional restriction. 6. As for a factor of having influence upon OHIP according to oral health knowledge, it was indicated that the higher toothbrush knowledge leads to having more influence upon OHIP. Conclusions : It could be known that the oral health knowledge and OHIP are varied as well according to the oral health interest level. Also, the oral health education proper for subjects is not being performed. Even as for frequency of visiting the dentist, a regular visit is failing to be made. In consideration of these points, the diversified and effective educational program is likely considered to be necessarily developed and improved that subjects can have more interest in oral health.

A Study on the Actual Utilization Korean Traditional Remedies -About foods used on geriatric disease- (한국(韓國)의 전통적(傳統的) 민간요법(民間療法)의 이용실태(利用實態) 조사연구(調査硏究) -성인병(成人病)에 이용(利用)되는 식품(食品)을 중심(中心)으로-)

  • Lee, Keum-Sook;Hwang, Choon-Sun
    • Journal of the Korean Society of Food Culture
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    • v.5 no.3
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    • pp.331-347
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    • 1990
  • This study was designed under the purpose to analyze the Korean Traditional Folk Remedies on food, to submit the basic statistical data, and to utilize them by examining how much they know about the Korean Traditional Folk Remedies and also by examining how frequently they used them. The sample was consisted of 312 housewives living in Daegu, Kyungsan city and Kyungsan-eup, the survey was made by use of questionaires from July 15 to August 1 1989. The results are as follows 1. Analysis of Folk Remedical Contents 1) The method of the Folk Remedies used in this area was mainly food, which can be easily found around their house and easy to use, it was possible to apply scientific principles in some cases. 2) The major popular method was shown to feed boiled barley or brown rice which are known as the Folk Remedy for Diabetes. 3) The ANOVA of variable shows the significant influence on each object which age, religion, the level of education, job, monthly income, and the area except family formation. 2. The Frequency of Folk Remedies and additional analysis 1) The most frequently used Folk Remedy was Arterio-sclerosis(1.44), which is followed by the loss of Eyesight(1.40), Hang over(1.28), Couth(1.27), Cold(1.26) etc. 2) In the analysis of Pearson Correlation between frequencies of Folk Remedies used, and demographic variables such as age(p<.05), the monthly income(p<.01), in that area, total number of response items showed a positive correlation. 3. The source to learn about Folk Remedy. 1) It is acknoledged that they are mostly instructed by their forefathers, friends, neighbors, professional textbooks, mass communications, herb doctors, other medical sources or education at school etc. 2) The ANOVA of Variables shows the big differences between each group by age. Based on the above findings, the following suggestions are made ; Most of Korean Traditional Folk Remedies are recognized scientific and reasonable which are based on the scientific research and herb medicine therefore it should be made good use of for our life in good health additionally. I hereby insist that the importance of our Folk Remedies should be reviewed and focused for maintenance our health.

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Clinical Features, Response to Treatment, Prognosis, and Molecular Characterization in Korean Patients with Inherited Urea Cycle Defects

  • Yoo, Han-Wook;Kim, Gu-Hwan;Seo, Eul-Ju
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.2 no.1
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    • pp.77-79
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    • 2002
  • The urea cycle, consisting of a series of six enzymatic reactions, plays key roles to prevent the accumulation of toxic nitrogenous compound and synthesize arginine de novo. Five well characterized diseases have been described, resulting from an enzymatic defect in the biosynthesis of one of the normally expressed enzyme. This presentation will focus on two representative diseases; ornithine transcarbamylase(OTC) deficiency and citrullinemia(argininosuccinate synthetase deficiency). OTC deficiency is one of the most common inborn error of urea cycle, which is inherited in X-linked manner. We identified 17 different mutations in 20 unrelated Korean patients with OTC deficiency; L9X, R26P, R26X, T44I, R92X, G100R, R141Q, G195R, M205T, H214Y, D249G, R277W, F281S, 853 del C, R320X, V323M and 10 bp del at nt. 796-805. These mutations occur at well conserved nucleotide sequences across species or CpG hot spot. The L9X and R26X lead to the disruption of leader sequences, required for directing mitochondrial localization of the OTC precursor. Their phenotypes are severe, and neonatal onset. The G100R, R277W and V323M mutations were uniquely identified in patients with late onset OTC deficiency. The other genotypes are associated with neonatal onset. Out of 20 patients with OTC deficiency, only 6 patients are alive; two were liver transplanted, and normal in growth and development at 2, 4 years after transplantation respectively. Citrullinemia is an autosomal recessive disease, caused by the mutations in the argininosuccinate synthetase(ASS) gene. We identified in 3 major mutations in 11 unrelated Korean patients with citrullinemia; G324S, $IVS6^{-2}$ A to G, and 67 bp ins at nt 1125-1126. Among these, the 67 base pair insertion mutation is novel. The allele frequency of each mutation is; G324S(45%), IVS6-2 A to G(32%), and 67 base pair insertion(14%). All patients are diagnosed at neonatal or infantile age. Interestingly, two patients presented with stroke like episode. Out of 11 patients, 5 patients died. Among 6 patients alive, one patient was successfully liver transplanted.

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