• Progress in Medical Physics
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• v.25 no.4
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• pp.218-224
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• 2014

The small field dosimetry is very important in modern radiotherapy because it has been frequently used to treat the tumor with high dose hypo-fractionated radiotherapy or high dose single fraction stereotactic radiosurgery (SRS) with small size target. But, the dosimetry of a small field (< $3{\times}3cm^2$) has been great challenges in radiotherapy. Small field dosimetry is difficult because of (a) a lack of lateral electronic equilibrium, (b) steep dose gradients, and (c) partial blocking of the source. The objectives of this study were to measure and verify with the various detectors the output factors in a small field (<3 cm) for the 6 MV photon beams. Output factors were measured using the CC13, CC01, EDGE detector, thermoluminescence dosimeters (TLDs), and Gafchromic EBT2 films at the sizes of field such as $0.5{\times}0.5$, $1{\times}1$, $2{\times}2$, $3{\times}3$, $5{\times}5$, and $10{\times}10cm^2$. The differences in the output factors with the various detectors increased with decreasing field size. Our study demonstrates that the dosimetry for a small photon beam (< $3{\times}3cm^2$) should use CC01 or EDGE detectors with a small active volume. And also, Output factors with the EDGE detectors in a small field (< $3{\times}3cm^2$) coincided well with the Gafchromic EBT2 films.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.353-359
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• 2004

The extent of silica flocculation can be modified by varying the silica concentration, aqueous phase pH, salt and polvmer concentration. High volume fraction W/O emulsion stabilized by hydrophobic silica was established with various aqueous phase conditions for cosmetic application. By increasing the silica concentration up to $1.0\;wt\%,$ the size of droplet decreased. A high silica concentration increased the viscosity of continuous oil phase by network formation, which resulted in target size of droplet. The stability of W/O emulsion is improved as increasing the aqueous phase pH. At low and intermediate pH, the emulsions became more stable by adding salt $(0.083\;mol\;dm^{-3}\;MgSO_4).$ At high PH, the presence of salt caused significant destabilization. The gelation behavior of the emulsion indicates that the effect of salt on silica-stabilized emulsion is derived from an electrostatic attraction. The addition of xanthan gum in aqueous phase increased the mono-dispersity of the W/O emulsion by making water more hydrophobic and hindering the recombination of droplets. In conclusion, these results indicate that very stable emulsifier-free, finely dispersed W/O emulsion can be achieved for cosmetic application by changing the aqueous phase composition.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.491-496
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• 2006

Antimicrobial activity of 18 different traditional medicinal herbs extracts against Staphylococcus aureus was determined by a paper disc method. The Prunella vulgaris, Caesalpinia sappan and Rhus javanica extracts in 5 mg/ml, Poncirus trifoliata, Lonicera japonica and Seutellaria baicalensis extracts in 10 mg/ml and Schizandra chinensis, Alpinia katsumadai, Siegesbeckia orientalis extracts in 30 mg/ml showed a significant antimicrobial activity against Staphylococcus aureus. Minimum inhibitory concentrations of medicinal herbs extracts were in the range of $1{\sim}34\;mg/ml$ and $1{\sim}46\;mg/ml$, in the case of MeOH extracts and EtOH extracts, respectively. In addition, the antimicrobial activity of each solvent fraction was most significant with EtOAc layer. Optical density at 620nm after 24 hours incubation of Staphylococcus aureus in the presence of 100, 300 or 500 ppm of Caesalpinia sappan extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Caesalpinia sappan extract, indicating that growth of Staphylococcus aureus was significantly inhibited within 24 hours by the addition of at least 100 ppm of Caesalpinia sappan extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Rhus javanica extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Rhus javanica extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Rhus javanica extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Seutellaria baicalensis extract ranged from 0.02 to 0.07 compared to 0.4 in the absence of Seutellaria baicalensis extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Seutellaria baicalensis extract. In conclusion, these findings suggest that extracts from medicinal herbs may play important roles for antimicrobial activities against Staphylococcus aureus.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.233-243
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• 2009

