• Archives of Pharmacal Research
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• v.27 no.7
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• pp.763-768
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• 2004

To investigate the feasibility of developing a new quercetin transdermal system, a preformulation study was carried out. Therefore, the effects of vehicles and pressure-sensitive adhesives (PSA) on the in vitro permeation of quercetin across dorsal hairless mouse skin were studied. Among vehicles used, propylene glycol monocaprylate (PGMC) and propylene glycol mono-laurate were found to have relatively high permeation flux from solution formulation (i.e., the permeation fluxes were 17.25$\pm$1.96 and 9.60$\pm$3.87 $\mu\textrm{g}$/$\textrm{cm}^2$/h, respectively). The release rate from PSA formulations followed a matrix-controlled diffusion model and was mainly affected by the amount of PSA and drug loaded. The overall permeation fluxes from PSA formulations were less than 0.30 $\mu\textrm{g}$/$\textrm{cm}^2$/h, which were significantly lower compared to those obtained from solution formulations. The lower permeation fluxes may be due to the decrease of solubility and diffusivity of quercetin in the PSA layer, considering the fact that the highest flux of 0.26 $\mu\textrm{g}$/$\textrm{cm}^2$/h was obtained with the addition of 0.2％ butylated hydroxyanisole in PGMC-diethyl-ene glycol monoethyl ether co-solvents (80-85 ： 15-20, v/v). Taken together, these observations indicate that improvement in the solubility and diffusivity of quercetin is necessary to realize fully the clinically applicable transdermal delivery system for the drug.

• Korean Journal of Applied Biomechanics
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• v.28 no.4
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• pp.207-211
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• 2018

Objective: The purpose of this study was to examine the effects of an 8-week SMR, stretching, and band program on lower limb alignment (distance between the knees, Q angle) and gait (gait speed, stride length, impulse, and peak pressure) in female in their 20s who have genu varum. Method: The participants, female in their 20s who had genu varum, were randomly divided into the SMR, Stretching, and Band group (SSB, n=9), Stretching and Band group (SB, n=9), and Control Group (CG, n=9). Experimental group A (SSB) performed 3 50-minute sessions of the program per week for 8 weeks while the experimental group B (SB) performed stretching and band correctional exercise in 3 40-minute sessions per week for 8 weeks. The control group had no correctional exercise program. Results: Only the SSB group showed a significant increase in gait velocity and stride length in this study. The SSB and SB group showed a significant decrease of impulse on the forefoot after exercise program suggests that SMR and elastic band exercise had a positive effect on the distribution of foot pressure. Conclusion: We concluded that 8-week genu varum correctional exercise program had beneficial effects on the gait parameters (gait velocity, stride length, impulse, peak pressure) in 20s women with genu varum.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.217-225
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• 1993

The role of endogenous brain angiotensin ll (Ang ll) in mediating the cardiovascular and vasopressin responses to hemorrhage was assessed in conscious spontaneously hypertensive rats (SHR), and normotensive Wistar-Kyoto (WKY) rats. Artificial cerebrospinal fluid (aCSF) with or without losartan (DuP 753), a specific Ang ll receptor subtype I $(AT_1)$ antagonist and saralasin, a combined $AT_1/AT_2$ antagonist was administered into the cerebral lateral ventricle. Hemorrhage was performed at a rate of 3 ml/kg/min far 5 min. Intracerebroventricular administration of losartan and saralasin had no effect on the basal blood pressure. However, in response to acute hemorrhage, central Ang ll antagonists produced a remarkably greater fall in blood pressure, a reduced tachycardia, and an enhanced renin release compared with the aCSF control experiment in SHR, but effected no significant change in WKY rats. Central Ang ll-blocked SHR showed significantly lower blood pressure and heart rate during the recovery period than the aCSF control rats. Vasopressin release tallowing the hemorrhage was attenuated by icv Ang ll antagonists: the effect was more pronounced in SHR than in WKY rats. Centrally administered losartan and saralasin produced remarkably similar effects on the cardiovascular function and vasopressin responses to hemorrhage. These data suggest that brain Ang ll acting primarily through AT, receptors plays an important physiological role in mediating rapid cardiovascular regulation and vasopressin release in response to hemorrhage especially in Hypertensive rats.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.715-721
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• 1997

W/O/W multiple emulsions were prepared comprising $MgSO_4$ in the inner aqueous phase as a model drug. The stability and drug release behavior of the multiple emulsions were studied using optical microscopy, viscometry and conductometry. Glucose was introduced in the outer aqueous phase to reduce the osmotic pressure gradient across the oil layer arising from the localization of drug molecules in the inner water phase. It was found that the presence of glucose was effective in stabilization of the multiple emulsions and in control of the release rate of drug more evidently when oil phase was partially hydrophilized with cetostearyl alcohol. This may be attributed to the fact that the migration of water accompanying the hydrophilic surfactant to the inner water phase was limited under a reduced osmotic pressure gradient and thereby slow down the destabilization of the oil/inner water interface.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.8
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• pp.743-752
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• 2013

This is the second paper on the combustion characteristics of landfill gas in a constant volume combustion chamber for a large displacement volume commercial engine, and it discusses the combustion process on the basis of pressure measurements. The results show that the bimodal peak pressure phenomenon, which is caused by the interaction of the heat release and the heat transfer, is more apparent as the mixtures are more favorable to combustion, and the magnitudes of the pressures depend on the unburned fraction. In addition, there exist four main inflection points during heat release owing to variations in the heat transfer area related to flame propagation from the ignition point. Furthermore, the number of inflection points increases as the mixture quality worsens because of the extended burn duration. Consequently, the sophisticated interactions between the heat transfer area changing pattern due to flame propagation and transfer duration might cause very peculiar heat release patterns.

