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Effect of polymer substrates on nano scale hot embossing (나노 사이즈 hot embossing 공정시 폴리머의 영향)

  • Lee, Jin-Hyung;Kim, Yang-sun;Park, Jin-goo
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.11a
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    • pp.71-71
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    • 2003
  • Hot embossing has been widely accepted as an alternative to photolithography in generating patterns on polymeric substrates. The optimization of embossing process should be accomplished based on polymer substrate materials. In this paper, the effect of polymer substrates on nano scale hot embossing process was studied. Silicon molds with nano size patterns were fabricated by e-beam direct writing. Molds were coated with self-assembled monolayer (SAM) of (1, 1, 2.2H -perfluorooctyl)-trichlorosilane to reduce the stiction between mold and substrates. For an embossing, pressure of 55, 75 bur, embossing time of 5 min and temperature of above transition temperature were peformed. Polymethylmethacrylates (PMMA) with different molecular weights of 450,000 and 950,000, MR-I 8010 polymer (Micro Resist Technology) and polyaliphatic imide copolymer were applied for hot embossing process development in nano size. These polymers were spun coated on the Si wafer with the thickness between 150 and 200 nm. The nano size patterns obtained after hot embossing were observed and compared based on the polymer properties by scanning electron microscopy (SEM). The imprinting uniformity dependent on the Pattern density and size was investigated. Four polymers have been evaluated for the nanoimprint By optimizing the process parameters, the four polymers lead to uniform imprint and good pattern profiles. A reduction in the friction for smooth surfaces during demoulding is possible by polymer selection.

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Effect of YCT on Insulin Secretion in RIN-m5F Cells (RIN-m5F 세포에서 야관청혈탕(夜關淸血湯)이 인슐린 분비에 미치는 영향)

  • Kim, Jin-Mi;Cho, Chung-Sik;Kim, Chul-Jung
    • The Journal of Korean Medicine
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    • v.31 no.4
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    • pp.20-37
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    • 2010
  • Objective: This study was performed to investigate the effect of Yagwan-cheunghyeoltang (YCT) on insulin secretion in RIN-m5F cells. Methods: After treatment with various concentrations of YCT to RIN-m5F cells, cell viability, free radical-scavenging activity, SOD activity, and insulin secretion were measured. Additionally, insulin-related gene expressions were measured using real-time RT-PCR. Results: 1. YCT didn't show any influence on RIN-m5F cells viability. 2. YCT showed free radical-scavenging activity by 16% at $100{\mu}g/m{\ell}$ of concentration. 3. YCT showed enhancement of SOD activity by 60% at $100{\mu}g/m{\ell}$ of concentration. 4. YCT significantly increased insulin secretion in RIN-m5F cells in a dose-dependent manner. 5. YCT up-regulated INS-1, INS-2, IRS-1, IRS-2 and IRS-3 mRNA expressions compared to the control group. 6. YCT down-regulated INS-R, GCK, GLP-1R and GLP-2R mRNA expressions compared to the control group. Conclusion: YCT has pharmaceutical properties enhancing insulin production and controlling glucose-associated metabolism, and could be a candidate for drug development after further research.

Apoptotic Effect of Phellodendri Cortex Water Extract on MIA PaCa-2 Cells (췌장암 세포주 MIA PaCa-2에서 황백 물 추출물에 의한 Apoptosis 유도 및 작용기전)

  • Lee, In Young;Jeong, Hwang San;Won, Jin Hee
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.2
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    • pp.202-211
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    • 2013
  • The purpose of this study is to investigate the apoptotic effect of Phellodendri Cortex water extract (PCWE) on pancreatic cancer cells and to find out the regulating mechanisms. Human-derived pancreatic cancer cell line, MIA PaCa-2 cells were treated by PCWE with various concentrations and the cytotoxicity was determined by MTT assay. The activation of Annexin V, DNA fragmentation, cell cycle arrest and caspase activation were observed to investigate the role of PCWE in pancreatic cancer cells. Also, to find out the regulating mechanisms, we examined the ROS production. The treatment of PCWE induced the cell death in both concentration and time dependent manner. The treatment of PCWE also increased the expression of Annexin V, DNA fragmentation, cell cycle arrest, and cleavage of caspase, which means cell-death PCWE induced was apoptosis but not necrosis. The ROS production was increased by PCWE treatment and the blockade of ROS inhibited the PCWE-induced cell death. These results could suggest that PCWE induced apoptosis via ROS release in pancreatic cancer cell.

