• The Korean Journal of Physiology
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• v.24 no.1
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• pp.51-65
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• 1990

The purpose of the present study was to examine the hemodynamic responses, especially in arterial and skin blood flows, in conjunction with the changes of plasma catecholamine levels as an indirect marker of adrenergic tone during the early stage of head-down tilt (HDT), and to evaluate the early physiological regulatory mechanism in simulated weightlessness. Ten mongrel dogs, weighing8\;{\sim}\;14\;kg, were intravenously anesthetized with nembutal, and postural changes were performed by using the tilting table. The postural changes were performed in the following order: supine, prone, HDT $(-6^{\circ}C)$ and lastly recovery prone position. The duration of each position was 30 minutes. The measurements were made before, during and after each postural change. The arterial blood flow $({\.{Q}})$ at the left common carotid and right brachial arteries was measured by the electromagnetic flowmeter. Blood pressure (BP) was directly measured by pressure transducer in the left brachial artery. To evaluate the peripheral blood flow, skin blood flow $({\.{Q}})$ was calculated by the percent changes of photoelectric pulse amplitude on the forepaw, and skin temperature was recorded. The peripheral vascular resistance (PR) was calculated by dividing respective mean BP values by ${\.{Q}}$ of both sides of common carotid and brachial arteries. Heart rate (HR), respiratory rate (f) and PH, $Po_{2},\;Pco_{2}$ and hematocrit of arterial and venous blood were also measured. The concentration of plasma epinephrine and norepinephrine was measured by radioenzymatic method. The results are summarized as follows: Tilting to head-down position from prone position, HR was initially increased (p<0.05) and BP was not significantly changed. While ${\.{Q}}$ of the common carotid artery was decreased (p<0.05) and PR through the head was increased, ${\.{Q}}$ of the brachial artery was increased (p<0.05) and PR through forelimbs was decreased. ${\.{Q}}$ of the forepaw was initially increased (p<0.05) and then slightly decreased, on the whole revealing an increasing trend. Plasma norepinephrine was slightly decreased and the epinephrine was slightly increased. f was increased and arterial pH was increased (p<0.05). In conclusion, the central blood pooling during HDT shows an increased HR via Bainbridge reflex and an increased ${\.{Q}}$ of the forepaw and brachial ${\.{Q}}$, due to decreased PR which may be originated from the depressor reflex of cardiopulmonary baroreceptors. It is suggested that the blood flow to the brain was adequately regulated throughout HDT $(-6^{\circ}C)$ in spite of central blood pooling. And it is apparent that the changes of plasma norepinephrine level are inversely proportional to those of ${\.{Q}}$ of the forepaw, and the changes of epinephrine level are paralleled with those of the brachial ${\.{Q}}$.

• Journal of Convergence for Information Technology
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• v.8 no.1
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• pp.131-138
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• 2018

The purpose of the study was to explore whether the Cyber Motion sickness used VR causes a change in the dynamic balance and fall. For 39 people who voluntarily participated in this study, this study measured the motion sickness questionnaires, the heart rate and stability of limit test in BioRescue. The study used Samsung Gear VR and applied the games to the To the homeland. The game proceeded 20minutes. Although the value of the stability after a VR application is slightly reduced, it did not reach statistical significance. The motion sickness questionnaires increased, and it had a statistical significant impact. Also Heart rate increased and it had a statistically significant impact. A virtual reality game affect for getting motion sickness but it did not affect the dynamic balance. So, cyber motion sickness caused by virtual reality wear does not result in decreased balance and falls.

• Journal of Radiation Protection and Research
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• v.11 no.1
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• pp.3-14
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• 1986

A stud has been carried out for figuring out real photon spectrum from an observed gamma-ray spectrum by means of response matrix method, which is known one of the relatively convenient method for the estimation of exposure rate of a complex gamma ray field in comparison with graphical analysis and least square fitting of the measured spectrum. A 3'${\times}$3' cylindrical Nal(T1) scintillation detector in association with multichannel pulse height analyzer and six reference gamma ray sources covering the photon energy range of 0.05 to 2.0 MeV were used. In dividing the energy region for the construction of response matrix, two different approaches were attempted. One is dividing the entire energy region of interest into 20 bins, one of which corresponds to a width of 0.1 MeV to form $20{\times}20$ matrix, and another is dividing the 2 MeV region into 14 bins to form $14{\times}14$ matrix consists of $0.1(MeV)^{1/2}$ intervals assuming the resolution of the detector is dependent on square root of the incident photon energy. Inversion of thus constructed matrices was performed by a computor(P-E8/32) using the program attached to the end of this paper. The resultant exposure rates obtained by this method were in good agreement, within 10% with those calculated by ordinary formula widely used for a gamma-ray field of known energy and flux. It is concluded that the photen flux obtained by the response matrix constructed under the assumption of $E^{1/2}$ dependence is more realistic than that obtained by the matrix consist of identical energy bins in dosimetrical point of view.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.664-669
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• 2014

