• 제목/요약/키워드: System Relaxation

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Pharmacological Actions of New Woohwangchungsimwon Liquid on Cardiovascular System (신우황청심원액의 심혈관계에 관한 약효연구)

  • 조태순;이선미;김낙두;허인회;안형수;박대규
    • Biomolecules & Therapeutics
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    • v.5 no.4
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    • pp.390-401
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    • 1997
  • In order to investigate the pharmacological properties of New Woohwangchungsimwon Liquid (NCL), effects of Woohwangchungsimwon Liquid (CL) and NCL were compared. In isolated rat aorta, NCL and CL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) without regard to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxation of NCL and CL. NCL and CL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NCL and CL significantly decreased heart rate. NCL and CL, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NCL and CL had no effects on parameters of action potential at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NCL and CL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between two preparations.

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Early Stage Growth Structure and Stress Relaxation of CoCrPt Thin Films on Spherically Modulated Polymer Surface

  • Kim, Sa-Rah;Jeong, Jun-Ho;Shin, Sung-Chul;Son, Vo Thanh;Jeon, Bo-Geon;Kim, Cheol-Gi;Jeong, Jong-Ryul
    • Journal of Magnetics
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    • v.15 no.1
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    • pp.12-16
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    • 2010
  • Combined study of in-situ stress measurements and atomic force microscopy (AFM) revealed drastic stress relaxation in the CoCrPt and PS(styrene)-PVP(vinyl pyridine) polymer hybrid structure that was closely related to the growth structure of the film. We have observed not only no large initial growth stress at the initial stages of film growth but also twice smaller stress in magnitude with opposite sign in the CoCrPt/PS-PVP/Si sample. The microstructural studies using AFM at the various film growth stages revealed that the film growth structure plays an important role in the stress relaxation mechanism of CoCrPt films on a corrugated polymer surface.

An NMR Study on Molecular Motions of $\alpha$,2,6-Trichlorotoluene in Solution State

  • Ahn, Sang-Doo;Lee, Jo-Woong
    • Bulletin of the Korean Chemical Society
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    • v.15 no.7
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    • pp.553-559
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    • 1994
  • Dynamics of $CH_2CI$ group in ${\alpha},2,6$-trichlorotoluene dissolved in $CDCl_3$ was studied by observing various relaxation modes for $^{13}C$ under proton undecoupled condition. Partially relaxed $^{13}C$ spectra were obtained at $34^{\circ}C$ as a function of evolution time after applying various designed pulse sequences to this $AX_2$ spin system. It was found that nonlinear regression analysis of the relaxation data for these magnetization modes could provide the information about dipolar and spin-rotational auto-correlation and cross-correlation spectral densities for fluctuation of the $^{13}C-^1H$ internuclear vector in $CH_2Cl$ group. The results show that the effect of cross-correlation is comparable in magnitude to that of auto-correlation and the relaxation in this spin system is dominated by dipolar mechanism rather than spin-rotational one. From the resulting spectral density data we could calculate the bond angle ${\angle}HCH\;(105.1$^{\circ}$) and elements of the rotational diffusion tensor for $CH_2Cl$ group.

A research on EEG coherence variation by relaxation (이완에 따른 EEG 코히런스 변화에 대한 연구)

  • Kim, Jong-Hwa;Whang, Min-Cheol;Woo, Jin-Cheol;Kim, Chi-Joong;Kim, Young-Woo;Kim, Ji-Hye;Kim, Dong-Keun
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.121-128
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    • 2010
  • This study is to analyze change of connectivity between brain positions caused by relaxation through EEG coherence. EEG spectrum analysis method has been used to analyze brain activity when relaxation was experienced. However, the spectrum analysis method has a limit that could not observe interactive reaction between brain-functional positions. Therefore, coherence between positions was analyzed to observe connectivity between the measurement positions in this study. Through the method, the reaction of the central nervous system caused by the emotion change was observed. Twenty-four undergraduates of both genders(12 males and 12 females) were asked to close their eyes and listen to the sound. During experiment, EEG was measured at eight positions. The eight positions were F3, F4, T3, T4, P3, P4, O1, and O2 in accordance with International 10-20 system. The sounds with white noise and without were used for relaxation experience. Subjective emotion was measured to verify whether or not they felt relaxation. Subjective emotion of participants were analyzed by ANOVA method(Analysis of Variance). In the result, it was proved that relaxation was subjectively evoked when participants heard sound. Accordingly, it was proved that relaxation could be enhanced by the mixed white noise. EEG coherence between the measurement positions was analyzed. T-test was performed to find its significant difference between relaxation and not-relaxation. In the results of EEG coherence, connectivity with occipital lobes has been increased with relaxation, and connectivity with parietal lobes has been increased with non-relaxed state. Therefore, brain connectivity has shown different pattern between relaxed emotion and non-relaxed emotion.

