• Title/Summary/Keyword: Capillary potential

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Development of the Organic Solar Cell Technology using Printed Electronics (인쇄전자 기술을 이용한 유기 태양전지 기술 개발)

  • Kim, Jungsu;Yu, Jongsu;Yoon, Sungman;Jo, Jeongdai;Kim, Dongsoo
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.113.1-113.1
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    • 2011
  • PEMS (printed electro-mechanical system) is fabricated by means of various printing technologies. Passive and active compo-nents in 2D or 3D such as conducting lines, resistors, capacitors, inductors and TFT(Thin Film Transistor), which are printed withfunctional materials, can be classified in this category. And the issue of PEMS is applied to a R2R process in the manu-facturing process. In many electro-devices, the vacuum process is used as the manufacturing process. However, the vacuum process has a problem, it is difficult to apply to a continuous process such as a R2R(roll to roll) printing process. In this paper, we propose an ESD (electro static deposition) printing process has been used to apply an organic solar cell of thin film forming. ESD is a method of liquid atomization by electrical forces, an electrostatic atomizer sprays micro-drops from the solution injected into the capillary with electrostatic force generated by electric potential of about several tens kV. ESD method is usable in the thin film coating process of organic materials and continuous process as a R2R manufacturing process. Therefore, we experiment the thin films forming of PEDOT:PSS layer and active layer which consist of the P3HT:PCBM. The organic solar cell based on a P3HT/PCBM active layer and a PEDOT:PSS electron blocking layer prepared from ESD method shows solar-to-electrical conversion efficiency of 1.42% at AM 1.5G 1sun light illumination, while 1.86% efficiency is observed when the ESD deposition of P3HT/PCBM is performed on a spin-coated PEDOT:PSS layer.

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Comparison of Doppler and CT Angiography as a Predictor of Healing Diabetic Foot Ulcers (당뇨발 치유 가능성의 예측을 위한 도플러와 CT 혈관조영술의 비교)

  • Park, Doug-John;Kim, Hyon-Surk;Han, Seung-Kyu;Kim, Hee-Young;Chun, Kyung-Wook;Kim, Woo Kyung
    • Archives of Plastic Surgery
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    • v.35 no.5
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    • pp.495-500
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    • 2008
  • Purpose: Adequate tissue oxygenation is considered as an essential factor for wound healing. In the non-diabetic population, an uncompromised macrocirculation generally leads to adequate tissue oxygenation. On the contrary, the macrocirculation in diabetic patients may not correlate with tissue oxygenation because of structural changes in the capillary basement membrane. Nevertheless, many medical professionals in Korea rely on macrocirculation evaluation when predicting wound healing potential of the diabetic ulcers. The purpose of this study is to compare reliability of two common macrocirculation assessment methods, Doppler probing and CT angiography, on tissue oxygenation in diabetic foot patients. Methods: Doppler and CT angiography scores were given according to the patency of the anterior and posterior tibial arteries. Tissue oxygenation was measured by transcutaneous partial oxygen tension($TcpO_2$). Doppler and CT angiography scores were statistically analyzed against $TcpO_2$ values. Sixty-eight diabetic foot ulcer patients were included in this study. Results: The test was carried out on Doppler score and $TcpO_2$ variables displayed a p-value of 0.0202, and concluded that the two variables were statistically dependent. The test used to determine for linear trends between Doppler scores and $TcpO_2$ variables displayed a p-value of 0.0149, displaying statistical linear trend between the two variables. On the contrary, the tests between CT angiography scores and $TcpO_2$ variables showed p-values of 0.1242 and 0.6590, that means no correlation between CT angiography and $TcpO_2$ scores. Conclusion: Doppler probing is more reliable than CT angiography in predicting tissue oxygenation of diabetic foot ulcers.

Analytic Model for Predicting the Permeability of Foam-type Wick (폼 타입 윅의 투과도를 예측하기 위한 해석 모델)

  • Ngo, Ich-Long;Byon, Chan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.6
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    • pp.391-396
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    • 2016
  • Wicks play an important role in determining the thermal performance of heat pipes. Foam-type wicks are known to have good potential for enhancing the capillary performance of conventional types of wicks, and this is because of their high porosity and permeability. In this study, we develop an analytic expression for predicting the permeability of a foam-type wick based on extensive numerical work. The proposed correlation is based on the modified Kozeny-Carman's equation, where the Kozeny-Carman coefficient is given as an exponential function of porosity. The proposed correlations are shown to predict the previous experimental results well for an extensive parametric range. The permeability of the foam-type wick is shown to be significantly higher than that of conventional wicks because of their high porosity.

