• 대한영양사협회학술지
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• 제26권1호
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• pp.14-29
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• 2020

Dietary nitrate supplementation from green leafy vegetables and beetroot is involved in the 'nitrate-nitrite-nitric oxide (NO) pathway' and is reported to have important vascular impacts. This study evaluated the blood parameters and blood flow change subsequent to a raw juice diet program. The 28 subjects who voluntarily participated in the raw juice diet program at Sahmyook University were instructed to drink the juice composed of fruits and vegetables instead of partaking the usual meal, at a scheduled time daily. The study was approved by the research ethics council of the Sahmyook University (SYUIRB 2014-043). Evaluation of the participants after the required duration revealed decreased levels of soft lean mass (P<0.05), skeletal muscle mass (P<0.001), body fat mass (P<0.001), body mass index (P<0.001) and circulating levels of total cholesterol (P<0.001), triglycerides (P<0.05), HDL-cholesterol (P<0.01), LDL-cholesterol (P<0.01), and blood urea nitrogen (P<0.001). Conversely, circulating levels of creatinine (P<0.001), hemoglobin (P<0.001), and hematocrit (P<0.01) were increased after the intervention. The blood flow levels were also increased after the program (P<0.001). Our results indicate that a short-term raw juice diet contributes to the improvement of vascular blood flow and blood lipid parameters, and decreases the lean muscle mass related to dehydration.

• Korea-Australia Rheology Journal
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• 제17권2호
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• pp.47-62
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• 2005

The present study deals with a mathematical model describing the dynamic response of heat and mass transfer in blood flow through bifurcated arteries under stenotic condition. The geometry of the bifurcated arterial segment possessing constrictions in both the parent and the daughter arterial lumen frequently appearing in the diseased arteries causing malfunction of the cardiovascular system, is formulated mathematically with the introduction of the suitable curvatures at the lateral junction and the flow divider. The blood flowing through the artery is treated to be Newtonian. The nonlinear unsteady flow phenomena is governed by the Navier-Stokes equations while those of heat and mass transfer are controlled by the heat conduction and the convection-diffusion equations respectively. All these equations together with the appropriate boundary conditions describing the present biomechanical problem following the radial coordinate transformation are solved numerically by adopting finite difference technique. The respective profiles of the flow field, the temperature and the concentration and their distributions as well are obtained. The influences of the stenosis, the arterial wall motion and the unsteady behaviour of the system in terms of the heat and mass transfer on the blood stream in the entire arterial segment are high­lighted through several plots presented at the end of the paper in order to illustrate the applicability of the present model under study.

• Korea-Australia Rheology Journal
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• 제21권3호
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• pp.161-173
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• 2009

This study analyzes especially drag and lift models recently developed for fluid-solid, fluid-fluid or liquid-liquid two-phase flows to understand their applicability on the computational fluid dynamics, CFD modeling of pulsatile blood flow. Virtual mass effect and the effect of red blood cells, RBCs aggregation on CFD modeling of blood flow are also shortly reviewed to recognize future tendencies in this field. Recent studies on two-phase flows are found as very useful to develop more powerful drag-lift models that reflect the effects of blood cell's shape, deformation, concentration, and aggregation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1487-1491
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• 2008

Detailed knowledge on the motion of blood cells flowing in micro-channels under simple shear flow and the influence of blood flow is essential to provide a better understanding on the blood rheological properties and blood cell aggregation. The microscopic behavior of red blood cell (RBCs) is numerically investigated using a fluid-structure interaction (FSI) method based on the Arbitrary-Lagrangian-Eulerian (ALE) approach and the dynamic mesh method (smoothing and remeshing) in FLUENT (ANSYS Inc., USA). The employed FSI method could be applied to the motions and deformations of a single blood cell and multiple blood cells, and the primary thrombogenesis caused by platelet aggregation. It is expected that, combined with a sophisticated large-scale computational technique, the simulation method will be useful for understanding the overall properties of blood flow from blood cellular level (microscopic) to the resulting rheological properties of blood as a mass (macroscopic).

• Journal of applied mathematics & informatics
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• 제9권2호
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• pp.731-744
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• 2002

The temperature distribution in human skin and subdermal tissue layer is presented using bioheat transfer equation. The body temperature is determined by the balance between heat produced and heat lost by our body. The time-dependent solutions have been found to be affected by the metabolic heat generation rate, blood mass flow, the rate of evaporation of perspiration and also by the atmospheric temperature. The analytic solutions for different layers have been calculated numerically and are also shown graphically.

