• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.197-202
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• 2006

[ $^{11}B$ ] nuclear magnetic resonance (NMR) measurements were performed on the single crystals of $TbB_4$ to investigate local electronic structure and 4f spin dynamics. $^{11}B$ NMR spectrum, Knight shift, spin-lattice and spin-spin relaxation rates were measured down to 4K at 8T. $^{11}B$ NMR shift and linewidth are huge and strongly temperature dependent due to the 4f moments. In addition, both are proportional to magnetic susceptibility, indicating that the hyperfine field at the boron site originates from the 4f spins of Tb. Below $T_N$, the single broad resonance peak of $^{11}B$ NMR splits into several peaks reflecting the local magnetic fields due to antiferromagnetic spin arrangements. The longitudinal and the transverse relaxation rates, $1/T_1\;and\;1/T_2$, independent of temperature above $T_N$, decreases tremendously confirming huge suppression of spin fluctuation below $T_N$.

• Korean Journal of Veterinary Service
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• v.18 no.2
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• pp.177-181
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• 1995

The effects of histamine were investigated on the uterine smooth muscle motility in the pig. The results were summarized as fellows : 1. Histamine caused the contraction of the porcine uterine smooth muscle and the contractile responses increased between the concetration of histamine $10^{-8}$ and $10^{-5}$ M with a dose-dependent manner. 2. The contractile response Induced by histamine ($10^{-6}$ M) was completely blocked by pretrevatment with $H_1$-histaminergic receptor blocker, pyrilamine($10^{-6}$ M) 3. The contractile response induced by histamine($10^{-6}$ M) was increased by pretreatment with $H_2$-histaminergic receptor blocker, cimetidine($10^{-6}$ M) From these results, it was concluded that the effects of uterine smooth muscle by histamine were the contraction mediated by $H_1$-histaminergic receptor and the relaxation mediated by $H_2$-histaminergic receptor in pig.

• Journal of Sasang Constitutional Medicine
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• v.1 no.1
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• pp.171-181
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• 1989

We have studied some effects of the SOYANGIN-HYEONGBANGPAEDOK-SAN (S.H.P.). Several empirical remarks, depending on the different treatments, are investigated through this study as follow; 1. The Analgesic effects of S.H.P. are remarked by Acetic acid method in mice, 100 and 300mg/kg (Sample II, III), 2. The Antipyretic effect of S.H.P. are remarked by yeast method in rats, 100 and 300mg/kg (Sample II, III). 3. The inhibitory effects of S.H.P. on strychnine induced convulsion in mice is remarked. However the inhibitory effects of S.H.P. on picrotoxin induced convulsion in mice is not observed. 4. The effects of S.H.P. on muscle relaxation in mice, using the Rota-Rod test, is remarked on 1,2,3 hours by 300mg/kg (Sample III).

• Korean Journal of Pharmacognosy
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• v.37 no.2 s.145
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• pp.67-73
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• 2006

The butanol extracts of Agrimonia pilosa (BAP) induced dose-dependent vascular relaxation of phenylephrine-precontracted aorta, which was abolished by removal of functional endothelium. Pretreatment of the endothelium-intact aortic tissues with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 1H-[1,2,4]-oxadiazole-[$4,3-{\alpha}$]-quinoxalin-1-one(ODQ) inhibited the relaxation induced by BAP. BAP-induced vascular relaxation was also markedly attenuated by addition of verapamiI, while the relaxant effect of BAP was not blocked by indomethacine, glibenclamide, tetraethylammonium (TEA), atropine, or propranolo. In addition, incubation of endothelium-intact aortic rings with BAP increased the vascular production of cGMP. These results suggest that BAP relaxes vascular smooth muscle via endothelium-dependent nitric oxide/cGMP signaling pathway, which may be causally related with L-type $Ca^{2+}$ channels.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1166-1173
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• 2006

The aqueous extracts of Cortex Caryophylli (AEC) induced dose-dependent relaxation of phenylephrine-precontracted aorta, which was abolished by removal of functional endothelium. Pretreatment of the endothelium-intact aortic tissues with N$^G$_nitro-L-arginine methyl ester (L-NAME) or 1 H-[1,2,4]-oxadiazole-[4,3-${\alpha}$l-quinoxalin-1-one (ODQ) inhibited the relaxation induced by AEC. AEC-induced vascular relaxations were also markedly attenuated by addition of verapamil, diltiazem and glibenclamide, tetraethylammonium (TEA), respectively, while the relaxation effect of AEC was not blocked by indomethacin, atropine, or propranolol. Moreover, incubation of endothelium-intact aortic rings with AEC increased the production of cGMP. These results suggest that AEC dilates vascular smooth muscle via endothelium-dependent nitric oxide/cGMP signaling, which seems to be causally related with L-type Ca$^{2+}$ and K$^+$ channels.

