• Title/Summary/Keyword: Circulating

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Expanded IL-22+ Group 3 Innate Lymphoid Cells and Role of Oxidized LDL-C in the Pathogenesis of Axial Spondyloarthritis with Dyslipidaemia

  • Hong Ki Min;Jeonghyeon Moon;Seon-Yeong Lee;A Ram Lee;Chae Rim Lee;Jennifer Lee;Seung-Ki Kwok;Mi-La Cho;Sung-Hwan Park
    • IMMUNE NETWORK
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    • v.21 no.6
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    • pp.43.1-43.14
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    • 2021
  • Group 3 innate lymphoid cells (ILC3), which express IL-22 and IL-17A, has been introduced as one of pathologic cells in axial spondyloarthritis (axSpA). Dyslipidaemia should be managed in axSpA patients to reduce cardiovascular disease, and dyslipidaemia promotes inflammation. This study aimed to reveal the role of circulating ILC3 in axSpA and the impact of dyslipidaemia on axSpA pathogenesis. AxSpA patients with or without dyslipidaemia and healthy control were recruited. Peripheral blood samples were collected, and flow cytometry analysis of circulating ILC3 and CD4+ T cells was performed. The correlation between Ankylosing Spondylitis Disease Activity Score (ASDAS)-C-reactive protein (CRP) and circulating immune cells was evaluated. The effect of oxidized low-density lipoprotein cholesterol (oxLDL-C) on immune cell differentiation was confirmed. AxSpA human monocytes were cultured with with oxLDL-C, IL-22, or oxLDL-C plus IL-22 to evaluate osteoclastogenesis using tartrate-resistant acid phosphatase (TRAP) staining and real-time quantitative PCR of osteoclast-related gene expression. Total of 34 axSpA patients (13 with dyslipidaemia and 21 without) were included in the analysis. Circulating IL-22+ ILC3 and Th17 were significantly elevated in axSpA patients with dyslipidaemia (p=0.001 and p=0.034, respectively), and circulating IL-22+ ILC3 significantly correlated with ASDAS-CRP (Rho=0.4198 and p=0.0367). Stimulation with oxLDL-C significantly increased IL-22+ ILC3, NKp44- ILC3, and Th17 cells, and these were reversed by CD36 blocking agent. IL-22 and oxLDL-C increased TRAP+ cells and osteoclast-related gene expression. This study suggested potential role of circulating IL-22+ ILC3 as biomarker in axSpA. Furthermore, dyslipidaemia augmented IL-22+ ILC3 differentiation, and oxLDL-C and IL-22 markedly increased osteoclastogenesis of axSpA.

A Numerical Study of the Characteristics of Heat Transfer in External Heat Exchanger of CFB Boiler (순환유동층보일러 외부열교환기의 열전달 특성에 관한 수치해석적 연구)

  • Hwang, Moonkyeong;Kim, Jungrae
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.15-16
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    • 2014
  • With the increasing trend in CFB(Circulating Fluidized Bed) boiler scale, the EHE(External Heat Exchanger) must be adopted to the large-scale boilers to recover insufficient heat transfer surface. In this study, the numerical analysis model for EHE in commercial 300MWe CFB boiler was developed with the inclusion of mechanistic model, which enables the heat transfer prediction. Finally, the calculated absorbed heat and derived heat transfer coefficient are evaluated through the verification with experimental data.

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Input Power Factor Control of Dual Converter Rectifier (Dual Converter 정류회로의 입력 역율 제어)

  • Lee, Gyu-Jong;Seong, Se-Jin
    • Proceedings of the KIEE Conference
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    • 1988.11a
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    • pp.385-387
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    • 1988
  • Dual converter is being used as a four-quadrant source for the controlled rectifier. But the rectifier itself and circulating current between P and N-converter contribute to generate reactive power. The methodology of input power factor control of dual converter by means of circulating current control is presented in this paper.