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Sensitivity illumination system using biological signal (생체신호를 이용한 감성조명 시스템)

  • Han, Young-Oh;Kim, Dong-Woo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.4
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    • pp.499-508
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    • 2014
  • In this paper, we implemented a LED sensitivity illumination system, being driven in response to changes in the biological signals of GSR and PPG signal. After measuring biological signals of a human body from GSR and PPG sensor modules, MCU decided the state of relaxation or arousal of the subject, being based on the wake relaxation identifying map proposed in this paper. A developed LED sensitivity illumination system makes the subject to reach a normal state by giving a change of the LED illumination color, corresponding to a state of the subject.

Studies on the Efficacy of Combined Preparation of Crude Drug (XIX) -The effect of ‘Samulanshintang’ on the Cardiovascular System and Anemic Rabbits induced by Phenylhydrazine- (생약복합제제(生藥複合製劑)의 약효(藥效) 연구(硏究) (제19보)(第19報) -사물안신탕(四物安神湯)이 순환기계(循環器系) 및 Phenylhydrazine으로 유발(誘發)된 가토빈혈(家兎貧血)에 대한 영향(影響)-)

  • Hong, Nam-Doo;Lee, Kyung-Sup;Whang, Wei-Wan;Kim, Nam-Jae
    • Korean Journal of Pharmacognosy
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    • v.15 no.4
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    • pp.188-193
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    • 1984
  • It was previously indicated that 'Samulanshintang' had been examined for effects of the anticonvulsive, antipyretic, analgesic, sedative and antispasmodic actions. In order to investigate the effect on the cardiovascular system and anemic rabbits induced by phenlhydrazine HCl, pharmacological studies have been carried out with extract. The results of this investigation were summarized as follows: The relaxation of bronchial smooth muscle and antihistamine action were recognized. Antihypertensive and vasodilating actions due to vascular smooth muscle relaxation were noted in frogs and rabbits. 'Samulanshintang' lowered the rate of anemia induced by phenylhydrazine and rapidly recovered from the anemia state.

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Detection of Iron Nanoparticles using Nuclear Magnetic Resonance Relaxometry and Inverse Laplace Transform

  • Kim, Seong Min
    • Journal of Biosystems Engineering
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    • v.39 no.4
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    • pp.345-351
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    • 2014
  • Purpose: Rapid detection of bacteria is very important in agricultural and food industries to prevent many foodborne illnesses. The objective of this study was to develop a portable nuclear magnetic resonance (NMR)-based system to detect foodborne pathogens (E. coli). This study was focused on developing a method to detect low concentrations of magnetic nanoparticles using NMR techniques. Methods: NMR relaxometry was performed to examine the NMR properties of iron nanoparticle mixtures with different concentrations by using a 1 T permanent magnet magnetic resonance imaging system. Exponential curve fitting (ECF) and inverse Laplace transform (ILT) methods were used to estimate the NMR relaxation time constants, $T_1$ and $T_2$, of guar gum solutions with different iron nanoparticle concentrations (0, $10^{-3}$, $10^{-4}$, $10^{-5}$, $10^{-6}$, and $10^{-7}M$). Results: The ECF and ILT methods did not show much difference in these values. Analysis of the NMR relaxation data showed that the ILT method is comparable to the classical ECF method and is more sensitive to the presence of iron nanoparticles. This study also showed that the spin-spin relaxation time constants acquired by a Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence are more useful for determining the concentration of iron nanoparticle solutions comparwith the spin-lattice relaxation time constants acquired by an inversion recovery pulse sequence. Conclusions: We conclude that NMR relaxometry that utilizes CPMG pulse sequence and ILT analysis is more suitable for detecting foodborne pathogens bound to magnetic nanoparticles in agricultural and food products than using inversion recovery pulse sequence and ECF analysis.