This research was conducted to investigate the impact of viewing scenery and walking in the urban forest on physiological relaxation of humans. The experiment was conducted in Hanbat Arboretum located in Daejeon, and the control experiment was conducted in front of Daejeon City Hall. The subjects that participated in the experiment comprised 24 Korean male university students in their 20s (average age, $21.1{\pm}2.5years$), participated in the experiment as the subject, and these subjects were classified into three groups divided into three locations such as the pine forest in Arboretum, the pond in Arboretum, and the city. The subjects sat down and viewed scenery for 10 min, and they then walked for 15 min. Further, physiological changes were measured using indicators such as heart rate variability (HRV), blood pressure, and pulse rate. As a result, when subjects viewed scenery and walked in the urban forest, a statistically significant increase in the high frequency (HF) power of HRV and decrease in systolic pressure was observed compared with when subjects viewed scenery and walked in the city. Through this research, it was found that activities like viewing scenery or walking in Arboretum of the city are effective in increasing the physiological relaxation of the city residents.

• Child Health Nursing Research
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• v.19 no.3
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• pp.198-206
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• 2013

Purpose: This study was done to identify the effectiveness of the 'intervention - mother's recorded song' on low-birth weight infants in an neonatal intensive care unit (NICU). Methods: This study was conducted with a nonequivalent control group pre-posttest quasi-experimental design and the participant group was low-birth weight infants who were admitted to the NICU. Forty-eight infants, 24 in each from two groups, the experimental and control group, participated in the study. Results: For physical response according to vital signs, there were no significant statistical differences in heart rate, respiration rate and pulse oximetry saturation between the experimental group and the control group. For behavioral state, there was a significant statistical difference between the experimental and control group. Conclusion: The study results indicate that the intervention using mother's song had some significance as a nursing intervention with positive impacts. Such an intervention can help pediatric nurses improve infants' stabilization of their vital signs and behavioral states. By showing the effectiveness of such an intervention, the results of this study provide further evidence-based information in developing the practice of pediatric nursing.

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.159-184
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• 1998

The aim of the study was the experiment of the effect that Kami-Daesihotang had on the essential hypertension and hyperlipidemia. Rats were orally administered with Kami-Daesihotang for 30days and the constituent of the plasma and serum were analysed at the 10th, 20th and 30th day from the first day of experiment, respectively. The heart rate, blood pressure, plasma renin activity, plasma level of aldosterone, catecholamine, sodium and angiotensin II were measured after an oral administration of Kami-Daesihotang in SHR. In addition, serum levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and total lipid were measured with cholesterol-fed rats. The results were summarized as following ; 1. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang remarkably decreased the blood pressure in SHR. 2. Double-dosage Kami-Daesihotang were recognized as having the effect on the decreased of the pulse rate in SHR. 3. Plasma renin activity was significantly decreasd in SHR after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 4. Double-dosage Kami-Daesihotang considerably reduced the plasma angiotensin level in SHR. 5. Noticeable decreased of plasma norepinephrine level was showed in SHR, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 6. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang noticeable reduced body weight in hyperlipidemia rats which had fed with 1% cholesterol. 7. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang had a significantly decreasing effect on serum total cholesterol in hyperlipidemia rats which had fed with 1% cholesterol. 8. Serum triglyceride level was importantly decreased in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 9. Remarkable decreased of serum low density lipoprotein cholesterol level was found in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 10. Double-dosage Kami-Daesihotang was showed a significantly decreasing effect on serum total lipid level in hyperlipidemia rats which had fed with 1% cholesterol. 11. Single-dosage Kami-Daesihotang noticeably reduced organ weight of liver, kidney, spleen and testis in hyperlipidemia rats which had fed with 1% cholesterol. Double-dosage Kami-Daesihotang significantly decreased organ weight of liver, kidney and spleen in hyperlipidemia rats. These Findings suggest a possible anti-hypertensive and hyperlipidemic effect of Kami-Daesihotang.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1585-1592
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• 2016

The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.477-481
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• 2007

The emergency patient who occurs from the place where it is various the control which is quick must come to accomplish in Ubiquitous environment. In the body of the patient or the old person the organism signal sensor about under attaching condition of the patient at real-time about under the monitor ring about under disposing the control which is quick against the emergency patient does to become accomplished at the case real-time when the above will get in the body of the patient or the old person. Using ZigBee (802.15.4) system base on Shor wireless communication protocol because of complement wireless of hospital. This system use ZigBee (802.15.4) system to get for electrocardiogram, blood pressure and pulse bio-sensors. This paper constructs Bio-Sensor communication monitoring system and transmission rate and the delay which it follows possibility and node occurrence rate of wireless sensor network construction hour transmission session it leads and it verifies the effectiveness.

