• Title, Summary, Keyword: Blood characteristics

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Experimental Investigation on Flow Characteristics of Chicken Blood in a Micro Tube Using a Micro-PIV Technique (마이크로 PIV를 이용한 미세튜브 내부 조류 혈액유동에 관한 실험적 연구)

  • Yeo, Chang-Sub;Ji, Ho-Seong;Lee, Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.11
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    • pp.1027-1034
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    • 2006
  • In order to investigate flow characteristics of chicken blood in a micro tube of 100$\mu$m in diameter, in-vitro experiments were carried out using a micro-PIV technique. The micro-PIV system consists of a microscope, 2-head Nd:YAG laser, 12 bit cooled CCD camera and a delay generator. Chicken blood with 40% hematocrit was supplied into a micro tube using a syringe pump. The blood flow shows clearly the cell free layer near the tube wall and its thickness is increased with increasing the flow speed. The hemorheological characteristics of chicken blood, including shear rate and shear stress were estimated from the PIV velocity field data obtained. Since the aggregation index of chicken blood is less than 50% of human blood, non-Newtonian flow characteristics of chicken blood are smaller than those of human blood. As the flow rate increases, the degree of flatness in the velocity profile at the center region is decreased and the parabola-shaped shear stress distribution becomes to have a linear profile. Under the same flow rate, chicken blood shows higher shear stress, compared with human blood.

Hemodynamic Analysis of Blood Flows in the Extraembryonic Blood Vessels of Chicken Embryos (유정란 태아외부혈관 내부 혈액유동에 대한 혈류역학적 연구)

  • Lee, Jung-Yeop;Lee, Sang-Joon
    • 한국전산유체공학회:학술대회논문집
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    • pp.6-9
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    • 2008
  • Analyzing the characteristics of blood flow in the blood vessels is very important to diagnose the circulatory diseases. In order to investigate the hemodynamic characteristics in vivo, the measurements of blood flows inside the extraembryonic arterial and venous blood vessels of chicken embryos were carried out using an in vivo micro-PIV technique. The circulatory diseases are closely related with the formation of abnormal hemodynamic shear stress regions, thereby it is important to get blood velocity and vessel's morphological information according to the vessel configuration and the flow conditions. In this study, the flow images of RBCs in blood vessels were obtained using a high-speed CMOS camera with a spatial resolution of approximately 14.6${\mu}$m${\times}$14.6${\mu}$m in the whole circulation network of blood vessels. The blood flows in the veins and arteries show steady laminar and unsteady pulsatile flow characteristics, respectively. The mean blood flows merged (in veins) and bifurcated (in arteries) smoothly into the main blood vessel and branches, respectively, without any flow separation or secondary flow which accompanying large variation of shear stress. Vorticity was high in the inner regions for both types of vessels, where the radius of curvature varied greatly. The instantaneous flows in the arterial blood vessels showed noticeable pulsatility due to the heart beat, and the main features of the velocity waveforms, including pulsatile shape, retrograde flow, mean velocity, maximum velocity and pulsatile frequency, were significantly dependent on the pulsatile condition which dominates the arterial blood flow. In near future, these in vivo experimental results of blood flow measured in various extraembryonic blood vessels would be very useful to understand the hemodynamic characteristics of human blood flows and various blood flow researches for clinically useful hemodynamic discoveries as well.

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Hemorheology and Cardiovascular Disease

  • Cho, Young-I.;Kensey, Kenneth R.
    • 순환기질환의공학회:학술대회논문집
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    • pp.3-18
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    • 2002
  • Hemorheology plays an important role in atherosclerosis. Hemorheologic properties of blood include whole blood viscosity, plasma viscosity, hemaocrit, RBC deformability and aggregation, and fibrinogen concentration in plasma. Blood flow is determine by three parameters (pressure, lumen diameter, and whole blood viscosity), whole blood viscosity is one of the key physiological variables. However, the significance of whole blood viscosity has not yet not been fully appreciated. Whole blood viscosity has a unique property, non-Newtonian shear-thinning characteristics, which is primarily due to the presence of RBCs. Hence, RBC deformability and aggregation directly affect the magnitude of blood viscosity, and any factors or diseases affecting RBC characteristics influence blood viscosity. Therefore, on can see that whole blood viscosity is the causal mechanism by which traditional risk factors such as hypertension, hyperlipidemia, smoking, exercise, obesity, age, and gender are related to atherogenesis. In this regard, we included whole blood viscosity in the three key determinants of injurious pulsatile flow that results in mechanical injury and protective adaptation in the arterial system. Because whole blood viscosity is a potential predictor of cardiovascular diseases, it should be measured in routine cardiovascular profiles. Incorporating whole blood viscosity measurements into a standard clinical protocol could improve our ability to identify patients at risk for cardiovascular disease and its complications.