Preventive Effects of Sihosamultang Extract on Lipid Peroxidation by Free Radicals and Oxidative Damage of Hepatocytes by tert-Butyl Hydroperoxide (시호사물탕이 t-BHP로 유도된 간세포의 산화적 손상 및 자유기에 의한 지질과산화 반응에 미치는 영향)

  • Kim Tae-Gi;Park Sun-Dong;Moon Jin-Young
    • Herbal Formula Science
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    • v.8 no.1
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    • pp.241-255
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    • 2000
  • Sihosamultang(SST) has been used for the treatment of puerperal fever, liver disease in traditional medicine. The present study was carried out to evaluate the antioxidant effects of SST extract in vitro. The inhibitory effect of SST extract on lipid peroxidant was examined in the linoleic acid autoxidation system. In this test, SST extract significantly inhibited the time course of the lipid peroxidation. And SST extract showed about 73% scavenging effect on DPPH radical. And this extract inhibited not only the lipid peroxide formation induced by hydroxyl radical derived from $ H_{2}O_{2}-Fe^{2+}$ in the rat liver homogenate, but also the superoxide generation from xanthine-xanthine oxidase system in a dose-dependent manner. In addition, SST extract protected the hepatic cell death induced by tert-butyl hydroperoxide. These data indicated that SST might play a protective role against oxidative injury by free radicals.

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Effects of Drynariae Rhizoma on the Proliferation of Human Bone Cells

  • Lee, Bu-Tae;Jeong, Ji-Cheon
    • The Journal of Korean Medicine
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    • v.24 no.4
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    • pp.43-53
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    • 2003
  • Drynariae Rhizorna (DR), an herbal medicine known for its effect to purify blood quality and improve circulation, frequently appears as the main ingredient in prescriptions for bone injuries. Currently, how pharmacologically it contributes to the reformation of bone is unclear. In the present study, the effect of the aqueous extract of DR on bone cells was investigated in vitro for the first time. The human osteoprecursor cells (OPC-I) were incubated in the medium with different concentrations of the aqueous extract of DR and the cell proliferation was studied. When the concentration of DR aqueous extract was $<120{\;}\mu\textrm{g}/ml$, the proliferation of OPC-I was enhanced. However, the proliferation of OPC-I was inhibited by DR extract with the concentrations $>250{\;}\mu\textrm{g}/ml$. Under most treatments, the cells presented very pale expression for cyclooxygenase-2 (Cox 2) protein; a slightly intensified band showed at the highest DR concentration, 1.0 mg/ml during the course of culture. From the results, it was concluded that the aqueous extract of DR was found to directly stimulate the proliferation, alkaline phosphatase (ALP) activity, protein secretion and particularly type I collagen synthesis of OPC-I at dose-dependent manner.

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Restoration of pre-damaged RC bridge columns using basalt FRP composites

  • Fahmy, Mohamed F.M.;Wu, Zhishen
    • Earthquakes and Structures
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    • v.14 no.5
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    • pp.379-388
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    • 2018
  • This study aims to identify the effect of both longitudinal reinforcement details and damage level on making a decision of repairing pre-damaged bridge columns using basalt fiber reinforced polymer (BFRP) jackets. Two RC bridge columns with improper details of the longitudinal and/or transverse reinforcement were tested under the effect of a constant axial load and increasing lateral cyclic loading. Test results showed that the lap-splice column exhibited an inferior performance where it showed rapid degradation of strength before achieving the theoretical strength and its deformation capacity was limited; however, quick restoration is possible through a suitable rehabilitation technique. On the other hand, expensive repair or even complete replacement could be the decision for the column with the confinement failure mode. After that, a rehabilitation technique using external BFRP jacket was adopted. Performance-based design details guaranteeing the enhancement in the inelastic performance of both damaged columns were addressed and defined. Test results of the repaired columns confirmed that both reparability and the required repairing time of damage structures are dependent on the reinforcement details at the plastic hinge zone. Furthermore, lap-splice of longitudinal reinforcement could be applied as a key design-tool controlling reparability and restorability of RC structures after massive actions.

Effects of shirodhara in generalized anxiety disorder

  • Rastogi, Sanjeev;Baiswar, Antriksha;Nischal, Anil;Srivastava, Prem Swarup;Nischal, Anuradha
    • CELLMED
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    • v.6 no.4
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    • pp.27.1-27.4
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    • 2016
  • Anxiety is a common clinical presentation. Primary anxiety poses a significant problem in its management. Many among the current treatment options of anxiety are habit forming causing significant withdrawal symptoms. There are dose dependent responses often associated with drug adversities. Day time sedation is an undesired effect of many drugs used for anxiety management limiting its usage. Ayurveda recommends a bio- physical procedure to manage anxiety. Shirodhara, a dripping procedure is utilized as a front line therapy for anxiety in Ayurveda. Seeing the limitations of conventional biomedical management of anxiety requiring an improvement upon the existing protocols of managements, and also seeing the use of shirodhara for anxiety management in ayurvedic clinics, a pragmatic study to evaluate the effect of shirodhara in generalized anxiety disorder was done. This was a pragmatic study consisting of shirodhara with ksheer bala oil as an intervention upon generalized anxiety disorder patients. The study was conducted upon 13 patients and observations were done for six weeks. The responses observed through the changes in Hamilton Anxiety Scale were evaluated using paired t test to observe the pre-post significance.

