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This study was conducted on the field application for a method which is currently used. Although the method was performed with experimental knowledge, this study attempted to approach scientific ways through thirty sets of test-bed and... more
This study was conducted on the field application for a method which is currently used. Although the method was performed with experimental knowledge, this study attempted to approach scientific ways through thirty sets of test-bed and three times monitoring limited by control variations for three months. The factors on previous studies are slope location, slope degree, type (roadfill vs. roadcut), aspect, vegetation cover, species, thickness, vertical length, horizontal length, soil type, elevation, erosion, soil-moisture, soil-hardness, pH, and so on. However, the factors of a suitable and significant level are slope degree, type, aspect, thickness, soil-moisture, vertical length and horizontal length in slope revegetation. the results were as follows : As a result of survey on soil types based on the status before construction, the rate of vegetation cover with non-mesh construction in soil areas was better than the rate of vegetation cover with fiber meshes and wire meshes. The ...
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Abstract The effects of urban heat islands (UHIs) comprise one of the most challenging issues in mitigating excessive heat. Existing studies have reported cooling effects from small greenspaces (SGs) and building-shaded spaces (BSs).... more
Abstract The effects of urban heat islands (UHIs) comprise one of the most challenging issues in mitigating excessive heat. Existing studies have reported cooling effects from small greenspaces (SGs) and building-shaded spaces (BSs). However, more empirical studies are necessary to fully investigate the role of SGs in heat reduction as a cooling solution for urban microclimatic design and planning. In addition, only a few previous studies have used field studies to examine the cooling effects of SGs and compare them to those of BSs. The purpose of this study was to assess the cooling degrees of SGs and BSs and compare them at the urban block level. Six urban blocks located in Seoul, South Korea were selected as the study area. Based on block size, the selected urban blocks were divided into three pairs featuring different sizes of greenspace. Air temperature was measured via a transect survey on six clear, hot summer days. Datapoints were then classified into three landcover types: SGs, BSs, and paved spaces (PSs) exposed to solar radiation. To measure the cooling effects and compare the air temperatures of each cooling factor, a series of T-tests and ANOVA tests were conducted, after performing a spatial analysis of each block. The result show that the cooling effects of SGs surpassed those of BSs. The SGs’ cooling effects on blocks with larger greenspace were greater than those with small greenspace. In blocks with larger greenspace, SG’s cooling benefits outweighed those of BSs. It is also notable that block size was a decisive factor affecting the magnitude of cooling degrees; SG brought the greatest microclimatic benefits for the largest blocks. Our findings will contribute to optimal cooling designs using SGs and BSs by illustrating where SGs should be included to facilitate cost-effective cooling.
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Research Interests: Geography, Physical Geography, Spatial Analysis, Spatial Ecology, Environmental Monitoring, and 15 moreMedicine, Multidisciplinary, Spatial autocorrelation, Cities, Land Cover, Environmental public health, Land Use, Temperature, Land Surface Temperature, Texas, Landscape Pattern, Environment, Geographic Information Systems, Common Spatial Pattern, and Residence Characteristics
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Research Interests:
The purpose of this study was to determine the types and structures of small green spaces (SGs) that effectively reduce air temperature in urban blocks. Six highly developed blocks in Seoul, South Korea served as the research sites for... more
The purpose of this study was to determine the types and structures of small green spaces (SGs) that effectively reduce air temperature in urban blocks. Six highly developed blocks in Seoul, South Korea served as the research sites for this study. Air temperature was measured at the street level with mobile loggers on clear summer days from August to September in 2012. The measurements were repeated three times a day for three days. By analyzing the spatial characteristics, SGs within the six blocks were categorized into the four major types: polygonal, linear, single, and mixed. The result revealed that the polygonal and mixed types of SGs showed simple linear regression at a significant level (p < 0.01). It indicated that the blocks' urban heat island (UHI) mitigation (T Rmn) increased in a linear fashion when the area and volume of these two types of green spaces increased. The area and volume of a polygonal SG with mixed vegetation, over 300 m 2 and 2300 m 3 , respectively, lowered the T Rmn by 1 • C; SG with an area and volume of larger than 650 m 2 and 5000 m 3 , respectively, lowered the T Rmn by 2 • C. The results of this study will be useful to urban planners and designers for determine the types and structures of urban green spaces to optimize the cooling effect, as well as how such green spaces should be designed and distributed.