• The Korean Journal of Pain
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• v.1 no.1
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• pp.20-27
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• 1988

Continuous cervical epidural anesthesia with two different concentrations of bupivacaine had been performed in 43 cases for surgery of upper extremity and cervical spine. After the initial dose of 0.33% bupivacaine 15ml to Group I(n=22) and 0.5% bupivacaine 15ml to Group II(n=21) was injected respectively, we observed the circulatory and pulmonary functions to be changed, and evaluated the duration of those analgesic action. The number of spinal segment to be affected and the complications were checked. Statistical significance of changes after the initial dose in both groups was determined by student's t-test. All values are impresed as mean$\pm$1S.D.. The results were as follows: 1) Circulatory functions; Systolic B.P. and Pulse rate were decreased by 10~15torr and 5~6 beats per minute respectively between 10~30 minutes following the initial dose, which were statistically significant in both groups. 2) Pulmonary functions; The diminution of minute volume showed to 20% and a rise of $PaCO_2$ level to 5~6 torr respectively between 30~60 minutes following the initial dose, which were statistically significant in both groups. There were no significant changes in self respiration and respiratory rate in both groups. 3) The duration of analgesic action was $72.3{\pm}25.7$(min) in Group I and $83.5{\pm}28.5$(min) in Group II which was not statistically significant between two groups, and the number of affected spinal segment at ore hour following the Anesthusia was $8.7{\pm}2.0$ in Group I and $10.5{\pm}2.4$ in Group II which was statistically significant between two groups. 4) Complications; a. Hypotension(below 80torr in systolic pressure) was appeared in 5% of all patients. b. Bradycardia(below 60 beats per minutes) was appeared in 25% of all patients. c. Inadvertent dural puncture was developed in only one patient, In conclusion, the 0.33% bupivacaine as well as 0.5% bupivacaine were enough for those analgesic effect in the above mentioned surgery even though the duration of analgesic action was about 10 minutes shorter in Group I than that of Group II. The cardiopulmonary function was clinically rather stable in Group I than that of Group II. Therefore we thought 0.33% bupivacaine was satisfactory for the clinical practicality in the cervical epidural anesthesia.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.62-62
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• 2018

Pt is still considered as one of the most active electrocatalysts for ORR in alkaline fuel cells. However, the high cost and scarcity of Pt hamper the widespread commercialization of fuel cells. As a strong candidate for the replacement of Pt catalyst, silver (Ag) has been extensively studied due to its high activity, abundance, and low cost. Ag is more stable than Pt in the pH range of 8~14 as the equilibrium potential of Ag/Ag+ being ${\approx}200mV$ higher than that of Pt/PtO. However, Ag is the overall catalytic activity of Ag for oxygen reduction reaction(ORR) is still not comparable to Pt catalyst since the surface Ag atoms are approximately 10 times less active than Pt atoms. Therefore, further enhancement in the ORR activity of Ag catalysts is necessary to be competitive with current cutting-edge Pt-based catalysts. We demonstrate the architectural design of Ag catalysts, synthesized using plasma discharge in liquid phase, for enhanced ORR kinetics in alkaline media. An attractive feature of this work is that the plasma status controlled via electric-field could form the Ag nanowires or dendrites without any chemical agents. The plasma reactor was made of a Teflon vessel with an inner diameter of 80 mm and a height of 80 mm, where a pair of tungsten(W) electrodes with a diameter of 2 mm was placed horizontally. The stock solutions were made by dissolving the 5-mM AgNO3 in DI water. For the synthesis of Agnanowires, the electricfield of 3.6kVcm-1 in a 200-ml AgNO3 aqueous solution was applied across the electrodes using a bipolar pulsed power supply(Kurita, Seisakusyo Co. Ltd). The repetition rate and pulse width were fixed at 30kHz and 2.0 us, respectively. The plasma discharge was carried out for a fixed reaction time of 60 min. In case of Ag nanodendrites, the electric field of 32kVcm-1 in a 200-ml AgNO3 aqueous solution was applied and other conditions were identical to the plasma discharge in water in terms of electrode configuration, repetition rate and discharge time. Using SEM and STEM, morphology of Ag nanowires and dendrites were investigated. With 3.6 kV/cm, Ag nanowire was obtained, while Ag dendrite was constructed with 32 kV/cm. The average diameter and legth of Ag nanowireses were 50 nm and 3.5 um, and thoes values of Ag dendrites were 40 nm and 3.0 um. As a results of XPS analysis, the surface defects in the Ag nanowires facilitated O2 incorporation into the surface region via the interaction between the oxygen and the electron cloud of the adjacent Ag atoms. The catalytic activity of Ag for oxygen reduction reaction(ORR) showed that the catalytic ORR activity of Ag nanowires are much better than Ag nanodendrites, and electron transfer number of Ag nanowires is similar to that of Pt (${\approx}4$).