• Journal of Yeungnam Medical Science
• /
• v.15 no.1
• /
• pp.55-66
• /
• 1998

Pathophysiological mechanism of hemorrhagic fever with renal syndrome (HFRS) is not fully understood. Major clinical findings of HFRS patients are widespread hemorrhage, acute renal failure and shock. Basic lesion is vascular injury with microvascular hemorrhage and relatively little inflammation. According to autopsy findings, renal medulla shows focal hemorrhage, tubular necrosis and interstitial mononuclear infiltrates. The predominant cell type in the renal and pulmonary interstitium is a fibroblast and it participates in the healing process at the injury site by secreting a large amount of extracellular matrix proteins. Cultured human lung fibroblasts and Mongolian gerbil fibroblasts were known to be good host cells for the hantaan virus. It is possible that not only the endothelial cell but also the fibroblast is a target of Hantaan virus and the fibroblast might be involved in the pathogenesis and the healing process in HFRS. Integrins are adhesion molecules, and act as receptors for many extracellular matrix proteins. Recently, there are many reports that cell surface integrins influence on some viral infections or reversely viruses influence on the expression of integrins. The ${\alpha}_5{\beta}_1$ integrin is a major receptor for the fibronectin which is an important extracellular matrix protein secreted by fibroblasts. In this study, the role of ${\alpha}_5{\beta}_1$ integrin in the infection of Hantaan virus was examined by using anti-${\alpha}_5{\beta}_1$, integrin, anti-${\alpha}_5$ integrin and anti-${\beta}_1$, integrin antibodies in chicken embryo fibroblasts (CEF) and Mongolian gerbil fibroblasts(MGF). The treatment of anti-${\alpha}_5{\beta}_1$, integrin antibody in CEF reduced the virion titers 26.8% and the amount of nucleocapsid N protein 32.6% when compared with control CEF. When MGF were treated with anti-${\alpha}_5$, anti-${\beta}_1$ and anti-${\alpha}_5{\beta}_1$ integrin antibodies, virion titers were reduced by 26.5%, 29.4% and 28.7% and the amount of nucleocapsid N protein were reduced by 65.2%, 59.7% and 72.6%. These results suggested that ${\alpha}_5{\beta}_1$ integrin might act as a receptor for the Hantaan virus or blocking of ${\alpha}_5{\beta}_1$ integrin influences on the viral replication in CEF and MGF. It is also possible that the blocking of only one subunit of integrin represents similar results in that of whole molecule.

• Journal of Korea Foundry Society
• /
• v.38 no.5
• /
• pp.103-110
• /
• 2018

The effects of a heat treatment on the carbide formation behavior and mechanical properties of the cobalt-based superalloy X-45 were investigated here. Coarse primary carbides formed in the interdendritic region in the as-cast specimen, along with the precipitation of fine secondary carbides in the vicinity of the primary carbides. Most of the carbides formed in the interdendritic region were dissolved into the matrix by a solution treatment at $1274^{\circ}C$. Solutionizing at $1150^{\circ}C$ led to the dissolution of some carbides at the grain boundaries, though this also caused the precipitation of fine carbides in the vicinity of coarse primary carbides. A solution treatment followed by an aging treatment at $927^{\circ}C$ led to the precipitation of fine secondary carbides in the interdendritic region. Very fine carbides were precipitated in the dendritic region by an aging heat treatment at $927^{\circ}C$ and $982^{\circ}C$ without a solution treatment. The hardness value of the alloy solutionized at $1150^{\circ}C$ was somewhat higher than that in the as-cast condition; however, various aging treatments did not strongly influence the hardness value. The specimens as-cast and aged at $927^{\circ}C$ showed the highest hardness values, though they were not significantly affected by the aging time. The specimens aged only at $982^{\circ}C$ showed outstanding tensile and creep properties. Thermal exposure at high temperatures for 8000 hours led to the precipitation of carbide at the center of the dendrite region and an improvement of the creep rupture lifetimes.