Effects of Glucosamine Hydrochloride, Taurine and Their Combined Administration on Anti-inflammatory and Analgesic Action in Rats (흰쥐의 항염증 및 진통작용에 대한 Glucosamine Hydrochloride와 Taurine 및 그 혼합 투여시의 효과)

  • 김옥경
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1113-1123
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    • 1999
  • The purpose of this study was to see the effect of anti inflammatory and analgesic action of the glucosamine hydrochloride(GA HCl) or taurine. Male Sprague Dawley rats(100~250g) and ICR mice(20 ~30g) were used. Experimental groups were divided into seven groups, one control group given as saline and six groups given as oral administration of GA HCl or taurine; GA HCl 250mg/kg, b.w group, taurine 250mg/kg, b.w group, GA HCl 250mg/kg, b.w+taurine 250mg/kg, b.w group, GA HCl 500mg/kg, b.w group, taurine 500mg/kg, b.w group, GA HCl 500mg/kg, b.w+taurine 500mg/kg, b.w group. Carrageenan induced edema test were shown to be significantly inhibited in the GA HCl 250mg/kg group and taurine 250mg/kg group compared to the control group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Capillary permeability test were shown to be sig nificantly inhibited in the taurine 500mg/kg group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Leucocyte emigration test were shown to be significantly inhibited in the GA HCl 250mg/kg+ taurine 250mg/kg group and GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Acetic acid, Phenyl p benzoquinone writhing syndrome were shown to be significantly inhibited in the GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Inhibitory action against COX 1 and COX 2 were not significantly inhibited in the experimental group. These results suggest that the combined administration of the GA HCl and taurine have potential action in anti inflammatory and analgesic action.

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Anti-inflammatory Effects of Hataedock with Douchi in Atopic Dermatitis-like Skin Lesions in House Dust Mite-Induced NC/Nga Mice (PKC 활성 조절을 통한 두시 하태독법의 항염증작용이 Mite 항원 유도 아토피유사피부염 발병 조절에 미치는 효과)

  • Ahn, Sang Hyun;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.30 no.4
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    • pp.77-86
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    • 2016
  • Objectives Hataedock (HTD) is an oral Korean herbal medical oral treatment that removes fetal toxic heat and meconium from new born babies. The purpose of this study is to evaluate whether Hataedock treatment of Duchi extracts has anti-inflammation effects in atopic dermatitis-like skin lesions in House Dust Mite-Induced NC/Nga Mice. Methods The mice were divided into 3 groups (n=10 per group) as follows: the control group (Ctrl group), AD-induced group (AE group), AD-induced with HTD treatment group (DT group). 3-week-old NC/Nga mice were introduced to Hataedock treatment, made of Duchi extract. After 4 weeks, House Dust Mite-Induced application was used six times per week for 3 weeks to induce the first atopic dermatitis, and second AD in 7 weeks after. To examine skin injuries and anti-inflammatory effect, PKC, MMP-9, iNOS immunohistochemistry were used. Results The alleviate effect of the skin damage and angiogenesis was observed in DT group. The damage of stratum corneum, hyperplasia, edema, infiltration of lymphocytes and distribution of capillary were decreased in DT group. Also, the study results suggested that Hataedock treatment made of Duchi extracts in DT group remarkably decreased skin damages by 51% (p < 0.001), as well as PKC by 91%, MMP-9 by 48% (p < 0.001), iNOS by 51% (p < 0.001). Conclusions Based on the study results, we observed that Hataedock treatment of Duchi extracts alleviates AD by diminishing various inflammatory cytokines, initial steps of AD development, in the skin lesions. Potential applications for prevention and treatment of atopic dermatitis are expected.

ANTI-TUMOR EFFECTS OF VASCULAR ENDOTHELIAL GROWTH FACTOR INHIBITOR ON ORAL SQUAMOUS CELL CARCINOMA CELL LINES (혈관내피세포성장인자 억제제에 의한 구강편평상피세포암종 세포주의 성장 억제 효과)