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A Study on Dioxin Reduction Characteristics of Rapid Cooling Type Circulating Fluidized Bed Heat Exchanger (급속냉각형 순환유동층 열교환기의 다이옥신 저감성능 연구)

  • Park, Sang-il
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.1231-1236
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    • 2008
  • The flow and heat transfer performance were measured at high temperatures in CFB heat exchanger with multiple risers and downcomers. The theoretical model for predicting heat exchanger performance was developed in this study. The model predictions were compared with the measured heat transfer rates to show relatively good agreement. The maximum gas cooling rate was $20,300^{\circ}C/sec$, and the dioxin reduction rate was 68%.

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Effects of Squalene on the Immune Responses in Mice(I): Humoral Immune Responses of Squalene

  • Ahn, Young-Keun;Kim, Joung-Hoon
    • Archives of Pharmacal Research
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    • v.14 no.4
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    • pp.370-378
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    • 1991
  • Effects of squalene on humoral immune system in mice were investigated. Squalene exhibited significant increases in the circulating leukocyte counts and relative spleen and thymus weights of the mice. However, the relative liver weight was slightly decreased. Hemagglutination titers (HA) were signficantly enhanced by squalene while Arthus reaction was not affected. Splenic plaque forming cells (PFC) were also greatly increased by squalene, especially at doses of 50 and 100 mg/kg of it.

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A Study on Biased Flow Region Using PIV Technique (PIV기법을 이용한 편향흐름 발생영역 규명)

  • Na, Jeong-Heon;Kwon, Sun-Hong
    • Journal of Ocean Engineering and Technology
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    • v.13 no.1 s.31
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    • pp.105-112
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    • 1999
  • This research is an experimental investigation of the region of the Biased Flow. This experiment was carried out in a circulating water channel, and the results are analyzed by using the PIV technique. The results are presented in velocity vector field, velocity contour and vorticity contour. The results were compared with those of Zdravkovich which were carried out in a wind tunnel. These results will be very useful to verify numerical codes.

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A Study on Prediction Model of Flow and Heat Transfer in the Circulating Fluidized Bed Heat Exchanger with Multiple Vertical Tubes (다관형 순환유동층 열교환기의 유동 및 전열성능 예측모델 연구)

  • Park, Sang-Il
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.1199-1204
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    • 2006
  • The pressure drop and heat transfer coefficient were measured at room temperature in CFB heat exchanger with multiple vertical tubes. Also the circulation rate of solid particles was measured. The theoretical model for predicting heat transfer coefficient using the solid flowrate was developed in this study. The model predictions were compared with the measured heat transfer coefficient to show relatively good agreement.

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Performance Evaluation of Ocean Small Hydropower Plant by Analyzing Water Level and Flow Rate of Circulating Water (방류수의 수위 및 유량 분석을 통한 해양 소수력 성능평가)

  • Kang, Keum-Seok;Kim, Ji-Young;Ryu, Moo-Sung
    • New & Renewable Energy
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    • v.5 no.3
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    • pp.32-39
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    • 2009
  • The Samcheonpo ocean small hydropower plant (SHP) has a special feature of using marginal hydraulic head of circulating water system of fossil fuel power plant as a power source and having the characteristics of general hydropower generation and tidal power generation as well. Also, it contributes to reducing green house gases and developing clean energy source by recycling circulating water energy otherwise dissipated into the ocean. The efficiency of small hydropower plant is directly affected by effective head and flow rate of discharged water. Therefore, the efficiency characteristics of ocean hydropower plant are analyzed with the variation of water level and flow rate of discharged water, which is based on the accumulated operation data of the Samcheonpo hydropower plant. After the start of small hydropower plant operation, definite rise of water level was observed. As a result of flow pattern change from free flow to submerged flow, the instability of water surface in overall open channel is increased but it doesn't reach the extent of overflowing channel or having an effect on circulation system. Performance evaluation result shows that the generating power and efficiency of small hydropower exceeds design requirements in all conditions. Analysis results of CWP's water flow rate verify that the amount of flowing water is measured less and the highest efficiency of small hydropower plant is achieved when the effective head has its maximum value. In conclusion, efficiency curve derived from water flow rate considering tidal level shows the best fitting result with design criteria curve and it is verified that overall efficiency of hydropower system is satisfactory.