• Journal of the Korean Applied Science and Technology
• /
• v.32 no.4
• /
• pp.702-711
• /
• 2015

This study was conducted to determine the feasibility of using Gastrodia elata Blume as a cosmetic raw material by investigating the physiological activities of its extracts, varying the concentration, solvent, and fermentation method (non-fermentation and fermentation using lactic acid bacteria and effective microorganisms). Of the extracts in three different solvents-water, EtOH, and 70% EtOH-at four different concentrations (0.725, 1.25, 2.5, and 5 mg/mL), the EtOH extracts demonstrated the highest contents of antioxidants (flavonoids, polyphenols, and DPPH free radical scavengers). The DPPH free radical scavenging activity in the EtOH extracts of EM-fermented Gastrodia elata Blume increased from $27.08{\pm}0.5%$ at 1.25 mg/mL to $35.89{\pm}0.8%$ at 2.5 mg/mL. The tyrosinase inhibitory activity test was performed to measure skin-whitening capacity and revealed the LB-fermented EtOH extracts to be the most efficacious ($39.1{\pm}0.4%$ at 0.725 mg/mL, $62.8{\pm}1.5%$ at 2.5 mg/mL). Viability was found to exceed 85% in RAW 264.7 cells treated with all extracts (water, EtOH, 70% EtOH at 10, 25, $50{\mu}L$, fermented and non-fermented), thus proving that Gastrodia elata Blume extracts do not cause inflammation. When RAW 264.7 cells were stimulated with lipopolysaccharide as positive controls under the same conditions to determine the antioxidant activity in the presence of reactive oxygen species (ROS), EM-fermentation was found to impart excellent antioxidant capacity. This study verified the physiological activities of fermented Gastrodia elata Blume extracts that are best suited for cosmetic ingredients, such as antioxidants, tyrosinase inhibitors and anti-inflammatory agents.

• Korean Journal of Cognitive Science
• /
• v.19 no.4
• /
• pp.331-367
• /
• 2008

This study aims to validate a web-based neuropsychological testing tool developed by Kwak(2007) and to suggest solutions to potential problems that can deteriorate its validity. When it targets a wider range of subjects, a web-based neuropsychological testing tool is challenged by high drop-out rates, lack of motivation, lack of interactivity with the experimenter, fear of computer, etc. As a possible solution to these threats, this study aims to redesign the user interface of a web-based attention testing tool through three phases of study. In Study 1, an extensive analysis of Kwak's(2007) attention testing tool was conducted to identify potential usability problems. The Heuristic Walkthrough(HW) method was used by three usability experts to review various design features. As a result, many problems were found throughout the tool. The findings concluded that the design of instructions, user information survey forms, task screen, results screen, etc. did not conform to the needs of users and their tasks. In Study 2, 11 guidelines for the design of web-based attention testing tools were established based on the findings from Study 1. The guidelines were used to optimize the design and organization of the tool so that it fits to the user and task needs. The resulting new design alternative was then implemented as a working prototype using the JAVA programming language. In Study 3, a comparative study was conducted to demonstrate the excellence of the new design of attention testing tool(named graphic style tool) over the existing design(named text style tool). A total of 60 subjects participated in user testing sessions where their error frequency, error patterns, and subjective satisfaction were measured through performance observation and questionnaires. Through the task performance measurement, a number of user errors in various types were observed in the existing text style tool. The questionnaire results were also in support of the new graphic style tool, users rated the new graphic style tool higher than the existing text style tool in terms of overall satisfaction, screen design, terms and system information, ease of learning, and system performance.

• Journal of Korean Society of Forest Science
• /
• v.84 no.1
• /
• pp.103-113
• /
• 1995

To estimate buffer capacity and sensitivity of forest ecosystem to acid rain in Taejon, ionic components of throughfall, stemflow, soil leachate, and open rain in Pinus rigida and Quercus variabilis forest were analysed. The spatial sensitivity based on parent rock and forest type was given by IDRISI of GIS which created imagery conversion from soil and vegetation map. Parent rocks and soils were classified into acidic, sedimentary, metamorphic rock and then subdivided based on $SiO_2$ content. Average pH of vegetation leachate was higher in throughfall but lower in stemflow than open rain and higher in Quercus variabilis forest than in Pinus rigida forest. The flow of $SO{_4}^{2-}$, $NO_3{^-}$ and $Cl^-$ through vegetation leaching(throughfall plus stemflow) into soil were 7.2, 4.3, and 2.5 times, respectively, higher in Pinus rigida forest and 4.4, 2, and 2.5 times, respectively, higher in Quercus variabilis forest than in open field. But the concentration of exchangeable cations was 4.1 times higher in Pinus rigida forest and 4.6 times higher in Quercus variabilis forest than in open field. Average pH of soil leachate was lower than that of throughfall, but higher than that of stemflow. The concentration of exchangeable canons and $Al^{3+}$ in soil leachate were more in Pinus rigida forest than in Quercus variabilis forest and increase signficantly with the increase of acidic deposits. Pinus forest had more deposition and canopy interception of acidic pollutants and more nutrient loss than Quercus forest, and Quercus forest had more cation exchange and proton consumption and than consequently had less nutrient loss and better buffer capacity than Pinus forest. The 69% of forest soils was distributed on acidic rock, 25% of it on metamorphic rock, and 6% of it on intermediate and basic rock. Acidic rock residuals which had low very canon exchange capacity and high sensitivity to acid rain occupied a half of total forest land in Taejon area. Therefore forests in Taejon showed high vulnerability to acid rain and will receive much more stress with the increase of acid rain precursors.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.44 no.5
• /
• pp.59-67
• /
• 2016