We have investigated the infrared spectra for CO adsorbed on silica supported nickel(Ni-Si$O_2$), silica supported copper(Cu-Si$O_2$), silica supported nickel-copper alloys(Ni/Cu-Si$O_2$) of several compositions with varying CO pressures(0.2 $torr{\sim}$50 torr) at room temperature and on pumping to vacumn at room temperature within the frequency range of 1500 $cm^{-1}{\sim}2500\;cm^{-1}$. Four bands(2059.6 $cm^{-1},\;{\sim}$2036.5 $cm^{-1},\;{\sim}$ 1868.7 $cm^{-1},\;{\sim}$ 1697.1 $cm^{-1}$) were observed for Ni-Si$O_2$, two bands($\sim$2115.5 $cm^{-1},\;{\sim}$1743.0 $cm^{-1}$) were observed for Cu-Si$O_2$ and five bands(${\sim}2123.2\;cm^{-1}$, 2059.6 $cm^{-1},\;{\sim}$2036.4 $cm^{-1},\;{\sim}$1899.5 $cm^{-1},\;{\sim}$1697.1 $cm^{-1}$) were observed for Ni/Cu-Si$O_2$. These absorption bands correspond with those of the previous reports approximately. The bands below 1800 $cm^{-1}$ were only observed with Ni metal or Ni/Cu alloy crystal plane containing step at room temperature and the ${\sim}1697.1\;cm^{-1}$ bands observed with Ni-Si$O_2$ and Ni/Cu-Si$O_2$ may be ascribed to CO molecule adsorbed on the adsorption sites near step. The bands below 2000 $cm^{-1}$ were rarely observed with Cu metal crystal plane at room temperature and the 1743.0 $cm^{-1}$ bands may be ascribed to CO molecule adsorbed on the adsorption sites near step. The band shifts of adsorbed CO with varing Cu contents from 0 to 0.5 mole fraction at the same CO pressure or at the same pumping time to vacumn were below 21 $cm^{-1}$. and comparatively small than those with other ⅠB metal addition. It may means ligand effect of Cu d electron is small.

• Tuberculosis and Respiratory Diseases
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• v.44 no.6
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• pp.1326-1331
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• 1997

Background : Weaning is the process of switching a patient from mechanical ventilator to spontaneous breathing. A number of different weaning techniques can be employed. At recent study, conventional spontaneous breathing trial was superior to other techniques, such as intermittent mandatory ventilation(IMV) or pressure support ventilation(PSV). But adequate observation time of the spontaneous breathing trial was not determined. We reported the effectiveness of weaning and extubation following a 60 minutes spontaneous breathing trial with simple oxygen supply through the endotrachial tube. In this study, we tried to shorten the spontaneous breathing time from 60 minutes to 30 minutes. If weaning success was predicted after 30 minutes spontaneous breathing, extubation was done without reconnection with ventilator. Methodes : Subjects consisted of 42 mechanically ventilated patients from August 1994 to July 1995. The weaning trial was done when the patients recovered sufficiently from respiratory failure that originally required ventilatory assistance, the patients became alert and showed stable vital sign, and arterial $O_2$ tension was adequated($PaO_2$ > 55 mmHg) with less than 40% of inspired oxygen fraction. We conducted a careful physical examination when the patients was breathing spontaneously through the endobronchial tube for 30 minutes. We terminated the trial if a patients was any of following signs of distress; cyanosis, diaphoresis, tachypnea(above 30 breaths per minute), and extreme tachycardia. Patients who had none of this features during spontaneous breathing for 30 minutes were extubated promptly. Result : 17 weaning trials of 15 patients were done in 42 mechanically ventilated patients. Successful weaning and extubation was possible in 14 trials of total 17 trials. In this 14 patients, 8 patients were extubated after 30 minutes spontaneous breathing, 3 patients were extubated after 60 minutes spontaneous breathing, and 3 patients needed over 3 hours for extubation from weaning. We found similar overall success rate compared with weaning following a 60 minutes spontaneous breathing trial. Conclusion : From the result of present study, we believe that weaning and extubation from mechanical ventilation following a 30 minutes spontaneous breathing with $O_2$ supply through the endotracheal tube is a simple and effective method.