  • Han, Se-Jin;Lee, Jae-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.35 no.2
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    • pp.66-73
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    • 2009
  • Tumor angiogenesis is a process leading to formation of blood vessels within tumors and is crucial for maintaining a supply of oxygen and nutrients to support tumor growth and metastasis. Vascular endothelial growth factor(VEGF) plays a key role in tumor angiogenesis including induction of endothelial cell proliferation, migration, survival and capillary tube formation. VEGF binds to two distinct receptors on endothelial cells. VEGFR-2 is considered to be the dominant signaling receptor for endothelial cell permeability, proliferation, and differentiation. Bevacizumab(Avastin, Genetech, USA) is a monoclonal antibody against vascular endothelial growth factor. It is used in the treatment of cancer, where it inhibits tumor growth by blocking the formation of new blood vessels. The goal of this study is to identify the anti-tumor effect of Bevacizumab(Avastin) for oral squamous cell carcinoma cell lines. Human squamous cell carcinoma cell line(HN4) was used in this study. We examined the sensitivity of HN4 cell line to Bevacizumab(Avastin) by using in vitro proliferation assays. The results were as follows. 1. In the result of MTT assay according to concentration of Bevacizumab(Avastin), antiproliferative effect for oral squamous cell carcinoma cell lines was observed. 2. The growth curve of cell line showed the gradual growth inhibition of oral squamous cell carcinoma cell lines after exposure of Bevacizumab(Avastin). 3. In the apoptotic index, groups inoculated Bevacizumab(Avastin) were higher than control groups. 4. In condition of serum starvation, VEGFR-2 did not show any detectable autophosphorylation, whereas the addition of VEGF activated the receptor. Suppression of phosphorylated VEGFR-2 and phosphorylated MAPK was observed following treatment with Bevacizumab(Avastin) in a dose-dependent manner. 5. In TEM view, dispersed nuclear membrane, scattered many cytoplasmic vacuoles and localized chromosomal margination after Bevacizumab(Avastin) treatment were observed. These findings suggest that Bevacizumab(Avastin) has the potential to inhibit MAPK pathway in proliferation of oral squamous cell carcinoma cell lines via inhibition of VEGF-dependent tumor growth.

The Anti-inflammatory Effects of Hataedock Taken Douchi Extracts on Atopic Dermatitis-like Skin Lesion of NC/Nga Mouse (두시(豆豉) 추출물을 이용한 하태독법(下胎毒法)이 NC/Nga 생쥐에서 유발된 아토피 유도 피부염에 미치는 항염증 효과)

  • Aum, Sun Ho;Ahn, Sang Hyun;Park, Sun Young;Cheon, Jin Hong;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.30 no.2
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    • pp.1-9
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    • 2016
  • Objectives Hataedock is a Korean herbal medical oral treatment that removes fetal toxic heat and meconium from new born babies. The purpose of this study is to evaluate whether Hataedock treatment of Duchi extracts has anti-inflammation effects on AD (Atopic Dermatitis)-induced NC/Nga mice. Methods After Hataedock treatment of Duchi extracts on days 0, 3-week-old NC/Nga mice were sensitized on days 28, 35, 42 by exposure of DNFB (dinitrochlorobenzene) and were induced to have AD. Immunohistochemistry of NF-${\kappa}B$ p65, iNOS, COX-2 and TUNEL assay of apoptotic body was used to identify changes of skin damages and anti-inflammation effects. Results The alleviate effect of the skin damage and angiogenesis was observed in DT group. The damage of stratum corneum, hyperplasia, edema, infiltration of lymphocytes and distribution of capillary were decreased in DT group. Also, the study results suggested that Hataedock treatment of Duchi extracts in DT group remarkably downregulated levels of NF-${\kappa}B$ p65 by 70% (p < 0.001), as well as COX-2 by 51%, iNOS by 62% (p < 0.001). Additionally, Hataedock treatment of Duchi extracts in DT group up-regulated apoptosis of inflammatory cells by 68% in atopic dermatitis-like skin lesion. Conclusions From the study results, we observed that Hataedock treatment of Duchi extracts alleviates AD through diminishing various inflammatory cytokines in the skin lesions, which are involved in the initial steps of AD development. It is anticipated to have potential applications for prevention and treatment of atopic dermatitis.

Study on Antiangiogenic Effect of Black Ginseng Radix (흑삼의 신생혈관 억제활성에 대한 연구)

