• 한국환경과학회지
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• 제5권3호
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• pp.285-295
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• 1996

In genneral, Businger expression is used for determining a turbulance diffusion coefficient. In this study, it is applied to the surface elements of cities such as Asphalt, Cround, Grass, Pond. We set up 5 m-height bar and measured the ary temperature and wet temperature at 도 height of 0.13, 0.27, 0.5, 1, 0, 3.0, 5.0m. In addition we measured the wind gradient and wind velocity at the height 3 m solar radiation continuously for 48 hours on the surface. Compared the measured data to Businger expression the result showed that Businger expression can be well applied to the complex surface of the city.

• The Korean Journal of Physiology and Pharmacology
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• 제26권3호
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• pp.175-182
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• 2022

Translocation of azurophil granules is pivotal for bactericidal activity of neutrophils, the first-line defense cells against pathogens. Previously, we reported that lysophosphatidylcholine (LPC), an endogenous lipid, enhances bactericidal activity of human neutrophils via increasing translocation of azurophil granules. However, the precise mechanism of LPC-induced azurophil granule translocation was not fully understood. Treatment of neutrophil with LPC significantly increased CD63 (an azurophil granule marker) surface expression. Interestingly, cytochalasin B, an inhibitor of action polymerization, blocked LPC-induced CD63 surface expression. LPC increased F-actin polymerization. LPC-induced CD63 surface expression was inhibited by both a Rho specific inhibitor, Tat-C3 exoenzyme, and a Rho kinase (ROCK) inhibitor, Y27632 which also inhibited LPC-induced F-actin polymerization. LPC induced Rho-GTP activation. NSC23766, a Rac inhibitor, however, did not affect LPC-induced CD63 surface expression. Theses results suggest a novel regulatory mechanism for azurophil granule translocation where LPC induces translocation of azurophil granules via Rho/ROCK/F-actin polymerization pathway.

• 한국생산제조학회지
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• 제26권3호
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• pp.328-336
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• 2017

The exit surface of a lens is designed using a three-dimensional free-form expression in order to easily modify a curved surface. This enables the design of numerical values and mathematical things using three-dimensional free-form expression, and enhances precision because it can be fine-tuned via numerical control. The standard of "Classification of Luminaire Light Distribution" for outdoor lighting fixtures by IESNA is adopted in order to examine the correlation between three-dimensional free-form surface expression and lighting performance. The variation of light distribution type and range is analyzed using the values of maximum light intensity and 50% light intensity. The actual tolerance occurs owing to parameters such as the thickness of the lens, the distance between LEDs, and the movement of the center of the incident surface; the effects of changes in these parameters on the performance are compared and analyzed.

• Korean Chemical Engineering Research
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• 제58권2호
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• pp.280-285
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• 2020

We have developed a constitutive display system of the Pseudomonas fluorescens SIK W1 TliA lipase on the cell surface of Escherichia coli using E. coli outer membrane protein C (OmpC) as an anchoring motif, which is an economical compared to induced system. For the constitutive expression of truncated OmpC-TliA fusion proteins, gntT104 promoter was employed. Cell growth was not affected by over expression of fusion protein during entire culture time, suggesting cell lysis was not a problem. The localization of truncated OmpC-TliA fusion protein on the cell surface was confirmed by immunofluorescence microscopy and measuring whole cell lipase activity. Constitutively displayed lipase was very stable, retaining activity enantioselectivity throughout the five repeated reactions. These results suggest that OmpC from E. coli be a useful anchoring motif for displaying enzymes on the cell surface without any inducers, and this stable surface display system can be employed for a broad range of biotechnological applications.