• Tuberculosis and Respiratory Diseases
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• v.60 no.6
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• pp.625-630
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• 2006

Background: Pulmonary hypertension in COPD patients is the result of a direct effect of tobacco smoke on the intrapulmonary vessels with the abnormal production of the mediators that control vasoconstriction, vasodilatation, and vascular cell proliferation, which ultimately lead to aberrant vascular remodeling and physiology. COPD patients are prone to the developmint of an acute and chronic thromboembolism with an elevation of the plasma procoagulant and fibrinolytic markers However, the roles of the coagulation and fibrinolysis system on the right ventricular dysfunction in COPD patients are not well defined. We examined the alteration of the coagulation and fibrinolysis system in COPD patients according to the right ventricular function measured using cardiac multidetector computed tomography (MDCT). Methods: The right ventricular ejection fraction (RVEF) was measured using cardiac MDCT in 26 patients who were diagnosed with COPD according to the definition of the GOLD guideline. The plasma level of thrombin antithrombin (TAT) and plasminogen activator inhibitor (PAI)-1 were measured using an enzyme linked immunoassay. Results: The plasma TAT was markedly elevated in COPD patients ($10.5{\pm}19.8{\mu}g/L$) compared with those of the control ($3.4{\pm}2.5{\mu}g/L$) (p<0.01). However, the plasma PAI-1 in COPD patients ($29.6{\pm}20.7ng/mL$) was similar to that in the controls. The plasma TAT showed a significant inverse relationship with the RVEF measured by the cardiac MDCT in COPD patients (r=-0.645, p<0.01). However, the plasma PAI-1 did not show a relationship with the RVEF (r=0.022, p=0.92). Conclusion: These results suggest that the coagulation system in COPD patients is markedly activated, and that the plasma level of TAT might be a marker of a right ventricular dysfunction in COPD patients.

• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.1-16
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• 1993

As guides to decision-making in the management of the victims in case of acute whole body or partial body radiation exposure, we studied the relationship between radiation dose and the frequency of chromosomal aberrations observed in peripheral lymphocytes that were irradiated in vitro with $^{60}Co\;{\gamma}-rays$ at doses ranging from 2Gy to 12Gy. The yields of cells with unstable chromosomal aberrations (dicentric chromosomes, ring chromosomes, and acentric fragment pairs) were 32% at 2Gy, 47% at 4Gy, 80% at 6Gy, 94% at 8Gy, and 100% at 10Gy and over. Ydr, which reflect average dose to the whole body in case of acute whole body exposure, were 1.373 at 2Gy, 0.669 at 4Gy, 1.734 at 6Gy, 2.773 at 8Gy, 3.746 at 10Gy and 5.454 at 12Gy. The relationship between radiation dose (D) and the frequency of dicentric plus ring chromosomes per cell(Ydr) could be expressed as $Ydr=9.322{\times}10^{-2}/Gy {\times}D+2.975{\times}10^{-2}/Gy^2{\times}D^2$. Qdr, which are used in estimating dose of partial body exposure and dose of past exposure, were 1.166 at 2Gy, 1.436 at 4Gy, 2.173 at 6Gy, 2.945 at 8Gy, 3.746 at 10Gy and 5.454 at 12Gy. To see how confidently this dosimetry system may be used, we obtained Qdr values from those who received one fraction of homogenous partial body irradiation of 1.BGy, 2.5Gy, and 7.OGy therapeutically; in vivo Qdr values were 1.109, 1.222 and 2.222 respectively. The estimated doses calculated from these in vivo Qdr values using the equation $Qdr=Ydr/(1- e^{-Ydr})$ were 1.52Gy, 2.48Gy, and 6.54Gy respectively, which were very close to the doses actually given.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.7-14
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• 2006