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Molecular imaging is a novel technology to visualize biological processes at the cellular and molecular levels, which is reshaping both biomedical research and clinical practice. By providing molecular information to supplement and... more
Molecular imaging is a novel technology to visualize biological processes at the cellular and molecular levels, which is reshaping both biomedical research and clinical practice. By providing molecular information to supplement and augment conventional anatomy-based imaging, molecular imaging is expected to allow 1) the earlier detection of diseases, 2) precise evaluation of disease stages, and 3) both diagnostic and therapeutic monitoring of disease progression in a quantitative manner. In this brief review, we present our view on the prospects of molecular optical imaging in the field of stroke practice, focusing on the imaging vulnerability of atherosclerotic plaques, thrombolytic resistance, real-time cerebral perfusion, and penumbra.
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Monocyte adhesion to vascular endothelium has been reported to be one of the early processes in the development of atherosclerosis. In an attempt to develop strategies to prevent or delay atherosclerosis progression, we analyzed effects... more
Monocyte adhesion to vascular endothelium has been reported to be one of the early processes in the development of atherosclerosis. In an attempt to develop strategies to prevent or delay atherosclerosis progression, we analyzed effects of the Wnt/beta-catenin signaling pathway on monocyte adhesion to various human endothelial cells. Adhesion of fluorescein-labeled monocytes to various human endothelial cells was analyzed under a fluorescent microscope. Unlike sodium chloride, lithium chloride enhanced monocyte adhesion to endothelial cells in a dose-dependent manner. We further demonstrated that inhibitors for glycogen synthase kinase (GSK)-3beta or proteosome enhanced monocyte-endothelial cell adhesion. Results of semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) indicated that activation of Wnt/beta-catenin pathway did not change expression levels of mRNA for adhesion molecules. In conclusion, the canonical Wnt/beta-catenin pathway enhanced monocyte-endot...
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ABSTRACT Angiofibromas arise from soft tissue, but occur rarely in the nasal cavity. Of these, only six cases have risen from inferior turbinate. Six such cases have been reported previously in English literature and only 1 case in Korea.... more
ABSTRACT Angiofibromas arise from soft tissue, but occur rarely in the nasal cavity. Of these, only six cases have risen from inferior turbinate. Six such cases have been reported previously in English literature and only 1 case in Korea. We present an atypical case of an angiofibroma arising from the inferior turbinate in a 57-year-old woman. The mass was removed with endoscopic approach without massive bleeding.
Repeated injections of cocaine alter extracellular nitric oxide (NO) efflux via interactions between dopamine and glutamate receptor-coupled signaling cascades. Putative cellular mechanisms underlying changes in NO efflux following... more
Repeated injections of cocaine alter extracellular nitric oxide (NO) efflux via interactions between dopamine and glutamate receptor-coupled signaling cascades. Putative cellular mechanisms underlying changes in NO efflux following repeated cocaine administration were investigated. Real-time detection of NO efflux using a NO biosensor was mainly performed in the rat dorsal striatum in vivo. Repeated exposure to cocaine (20 mg/kg), once a day for seven consecutive days, increased NO levels. Repeated injections of cocaine also increased the phosphorylation of neuronal nitric oxide synthase (nNOS), and inhibition of nNOS decreased the repeated cocaine-evoked increases in NO levels. Inhibition of protein kinase A, but not protein phosphatases, synergistically increased NO levels elevated by repeated cocaine injections. Blockade of dopamine D1 (D1) receptors or stimulation of dopamine D2 (D2) receptors decreased the repeated cocaine-evoked increases in NO levels. Similarly, blockade of N-methyl-D: -aspartate (NMDA) receptors and group I metabotropic glutamate receptors (mGluRs) or stimulation of group III mGluRs also decreased the repeated cocaine-evoked increases in NO levels. Stimulation of D1 receptors or group I mGluRs following repeated cocaine administration upregulates NO efflux via an NMDA receptor-evoked Ca2+ influx, while stimulation of D2 receptors or group III mGluRs downregulates NO efflux. Dephosphorylation of phosphorylated nNOS by protein phosphatases is necessary for upregulating NO efflux in the dorsal striatum after repeated cocaine administration.