• Journal of Periodontal and Implant Science
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• 제42권3호
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• pp.95-104
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• 2012

Purpose: The purpose of this study was to determine whether increasing the Ti6Al4V surface oxide negative charge through heat ($600^{\circ}C$) or radiofrequency plasma glow discharge (RFGD) pretreatment, with or without a subsequent coating with fibronectin, stimulated osteoblast gene marker expression in the MC3T3 osteoprogenitor cell line. Methods: Quantitative real-time polymerase chain reaction was used to measure changes over time in the mRNA levels for osteoblast gene markers, including alkaline phosphatase, bone sialoprotein, collagen type I (${\alpha}1$), osteocalcin, osteopontin and parathyroid hormone-related peptide (PTH-rP), and the osteoblast precursor genes Runx2 and osterix. Results: Osteoprogenitors began to differentiate earlier on disks that were pretreated with heat or RFGD. The pretreatments increased gene marker expression in the absence of a fibronectin coating. However, pretreatments increased osteoblast gene expression for fibronectin-coated disks more than uncoated disks, suggesting a surface oxide-mediated specific enhancement of fibronectin's bioactivity. Heat pretreatment had greater effects on the mRNA expression of genes for PTH-rP, alkaline phosphatase and osteocalcin while RFGD pretreatment had greater effects on osteopontin and bone sialoprotein gene expression. Conclusions: The results suggest that heat and RFGD pretreatments of the Ti6Al4V surface oxide stimulated osteoblast differentiation through an enhancement of (a) coated fibronectin's bioactivity and (b) the bioactivities of other serum or matrix proteins. The quantitative differences in the effects of the two pretreatments on osteoblast gene marker expression may have arisen from the unique physico-chemical characteristics of each resultant oxide surface. Therefore, engineering the Ti6Al4V surface oxide to become more negatively charged can be used to accelerate osteoblast differentiation through fibronectin-dependent and independent mechanisms.

• 대한치과보철학회지
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• 제45권6호
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• pp.787-794
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• 2007

Statement of problem. Surface microgrooves on Ti substrata have been shown to alter the expression of genes responsible for various biological activities of cultured fibroblasts. However, their effect on enhancing cell proliferation is not yet clear. Purpose. The purpose of this study was to determine the dimension of surface microgrooves on Ti substrata that enhances proliferation and alters gene expression of cultured human gingival fibroblasts. Material and methods. Commercially pure Ti discs with surface microgrooves of monotonous $3.5{\mu}m$ in depth and respective 15 and $30{\mu}m$ in width were fabricated using photolithography and used as the culture substrata in the two experimental groups in this study (TiD15 and TiD30), whereas the smooth Ti was used as the control substrata (smooth Ti group). Human gingival fibroblasts were cultured on the three groups of titanium substrata and the proliferation, DNA synthesis, and gene expression of theses cells were analyzed and compared between all groups using XTT assay, BrdU assay, and reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. Results. From the XTT assay at 48 h incubation, the proliferation of human gingival fibroblasts in TiD30 was significantly enhanced compared to that in smooth Ti and TiD15. The results from the BrdU assay showed that, at 24 h incubation, the DNA synthesis was significantly enhanced in TiD30 compared to that in smooth Ti. In RT-PCR, increase in the expression of PCR transcripts of fibronectin, CDK6, $p21^{cip1}$ genes was noted at 48h incubation. Conclusion. Surface microgrooves $30{\mu}m$ in width and $3.5{\mu}m$ in depth on Ti substrata enhance proliferation and alter gene expression of cultured human gingival fibroblasts.

• IMMUNE NETWORK
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• 제1권1호
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• pp.14-25
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• 2001

Background: Bone marrow stromal cells (BMSCs) express many cell surface molecules, which regulate the proliferation and differentiation of immune cells within the bone marrow. Methods: To identify cell surface molecules, which can regulate cell proliferation through cell interaction, monoclonal antibodies (MoAbs) against BMSCs were produced. Among them, 1H8 MoAb, which recognized distinctly an 80 kDa protein, abolished myeloma cell proliferation that was induced by co-culturing with BMSCs. Results: IL-6 gene expression was increased when myeloma or stromal cells were treated with 1H8 MoAb. In addition, the expression of IL-6 receptor and CD40 was up-regulated by 1H8 treatment, suggesting that the molecule recognized by 1H8 MoAb is involved in cell proliferation by modulating the expression of cell growth-related genes. Myeloma cells contain high levels of reactive oxygen species (ROS), which are related to gene expression and tumorigenesis. Treatment with 1H8 decreased the intracellular ROS level and increased PAG antioxidant gene concomitantly. Finally, 1H8 induced the tyrosine phosphorylation of several proteins in U266. Conclusion: Taken together, 1H8 MoAb recognized the cell surface molecule and triggered the intracellular signals, which led to modulate gene expression and cell proliferation.