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Low Non-NMDA Receptor Current Density as Possible Protection Mechanism from Neurotoxicity of Circulating Glutamate on Subfornical Organ Neurons in Rats

  • Chong, Wonee;Kim, Seong Nam;Han, Seong Kyu;Lee, So Yeong;Ryu, Pan Dong
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.2
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    • pp.177-181
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    • 2015
  • The subfornical organ (SFO) is one of circumventricular organs characterized by the lack of a normal blood brain barrier. The SFO neurons are exposed to circulating glutamate ($60{\sim}100{\mu}M$), which may cause excitotoxicity in the central nervous system. However, it remains unclear how SFO neurons are protected from excitotoxicity caused by circulating glutamate. In this study, we compared the glutamate-induced whole cell currents in SFO neurons to those in hippocampal CA1 neurons using the patch clamp technique in brain slice. Glutamate ($100{\mu}M$) induced an inward current in both SFO and hippocampal CA1 neurons. The density of glutamate-induced current in SFO neurons was significantly smaller than that in hippocampal CA1 neurons (0.55 vs. 2.07 pA/pF, p<0.05). To further identify the subtype of the glutamate receptors involved, the whole cell currents induced by selective agonists were then compared. The current densities induced by AMPA (0.45 pA/pF) and kainate (0.83 pA/pF), non-NMDA glutamate receptor agonists in SFO neurons were also smaller than those in hippocampal CA1 neurons (2.44 pA/pF for AMPA, p<0.05; 2.34 pA/pF for kainate, p< 0.05). However, the current density by NMDA in SFO neurons was not significantly different from that of hippocampal CA1 neurons (1.58 vs. 1.47 pA/pF, p>0.05). These results demonstrate that glutamate-mediated action through non-NMDA glutamate receptors in SFO neurons is smaller than that of hippocampal CA1 neurons, suggesting a possible protection mechanism from excitotoxicity by circulating glutamate in SFO neurons.

Development of a Rice Circulating Concurrent-flow Dryer (I) - Performance Test of Pilot Scale Dryer - (순환식 병류형 곡물건조기 개발 (I) -시작기의 성능시험 -)

  • Han J.W.;Keum D.H.;Han J.G.;Kim H.;Hong S.J.
    • Journal of Biosystems Engineering
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    • v.31 no.4 s.117
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    • pp.349-354
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    • 2006
  • This study was performed to evaluate the performances for a concurrent flow rice dryer of pilot scale with devices for circulating rice. The pilot scale dryer with the capacity of 700 kg was developed to obtain design informations for the development of actual scale dryer of holding capacity of 10 tons. Three drying tests were conducted at two temperature levels of $100^{\circ}C\;and\;120^{\circ}C$, and two air flow rates levels of $28.5cmm/m^2\;and\;57.1cmm/m^2$. Drying conditions for Test-1, Test-2 and Test-3 were $100^{\circ}C\;-28.5cmm/m^2,\;120^{\circ}C-28.5cmm/m^2\;and\;120^{\circ}-57.1cmm/m^2}$ respectively. Drying rates were 0.73%(w.b./h) for Test-1, 0.90%(w.b./h) for Test-2 and 1.46%(w.b./h) for Test-3. The crack ratios of brown rice after drying ranged from 2.4% to 8.4%, and increased with the increase of drying rate and airflow rate. The energy consumptions were from 6,225 kJ/kg to 6,993 kJ/kg which was higher than that of conventional cross-flow rice circulating type dryer used in Korea. This results were due to the lower ambient air temperatures of $4.5^{\circ}C\;to\;13.4^{\circ}C$ during drying tests.