• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.39-45
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• 2015

We investigated whether multiple infections can be used as predictors of progression to carcinogenesis in accordance with the cytological diagnosis in women receiving abnormal cytologic diagnosis as analysis genotype and compared to single infection. HPV prevalence is highest in the age of under 30 years old woman, HPV prevalence is started to lower after 30 years old and started to increase over 60 years old as like a U-shape. The specific HPV genotypes is an important factor because increased single infection and reduced multiple infections and appeared single infection with AC in progressing carcinogenesis. HPV 16 revealed the statistical significance at the single infection in squamous cell lesions, and HPV 18 revealed the statistical significance at the single infection in adenocarcinoma with showed HPV 16, 58, 18, 52-type distribution.

• 한국전기화학회:학술대회논문집
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• 1998.12a
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• pp.7-27
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• 1998

In order to design capacity of lithium ion battery, some calculations were carried out based on the characteristics of materials by the given battery shape and dimension. The principle of design was built by the interpretation of the correlation of material, electrochemical and battery factors. Parameters of materials are fundamental physical properties of constituent such as cathode. separator, anode, current collectors and electrolyte. Electrochemical factor includes potential pattern as a function of specific capacity, specific discharge capacity(or initial irreversible specific capacity or Ah efficiency) as a function of specific charge capacity and material balancing. Parameters of battery are dimension, construction hardware and performance. Battery capacity was simulated for a lithium cobalt dioxide as cathode and a hard carbon as anode to achieve 1100 mAh for the charge limit voltage of 4.2V, the weight ratio(+/-) of 2.4 and ICR18650. A fabricated test cell (ICR18650) which have weight ratio(+/-) of 2.4 discharged to 1093 mAh for the charge limit voltage of 4.2V. The sequential discharge capacity show good correspondence with designed capacity.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.6
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• pp.640-647
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• 2012

Current electronic products are dominated by the laser processing and the application will be extended this time. Especially, demands for high precision laser processing with a large area has been increasing for a number of applications such as in solar cell battery, display parts, electronic component and automobile industry. In this paper we designed an on-the-fly system for ultrafast/high precision/large area laser processing. In addition, we have developed the path algorithm for large area. Expansion of the area in which laser processing is an important factor to handle the ultrafast/wide area processing, it will require a processing path. Processing path is path of 2- axis stage and stage of change in velocity can be smooth as possible. We proposed a path of the user concept using NURBS(Non-Uniform Rational B-Spline)method. Through our experiment with the chopper, was to prove the continuity of edge parts. Through basic shape experiments, we proved that large area can be processed using laser. We developed a simulation tool using Visual C++.

• New & Renewable Energy
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• v.16 no.4
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• pp.49-64
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• 2020

Photovoltaic and Thermal collector (PV/T) systems are renewable energy devices that can produce electricity and heat energy simultaneously using solar panels and heat exchangers. Since PV/T systems are exposed to the outdoors, their reliability is affected by various environmental factors. This paper presents a reliability test for a PV/T system and evaluates the test results. The reliability assessment entails performance, environment, safety, and life tests. The factor that had the greatest influence on the life of the system was the hydraulic pressure applied to the heat exchanger. A test was conducted by repeatedly applying pressure to the PV/T system, and a reliability analysis was conducted based on the test results. As a result, the shape parameter (β) value of 5.6658 and the B10life 308,577 cycles at the lower 95% confidence interval were obtained.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.39.1-39.1
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• 2009

NiTi alloy is widely used innumerous biomedical applications (orthodontics, cardiovascular, orthopaedics, etc.) for its distinctive thermomechanical and mechanical properties such as shape memory effect, super elasticity, low elastic modulus and high damping capacity. However, NiTi alloy is still a controversial biomaterial because of its high Ni content which can trigger the risk of allergy and adverse reactions when Ni ion releases into the human body. In order to improve the corrosion resistance of the TiNi alloy and suppress the release of Ni ions, many surface modification techniques have been employed in previous literature such as thermal oxidation, laser surface treatment, sol-gel method, anodic oxidation and electrochemical methods. In this paper, the NiTi was electrochemically etched in various electrolytes to modify surface. The microstructure, element distribution, phase composition and roughness of the surface were investigatedby scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry(EDS), X-ray diffractometry (XRD) and atomic force microscopy (AFM). Systematic controlling of nano and submicron surface features was achieved by altered density of hydro fluidic acid in etchant solution. Nanoscale surface topography, such as, pore density, pore width, pore height, surface roughness and surface tension were extensively analyzed as systematical variables.Importantly, bone forming cell, osteoblast adhesion was increased in high density of hydro fluidic treated surface structures, i.e., in greater nanoscale surface roughness and in high surface areas through increasing pore densities.All results delineate the importance of surface topography parameter (pores) inNiTi to increase the biocompatibility of NiTi in identical chemistry which is crucial factor for determining biomaterials.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.2
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• pp.149-156
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• 1994

