• Title/Summary/Keyword: wall interaction

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Origin of Proteinuria as Observed from Qualitative and Quantitative Analysis of Serum and Urinary Proteins

  • Takahashi, Shori
    • Childhood Kidney Diseases
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    • v.19 no.2
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    • pp.65-70
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    • 2015
  • It is well known that proteins present in the primary urine are reabsorbed in the renal proximal tubules, and that this reabsorption is mediated via the megalin-cubilin complex and the neonatal $Fc{\gamma}$ receptor. However, the reabsorption is also thought to be influenced by an electrostatic interaction between protein molecules and the microvilli of the renal proximal tubules. By analyzing the charge diversity of urinary IgG, we showed that this reabsorption process occurs in a cationic charge-preferential manner. The charge-selective molecular sieving function of the glomerular capillary walls has long been a target of research since Brenner et al. demonstrated the existence of this function by a differential clearance study by using the anionic dextran sulfate polymer. However, conclusive evidence was not obtained when the study was performed using differential clearance of serum proteins. We noted that immunoglobulin (Ig) A and IgG have similar molecular sizes but distinct molecular isoelectric points. Therefore, we studied the differential clearance of these serum proteins (clearance IgA/clearance IgG) in podocyte diseases and glomerulonephritis. In addition, we studied this differential clearance in patients with Dent disease rather than in normal subjects because the glomerular sieving function is considered to be normal in subjects with Dent disease. Our results clearly showed that the charge-selective barrier is operational in Dent disease, impaired in podocyte disease, and lacking in glomerulonephritis.

Ascophyllum and Its Symbionts. VII. Three-way Interactions Among Ascophyllum nodosum (Phaeophyceae), Mycophycias ascophylli (Ascomycetes) and Vertebrata lanosa (Rhodophyta)

  • Garbary, David J.;Deckert, Ron J.;Hubbard, Charlene B.
    • ALGAE
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    • v.20 no.4
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    • pp.353-361
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    • 2005
  • Ascophyllum nodosum (L.) Le Jolis has a systemic infection with the ascomycete Mycophycias ascophylli (Cotton) Kohlmeyer and Volkmann-Kohlmeyer with which it establishese a mutualistic symbiosis. In addition, A. nodosum is the host for the obligate red algal epiphyte, Vertebrata lanosa (L.) Christensen. Using light and electron microscopy we describe morphological and cytochemical changes occurring as a consequence of rhizoid penetration of V. lanosa into cortical host tissue. Rhizoids induce localized cell necrosis based on physical damage during rhizoid penetration. Host cells adjacent to the rhizoid selectively undergo a hypersensitive reaction in which they become darkly pigmented and become foci for hyphal development. Light and electron microscopy show that M. ascophylli forms dense hyphal aggregations on the surface of the V. lanosa rhizoid and extensive endophytic hyphal growths in the rhizoid wall. This is the first morphological evidence of an interaction between M. ascophylli and V. lanosa. We speculate that M. ascophylli may be interacting with V. lanosa to limit tissue damage to their shared host. In addition, the fungus provides a potential pathway for the transfer of materials (e.g., nutrients and photosynthate) between the two phototrophs.

Effects of an Ultrasonic Standing-wave Field on the Behavior of Methane/Air Premixed Flame (정상초음파장이 메탄/공기 예혼합화염의 거동에 미치는 영향)

  • Seo, Hang-Seok;Lee, Sang-Shin;Kim, Jeong-Soo;Lee, Do-Hyung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.303-306
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    • 2011
  • An experimental study has been conducted to investigate the effects of an ultrasonic standing-wave field to the behavior of methane/air premixed flame. Visualization technique utilizing the schlieren method was employed for the observation of premixed flame behavior. The shape of flame front and local flame velocity were measured according to the variation of reactants pressure and chamber opening/closing condition. The flame front was distorted and severely deformed to a lotus-type flame by the interaction of ultrasonic standing-wave and the reflection wave coming from an end wall of reactor.