• Korea-Australia Rheology Journal
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• 제18권2호
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• pp.51-65
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• 2006

Of concern in the present theoretical investigation is the study of blood flow and convection-dominated diffusion processes in a model bifurcated artery under stenotic conditions. The geometry of the bifurcated arterial segment having constrictions in both the parent and its daughter arterial lumen frequently appearing in the diseased arteries causing malfunction of the cardiovascular system, is constructed mathematically with the introduction of suitable curvatures at the lateral junction and the flow divider. The streaming blood contained in the bifurcated artery is treated to be Newtonian. The flow dynamical analysis applies the two-dimensional unsteady incompressible nonlinear Wavier-Stokes equations for Newtonian fluid while the mass transport phenomenon is governed by the convection diffusion equation. The motion of the arterial wall and its effect on local fluid mechanics is, however, not ruled out from the present model. The main objective of this study is to demonstrate the effects of constricted flow characteristics and the wall motion on the wall shear stress, the concentration profile and on the mass transfer. The ultimate numerical solutions of the coupled flow and diffusion processes following a radial coordinate transformation are based on an appropriate finite difference technique which attain appreciable stability in both the flow phenomena and the convection-dominated diffusion processes.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1919-1922
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• 2003

Bypass anastomosis are frequently adopted for surgical treatments. After the bypass grafting, the bypass artery is often occluded due to restenosis and/or anastomotic neointimal fibrous hyperplasia phenomena. Optimal coronary bypass anastomosis should be investigated to improve the patency for the arterial bypass techniques. The objective of this study is to investigate the influence of bypass with sequential bypass effects in the stenosed coronary artery. Numerical analyses are focused on the understanding of the flow patterns for different sequential anastomosis techniques. Blood flow field is treated as two-dimensional incompressible laminar flow. The finite volume method is adopted for discretization of the governing equations. The Carreau model is employed as the constitutive equation for blood. To find the optimal sequential bypass anastomotic configurations, the mass flow rates at the outlet of different models are compared quantitatively.

• 동의생리병리학회지
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• 제20권6호
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• pp.1431-1441
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• 2006

Following conclusions were drawn from the examination of the usage of semen persicae and fols carthami from the view of Hyungsang Medicine. Semen persicae is used to vitalize the blood flow and eliminate the blood stagnation of the whole body in ${\ulcorner}$Donguibogam${\lrcorner}$, and therefor it is used for the blood flow of the heptal meridian and sometimes the intestinal meridian. Flos carthami is applied to vitalize the blood flow, remove obstructions in meridians, eliminate the blood stagnations, and stop the pain in ${\ulcorner}$Donguibogam${\lrcorner}$, therefore used in such symptoms of blood flow of the heptal meridian as amenorrhea, spasm of muscles, and coldness of the genitals. Also is applied in those cases of exhaustion, perspiration, and in digestive remedies which belong to the symptoms of cardiac blood flow. And it is used for dryness of the skin in which case the blood should be developed and malaria for the elimination of the blood stagnation and production of new blood. The combination of semen persicae and flos carthami is applied to eliminate the blood stagnation and stimulate menstrual discharge in uterus, as well as in the cases of lumbago and stomachache due to blood stagnation, blood stasis, mass in the abdomen, and abdominal distention. This combination is also used for the eyes, ears, numbness, and paralysis of hands and feet for the purpose of making the flow of the meridian smooth, and for diabetes, dryness of the skin, malaria, anal itching and pain for the purpose of eliminating the mass and renewing the tissues. The combination is diversly used in the book of ${\ulcorner}$Special lectures on clinical cases${\lrcorner}$ for the aftereffects of traffic accident, constipation, diabetes, dryness of the skin, paralysis of hands and feet, numbness of finger of hand and foot, and especially used frequently with prescription of Yijintang and Samultang combined in the cases of numbness. The prescription is used in Hyungsang medicine when the uterus, the external appearance(axis), hands and feet, heart, and the stomach is not good for the vitalization of the flow of the 12 meridians. It was though difficult to find extinguishing differences between the two herbs in the clinical cases applied in the book of ${\ulcorner}$Special lectures on clinical cases${\lrcorner}$.

• The Korean Journal of Physiology and Pharmacology
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• 제19권3호
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• pp.191-196
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• 2015

Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with low intensity resistance exercise (LIRE) has been used for such special populations to improve their function and exercise capacity. Although BFR+LIRE has been intensively studied for a decade, a comprehensive review detailing the effects of BFR+LIRE on both skeletal muscle and vascular function is not available. Therefore, the purpose of this review is to discuss previous studies documenting the effects of BFR+LIRE on hormonal and transcriptional factors in muscle hypertrophy and vascular function, including changes in hemodynamics, and endothelial function.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1655-1659
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• 2008

Using numerical models, we investigated the efficiency of toxin removal using pulsatile flow in blood purification systems that use semipermeable membranes. The model consisted of a three-compartmental mass transfer model for the inside body and a solute kinetics model for the dialyzer. The model predicted the toxin concentration inside the body during blood purification therapy, and the toxin removal efficiencies at different flow configurations were compared quantitatively. According to the simulation results, the clearances of urea and ${\beta}_2$ microglobulin (B2M) using a pulsatile pump were improved by up to 30.9% for hemofiltration, with a 2.0% higher urea clearance and 4.6% higher B2M clearance for high flux dialysis, and a 3.9% higher urea clearance and 8.2% higher B2M clearance for hemodiafiltration. These results suggest that using a pulsatile blood pump in blood purification systems with a semipermeable membrane improves the efficacy of toxin removal, especially for large molecules and hemofiltration treatment.