• Journal of the Korean Society of Visualization
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• v.15 no.3
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• pp.14-19
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• 2017

Increase of blood viscosity significantly changes the flow resistance and wall shear stress which are related with cardiovascular diseases. For measurement of blood viscosity, microfluidic method has proposed by monitoring pressure between sample and reference flows in the downstream of a microchannel with two inlets. However, it is difficult to apply this method to unknown flow conditions. To measure blood viscosity under unknown flow conditions, a microfluidic method based on micro particle image velocimetry(PIV) is proposed in this study. Flow rate in the microchannel was estimated by assuming velocity profiles represent mean value along channel depth. To demonstrate the measurement accuracy of flow rate, the flow rates measured at the upstream and downstream of a T-shaped microchannel were compared with injection flow rate. The present results indicate that blood viscosity could be reasonably estimated according to shear rate by measuring the interfacial width and flow rate of blood flow. This method would be useful for understanding the effects of hemorheological features on the cardiovascular diseases.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.4
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• pp.139-143
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• 2013

In 2008, according to Statistics Korea's population over the age of 20 and 26.3% of the smokers, 73.7% were non-smokers, smokers and non-smokers by smoking of 22.0% was reported. 336 people of 255 people (75.9%) is currently also showed that smoking. Hypertension, 48 people(14.30%), the boundary type of high blood pressure 193 people (57.40%) of them, especially for high blood pressure appear as a systematic management is required. 336 people targeting taxi drivers smoking and blood pressure, and the relevance of the reserch results did not show a statistically significant difference. Current smokers of 336 people surveyed 255 people (75.90%), respectively. Men over 15 years old in Korea smoking population (1990) was reported as 73.2%, Lee 2001, according etc. Korea 61.8% of the adult male smoking rate is quite high as compared to what is reported. Taxi drivers are working in very bad working conditions. The health of a taxi driver affect the safety of customers were considered.

• Korea-Australia Rheology Journal
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• v.16 no.3
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• pp.129-134
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• 2004

The aggregation characteristics of red blood cells (RBCs) were measured using a newly developed light-transmission slit rheometer. Conventional methods of RBC disaggregation such as the rotational Couette system were replaced with a pressure-driven slit flow system with a vibrational mechanism. Using a vibration generator, one can disaggregate the RBC aggregates stored in the slit. While shear stress decreases exponentially, instantaneous pressure and the transmitted light intensity were measured over time. Applying an abrupt shearing flow after disaggregation caused a rapid elongation of the RBCs followed by loss of elongation with the decreasing shear stress. While the shear stress is further decreasing, the RBCs start to re-aggregate and the corresponding transmitted intensity increases with time, from which the aggregation indices can be obtained using a curve-fitting program.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.42-44
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• 2005

Many cellular phone volunteer studies have been conducted since such a social issue is raised that the long time usage of cellular phone may increase health risk. While there were various volunteer studies using GSM cellular phone on heart rate and blood pressure at abroad, very few studies using CDMA phone were conducted in domestic and abroad. In this study, the volunteer groups of 21 adults were exposed at 300 mW for half an hour, and the physiological parameters such as blood pressure, heart rate, respiration rate, and skin impedance were measured. All the parameters' results did not reveal any differences between exposure and non-exposure conditions in adults.

• Journal of Environmental Science International
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• v.21 no.5
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• pp.605-611
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• 2012

The purpose of this study is to analyze psychological and physiological effects accordance with viewing and walking in the forest and urban area. In the result of measurement of physiological reactions in nervous system, viewing of the forest had a calming effect on the nervous system by reducing blood pressure and heart rate. The other hand, viewing and walking in the urban area compared to the forest area raised stress by increasing blood pressure and heart rate. In addition, viewing in forest area was effective in stress relief by noticeable reduction of the amylase concentration. In contrast, walking in the urban area was also confirmed an increase of stress by increasing the concentration of the amylase. A viewing and walking in forest area was effective in alleviating depressed on anxiety, anger, fatigue and confusion.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.127-135
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• 2023