In landscape design by public institutions, although the costs and species of landscape trees stipulated by the Korean Public Procurement Service(PPS) are generally adhered to, the PPS regulations about planting trees with well-developed rootlets are almost entirely neglected. This study aimed to evaluate the performance of buried container modules, which are a new technology and product in landscape production that is able to reduce the defect rate while complying with regulations. To this end, this study measured rootlet density, rootlet development length, rootlet survival rate on excavation, and impairments of tree growth for 3 months after root pruning, and compared these variables for the container modules with those for trees that underwent root pruning in bare ground, and those that were cultivated in a container above ground. The results were as follows: First, the rootlet density was 88% for the trees in container modules, which was very high. Trees that underwent standard root pruning in bare ground had a somewhat lower density of 64%. Meanwhile, the trees that were cultivated in pots above ground died, invalidating measurement. Second, in terms of rootlet development and rootlet survival rate, the trees in container modules showed a mean length of 10.4cm, and 100% survival rate, indicating that there was no rootlet damage caused by excavation. For the trees that only underwent root pruning in bare ground, the mean length was 25.6cm and the rootlet survival rate was only half that of the trees in container modules, at 56%, demonstrating considerable damage. Rootlet development did not occur at all in the trees grown in pots. Third, the trees in container modules and those that underwent root pruning in bare ground did not show any deaths during the root pruning process, or any impairments such as stunted leaf growth. Conversely, the trees grown in pots nearly all died, and severe impairments of tree growth were observed. As shown by the results above, when we evaluated the performance of buried container modules, they showed the most outstanding performance of the three models tested in this study. The container modules prevent defects by stimulating early rooting in environments that with poor conditions for growth, or in trees that are not suited to the summer environment Therefore, it is expected that they would be an optimal means by which to enable compliance with rules such as the regulation presented by the PPS.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.1
• /
• pp.123-136
• /
• 2004

In this paper, complexity and regularity of polynomial multiplication over $GF({2^n})$ are defined by using Hamming weight of rows and columns of the matrix ever GF(2) which represents polynomial multiplication. It is shown experimentally that in order to construct the block cipher robust against differential cryptanalysis, polynomial multiplication of substitution layer and the permutation layer should have high complexity and high regularity. With result of the experiment, a way of constituting S box and G function is suggested in the block cipher whose structure is similar to SEED, which is KOREA standard of 128-bit block cipher. S box can be formed with a nonlinear function and an affine transform. Nonlinear function must be strong with differential attack and linear attack, and it consists of an inverse number over $GF({2^8})$ which has neither a fixed pout, whose input and output are the same except 0 and 1, nor an opposite fixed number, whose output is one`s complement of the input. Affine transform can be constituted so that the input/output correlation can be the lowest and there can be no fixed point or opposite fixed point. G function undergoes linear transform with 4 S-box outputs using the matrix of 4${\times}$4 over $GF({2^8})$. The components in the matrix of linear transformation have high complexity and high regularity. Furthermore, G function can be constituted so that MDS(Maximum Distance Separable) code can be formed, SAC(Strict Avalanche Criterion) can be met, and there can be no weak input where a fixed point an opposite fixed point, and output can be two`s complement of input. The primitive polynomials of nonlinear function affine transform and linear transformation are different each other. The S box and G function suggested in this paper can be used as a constituent of the block cipher with high security, in that they are strong with differential attack and linear attack with no weak input and they are excellent at diffusion.

