• Title/Summary/Keyword: light-time effect

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Effects of Electrical Stimulation on Wound Healing and Skin Mast Cells in Streptozotocin-Induced Diabetic Rats (스트렙토조토신 유도 당뇨 흰쥐에서 전기자극이 상처치유와 피부 비만세포에 미치는 영향)

  • Jekal, Seung-Joo;Lee, Kyung-Sun;Chung, Ok-Bong;Lee, Jae-Hyoung
    • Korean Journal of Clinical Laboratory Science
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    • v.40 no.2
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    • pp.118-128
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    • 2008
  • The aim of this study was to investigate the effect of electrical stimulation on healing of impaired wound and alteration of mast cells in experimental diabetic rats. Thirty male Sprague-Dawley rats were divided into three groups : incision (control), diabetes+incision (diabetes) and diabetes + incision + electrical stimulation (D/ES). Diabetes was induced in rats by streptozotocin (STZ) injection (60 mg/kg, one time) and 20 mm length incision wounds were created on the back after shaving hair. The electrical stimulation rats were treated with a current intensity of 30~50 V at 120 pps and $140{\mu}s$ for 10 days from 3 days after STZ injection. The lesion and adjacent skin tissues were fixed with 10% buffered formalin, embedded with paraffin. For wound healing analysis, hematoxylin-eosin (HE) and picrosirius red staining were performed. Mast cells (MC) were stained with toluidine blue (pH 0.5) and quantified at ${\times}200$ using a light microscope. The density of keratinocyte proliferation and microvessels in skin tissues were analyzed using a computerized image analysis system on sections immunostained with proliferative cell nuclear antigen (PCNA) and ${\alpha}$-smooth muscle actin (${\alpha}$-SMA), respectively. The results showed that the wound healing rate, collagen density and neoepidermis thickness, density of PCNA-positive cells and density of ${\alpha}$-SMA-positive vessels were significantly higher in D/ES rats than in diabetic rats. The density of MCs and degranulated MCs in D/ES rats were also significantly higher than those in diabetic rats. These findings suggest that the electrical stimulation may promote the tissue repair process by accelerating collagen production, keratinocyte proliferation and angiogenesis in the diabetic rats, and MCs are required for wound healing of skin in rats.

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Establishment of Long-term Storage Condition of Fresh Red Pepper Paste (생홍고추 페이스트의 장기 저장조건 설정)

  • Kwon, Dong-Jin;Jo, Jin-Ho;Kim, Hyun-Ku;Park, Mu-Hyun
    • Korean Journal of Food Science and Technology
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    • v.22 no.4
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    • pp.415-420
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    • 1990
  • To prevent red pepper from post harvest decay and to reduce the labor and drying expenses, the red pepper paste was directly prepared from fresh red pepper. The characteristics of red pepper paste and processing properties were investigated, and the effect of salt and heat on product quality during processing and storage were studied. After the processed red pepper paste was stored at room temperature, $5^{\circ}C\;and\;-3^{\circ}C$ without light for 6 months, kimchi was prepared with the stored red pepper paste to evaluate any quality change. The weight and pH of pericarp were 73.2% of total and 5.0, respectively. Addition of 10% salt to the paste decreased the pH of paste, reducing the sterilization time down to 10 min against growth of Clostridium botulinum. Thermal diffusivity of paste after pasteurization was $1.190{\times}10cm^{-7}/sec$, which was lower than control, probably due to air in pouch. The red pepper paste with 10% salt added, followed by sterilization for 10 min, could be preserved for over 6 months at $5^{\circ}C$.