• Journal of the Korean Institute of Gas
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• v.18 no.3
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• pp.67-74
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• 2014

Buried natural gas pipelines in densely populated urban areas have serious hazards of property damages and casualties generated by release, dispersion, fire and explosion of gas caused by outside or inside failures. So as to prevent any accident in advance, managers implement danger management based on quantitative risk analysis. In order to evaluate quantitative risk about buried natural gas pipelines, we need calculation for radiant heat and pressure wave caused by calculation for release rate of chemical material, dispersion analysis, fire or explosion modeling through consequence analysis in priority, in this paper, we carry out calculation for release rate of pressured natural gas, radiant heat of fireball based in accident scenario of actual "San Bruno" buried high pressured pipelines through models which CCPS, TNO provide and compare with an actual damage result.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.11
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• pp.1368-1375
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• 2004

Measurements of OH chemiluminescence in an atmospheric pressure, laboratory-scale dump combustor at equivalence ratios ranging from 0.63 to 0.89 were reported. The signal from the first electronically excited state of OH to ground state was detected through a band-pass filter with an ICCD. The objectives of this study are two: One is to see the effects of equivalence ratio on global heat release rate and local Rayleigh index distribution. To get the local Rayleigh index distribution, the line-of-sight images were inverted by tomographic method, such as Abel do-convolution. Another aim is to investigate the validity of using OH chemiluminescence acquired with an ICCD as a qualitative measure of local heat release. For constant inlet velocity and temperature, the overall intensities of OH emission acquired at different equivalence ratio showed periodic and higher value at high equivalence ratio. OH intensity averaged over one period of pressure increased exponentially with equivalence ratio. Local Rayleigh index distribution clearly showed the region of amplifying or damping the combustion instability as equivalence ratio increased. It could provide an information/insights on active control such as secondary fuel injection. Finally, local heat release rate derived from reconstructed OH images were presented fur typical locations.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2792-2800
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• 2022

In the core of the WWR-K reactor, a long-term irradiation of tristructural isotopic (TRISO)-coated fuel particles (CFPs) with a UO₂ kernel was carried out under high-temperature gas-cooled reactor (HTGR)-like operating conditions. The temperature of this TRISO fuel during irradiation varied in the range of 950-1100 ℃. A fission per initial metal atom (FIMA) of uranium burnup of 9.9% was reached. The release of gaseous fission products was measured in-pile. The release-to-birth ratio (R/B) for the fission product isotopes was calculated. Aspects of fuel safety while achieving deep fuel burnup are important and relevant, including maintaining the integrity of the fuel coatings. The main mechanisms of fuel failure are kernel migration, silicon carbide corrosion by palladium, and gas pressure increase inside the CFP. The formation of gaseous fission products and carbon monoxide leads to an increase in the internal pressure in the CFP, which is a dominant failure mechanism of the coatings under this level of burnup. Irradiated fuel compacts were subjected to electric dissociation to isolate the CFPs from the fuel compacts. In addition, nondestructive methods, such as X-ray radiography and gamma spectrometry, were used. The predicted R/B ratio was evaluated using the fission gas release model developed in the high-temperature test reactor (HTTR) project. In the model, both the through-coatings of failed CFPs and as-fabricated uranium contamination were assumed to be sources of the fission gas. The obtained R/B ratio for gaseous fission products allows the finalization and validation of the model for the release of fission products from the CFPs and fuel compacts. The success of the integrity of TRISO fuel irradiated at approximately 9.9% FIMA was demonstrated. A low fuel failure fraction and R/B ratios indicated good performance and reliability of the studied TRISO fuel.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.214-221
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• 2012

In recent years, some researchers reported that myofascia was innervated by the autonomic nervous system. However, there is no neurophysiological explanation and evidence for the effects of myofascial release(MFR). Thus, the aim of this study was to determine whether the excitability of the autonomic nervous system is modulated by MFR. In this study, thirty healthy subjects in their 20s were randomly assigned to a myofascial release group(MG) and a placebo control group(PCG); each group had 15 subjects. The MG conducted 5 minutes of cranial base release in supine position, and the PCG performed sham cranial base release. Muscle flexibility was measured with the neck range of motion and the changes of the autonomic nervous system excitability was measured by heart rate, blood pressure, and concentration of plasma epinephrine and norepinephrine. The results were as follows: 1. The percentage changes in the cervical range of motion for extension and side flexion were significantly increased in the MG, signifying that more muscle relaxation. 2. There was no significant percentage changes in heart rate, blood pressure, and concentration plasma epinephrine between MG and PCG. 3. The percentage change in concentration plasma norepinephrine was significantly different between MG and PCG. The result of this study suggests that there is no evidence that MFR can modulate the autonomic nervous system excitability.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.524-529
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• 2007

Pressure inactivation behavior of Bacillus amyloliquefaciens spores was investigated in deionized water. The spores of B. amyloliquefaciens were subjected to $105^{\circ}C$ and 700 MPa. The magnitude of the decrease in viability after pressure treatment was similar to that after pressure treatment followed by heat shock. The increase of dipicolinic acid (DPA) release was correlated with the spore inactivation, and the hydrophobicity did not significantly change during the pressure-assisted thermal processing (PATP). Lag phase duration increased with increasing pressure process time. The mechanisms of spore germination and inactivation during the PATP were related to a complex physiological process.