• Investigative Magnetic Resonance Imaging
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• v.15 no.1
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• pp.48-56
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• 2011

Purpose : The aim of this study is to measure the typical MR variables such as $T_1$- and $T_2$-relaxation times according to morphological characteristics of gold nanopartides as a preliminary study to perform theragnosis using local heating by gold nanopartides. Materials and Methods : Two types of gold nanoparticles were used. Spheres were synthesized by various methods and stirring speed. Rods were synthesized by adding various concentrations of sphere nanopartides. Gold nanopartides were mixed with 2% agarose gel at 1:1 ratio and then signals were acquired using a 1.5T MRI. For the measurements of $T_1$-and $T_2$-relaxation times, TR and TE were varied, respectively. The results were acquired through $T_1$ and $T_2$ curves based on the intensities of MR image using self-developed software. And Statistical analysis was performed. Results : $T_1$ times were measured 1.86 sec and 2.08 sec for sphere and rod, respectively. On the other hands, $T_2$ times were measured 57 ms and 35.45 ms for sphere and rod. Conclusion : The changes of the MR variables according to the morphological characteristics of the gold nanopartides were confirmed. Optimal MR imaging conditions can be obtained by choosing proper TR and TE according to the type of nanoparticles.

• Journal of Korean Physical Therapy Science
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• v.26 no.2
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• pp.38-45
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• 2019

Purpose: This study purpose to comparison the effects of passive scapular alignment exercise and hold & relaxation technique on craniovertebral angle (C1~C7) with forward head posture due to using variety bag and using computer in healthy subjects. Design: Randomized Controlled Trial. Methods: 22 subjects were divide into two groups: PSAEx group and H/R group two groups. After exercise, the CVA were measured using C7 and tragus. Collected data were statistically analyzed by SPSS 20.2 Results: There were significant differences pre and post the exercise. Conclusion: PSAEx and H/R technique was effective to correct a abnormal CVA posture. The result of this study may helpful as basic data for orthopedic physical therapy.

• Journal of the Korean Vacuum Society
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• v.5 no.1
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• pp.73-76
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• 1996

We have prepared hydrogenated amophous silicon (a-si : H) films with superlattice structure by hydrogen radical anneling(HRA) technique. We have studied the preparation of a-Si :H films by HRA and the optical & electronic characteristics. Optical band gap and the hydrogen contents in the a Si : H film is decreased as HRA time increased. We first report a -Si : H film prepared by periodicdeposition of a-Si : H layer and HRA have the superlattice structure using TEM . After 1 hour light soaking on the a-Si :H film prepared by HRA, there are no difference in the temperatre dependence of dark conductivity and the conductivity activation energy. An excellent stability for light in a-Si :H films by HRA can be explained using the long-range structural relaxation of the amorphous network and the propertiesof light -induced defects(LID) proposed by Fritzsche.

• The Journal of the Acoustical Society of Korea
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• v.36 no.6
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• pp.387-393
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• 2017

The dynamic interactions between benzoic acid derivative ($pH{\approx}7.0$)(guest) and ${\beta}$-cyclodextrin (${\beta}$-CD)(host) were investigated in an aqueous solutions in terms of ultrasonic absorption in the frequency range 0.2 MHz ~ 50 MHz with emphasis on the low-frequency range below 1 MHz at $25^{\circ}C$. We show that the interaction of ${\beta}$-CD and benzoic acid derivative complies with a typical spectrum of a single relaxation process around a few MHz. The ultrasonic relaxation observed in these solutions was due to a perturbation of a chemical equilibrium related to a reaction of an inclusion complex formed by the host and guest. The rate constant ($k_b=7.48{\times}10^6M^{-1}s^{-1}$) and equilibrium constant ($K=68.6M^{-1}$) were determined from the concentration dependences of benzoic acid on the relaxation frequency. The standard volume change (${\Delta}V=10.6{\times}10^{-6}m^3mol^{-1}$) of the reaction was also computed from the maximum absorption per wavelength. It was found that the hydrophobicity of guest molecules played an important role in the formation of the inclusion complex.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.160-161
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• 2005

The $(Sr_{1-x}Ca_x)TiO_3$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method with substitutional contents of Ca. The optimum conditions of RF power and $Ar/O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin film was about 18.75$[{\AA}/min]$. The dielectric constant was increased with increasing the substitutional contents of Ca, while it was decreased if the substitutional contents of Ca exceeded over 15[mol%]. All SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].