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An Analysis of the Farm Silo Supported by Ground (지반과 구조물 사이의 상호작용을 고려한 농업용 사이로의 해석에 관한 연구(IV) -제 4 보 관행설계법과의 비교)

  • 조진구;조현영
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.30 no.2
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    • pp.44-54
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    • 1988
  • This study was carried out to investigate the applicability of the conventional design method for ground supported circular cylindrical shell structures. For this purpose, the ensiled farm silo was adopted as a model structures. Herein, the conventional design method was based on the assumption that such structures are clamped at the bottom edges or the ground pressure is independent of the deflection at the surface. In the present paper, the applicability of above assumption was checked out by comparison with an exact method considering soil-structure interaction. Some results of numerical calculation show us ; When the ground is very hard, for example Winkler's constant k is larger than 100 kg / cm$^2$ / cm, or the bottom plate of structures has a infinitely stiffness, for example the bottom plate thickness is larger than 100 cm, the sectional forces, obtained from the conventional method at any wall of structures resting on an elastic foundation, can used for design purpose. Therefore, if the above condition is satisfied then the conventional assumptions can be justified for the design purpose. In this case, the assumption that such structures are fixed at the lower edges was more realistic than the assumption that the reaction pressure acting on structures is uniformly disributed since the accuracy of results of the analysis by the former assumption was higher than that obtained from the latter assumption. But the sectional forces in the bottom plate resting on ground directly could not be evaluate correctly by the conventional method.

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A New Curve Modeling Tool with the Acoustic Reflection for the Virtual Spatial Conceptual Sketch (가상 공간 개념 스케치를 위한 음향 반향을 포함하는 새로운 곡선 모델링 도구)

  • Choi, Sang-Min;Kim, Hark-Su;Chai, Young-Ho
    • Journal of Korea Multimedia Society
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    • v.12 no.2
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    • pp.281-289
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    • 2009
  • In this paper, a new interaction technique with the virtual single or dual acoustic reflection tablet is proposed to support the perception of depth cue and implement the effective spatial input systems of reducing the depth errors in general spatial sketching tasks. And several experiments show that the virtual wall with acoustic reflections can be thought of as a meaningful feedback for the plausible virtual conceptual design. By using the proposed idea, the degree of agreement to the target model is increased by 35% due to the single acoustic reflection tablet in the constant depth plane. In the slanted plane, the degree of agreement is increased by 8% due to the dual acoustic reflection compared to the single acoustic reflection and the degree of agreement is increased by 15% on the curved vase.

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The Mediating Role of Organizational Citizenship Behavior between Organizational Justice and Organizational Effectiveness in Nursing Organizations (간호조직에서 조직공정성과 조직유효성 관계에서 조직시민행동의 매개역할)

  • Park, Wall-Yun;Yoon, Sook-Hee
    • Journal of Korean Academy of Nursing
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    • v.39 no.2
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    • pp.229-236
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    • 2009
  • Purpose: This study was a secondary analysis to verify the mediating role of organizational citizenship behavior (OCB) between organizational justice (OJ) and organizational effectiveness (OE) in nursing organizations. Methods: The RN-BSNs and their colleagues in Seoul and Busan were subjects. The data was collected for 20 days between September 13 and October 2, 2004. Two hundred eighty three data sets were used for the final analysis. The fitness of models were tested using AMOS 5. Results: The fitness of hypothetical model was moderate. Procedural Justice (PJ), Interaction Justice (IJ) and Distributive Justice (DJ) had direct effects on Job Satisfaction (JS), Organizational Commitment (OC) and Turnover Intention (TI) in OE, and indirect effects on JS, OC and TI mediated by OCB. The modified model improved with ideal fitness showed the causal relations among OE. In modified model, PJ, IJ and DJ had direct positive effects on OCB and JS and OC in OE, and indirect effects on JS and OC mediated by OCB. JS and OC in OE had a direct negative effect on TI. Conclusion: OCB mediated the relationship between OJ and OE, so the nursing managers should enhance OCB of the nurses in order to improve OE.