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PDMS-based pixel-wall bonding technique for a flexible liquid crystal display (플렉서블 액정 디스플레이를 위한 PDMS 기반 pixel-wall bonding 기술)

  • Kim, Young-Hwan;Park, Hong-Gyu;Oh, Byeong-Yun;Kim, Byoung-Yong;Paek, Kyeong-Kap;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.04a
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    • pp.42-42
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    • 2008
  • Considerable attention has been focused on the applications of flexible liquid crystal (LC)-based displays because of their many potential advantages, such as portability, durability, light weight, thin packaging, flexibility, and low power consumption. To develop flexible LCDs that are capable of delivering high-quality moving images, like conventional glass-substrate LCDs, the LC device structure must have a stable alignment layer of LC molecules, concurrently support uniform cell gaps, and tightly bind two flexible substrates under external tension. However, stable LC molecular alignment has not been achieved because of the layerless LC alignment, and consequently high-quality images cannot be guaranteed. To solve these critical problems, we have proposed a PDMS pixel-wall based bonding method via the IB irradiation was developed for fasten the two substrates together strongly and maintain uniform cell gaps. The effect of the IB irradiation on PDMS with PI surface was also evaluated by side structure configuration and a result of x-ray photoelectron spectroscopic analysis of PDMS interlayer as a function of binder with substrates. large number of PDMS pixel-walls are tightly fastened to the surface of each flexible substrate and could maintain a constant cell gap between the LC molecules without using any other epoxy or polymer. To enhance the electro-optical performance of the LC device, we applied an alignment method that creates pretilt angle on the PI surface via ion beam irradiation. Using this approach, our flexible LCDs have a contrast ratio of 132:1 and a response time of about 15 ms, resulting in highly reliable electro-optical performance in the bent state, comparable to that of glass-substrate LCDs.

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Generalization of Vertical Plume Despersion in the concective Boundary Layer at Long Distances on Mesoscale (중거리에서 대류경계층 연직방향 plume 확산의 일반화)

  • 서석진
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.2
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    • pp.141-150
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    • 2000
  • In order to genralize the vertical dispersion of plume at long distances on mesoscale over complex terrain dispersion coefficients data have been obtained systematically according to lapsed time after release by using a composite turbulence water tank that simulates convective boundary layer. Dispersion experiments have been carried out for various combined conditions of thermal turbulence intensity mechanical turbulence intensity and plume release height at slightly to moderately unstable conditions. Results of tracer dispersion experiments conducted using water tank camera and image processing system have been converted into atmospheric dispersion data through the application of similarity law. The equation $\sigma$z/Zi=aX/(b+c X2)0.5 where $\sigma$2; vertical dispersion coefficient zi : mixing height X : dimen-sionaless downwind distance was confirmed to be an appropriate and general equation for expressing $\sigma$2 variation with turbulence intensity and plume release height, The value of "a" was found to be principally affected by mechanical turbulence intensity and that of "b" by mechanical turbulence intensity and release height. It was confirmed that the magnitude of "c" varies with release height. Results of water tank experiments on the relationship of $\sigma$2 vs downwind distance x have been compared with actual atmospheric dispersion data such as CONDORS data and Bowne's nomogram Operating conditions of a composite turbulence water tank for simulating the field turbulence situations of CONDORS experiments and Bowne's $\sigma$2(x) nomogram for suburban area have also been investigated in terms of water temperature difference between convection water tank and bottom plate heating tank grid plate stroke mixing water depth length scale and velocity scale. Moreover the effect of mechanical turbulence intensity on vertical dispersion has been discussed in the light of release height and downwind distance. height and downwind distance.

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Flocculation Effect of Alkaline Electrolyzed Water (AEW) on Harvesting of Marine Microalga Tetraselmis sp.