Entomopathogenic fungus Cordyceps militaris is famous for its medicinal efficacies. It has been reported to have various pharmacological activities such as anti-tumour, insecticidal, antibacterial, immunomodulatory and antioxidant. In this study, we investigated the effect of the extract of C. militaris (MPUN8501), which was identified by the analysis of the nucleotide sequences of 5.8S ribosomal RNA, on the function of liver. C. militaris powder was extracted using hot water extracts method as time, volume and temperature and using method as differential polarity of organic solvent. Each fraction was tested for the improvement of hepatic enzyme alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activity. The BuOH extracts (CME) had highest activity which was used for the test of toxicity and efficacy of C. militaris. The enhancing effect of CME on the activity of ADH and ALDH was much more than medicine, drink, natural tea etc. Thus CME promoted the resolution of alcohol and acetaldehyde in rats, inducing recovery to normal condition rapidly. Furthermore, oral administration of CME effectively protected the carbon tetrachloride-induced acute hepatic injury as revealed by the hematological parameters (levels of sGOT and sGPT) and histological observation. CME was ascertained to be safe by regulatory toxicity studies of single dose toxicity and genotoxicity. These results suggest that CME would be useful for the maintaining normal hepatic activity as a functional health food.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.47-54
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• 1988

Cholesterol a component of all eucaryotic plasma membranes. is essential for the growth and viability of cells in higher organisms. However. too much cholesterol can be lethal because of atherosclerosis resulting from the deposition of cholesterol ester plaques. It was attempted in this study to understand the preventive effect of ginseng saponin. one of the major components of the roots of Panax ginseng C.A. Meyer. against hypercholesterolemia induced by high cholesterol diet. $^{125}I-LDL$ was injected intravenously to rabbits and rats. which were fed a high cholesterol diet with and/or without ginseng saponin for 12 days. The disappearance of the radioactivity occurred faster in the test group than the control. The effect of saponin fraction from Panax ginseng C.A. Meyer and the purified ginsenosilks. $Rb_1,\;Rb_2,\;Re\;and\;Rg_1,$ on LDL receptor biosynthesis in high cholesterol fed rat has been investigated. Analysis of LDL receptors from various organs such as liver. kidney. adrenal cortex and testis showed that the population of LDL receptors of test group significantly higher than that of the control. It was also found that liver homogenate containing ginsenosides $(10^{-3}-10^{-4}\%)$ stimulated the biosynthesis of bile acid form cholesterol. From the above results. it seemed that ginsenosides lower the cholesterol level by stimulating cholesterol metabolism. which result in the suppression of the inhibitory action of cholesterol on LDL receptor biosynthesis.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.384-391
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• 2019

Nutrients in stormwater runoff have raised concerns regarding water quality degradation in the recent years. Low impact development (LID) technologies are types of nature-based solutions developed to address water quality problems and restore the predevelopment hydrology of a catchment area. Two LID facilities, infiltration trench (IT) and infiltration planter (IP), are known for their high removal rate of nutrients through sedimentation and vegetation. Long-term monitoring was conducted to assess the performance and cite the advantages and disadvantages of utilizing the facilities in nutrient removal. Since a strong ionic bond exists between phosphorus compounds and sediments, reduction of total phosphorus (TP) (more than 76%), in both facilities was associated to the removal of total suspended solids (TSS) (more than 84%). The efficiency of nitrogen in IP is 28% higher than IT. Effective nitrification occurred in IT and particulate forms of nitrogen were removed through sedimentation and media filters. Decrease in ammonium- nitrogen (NH₄-N) and nitrite-nitrogen (NO₂-N), and increase in nitrate-nitrogen (NO₃-N) fraction forms indicated that effective nitrification and denitrification occurred in IP. Hydrologic factors such as rainfall depth and rainfall intensity affected nutrient treatment capabilities of urban stormwater LID facilities The greatest monitored rainfall intensity of 11 mm/hr for IT yielded to 34% and 55% removal efficiencies for TN and TP, respectively, whereas, low rainfall intensities below 5 mm resulted to 100 % removal efficiency. The greatest monitored rainfall intensity for IP was 27 mm/hr, which still resulted to high removal efficiencies of 98% and 97% for TN and TP, respectively. Water quality assessment showed that both facilities were effective in reducing the amount of nutrients; however, IP was found to be more efficient than IT due to its additional provisions for plant uptake and larger storage volume.