  • Song, Gyu-Yong;Chung, Kyu-Jin;Shin, Young-Jin;Lee, Gye-Won;Lee, Sook-Young;Seo, Young-Bae
    • The Korea Journal of Herbology
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    • v.26 no.3
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    • pp.83-90
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    • 2011
  • Objectives : This study was performed to investigate the influence of black ginseng radix extracts (BG) and ginsenoside Rg3, Rg5 on basic fibroblast growth factor (bFGF) induced proliferation, migration and capillary tubule-like formation of human umbilical vein endothelial cells (HUVECs). Methods : HUVECs were cultured with BG and ginsenoside Rg3, Rg5 at different concentrations (60, 125, 250, 500, $1,000{\mu}g/m\ell$) for 2 day In the presence of bFGF, respectively. XTT was used to detect the proliferation. Migration and tube formations were examined to detect the antiangiogenesis. Also, the chick embryo chorioallantoic membrane (CAM) assay was performed to detect the antiangiogenesis. Results : BG and ginsenoside Rg3, Rg5 significantly inhibited bFGF-induced endothelial cell proliferation and migration in a dose-dependent manner. Tube formation in bFGF-induced HUVECs were suppressed by BG and ginsenoside Rg3, Rg5. Moreover, BG and ginsenoside Rg3, Rg5 (30-$50{\mu}g$/egg) inhibited new blood vessel formation on the growing CAM. Conclusions:Based on the present results, it can be suggested that BG has a potential chemopreventive agent via antiangiogenesis.

A COMPARATIVE STUDY OF WOUND HEALING AFTER SKIN INCISION WITH SCALPEL, $CO_2$, AND Nd:YAG LASER IN RATS (수술칼, $CO_2$ 및 Nd:YAG 레이저에 의한 절개 창상의 치유에 관한 비교 연구)

  • Choi, Jae-Sun;Ryu, Sun-Youl
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.1
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    • pp.33-42
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    • 2000
  • The purpose of this study was to compare the wound healing process after skin incision using scalpel, $CO_2$ laser and pulsed Nd:YAG laser in rats. After skin on the back was incised 3 cm long, rats were sacrificed at 1, 3, 7, 14, 21 and 28 days. Macroscopic, histologic and immunohistochemical examinations using the collagen type IV and the CD34 antibodies which are necessary to the forming process of new capillary were performed. Results obtained were as follows ; Macroscopically the initial wound healing of the laser group was about $1{\sim}2$ weeks slower than that of the scalpel group. There weren't however any remarkable differences in all groups in 4 weeks after incision. By histologic finding, acute inflammatory cells were more prominent during the initial wound healing in the scalpel group than in the other groups. Epithelialization started in the order of scalpel, $CO_2$ and Nd:YAG laser group after skin incision. By the Masson's trichrome stain, collagen synthesis in the Nd:YAG laser group was more slowly initiated than in the other groups. But it was completed at the $3{\sim}4$ weeks in all groups. Immunohistochemically, collagen type IV and CD34 expression were markedly increased at 2 weeks in the scalpel and $CO_2$ laser group. Meanwhile, in the Nd:YAG laser group, these reactions were observed later tan the other groups. Collagen type IV and CD34 expression were decreased in all groups after 4 weeks. These results suggest that $CO_2$ and Nd:YAG laser showed similar healing process compared with scalpel and a potential substitute for scalpel in skin incision.

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Effect of Acetylcholine on Electrical Activity of Cat Stomach (자율신경계에 작용하는 약물이 위장 전기도에 미치는 영향)

  • Kim, Myung-Suk;Park, Hyoung-Jin;Bai, Sun-Ho;Choi, Hyun;Kim, Chul
    • The Korean Journal of Physiology
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    • v.14 no.2
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    • pp.21-28
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    • 1980
  • In order to investigate the effect of cholinergic substance on the electrical and the mechanical activities of the stomach muscle, 10 isolated cat stomachs were studied. At various sites of a stomach muscle preparation, the electrical activity was monopolarly recorded by using capillary electrodes containing chlorided silver wires, and the isometric contractile activity was recorded simultaneously at the terminal portion of the antrum in Krebs solution$(36^{\circ}C)$ which was aerated with a gas mixture consisting of 95% $O_2$ and 5% $CO_2$. The recording of these activities were performed before (control period) and after acetylcholine$(10^{-5}M)$ and atropine $(10^{-6}M)$ administrations serially. Following results were obtained: 1) The mean frequency of the slow wave was $4.36{\pm}0.22\;cycles/min$ at all the various sites of the cat stomach. The slow wave was propagated caudad in sequence and its velosity of propagation increased as the slow wave approached the pylorus in normal Krebs solution. 2) After acetylcholine administration, the frequency of the slow wave increased transiently and the increase of slow wave frequency was followed by the isometric contraction of antral muscle in association with the second potential which succeeded the slow wave. 3) By atropine administration, the stimulatory effect of acetylcholine on the antral muscle contraction was abolished completely, and the frequency of the slow wave decreased significantly compared with that of the control period, which tendency was more prominent in the antrum. The above results suggest that the transient increase in the frequency of gastric slow wave by acetylcholine may have some influence upon the contraction mechanism of the cat antral muscle.

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