  • Lee, Su-Jin;Choi, Woo-Seok;Park, Gun-Hoo;Kim, Tae-Ho;Oh, Chulhong;Heo, Soo-Jin;Kang, Do-Hyung
    • Journal of Microbiology and Biotechnology
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    • v.28 no.3
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    • pp.432-438
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    • 2018
  • Microalgae hold promise as a renewable energy source for the production of biofuel, as they can convert light energy into chemical energy through photosynthesis. However, cost-efficient harvest of microalgae remains a major challenge to commercial-scale algal biofuel production. We first investigated the potential of electrolytic water as a flocculant for harvesting Tetraselmis sp. Alkaline electrolyzed water (AEW) is produced at the cathode through water electrolysis. It contains mineral ions such as $Na^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ that can act as flocculants. The flocculation activity with AEW was evaluated via culture density, AEW concentration, medium pH, settling time, and ionic strength analyses. The flocculation efficiency was 88.7% at 20% AEW (pH 8, 10 min) with a biomass concentration of 2 g/l. The initial biomass concentration and medium pH had significant influences on the flocculation activity of AEW. A viability test of flocculated microalgal cells was conducted using Evans blue stain, and the cells appeared intact. Furthermore, the growth rate of Tetraselmis sp. in recycled flocculation medium was similar to the growth rate in fresh F/2 medium. Our results suggested that AEW flocculation could be a very useful and affordable methodology for fresh biomass harvesting with environmentally friendly easy operation in part of the algal biofuel production process.

Effect and Mechanism of Glutamine on Productive Performance and Egg Quality of Laying Hens

  • Dong, Xiao-Ying;Yang, Chu-Fen;Tang, Sheng-Qiu;Jiang, Qing-Yan;Zou, Xiao-Ting
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.8
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    • pp.1049-1056
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    • 2010
  • This study was conducted to investigate the effects of dietary glutamine (Gln) on the productive performance and egg quality of laying hens. A total of four hundred Lingnan Yellow laying hens aged 34 weeks were randomly assigned into four groups (100 laying hens/group), and fed, respectively, with diets supplemented with 0% (control group), 0.2%, 0.4%, and 0.8% Gln during the 6-week feeding period. The results were as follows. First, the productivity of laying hens fed with 0.8% Gln in diet was significantly increased (p<0.05); however, the egg quality (egg weight, yolk weight, shell weight, egg shape index, shell thickness, shell density, shell breaking strength, yolk color, yolk index, and Haugh unit) was not affected compared with that of the control group (p>0.05). Second, luteinizing hormone (LH) (p<0.01), follicle stimulating hormone (FSH) (p<0.01), triiodothyronine ($T_3$), and tetraiodothyronine ($T_4$) contents (p<0.05) in blood of laying hens fed with 0.8% Gln in diets were also significantly improved, and greater improvement in the duodenum and oviduct structure was observed in that treatment group. This study indicated for the first time that diets with 0.8% Gln were able to increase the productive performance of laying hens through stimulating hormone secretion and better development of both the duodenum and oviduct structure in laying hens.

Phenomenological Modeling of Newly Discovered Eclipsing Binary 2MASS J18024395 + 4003309 = VSX J180243.9+400331

  • Andronov, Ivan L.;Kim, Yonggi;Kim, Young-Hee;Yoon, Joh-Na;Chinarova, Lidia L.;Tkachenko, Mariia G.
    • Journal of Astronomy and Space Sciences
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    • v.32 no.2
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    • pp.127-136
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    • 2015
  • We present a by-product of our long term photometric monitoring of cataclysmic variables. 2MASS J18024395 +4003309 = VSX J180243.9 +400331 was discovered in the field of the intermediate polar V1323 Her observed using the Korean 1-m telescope located at Mt. Lemmon, USA. An analysis of the two-color VR CCD observations of this variable covers all the phase intervals for the first time. The light curves show this object can be classified as an Algol-type variable with tidally distorted components, and an asymmetry of the maxima (the O'Connell effect). The periodogram analysis confirms the cycle numbering of Andronov et al. (2012) and for the initial approximation, the ephemeris is used as follows: Min I. BJD = 2456074.4904+0.3348837E. For phenomenological modeling, we used the trigonometric polynomial approximation of statistically optimal degree, and a recent method "NAV" ("New Algol Variable") using local specific shapes for the eclipse. Methodological aspects and estimates of the physical parameters based on analysis of phenomenological parameters are presented. As results of our phenomenological model, we obtained for the inclination $i=90^{\circ}$, $M_1=0.745M_{\odot}$, $M_2=0.854M_{\odot}$, $M=M_1+M_2=1.599M_{\odot}$, the orbital separation $a=1.65{\cdot}10^9m=2.37R_{\odot}$ and relative radii $r_1=R_1/a=0.314$ and $r_2=R_2/a=0.360$. These estimates may be used as preliminary starting values for further modeling using extended physical models based on the Wilson & Devinney (1971) code and it's extensions