Purpose : This study was performed to evaluate the effects of magnetic therapy (MT) on pain threshold, blood flow, and balance in patients with knee osteoarthritis. Methods : A single-blind, randomized controlled trial (RCT) was conducted with 30 patient with knee osteoarthritis. They were randomly allocated 2 groups; magnetic therapy group (MTG; n=15) and placebo magnetic therapy group (PG; n=15). The MTG group received 30 minutes magnetic therapy and 20 minute conservative physical therapy (Hotpack, ICT), magnetic therapy was conducted in magnetic therapy device (OM-100, NUGA, Korea). In the placebo magnetic group received 30 minutes placebo magnetic therapy and 20 minute conservative physical therapy. Each group performed 50 minutes a day 3 times a week for 8 weeks. The primary outcome pressure pain threshold test, blood flow, balance ability were measured by a pressure threshold meter (Commander algometer, JTECH medical, USA), laser dofler image (Moor LDI2-IR, Moor instruments, USA), balance measurement system (BioRescue, Marseille, France). The measurement were performed before and after the 8 weeks intervention period. Results : Both groups demonstrated significant improvement of outcome in pain threshold, blood flow, and balance ability during intervention period. magnetic therapy group revealed significant differences in pain threshold, blood flow, and balance as compared to the placebo magnetic therapy group groups (p<.05). Our results showed that magnetic therapy was more effective than placebo therapy on pain threshold, blood flow, and balance in patients with knee osteoarthritis. Conclusion : Our findings indicate that magnetic therapy can improve pain threshold, blood flow, and Balance, highlight the benefits of magnetic therapy. This study will be able to be used as an intervention data for recovering pain threshold, blood flow, and balance in patients with knee osteoarthritis.

• Journal of Preventive Medicine and Public Health
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• v.33 no.3
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• pp.343-348
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• 2000

Objectives : This study was conducted to integrate the results of studies assessing the association between chronic noise exposure and blood pressure. Methods : Using a MEDLINE search with noise exposure, blood pressure and hypertension as key words, we retrieved articles from the literature that were published from 1980 to December 1999. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers employed at a high noise level area 2) The paper should use average and cumulative noise exposure as method for exposure evaluation. 3) Blood pressure in each article should be reported in a continuous scale Among the 77 retrieved articles, six studies were selected for quantitative meta-analysis. Before the integration of the regression coefficients for the association between blood pressure and noise level, homogeneity tests were conducted. Results : All studies were a cross-sectional design and the study subjects were industrial workers. Five papers used a time-weighted average for noise exposure and only one paper calculated the cumulative noise exposure level. The measurement of blood pressure in the majority of studios were accomplished in a resting stale, and used an average of two or more readings. The homogeneity of studies was rejected in a fixed effect model, so we used the results in a random effect model. The results of the quantitative meta-analysis, the weighted regression coefficient of noise associated with systolic blood pressure and diastolic blood pressure were 0.05 (95% confidence interval [CI]: -0.03, 0.13) and 0.06 (95% CI: -0.01, 0.13), respectively. Conclusions : Our results suggested that chronic exposure to industrial noise does not cause elevated blood pressure.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.9-23
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• 2024