• Carbon letters
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• 제14권1호
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• pp.14-21
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• 2013

Physically and chemically activated carbons (ACs) exhibited high adsorption capacities for organic and inorganic pollutants compared with other adsorbents due to their expanded surface areas and wide pore volume distribution. In this work, seven steam-ACs with different burn-off have been prepared from cotton stalks. The textural properties of these sorbents were determined using nitrogen adsorption at $-196^{\circ}C$. The chemistry of the surface of the present sorbents was characterized by determining the surface functional C-O groups using Fourier transform infrared spectroscopy, surface pH, $pH_{pzc}$, and Boehm's acid-base neutralization method. The textural properties and the morphology of the sorbent surface depend on the percentage of burn-off. The surface acidity and surface basicity are related to the burn-off percentage. A theoretical model was developed to find a mathematical expression that relates the % burn-off to ash content, surface area, and mean pore radius. Also, the chemistry of the carbon surface is related to the % burn-off. A mathematical expression was proposed where % burn-off was taken as an independent factor and the other variable as a dependent factor. This expression allows the choice of the value of % burn-off with required steam-AC properties.

• 조형예술학연구
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• 제6권
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• pp.267-287
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• 2004

The study of a new expression within Korean ink painting that meets the demands of the times has continued, resulting in various expressions with acrylics, handycoat, objects and installations, crossing over from traditional Korean painting techniques. A 'margin' was both a very important space and esthetical matter that expresses 'Ki', 'Distance', and 'Omission' in traditional sense when addressing Korean ink painting Its expression methods and concepts, however, have changed today. A 'margin' through Montage technique can be a significant example in understanding the expression methods of today's Korean ink painting. This is because the margins in Montage make the meaning of the work various and flourished and deeply construct the surface with a double-layered structure, instead of using a single layer. These 'margins' created by Montage are spaces where different images conflict, divide and continue with each other and where a reconciliation between different spaces is accomplished. Furthermore, they establish more vitality and truthfulness to life through both the images conflict and reconciliation. After the adoption of Post-modernism Art in Korean ink painting, the characteristics of the 'margin' in Montage style by the division of surface are an 'acceptant's participatory imaginative space'; where viewers fill the margins with their imaginations ; an 'abandoned space' ; where unnecessary parts are deleted for more live surface ; and a 'strategic space', where the work enriches the structure and contents of surface by using margins strategically.

• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.157-164
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• 2014

PURPOSE. This study focused on in vitro cell differentiation and surface characteristics in a magnesium coated titanium surface implanted on using a plasma ion source. MATERIALS AND METHODS. 40 commercially made pure titanium discs were prepared to produce Ti oxide machined surface (M) and Mg-incorporated Ti oxide machined surface (MM). Surface properties were analyzed using a scanning electron microscopy (SEM). On each surface, alkaline phosphatase (ALP) activity, alizarin red S staining for mineralization of MC3T3-E1 cells, and quantitative analysis of osteoblastic gene expression, were evaluated. Actin ring formation assay and gene expression analysis of TRAP and GAPDH performing RT-PCR were performed to characterize osteoclast differentiation on mouse bone marrow-derived macrophages (BMMs). RESULTS. MM showed similar surface morphology and surface roughness with M, but was slightly smoother after ion implantation at the micron scale. M was more hydrophobic than MM. No significant difference between surfaces on ALP activity at 7 and 14 days were observed. Real-time PCR analyses showed similar levels of mRNA expression of the osteoblast phenotype genes; osteopontin (OPN), osteocalcin (OCN), bone sialoprotein (BSP), and collagen 1 (Col 1) in cell grown on MM at 7, 14 and 21 days. Alizarin red S staining at 21 days showed no significant difference. BMMs differentiation increased in M and MM. Actin ring formation assay and gene expression analysis of TRAP showed osteoclast differentiation to be more active on MM. CONCLUSION. Both M and MM have a good effect on osteoblastic cell differentiation, but MM may speed the bone remodeling process by activating on osteoclast differentiation.