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Rehabilitation after a stroke is very important because it has beneficial effects on brain function, including the promotion of plasticity. However, an optimal time window for rehabilitation interventions after hemorrhagic stroke has not... more
Rehabilitation after a stroke is very important because it has beneficial effects on brain function, including the promotion of plasticity. However, an optimal time window for rehabilitation interventions after hemorrhagic stroke has not been clearly defined. The aim of this study was to determine whether early exercise training initiated 24h after an intracerebral hemorrhage (ICH) might enhance neurologic recovery more than exercise initiated 1 week after ICH without hematoma expansion and edema volume increase. We subjected adult male Sprague-Dawley rats to experimental ICH by the intrastriatal administration of bacterial collagenase. The rats were randomly divided into the following 2 groups: early training group (treadmill exercise started 24h post-ICH; n=18) and late training group (treadmill exercise started 1-week post-ICH; n=18). Two weeks after surgery we performed neurologic tests (rota-rod, modified limb-placing, and adhesive-dot removal tests), and measured hematoma volumes and brain water content. In the late training group, compared with the pre-ICH performance on the rota-rod test (98.3+/-69.4s), the animals had significantly worse performance after the post-ICH rehabilitation (40.5+/-52.6s; p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.01, paired t-test). In the early training group however, the motor performance after the post-ICH rehabilitation (56.4+/-73.5s) was not significantly different from the baseline pre-ICH performance (79.8+/-33.9s; p=0.24). There were no significant differences between the two groups with respect to the other neurologic tests. Early exercise did not increase hematoma size or brain water content. Early treadmill training could be performed safely, and enhanced motor recovery in a rat model of ICH. Further studies are required to translate the results into clinical significance.
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The radial distribution of the delta [Oi] for the heavily doped silicon wafers was investigated using X-ray diffraction technique. In order to obtain the correlation between delta [Oi] and X-ray intensity ratio for the lightly doped... more
The radial distribution of the delta [Oi] for the heavily doped silicon wafers was investigated using X-ray diffraction technique. In order to obtain the correlation between delta [Oi] and X-ray intensity ratio for the lightly doped wafers with different initial [Oi] concentrations, the oxygen concentration using FTIR and X-ray intensity were measured before and after two-step annealing. The relation between delta [Oi] and X-ray intensity ratio showed that it was close to the parabolic correlation rather than the linear correlation. The deviation of this measurement was about ±0.4ppma. This correlation equation could be applied to the heavily doped wafers. It is shown that the radial distribution of the delta [Oi] is not uniform in the radial direction but has the symmetric relation at the wafer center. The bulk micro defect (BMD) density using etching method was measured to confirm these results.