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Effect of hematocrit on hemorheological characteristics of blood flow in a microtube (헤마토크릿에 따른 혈액의 유변학적 특성 변화)

  • Ji, Ho-Seong;Lee, Jung-Yeop;Lee, Sang-Joon
    • 한국가시화정보학회:학술대회논문집
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    • pp.111-112
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    • 2006
  • In order to investigate flow characteristics of blood flow in a micro tube ($100{\mu}m$ in diameter) according to hematocrit, in-vitro experiments were carried out using a micro-PIV technique. The micro-PIV system consists of a microscope, a 2 head Nd:YAG laser, a 12 bit cooled CCD camera and a delay generator. Blood was supplied into the micro tube using a syringe pump. Hematocrit of blood was controlled to be 20%, 30% and 40%. The blood flow has a cell free layer near the tube wall and its thickness was changed with increasing the flow rate and hematocrit. The hemorheological characteristics such as shear rate and viscosity were evaluated using the velocity field data measured. As the flow rate increased, the blunt velocity profile in the tube center was sharpened. The viscosity of blood was rapidly increased with decreasing shear rate, especially in the region of low shear rate, changing RBC rheological properties. The variation of velocity profile and blood viscosity shows typical characteristics of Non-Newtonian fluids. On the basis of inflection points, the cell free layer and two-phase flow consisting of plasma and suspensions including RBCs were clearly discriminated.

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X-ray PIV Measurements of Velocity Field of Blood Flows

  • Lee, Sang-Joon;Kim, Guk-Bae
    • 순환기질환의공학회:학술대회논문집
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    • pp.28-36
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    • 2006
  • The x-ray PIV method was improved for measuring quantitative velocity fields of real blood flows using a coherent synchrotron x-ray source. Without using any contrast media or seeding particles, this method can visualize flow pattern of blood by enhancing the phase-contrast and interference characteristics of blood cells based on a synchrotron x-ray imaging mechanism. The enhanced x-ray images were achieved by optimizing the sample-to-scintillator distance, the sample thickness, and hematocrit. The quantitative velocity fields of blood flows inside opaque tubes were obtained by applying a 2-frame PIV algorithm to the x-ray images of the blood flows. The measured velocity field data show typical features of blood flows such as the yield stress effect. The non-Newtonian flow characteristics of blood flows were analyzed using the x-ray PIV method and the experimental results were compared with hemodynamic models.

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X-ray PIV Measurements of Velocity Field of Blood Flows

  • Lee, Sang-Joon;Kim, Guk-Bae
    • International Journal of Vascular Biomedical Engineering
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    • v.4 no.1
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    • pp.1-8
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    • 2006
  • The x-ray PIV method was improved for measuring quantitative velocity fields of real blood flows using a coherent synchrotron x-ray source. Without using any contrast media or seeding particles, this method can visualize flow pattern of blood by enhancing the phase-contrast and interference characteristics of blood cells based on a synchrotron x-ray imaging mechanism. The enhanced x-ray images were achieved by optimizing the sample-to-scintillator distance, the sample thickness, and hematocrit. The quantitative velocity fields of blood flows inside opaque tubes were obtained by applying a 2-frame PIV algorithm to the x-ray images of the blood flows. The measured velocity field data show typical features of blood flows such as the yield stress effect. The non-Newtonian flow characteristics of blood flows were analyzed using the x-ray PIV method and the experimental results were compared with hemodynamic models.