Cytoprotective effect of rhamnetin on miconazole-induced H9c2 cell damage

  • Lee, Kang Pa;Kim, Jai-Eun;Park, Won-Hwan
    • Nutrition Research and Practice
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    • v.9 no.6
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    • pp.586-591
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    • 2015
  • BACKGROUND/OBJECTIVES: Reactive oxygen species (ROS) formation is closely related to miconazole-induced heart dysfunction. Although rhamnetin has antioxidant effects, it remained unknown whether it can protect against miconazole-induced cardiomyocyte apoptosis. Thus, we investigated the effects of rhamnetin on miconazole-stimulated H9c2 cell apoptosis. MATERIALS/METHODS: Cell morphology was observed by inverted microscope and cell viability was determined using a WelCount$^{TM}$ cell proliferation assay kit. Miconazole-induced ROS production was evaluated by fluorescence-activated cell sorting with 6-carboxy-2',7'-dichlorofluoroscein diacetate ($H_2DCF$-DA) stain. Immunoblot analysis was used to determine apurinic/apyrimidinic endonuclease 1 (APE/Ref-1) and cleaved cysteine-aspartic protease (caspase) 3 expression. NADPH oxidase levels were measured using real-time polymerase chain reaction. RESULTS: Miconazole (3 and $10{\mu}M$) induced abnormal morphological changes and cell death in H9c2 cells. Rhamnetin enhanced the viability of miconazole ($3{\mu}M$)-treated cells in a dose-dependent manner. Rhamnetin (1 and $3{\mu}M$) treatment downregulated cleaved caspase 3 and upregulated APE/Ref-1 expression in miconazole-stimulated cells. Additionally, rhamnetin significantly reduced ROS generation. CONCLUSIONS: Our data suggest that rhamnetin may have cytoprotective effects in miconazole-stimulated H9c2 cardiomyocytes via ROS inhibition. This effect most likely occurs through the upregulation of APE/Ref-1 and attenuation of hydrogen peroxide levels.

(An) experimental study on the development of lightweight concrete using the PCM (PCM 혼입 경량기포콘크리트 패널 개발을 위한 기초적 연구)

  • Lim, Myung Kwan;Enkhbold, Odontuya;Kim, Young Ho;Choi, Dong Uk
    • KIEAE Journal
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    • v.14 no.4
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    • pp.133-138
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    • 2014
  • The present study was carried out to assess the basic material properties and thermal behavior of light-weight foamed concrete panel mixed with PCM (Phase Changing Material). To do so, this study fabricated light-weight foamed concrete (1.0kg/m3) in pre-foaming method and mixed it with PCM micro capsule of 1-dodecanol and melamine to examine its physical and thermal properties. The results confirmed strength reinforcement effect by proper replacement ratio of fly-ash, which is an industrial by-product, and PCM. In addition, it found out that PCM-mixed light-weight foamed concrete had time delay and temperature reduction effect within the range of PCM phase transition according to the rise of outdoor temperature. It was also observed that the insulation performance of PCM-mixed light-weight foamed concrete was more dependent upon thickness than PCM replacement ratio.

Effects of Endocrine Disruptors on Endocrine Function and Reproductive Function in Wildlife and Humans (내분비교란물질이 야생동물 및 인간의 내분비기능과 생식기능에 미치는 영향)

  • 류병호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1180-1186
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    • 1999
  • A wide ranges of chemicals released into the environment have potential to interfere with physiological and development process by disrupting endocrine pathways. Endocrine system embraces a multitude of mechanisms of action, including effect on growth, behavior, reproduction and immune function. These environmental endocrine disruptors are present in environment and pose potential health consequences to human and wildlife. The best known form in endocrine distruptors involves substances which mimic or block the action of natural hormone in the body. Endocrine disruptor have been variously defined as exogenous agents that interfere with the synthesis, secretion, transport, metabolism, binding action or elimination of the natural hormones in the body which are responsible for the maintenance of homeostasis, reproduction developmental and/or behavior. Many compounds polluted into the environment by human activity are capable of disrupting the endocrine system of animals, including fish, wildlife, and humans. Among these chemicals are pesticides, industrial chemicals, and other anthropogenic products. It has been alleged that several adverse effects on human health are linked with exposure to chemicals which are claimed to be endocrine disrupters, that is, increased incidence of testicular, prostate and female breast cancer, time dependent reductions in sperm quality and quantity, increased incidence of cryptorchidism (undescended testicles) and hypospadias(malformation of the penis), altered physical and mental de velopment in children. This observation is currently the only example of chemically mediated endocrine disruption which has resulted in a clear effect at the population level.

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