Measured Effect of Shock Wave on the Stability Limits of Supersonic Hydrogen-Air Flames (충격파가 초음속 수소-공기 화염의 안정한계에 미치는 영향)

  • Hwanil Huh
    • Journal of the Korean Society of Propulsion Engineers
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    • v.3 no.1
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    • pp.86-94
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    • 1999
  • Measured shock wave effects were investigated by changing shock strength and position with particular emphasis on the stability limits of hydrogen-air jet flames. For this purpose, a supersonic nonpremixed, jet-like flame was stabilized along the axis of a Mach 2.5 wind tunnel, and wedges were mounted on the sidewall in order to interact oblique shock waves with the flame. This experiment was the first reacting flow experiment interacting with shock waves. Schilieren visualization pictures, wall static pressures, and flame stability limits were measured and compared to corresponding flames without shock-flame interaction. Substantial improvements in the flame stability limits were achieved by properly interacting the shock waves with the flameholding recirculation zone. The reason for the significant improvement in flame stability limits is believed to be the adverse pressure gradient caused by the shock, which can elongate the recirculation zone.

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An Experimental Study of Shock Wave Effects on the Model Scramjet Combustor (모델 스크램제트 연소기에서 충격파 영향에 대한 실험적 연구)

  • 허환일
    • Journal of the Korean Society of Propulsion Engineers
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    • v.3 no.1
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    • pp.65-71
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    • 1999
  • An experimental study was carried out in order to investigate the effect of shock waves on the supersonic hydrogen-air jet flames stabilized in the Mach 2.5 model scramjet combustor. This experiment was the first reacting flow experiment interacting with shock waves. Two identical $10^{\cire}$ wedges were mounted on the diverging sidewalls of the combustor in order to produce oblique shock waves that interacted with the flame. Schlieren visualization pictures, wall static pressures, and combustion efficiency at two different air stagnation temperatures were measured and compared to corresponding flames without shock wave-flame interaction. It was observed that shock waves significantly altered the shape of supersonic jet flames, but had different effects on combustion efficiency depending on air temperatures. At the higher air stagnation temperature and higher fuel flow rates, combustion of efficiency showed a better result.

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A Study of Film Cooling of a Cylindrical Leading Edge with Shaped Injection Holes (냉각홀 형상 변화에 따른 원형봉 선단의 막냉각 특성 연구)

  • Kim, S.M.;Kim, Youn J.;Cho, H.H.
    • The KSFM Journal of Fluid Machinery
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    • v.6 no.3 s.20
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    • pp.21-27
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    • 2003
  • Dispersion of coolant jets in a film cooling flow field is the result of a highly complex interaction between the film cooling jets and the mainstream. In order to investigate the effect of blowing ratios on the film cooling of a turbine blade, cylindrical body model is used. Mainstream Reynolds number based on the cylinder diameter is $7.1{\times}10^4$. The effects of coolant flow rates are studied for blowing ratios of 0.7, 1.0, 1.3 and 1.7, respectively. The temperature distribution of the cylindrical model surface is visualized with infrared thermography (IRT). Results show that the film cooling performance could be significantly improved by the shaped injection holes. For higher blowing ratio, the spanwise-diffused injection holes are better due to the lower momentum flux away from the wall plane at the hole exit.

Effects of Incidence on Aerodynamic Losses in the Tip-Leakage Flow Region of a High-Turning Turbine Rotor Blade (입사각이 터빈 동익 팁누설유동 영역에서의 압력손실에 미치는 영향)

  • Chae, Byoung-Joo;Lee, Sang-Woo
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.2
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    • pp.41-47
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    • 2010
  • The effect of incidence angle on the three-dimensional flow and aerodynamic loss in the tip leakage flow region downstream of a turbine rotor cascade has been investigated for two tip gap-to-chord ratios of h/c=0.0% (no tip gap) and 2.0%. The incidence angle is changed to be $i=-10^{\circ}$, $0^{\circ}$, and $5^{\circ}$. The results show that for $i=5^{\circ}$, secondary flows including the passage vortex are intensified noticeably, and there is a strong interaction between the passage and tip leakage vortices. For $i=-10^{\circ}$, however, the passage vortex is weakened significantly, so that there exists only a strong leakage-jet-like secondary flows near the casing wall. For h/c=0.0% and 2.0%, aerodynamic loss tends to increase with increasing i from $-10^{\circ}$ to $5^{\circ}$. A small increment of i in its positive incidence range results in a remarkable aerodynamic loss increase, while increasing i in the negative incidence range leads to a small change in the aerodynamic loss generation.