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Comparative Study on Compositions and Functional Properties of Porcine, Chicken and Duck Blood

  • Sorapukdee, Supaluk;Narunatsopanon, Supawadee
    • Food Science of Animal Resources
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    • v.37 no.2
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    • pp.228-241
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    • 2017
  • Hematological, chemical and functional characteristics of porcine, chicken and duck blood were evaluated. A porcine blood sample showed the most abundant red blood cell, hemoglobin concentration, packed cell volume and plasma protein content as well as its freeze-dried blood possessed the highest contents of protein, fat, Cu and Cr with the highest percentage of heme iron (p<0.05). Unlike porcine blood, chicken blood showed a well balance in some essential amino acids, specifically for a higher isoleucine content (p<0.05). Furthermore, it possessed the highest contents of carbohydrate, Zn and non-heme iron (p<0.05). The most rapid response to form a strong gel, especially at $70^{\circ}C$ and $80^{\circ}C$, was found in chicken blood, followed by duck and porcine blood, respectively. The result of emulsion activity index (EAI) and emulsion stability index (ESI) at the low protein concentration indicated that chicken blood had the most superior emulsion properties (p<0.05). Regarding duck blood, it exhibited the highest content of Mg and Mn (p<0.05). Moreover, duck blood had similar foaming properties to porcine blood in which they showed higher values than chicken blood (p<0.05). Specific characteristics of blood were therefore diminished by animal species in which this information could be used as food supplementation or product development based on their potential applications.

The Study for Correlation Characteristics on Radial Artery and Floating/sinking Pulse with BMI (BMI에 따른 요골동맥의 혈관특성과 부/침맥과의 상관관계 연구)

  • Lee, Yu-Jung;Lee, Jeon;Lee, Hae-Jung;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • v.14 no.3
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    • pp.121-126
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    • 2008
  • Pulse diagnosis refers to the process of diagnosing a patient by feeling an artery on the wrist based on the shape that the pulse take s while the hold-down pressure increase. The styloid process artery on the wrist is usually felt, and the pulse is taken on Chon, Gwan and Cheok using three fingers. This study is to examine the structural difference in the location of pulse diagnosis by measuring and analyzing blood diameter, blood depth, and blood flow velocity of the location of pulse diagnosis by using ultrasonic wave (VOLUSION730 PRO, GE Medical, U.S.A). This study also attempted to grasp whether the characteristics of blood vessels differ depending on Body Mass Index (BMI) and analyzed their correlation with Oriental medical pulse diagnosis. The male subjects without cardiovascular diseases were divided into the normal BMI group, the underweight group and the overweight group and 10 people of each group were measured, Blood depth, blood diameter and blood flow velocity at the location of pulse diagnosis (Chon, Gwan, Cheok) of the wrists of left and right hands were measured and the pulse wave was measured by using pulse diagnosis instrument (3-D Mac, DaeyoMedi, Korea).The results of this study showed that the characteristics of blood vessels differ depending on the degrees of obesity, and the characteristics of floating pulse and sinking pulse of Oriental medical pulses were related to the degrees of obesity. This shows that the characteristics of the blood vessels of subjects and BMI information are the major indicators for diagnosis and are the matters that must always be considered when developing the algorithm of pulse diagnosis.

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NUMERICAL STUDY ON BLOOD FLOW CHARACTERISTICS IN A ARTERIOVENOUS GRAFT WITH DELIVERED DOSE DURING HEMODIALYSIS (인조혈관 동정맥루의 혈액 투석량에 따른 인조혈관 내부 유동 특성에 관한 수치해석 연구)

  • Kim, J.Y.;Ro, K.C.;Ryou, H.S.
    • Journal of computational fluids engineering
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    • v.16 no.4
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    • pp.84-91
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    • 2011
  • Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics through arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

Numerical Study on Blood Flow Characteristics in a Arteriovenous Graft with Delivered dose During Hemodialysis (혈액 투석 시 주사침에서의 투석량에 따른 인조혈관 내부 유동 특성에 관한 수치해석 연구)

  • Kim, J.Y.;Ro, K.C.;Ryou, H.S.
    • 한국전산유체공학회:학술대회논문집
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    • pp.469-476
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    • 2011
  • Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics though arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

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