Failure of in vitro fertilization may occur even though oocyte and semen parameters seem satisfactory. Quantified ultrastructural study of spermatozoa was performed in three cases of failed in vitro fertilization. The results were compared to those of four fertile men. Quantification was achieved by cataloguing cell defects of the spermatozoon heads and mid/principal pieces of the flagella. Using the data from each specimen, the percentages of total cellular abnormalities in the head/mid/principal pieces were established. The percentages of anomalies of the midpiece and of the principal piece were not significantly different between failed cases and controls. The percentage of cell alterations of the head (96-100 vs 75${\pm}$3,4%), the percentage of combined anomalies of the head (80-86 vs 52.5${\pm}$1.9%), and the percentages of nuclear shape deformation (68-86 vs 47.5${\pm}$6.3%), acrosomal defects (86-96 vs 50${\pm}$4.3%), and postacrosomal sheath defects (78-88 vs 44.5${\pm}$7.2%) of the head were significantly different between failed cases and controls. Due to the cost and time involved in processing semen samples for electron microscopy, the widespread application of this technique to all couples presenting for IVF certainly is not warranted. However, in selected instances electron microscopy may play a crucial role in identifying an occult male factor.

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.106-116
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• 2016

Objective : Protein disulfide isomerase (PDI) acts as a chaperone on the cell surface, and it has been reported that PDI is associated with the tumor cell migration and invasion. The aims of this study are to investigate the anti-migration effect of bacitracin, which is an inhibitor of PDI, and the associated factor in this process. Methods : U87-MG glioma cells were treated with bacitracin in 1.25, 2.5, 3.75, and 5.0 mM concentrations. Western blot with caspase-3 was applied to evaluate the cytotoxicity of bacitracin. Adhesion, morphology, migration assays, and organotypic brain-slice culture were performed to evaluate the effect of bacitracin to the tumor cell. Western blot, PCR, and gelatin zymography were performed to investigate the associated factors. Thirty glioma tissues were collected following immunohistochemistry and Western blot. Results : Bacitracin showed a cytotoxicity in 3rd (p<0.05) and 4th (p<0.001) days, in 5.0 Mm concentration. The cell adhesion significantly decreased and the cells became a round shape after treated with bacitracin. The migration ability, the expression of phosphorylated focal adhesion kinase (p-FAK) and matrix metalloproteinase-2 (MMP-2) decreased in a bacitracin dose- and time-dependent manner. The U87-MG cells exhibited low-invasiveness in the 2.5 mM, compared with the untreated in organotypic brain-slice culture. PDI was expressed in the tumor margin, and significantly increased with histological glioma grades (p<0.001). Conclusion : Bacitracin, as a functional inhibitor of PDI, decreased the phosphorylated FAK and the secreted MMP-2, which are the downstream of integrin and play a major role in cell migration and invasion, might become one of the feasible therapeutic strategies for glioblastoma.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2290-2294
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• 2014

For the present study, rhEGF was encapsulated into solid lipid nanoparticles (SLNs). The SLNs were prepared by the $W_1/O/W_2$ double emulsification method combined with the high pressure homogenization method and the physical properties such as particle size, zeta-potential and encapsulation efficiency were measured. The overall particle morphology of SLNs was investigated using a transmission electron microscopy (TEM). The percutaneous skin permeation and accumulation property of rhEGF was evaluated using Franz diffusion cell system along with confocal laser scanning microscopy (CLSM). The mean particle size of rhEGF-loaded SLNs was $104.00{\pm}3.99nm$ and the zeta-potential value was in the range of -$36.99{\pm}0.54mV$, providing a good colloidal stability. The TEM image revealed a spherical shape of SLNs about 100 nm and the encapsulation efficiency was $18.47{\pm}0.22%$. The skin accumulation of rhEGF was enhanced by SLNs. CLSM image analysis provided that the rhEGF rat skin accumulation is facilitated by an entry of SLNs through the pores of skin.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.535-542
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• 2001

The objective of this study is to develop a spatial analysis modeling technique to evaluate the functional suitability of forest lands for land slide prevention. The functional suitability is classified into 3 categories of high, medium and low according to the potential of land slide on forest lands. The potential of land slide hazards is estimated using the measurements of 7 major site factors : slope, bed rock, soil depth, shape of slope, forest type and D.B.H. class of trees. The analytic hierarchical process is applied to determining the relative weight of site factors in estimating the potential of land slides. The spatial analysis modeling starts building base layers for the 7 major site factors by $25m{\times}25m$ grid analysis or TIN analysis, reclassifies them and produces new layers containing standardized attribute values, needed in estimating land slide potential. To these attributes, applied is the weight for the corresponding site factor to build the suitability classification map by map algebra analysis. Then, finally, cell-grouping operations convert the suitability classification map to the land unit function map. The whole procedures of the spatial analysis modeling are presented in this paper.