• Title/Summary/Keyword: RoB

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Evaluation of water permeability of forward osmosis membranes using osmotically driven membrane test (랩스케일 정삼투실험을 통한 정삼투막의 수투과도 평가)

  • Lee, Junseo;Kim, Suhan
    • Journal of Korean Society of Water and Wastewater
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    • v.30 no.4
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    • pp.417-425
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    • 2016
  • Desalination is a key technology to overcome water shortage problem in a near future. High energy consumption is an Achilles' heel in desalination technology. Osmotically driven membrane processes like forward osmosis(FO) was introduced to address this energy issue. Characterizing membrane properties such as water permeability(A), salt permeability(B), and the resistance to salt diffusion within the support layer($K_{ICP}$) are very important to predict the performance of scaled-up FO processes. Currently, most of researches reported that the water permeability of FO membrane was measured by reverse osmosis(RO) type test. Permeating direction of RO and FO are different and RO test needs hydraulic pressure so that several problems can be occurred(i.e. membrane deformation, compaction and effect of concentration polarization). This study focuses on measuring water permeability of FO membrane by FO type test results in various experimental conditions. A statistical approach was developed to evaluate the three FO membrane properties(A, B, and $K_{ICP}$) and it predicted test result by the internal and external concentration polarization model.

Recent Research Trends in Moxibustion Treatment in Korea

  • Lee, Ju-Hyeon;Hwang, Doo-ree;Hong, Seung-Hyo
    • Journal of Acupuncture Research
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    • v.37 no.1
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    • pp.1-12
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    • 2020
  • A total of 1,235 studies were retrieved on June 23, 2019, from 3 databases. Selected 59 studies were evaluated by year of publication, study type, subject condition/disease, acupoint, standards for reporting interventions in clinical trials of moxibustion (STRICTOM), Cochrane risk of bias (RoB), and risk of bias assessment tool for non-randomized study (RoBANS). Most studies were conducted in 2011, after which the number of studies decreased. The most common study type was 25 case reports (CR), 16 uncontrolled clinical trials (UCT), 11 randomized controlled trials (RCT), and 7 controlled clinical trials (CCT). Moxibustion treatment was mainly used for musculoskeletal and circulatory diseases/conditions. A total of 83 acupoints were used, A-shi points being the most used. As for STRICTOM, an average of 7.4 items were satisfactory for UCT and CR without a control group, and an average of 9.4 items were satisfactory for RCT and CCT. RCT was assessed using the RoB, and many items were rated as uncertain. In this study, the need for RCT of moxibustion treatment in Korea was identified. The detailed description of study methods and results will provide evidence for the efficacy of moxibustion treatment in preventive and therapeutic aspects of Korean traditional medicine.

Central Involvement of Benzodiazepine Receptor on the Muscimol-induced Inhibition of Micturition Reflex in Rats (흰쥐의 뮤시몰투여에 의한 배뇨반사억제효과에 대한 벤조디아제핀수용체의 영향)

  • Huh, In-Hoi;Oh, Ho-Jung
    • YAKHAK HOEJI
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    • v.36 no.5
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    • pp.496-505
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    • 1992
  • The correlation between GABA receptors($GABA_A$ and $GABA_B$ receptor) and benzodiazepine receptor on the saline infusion-induced micturition reflex contraction was studied in the female rat. To investigate the effect of ${\gamma}-aminobutyric$ acid(GABA) on the micturition reflex, exogenous GABA(10 mg/kg) and GABA transaminase inhibitor(aminooxyacetic acid; AOAA $1\;{\mu}g$) were administered intravenously(i.v.) and intracerebroventriculary(i.c.v.), respectively. In result, both GABA and AOAA inhibited the saline induced micturition reflex contraction. This AOAA induced inhibition of micturition reflex was blocked by both bicuculine. $GABA_A$ receptor antagonist, and Ro 15-1788, benzodiazepine receptor antagonist. Muscimol, $GABA_A$ receptor antagonist($0.1\;{\mu}g$ i.c.v., $3\;{\mu}g$ intrathecal; i.t., 1 mg/kg i.v.) and baclofen, $GABA_A$ receptor agonist($1\;{\mu}g$ i.c.v., $3\;{\mu}g$ i.t., 1 mg/kg i.v.) also inhibited the bladder contraction. Pretreatment of bicuculline($1\;{\mu}g$ i.c.v.), but not of 5-aminovaleric acid(AVA, $1\;{\mu}g$ i.c.v.), $GABA_B$ receptor antagonist blocked the central inhibition of muscimol. These inhibitory effects were reversed by Ro15-1788 but were potentiated by flurazepam, benzodiazepine receptor antagonist. On the other hand, the inhibitory effects of baclofen were not affected by Ro 15-1788. Diazepam and flurazepam also inhibited the micturition reflex contraction when they were administered $3\;{\mu}g$ i.c.v., $10\;{\mu}g$ i.t., $10\;{\mu}M$, $30\;{\mu}M$ transurethrally, respectively. In conclusion, these results suggest that the micturition reflex is mediated by $GABA_A$, $GABA_B$ receptor and benzodiazepine receptor. The bezodiazepines increase the receptor binding of GABA to the $GABA_A$ receptor, so that the benzodiiazepines show the synergistic effect on the inhibition of the micturition reflex contraction, but not to the $GABA_B$ receptor.