Classification of Tumor cells in Phase-contrast Microscopy Image using Fourier Descriptor (위상차 현미경 영상 내 푸리에 묘사자를 이용한 암세포 형태별 분류)

  • Kang, Mi-Sun;Lee, Jeong-Eom;Kim, Hye-Ryun;Kim, Myoung-Hee
    • Journal of Biomedical Engineering Research
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    • v.33 no.4
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    • pp.169-176
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    • 2012
  • Tumor cell morphology is closely related to its migratory behaviors. An active tumor cell has a highly irregular shape, whereas a spherical cell is inactive. Thus, quantitative analysis of cell features is crucial to determine tumor malignancy or to test the efficacy of anticancer treatment. We use 3D time-lapse phase-contrast microscopy to analyze single cell morphology because it enables to observe long-term activity of living cells without photobleaching and phototoxicity, which is common in other fluorescence-labeled microscopy. Despite this advantage, there are image-level drawbacks to phase-contrast microscopy, such as local light effect and contrast interference ring. Therefore, we first corrected for non-uniform illumination artifacts and then we use intensity distribution information to detect cell boundary. In phase contrast microscopy image, cell is normally appeared as dark region surrounded by bright halo ring. Due to halo artifact is minimal around the cell body and has non-symmetric diffusion pattern, we calculate cross sectional plane which intersects center of each cell and orthogonal to first principal axis. Then, we extract dark cell region by analyzing intensity profile curve considering local bright peak as halo area. Finally, we calculated the Fourier descriptor that morphological characteristics of cell to classify tumor cells into active and inactive groups. We validated classification accuracy by comparing our findings with manually obtained results.

Real 3-D Shape Restoration using Lookup Table (룩업 테이블을 이용한 물체의 3-D 형상복원)

  • Kim, Kuk-Se;Lee, Jeong-Gi;Song, Gi-Beom;Kim, Choong-Won;Lee, Joon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.5
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    • pp.1096-1101
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    • 2004
  • The 3-D shape use to effect of movie, animation, industrial design, medical treatment service, education, engineering etc.... But it's not easy to make 3-D shape from the information of 2-D image. There are two methods in restoring 3-D video image through 2-D image; First the method of using a laser; Secondly the method of acquiring 3-D image through stereo vision. Instead of doing two methods with many difficulties, I figure out the method of simple 3-D image in this research paper. We present here a simple and efficient method, called direct calibration, which doesn't require any equations at all. The direct calibration procedure builds a lookup table(LUT) linking image and 3-D coordinates by a real 3-D triangulation system. The LUT is built by measuring the image coordinates of a grid of known 3-D points, and recording both image and world coordinates for each point; the depth values of all other visible points are obtained by interpolation.

Implementation of Image Enhancement Algorithm for Embedded System (임베디드 시스템을 위한 영상 개선 알고리즘 구현)

  • An, Jeong-yeon;Rhee, Sang-Burm
    • The KIPS Transactions:PartA
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    • v.16A no.6
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    • pp.473-480
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    • 2009
  • This paper is to enhance a color image running in the PXA255 ARM processor based on embedded linux environments. Retinex is one of the representative algorithm for image enhancement in the previous research. However, retinex is not suitable the run on the embedded system because of its long processing time. So, we proposed the image enhancement algorithm for embedded system, with less quantity of operation and the effect equivalent to retinex. To achieve this goal, we propose and implement the image enhancement algorithm, which utilizes the image formation model and gamma correction to be effective in a back-light and dark image. The proposed algorithm converts the color space from RGB to HSV, and then V and S channels are processed. In order to optimize the proposed method in the PXA255 ARM processor, quantity of calculation is reduced. The performance of the proposed algorithm was evaluated through qualitative method and quantitative method. The results show that brightness and contrast are improved with less quantity of operation.