Comparison of the Flexion-Relaxation Ratio of the Hamstring Muscle and Lumbopelvic Kinematics During Forward Bending in Subjects With Different Hamstring Muscle Flexibility

  • Kim, Chang-ho;Gwak, Gyeong-tae;Kwon, Oh-yun
    • Physical Therapy Korea
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    • v.24 no.4
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    • pp.1-10
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    • 2017
  • Background: Flexion-relaxation phenomenon (FRP) was a term which refers to a sudden onset of myoelectric silence in the erector spinae muscles of the back during standing full forward flexion. Hamstring muscle length may be related to specific pelvic and trunk movements. Many studies have been done on the FRP of the erector spinae muscles. However, no studies have yet investigated the influence of hamstring muscle flexibility on the FRP of the hamstring muscle and lumbopelvic kinematics during forward bending. Objects: The purpose of this study was to examine the flexion-relaxation ratio (FRR) of the hamstring muscles and lumbopelvic kinematics and compare them during forward bending in subjects with different hamstring muscle flexibility. Methods: The subjects of two different groups were recruited using the active knee extension test. Group 1-consisted of 13 subjects who had a popliteal angle under $30^{\circ}$; Group 2-consisted of 13 subjects who had a popliteal angel above $50^{\circ}$. The kinematic parameters during the trunk bending task were recorded using a motion analysis system and the FRRs of the hamstring muscles were calculated. Differences between the groups were identified with an independent t-test. Results: The subjects with greater hamstring length had significantly less lumbar spine flexion movement and more pelvic flexion movement. The subjects with greater pelvic flexion movement had a higher rate of flexion relaxation during full trunk bending (p<.05). Conclusion: The results of this study suggest that differences in hamstring muscle flexibility might cause changes in people's hamstring muscle activity and lumbopelvic kinematics.

Effects of DaeSiHo-Tang extract on Hypertension and Arterial Contraction (대시호탕(大柴胡湯)이 고혈압과 수축혈관에 미치는 영향)

  • Yeo Un-Hong;Jo Hak-Jun;Kim Ho-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1573-1579
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    • 2005
  • This study was undertaken to define the effect of DaeSiHo-Tang extract on the hypertension in spontaneous hypertensive rat and norepinephrine-induced arterial contraction in rabbit. Systolic blood pressure and blood velocity were significantly attenuated by administration of DaeSiHo-Tang extract. but blood flow and renin-angiotensin-aldosterone system unaffected by DaeSiHo-Tang extract. The relaxation effect of DaeSiHo-Tang extract was dependent on the presence of endothelium, showing that DaeSiHo-Tang extract-induced relaxation was not observed in the strips without endothelium. The endothelium-dependent relaxation induced by DaeSiHo-Tang extract was decreased by the pretreatment of $N{\omega}$-nitro-L-arginine or methylene blue, but it was not observed in the strips pretreated with indomethacin or tetraethylammonium chloride. When $Ca^{2+}$ was applied, the strips which were contracted by norepinephrine in a $Ca^{2+}$-free solution, arterial contraction was increased. But pre-treatment of DaeSiHo-Tang extract inhibited contractile response to $Ca^{2+}$. These results indicate that antihypertensive effect of DaeSiHo-Tang extract is due to descend arterial resistance by the arterial relaxation through the formation of nitric oxide in the vascular endothelial cells.

Effect of lithium on endothelial-dependent relaxation to melatonin in rat aorta (흰쥐 대동맥에서 melatonin의 내피 의존적 혈관 이완 작용에 대한 lithium의 영향)

  • Kim, Shang-Jin;Yu, Xianfeng;Cho, In-Gook;Kang, Hyung-Sub;Kim, Jin-Shang
    • Korean Journal of Veterinary Research
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    • v.45 no.4
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    • pp.553-562
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    • 2005
  • Melatonin, the principal hormone of the vertebral pineal gland, participates in the regulation of cardiovascular system in vitro and in vivo. Lithium inhibits both inositol polyphosphate phosphatase (IPPase) and inositol monophosphatase (IMPase), which are involved in a wide range of signal transduction pathways. The aim of the present study was to assess the effect of lithium on endothelial-dependent relaxation to melatonin and on the melatonin-induced inhibition of contraction by phenylephrine (PE) in isolated rat aorta. Melatonin induced a concentration-dependent relaxation in PE-precontracted in endothelium-intact (+E) aortic rings. Melatonin inhibited a PE-induced sustained contraction in +E aortic rings. These effects of melatonin on relaxation and contractile responses were inhibited by pretreatment with lithium. In PE-precontracted +E aortic rings, the melatonin-induced vasorelaxations and the inhibitory effects of melatonin on maximal contractions were inhibited by endothelium removal or by pretreatment with L-$N^G$-nitro-arginine (L-NNA), 1H-[1,2,4] oxadiazolo-[4,3-a] quinoxalin-1-one (ODQ) and nifedipine and verapamil, but not by tetrabutylammonium, clotrimazole and glibenclamide, However, in endothelium-denuded (-E) aortic rings and in the presence of L-NNA and ODQ in +E aortic rings, the melatonin-induced residual relaxations and the melatonin-induced residual contractile responses to PE were not affected by lithium. It is concluded that the inositol phosphate pathway may be involved in endothelial-dependent relaxation induced by melatonin.