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Effect of trans-10, cis-12 Conjugated Linoleic Acid on Calcium-Dependent Reactive Oxygen Species and Nitric Oxide Production and Nuclear Factor-${\kappa}B$ Activation in Lipopolysaccharide-Stimulated RAW 264.7 Cells (LPS 자극 RAW 264.7 세포에 있어서 칼슘의존성 ROS와 NO 생산 및 NF-${\kappa}B$ 활성에 대한 CLA의 억제효과)

  • Choi, Tae-Won;Kang, Byeong-Teck;Kang, Ji-Houn;Yang, Mhan-Pyo
    • Journal of Veterinary Clinics
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    • v.32 no.2
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    • pp.135-140
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    • 2015
  • Trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) has been shown to participate in the regulation of anti-inflammatory effects. The objectives of this study were to examine the effects of t10c12-CLA on reactive oxygen species (ROS) and nitric oxide (NO) production and nuclear factor-kappaB (NF-${\kappa}B$) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and to determine whether these effects were associated with change of intracellular calcium ion ($Ca^{2+}$). ROS production was increased in LPS-stimulated RAW 264.7 cells, and this effect was suppressed by 1,2-bis-(o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM), a calcium chelator. t10c12-CLA suppressed ROS production in LPS-stimulated RAW 264.7 cells, which was further more decreased by treatment with BAPTA/AM. These indicated that t10c12-CLA decreases $Ca^{2+}$-dependent ROS production in LPS-stimulated RAW 264.7 cells. Similarly, NF-${\kappa}B$ p65 DNA binding activity and NO production were decreased by treatment with either t10c12-CLA, BAPTA/AM, or t10c12-CLA and BAPTA/AM combination. However, there were no differences between t10c12-CLA and BAPTA/AM treatment in NO production of LPS-stimulated RAW 264.7 cells. These data indicate that t10c12-CLA inhibits the increases in ROS and NO production and the NF-${\kappa}B$ activation in LPS-stimulated condition. These results suggested that CLA exerts potent anti-inflammatory effects by suppression of LPS-induced ROS and NO production, and NF-${\kappa}B$ activationn via $Ca^{2+}$-dependent pathway.

Study on of Process Parameters for Adsorption of Reactive Orange 16 Dye by Activated Carbon (활성탄에 의한 Reactive Orange 16 염료 흡착에 대한 공정 파라미터 연구)

  • Lee, Jong Jib
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.7
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    • pp.667-674
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    • 2020
  • The adsorption of reactive orange 16 (RO 16) dye by activated carbon was investigated using the amount of adsorbent, pH, initial concentration, contact time and temperature as adsorption variables. The investigated process parameters were separation coefficient, rate constant, rate controlling step, activation energy, enthalpy, entropy, and free energy. The adsorption of RO 16 was the highest at pH 3 due to the electrostatic attraction between the cations (H+) on the surface of the activated carbon and the sulfonate ions and hydroxy ions possessed by RO 16. Isotherm data were fitted into Langmuir, Freundlich and Temkin isotherm models by applying the evaluated separation factor of Langmuir (RL=0.459~0.491) and Freundlich (1/n=0.398~0.441). Therefore, the adsorption operation of RO 16 by activated carbon was confirmed as an appropriate removal method. Temkin's adsorption energy indicated that this adsorption process was physical adsorption. The adsorption kinetics studies showed that the adsorption of RO 16 follows the pseudo-second-order kinetic model and that the rate controlling step in the adsorption process was the intraparticle diffusion step. The positive enthalpy change indicated an endothermic process. The negative Gibbs free energy change decreased in the order of -3.16 <-11.60 <-14.01 kJ/mol as the temperature increased. Therefore, it was shown that the spontaneity of the adsorption process of RO 16 increases with increasing temperature.

Anti-inflammatory and antioxidant effects of Barringtonia augusta Kurz extract (Barringtonia augusta Kurz 추출물의 항염증 및 항산화 효능 평가)

  • Ryu, Soo Ho;Kim, Min Jeong;Bach, Tran The;Jung, Sung Keun
    • Korean Journal of Food Science and Technology
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    • v.53 no.2
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    • pp.154-159
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    • 2021
  • Barringtonia augusta Kurz is a species of the genus Barringtonia. Although several studies have analyzed the biological activity of B. racemosa Roxb and B. acutangula, the anti-inflammatory and antioxidant effects of B. augusta extract (BKE) remain unclear. Therefore, in this study, we investigated the anti-inflammatory and antioxidant effects of BKE using lipopolysaccharide (LPS) and RAW 264.7. BKE suppressed LPS-induced nitric oxide (NO) and inducible NO synthase expression without affecting RAW 264.7 cell viability. Additionally, BKE showed 2,2-Diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging capacities and inhibited LPS-induced reactive oxygen species production in RAW 264.7 cells. BKE also suppressed LPS-induced phosphorylation of IκB kinase and nuclear factor kappa-B (NF-κB) and p65 translocation from the cytosol to the nucleus in RAW 264.7 cells. These results suggest that BKE is a possible novel material that exerts beneficial antioxidant and anti-inflammatory effects through the inhibition of NF-κB signaling pathways.

Predistortion for Frequency-Dependent Nonlinearity of a Laser in RoF Systems

  • Najarro, Andres C.;Kim, Sung-Man
    • Journal of information and communication convergence engineering
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    • v.14 no.3
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    • pp.147-152
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    • 2016
  • In radio-over-fiber (RoF) systems, nonlinear compensation is essential to improve performance. Among the several existing nonlinear compensation techniques, we investigate a predistortion technique for a directly modulated laser in an RoF system. First, we obtain the input-to-output response of a directly modulated laser at 160, 820, and 1,540 MHz. The results show that the laser response is dependent on the frequency band. Second, we design an optimal predistortion circuit to compensate for the nonlinear responses of three frequency bands. We design the predistortion circuit with two options: each predistortion circuit for each frequency band and one single predistortion circuit for all the three frequency bands. Finally, we present the simulation results of the predistortion system obtained using a commercial simulator. These results show that the third intermodulation distortion (IMD3) is improved by 0.6-9 dB for the three frequency bands with only a single predistortion circuit.