• Investigative Magnetic Resonance Imaging
• /
• v.6 no.2
• /
• pp.152-157
• /
• 2002

Purpose : The differential diagnosis between Modic type I degenerative spine and infectious spondylitis sometimes is difficult, because the affected bone marrows in both disease show similar signal intensity on conventional MR imaging. We evaluate the usefulness of diffusion-wighted MR imaging for differential diagnosis between Modic type I degenerative spine and infectious spondylitis. Materials and methods : The spin-echo and diffusion-weighted MR images of eight patients with Modic type I degenerative spines and 14 patients with infectious spondylitis diagnosed by clinical findings or CT-guided biopsies we re analyzed. The diffusion-weighted imaging sequence was based on reversed fast imaging with steady-state precession (PSIF). Signal intensity changes of the vertebral bone marrow on conventional spin-echo and diffusion-weighted MR imaging were compared between degenerative spine and infectious spondylitis. Results : On T1-weighte d images, the affeted bone marrow in both disease showed hypointense signals. On T 2-weighted images, all of type I degenerative spine and 11 of infectious spondylitis showed hyperintensity, and three of infectious spondylitis showed heterogeneo us mixed signal intensity. On diffusion-weighted MR images, all of type I degenerative spine were hypointense with peripheral high signal intensity to normal vertebral body, but infectious spondylitis was hyperintense (n = 11) and hypointense (n=3). Conclusion : Diffusion-weighted MR imaging is useful to differentiate Modic type I degenerative spine from infectious spondylitis. On diffusion-weighted images, the high singal intensity of bone marrow suggests infectious spondylitis, whereas the low signal intensity of bone marrow with peripheral focal high signal intensity suggests type I degenerative spine.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.6
• /
• pp.785-793
• /
• 2007

This study was carried out to investigate the effects of red yeast rice addition on the physical characteristics of sourdough starters ($SD1{\sim}4$) and the quality characteristics of sourdough bread (CSB, $SDB1{\sim}3$). Moisture contents of red yeast rice, wheat flour, and rye flour were 6.15, 12.53, and 8.56%; ash contents were 0.15, 0.44, and 1.64%; protein contents were 7.30, 12.57, and 11.18%; crude lipid contents were 0.97, 1.16, and 2.49%, respectively. The pH decreased with increasing red yeast rice addition. Reducing sugar and total sugar increased with increasing red yeast rice addition. Lactic acid bacteria were not detected from 0 day for all samples and was maximum on the 2nd day. The yeast counts of SD1 were not detected from $0{\sim}4th$ day, but $SD2{\sim}4$ increased until the 3rd day. Peak time, peak value, and width of tail of CSB were higher than $SDB1{\sim}3$, and they increased with increasing red yeast rice contents of sourdough. The fermentation expansive power of $SDB1{\sim}3$ was higher than that of CSB. Baking loss and specific volume of SDB1 were higher than other samples and when baking loss of CSB and SDB1${\sim}$3 increased, the specific volume increased. L values decreased with increasing red yeast rice contents of sourdough bread whereas, a and b values increased. Springiness and brittleness of CSB and gumminess of SCB1 were lower than other samples. Springiness, brittleness, and gumminess increased with increasing red yeast rice content of sourdough bread. The sensory evaluation indicated that color, hardness, springiness, sweetness, and sourness increased with increasing red yeast rice content of sourdough bread. Aircell non-uniformity of SDB1 was lower than other samples, whereas off-flavor was higher than other samples.

• The KIPS Transactions:PartD
• /
• v.13D no.7 s.110
• /
• pp.985-996
• /
• 2006

As the internet technologies develop, the geographic information system environment is changing to the web-based service. Since geospatial information of the existing Web-GIS services were developed independently, there is no interoperability to support diverse map formats. In spite of the same geospatial information object it can be used for various proposes that is duplicated in GIS separately. It needs intelligent strategies for optimal replica selection, which is identification of replication geospatial information objects. And for management of replication objects, OMG, GLOBE and GRID computing suggested related frameworks. But these researches are not thorough going enough in case of geospatial information object. This paper presents a model of location service, which is supported for optimal selection among replication and management of replication objects. It is consist of tree main services. The first is binding service which can save names and properties of object defined by users according to service offers and enable clients to search them on the service of offers. The second is location service which can manage location information with contact records. And obtains performance information by the Load Sharing Facility on system independently with contact address. The third is intelligent selection service which can obtain basic/performance information from the binding service/location service and provide both faster access and better performance characteristics by rules as intelligent model based on rough sets. For the validity of location service model, this research presents the processes of location service execution with Graphic User Interface.