This study investigates the physiological and psychological effects of a nature-based outdoor activity program in an environment reflecting the characteristics of forest and coastal areas on 30 firefighters (average age: 40.4 ± 9.8 years) who are frequently exposed to dangerous situations. Blood pressure, pulse pressure, and heart rate variability were used as physiological measurement indicators, and the Korean versions of PANAS (positive affect and negative affect schedule), WEMWBS (Warwick-Edinburgh mental well-being scale), and PRS (perceived restorativeness scale) were used as psychological measurement indicators. For four days and three nights, the participants experienced programs at Hallyeohaesang Nature Center and the surrounding mountains, seas, and islands, utilizing forest resources such as trekking on forest trails, walking barefoot, taking aromatic footbaths, meditating in forest oxygen domes, and lying on relaxation chairs, and programs utilizing marine resources such as taking a boat to an island, walking on forest trails with seascape views, and sailing on a yacht. Participants' systolic blood pressure and pulse pressure decreased, and participants' positive emotions increased and negative emotions decreased after the program. There was a statistically significant increase in mental well-being and perceived restorative environment. Through this study, it was found that nature-based outdoor activity programs based on forest and marine resources are effective in physiological and psychological stability of firefighters. It is hoped that the results of this study will be applied to other high-risk workers for PTSD, who have high stress levels, by combining forest healing and marine healing, and expanding the scope and diversity of programs in more diverse environments and conditions.

• Journal of Korean Academy of Nursing
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• v.28 no.4
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• pp.856-868
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• 1998

The purpose of this study is to evaluate the effects of Qigong gymnastics exercise program on the physiopsychological parameter in essential hypertension. The design of the research was a one group pretest-posttest design. A total of 20 pateints with hypertension who were from forty to sixty-five years old participated in the study. The Qigong gymnastics program was carried out twice a week for thirty minutes or forty minutes for six weeks from 22, Sep. to 31, Oct. in 1997. In order to evaluate the effect of the Qigong gymnastics program physiological parameter (blood pressure, pulse rate, FVC, FEV1, Epinephrine, Norepinephrine, Cortisol) and psychological parameter(self-efficacy, Life satisfaction) were measured before and after the exercise program. Collected data was analyzed by the paired t-test with SAS package. The result are as follows : 1) There were significant decrease in systolic blood pressure and diastolic blood pressure, but there was no significant change in pulse rate. 2) There were no significant difference in FVC and FEV1 3) There were significant decrease in epinephrine, norepinephrine and cortisol. 4) There were significant improved in general self-efficacy and life satisfaction. 5) The effect of Qigong gymnastics program by measurement time on blood pressure and pulse rate were as follows : In a systolic blood pressure was gradually significant decreased from 1 week to 6 weeks and diastolic blood pressure was significantly decreased after 4weeks. But there was no significant change in pulse rate. This results suggest that Qigong gymnastics are an appropriate nursing intervention for clients with hypertension. For further research is necessary to reevaluate the effect with a letter experimental design and longer period than 8 weeks for the Qigong gymnastics program.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1224-1230
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• 2003

The purpose of this present study is to measure the changes of regional cerebral blood flow(rCBF) and blood pressure(BP) in rats. following the intravenous injection of drug. The measurement was continually monitored by laser-doppler flowmeter (Transonic Instrument, USA) and pressure tranducer(Grass, USA) in anesthetized adult Sprague-Dawley rats about for 2h to 2h and a half through the data acquisition system composed of MacLab and Macintosh computer. The result of this experiment was as following. 1. Fructus Schizandrae increased the changes of rCBF in rats, significantly. 2. The rCBF of Fructus Schizandrae did not change by pretreated propranolol. 3. The rCBF of Fructus Schizandrae did not change by pretreated atropine. 4. The rCBF of Fructus Schizandrae did not change by pretreated I-NNA. 5. The rCBF of Fructus Schizandrae was decreased by pretreated methylene blue. 6. The rCBF of Fructus Schizandrae did not change by pretreated indomethacin. 7. Fructus Schizandrae decreased the changes of blood pressure significantly. 8. The BP of Fructus Schizandrae did not change by pretreated propranolol. 9. The BP of Fructus Schizandrae did not change by pretreated atropine. 10. The BP of Fructus Schizandrae did nol change by pretreated I-NNA. 11. The BP of Fructus Schizandrae was decreased by pretreated methylene blue. 12. The BP of Fructus Schizandrae did not change by pretreated indomethacin. These results indicate that Fructus Schizandrae can increase the rCBF and decrease the BP, that related to guanylyl cyclase activity.