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Research Interests: Prostate Cancer, Enzyme Inhibitors, Biological Chemistry, Transcription Factors, Biological Sciences, and 14 moreCell line, Humans, Mutation, Male, Kinase inhibitor, Plasmids, Transcription Factor, CHEMICAL SCIENCES, Cell nucleus, Androgen Receptor, Transfection, Protein Binding, Prostate Specific Antigen, and Ligands
Research Interests: Analytical Chemistry, Biomedical Engineering, Electrochemistry, Nanotechnology, Cyclic Voltammetry, and 18 moreElectron Transfer, Conducting Polymer, Nitric oxide, Calibration, Animals, Male, Cytochrome C, Rat Brain, Microelectrodes, Electron Transport, Hydrogen Peroxide, Rats, Sensitivity and Specificity, High Sensitivity, Brain Chemistry, Modified Electrode, Oxidation-Reduction, and Biosensing Techniques
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Monocyte adhesion to vascular endothelium has been reported to be one of the early processes in the development of atherosclerosis. In an attempt to develop strategies to prevent or delay atherosclerosis progression, we analyzed effects... more
Monocyte adhesion to vascular endothelium has been reported to be one of the early processes in the development of atherosclerosis. In an attempt to develop strategies to prevent or delay atherosclerosis progression, we analyzed effects of the Wnt/beta-catenin signaling pathway on monocyte adhesion to various human endothelial cells. Adhesion of fluorescein-labeled monocytes to various human endothelial cells was analyzed under a fluorescent microscope. Unlike sodium chloride, lithium chloride enhanced monocyte adhesion to endothelial cells in a dose-dependent manner. We further demonstrated that inhibitors for glycogen synthase kinase (GSK)-3beta or proteosome enhanced monocyte-endothelial cell adhesion. Results of semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) indicated that activation of Wnt/beta-catenin pathway did not change expression levels of mRNA for adhesion molecules. In conclusion, the canonical Wnt/beta-catenin pathway enhanced monocyte-endothelial cell adhesion without changing expression levels of adhesion molecules.
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Few studies have investigated if exercise by itself has anti-atherosclerotic effects, without combining interventions with a low-fat diet. We studied the effects of exercise as a stand-alone intervention on preexisting atheromata by... more
Few studies have investigated if exercise by itself has anti-atherosclerotic effects, without combining interventions with a low-fat diet. We studied the effects of exercise as a stand-alone intervention on preexisting atheromata by measuring not only plaque size but also the levels of plaque-destabilizing matrix-metalloproteinase (MMP) activity in vivo. We used near-infrared fluorescent (NIRF) molecular imaging with an MMP-2/9 activatable NIRF probe to visualize the inflammatory protease activity within preexisting atheromata of 17-week-old ApoE(-/-) mice on: (a) normal chow diet (NCD), (b) Western diet (WD), and (c) WD with treadmill exercise for 10 weeks. We also measured tissue levels of aortic lipid peroxidation (LPO) and plasma levels of glucose/lipid/cytokine profiles. Exercise did not attenuate growth of preexisting atheromatous plaques. However, exercise strongly decreased proteolytic activity in plaques for animals on WD, with levels decreasing almost to NCD levels. Exercise was associated with decreased aortic LPO levels and increased blood adiponectin/leptin levels; however, exercise did not affect WD-consumption/weight-gain or improve blood glucose/lipid profiles. Exercise training reduced aortic MMP activity in mice with preexisting atheromata, even though they remained on a high fat diet and plaque-growth was not attenuated.
Research Interests: Microscopy, Atherosclerosis, Cytokines, Immunohistochemistry, Exercise therapy, and 15 moreMolecular Imaging, Lipids, Blood Glucose, Mice, Animals, Leptin, Lipid peroxidation, Clinical Sciences, Adiponectin, Analysis of Variance, Body Weight, Aorta, Infrared Rays, Matrix Metalloproteinase, and Down-Regulation
The aim of this study was to identify the major variables identified as important for considering the stabilization of slope revegetation based on hydroseeding applications and evaluate weights of each variable using the analytic... more
The aim of this study was to identify the major variables identified as important for considering the stabilization of slope revegetation based on hydroseeding applications and evaluate weights of each variable using the analytic hierarchy process (AHP) with both environmental experts and civil engineers. Twenty-five variables were selected by the experts’ survey from a total of 65 from the existing literature, with each variable considered as an important factor for slope stabilization in South Korea. The final results from the AHP method showed that variables associated with the driving force of water resources showed higher values in all expert groups such as rain intensity, seepage water and drainage condition. Other important variables were related to plant growth such as vegetation community, vegetation coverage and quality of soil ameliorant produced in an artificial factory such as tensile strength, permeability coefficient, soil texture and organic matter. The five highest-ranked variables that satisfied both environmental experts and civil engineers were rain intensity, seepage water, slope angle, drainage condition and ground layer. The findings of this research could be helpful for developing a more accurate rating system to evaluate the stability of slope revegetation.