• Journal of IKEEE
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• v.28 no.1
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• pp.97-103
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• 2024

Some drugs can offer far better medical effectiveness as it is injected through the intradermal layer of the skin, known as a needle-free injection. However, conventional needle-free devices might deliver a relatively large amount of drug in a just single spot of skin, splitting open the tissue layer structure, which might cause bruising and bleeding. By injecting the small volume with a fast repetition rate in a large surface area of skin, the patient may get much fewer injuries and pain. To achieve that specification, the driving force must be instantaneous and short-pulsed. Such a form of an injection device has been developed but the efficacy of those devices has been rarely examined. Therefore, this study developed the laser-induced microjet device that ejects microjet whose speed is ~310 m/s, during the 400~800 ㎲ of pulse time. The device can eject ~1 µL of the drug at the rate at which each shot repeated 10 shots per second. Using this specification, we evaluated the efficacy of drug injection onto mouse models. After injecting the insulin solution into the mouse model, the blood insulin level is detected, resulting in 20 % of blood insulin level with the ordinary needle syringe injection method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.271-279
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• 1984

Effects of temperature and additives on the stability of actomyosin extracted from skeletal muscle of Israeli carp, Cyprinus carpio nudus, were studied by analyzing free SH-group, ATP-sensitivity and Ca-ATPase activity. The used additives were sucrose, sorbitol, Na-glutamate and L-cysteine. Furthermore, the denaturation constant($K_D$), protective effect(${\Delta}E/M$) and the other thermo-dynamic parameters on protein denaturation are systematically discussed. The actomyosin showed $4.12{\sim}4.68 mg/ml$ in protein concentration, $2.63{\sim}2.93\%$ in ribonucleic acid to the protein, $1:2.20{\sim}2.63$ in the binding ratio of myosin and actin, $4.33{\sim}5.26\%$ in fat content, 109.78 in ATP-sonsitivity, $0.159{\sim}0.201\;{\mu}M-Pi/min/mg-protein$ in Ca-ATPase activity and $3.3{\sim}3.4M/10^5$g-protein in free SH-group content. The first-order rate plots were obtained on the decrease of Ca-ATPase activity and ATP-sensitivity with an increase in temperature, while the free SH-group was increased to $60^{\circ}C$ and decreased rapidly above the temperature. The half-life of Ca-ATPase activity on the actomyosin Ca-ATPase was 280 min at $12^{\circ}C$, 125 min at $20^{\circ}C$, 55 min at $30^{\circ}C$ and 13 min at $40^{\circ}C$, and activation energy, activation enthalpy, activation entropy and free energy of the proteins at $20^{\circ}C$ wene 5,395 cal/mole, 4,814 cal/mole, -40.42 e.u. and 17,626 cal/mole, respectively. The protective effect of the additives on the actomyosin Ca-ATPase showed that the most effective material is $3\%$ sorbitol and followed in the order of $8\%$ Na-glutamate, $1\%$ sucrose and $1\%$ L-cysteine. The actomyosin was more stable at $-30^{\circ}C$ than at $0^{\circ}C$ and $-20^{\circ}C$. and when the additives were used in the low temperature storage, $8\%$ Na-glutamate was the most effective. $3\%$ sorbitol, $1\%$ sucrose and $1\%$ L-cysteine was to become lower in the order.

• Journal of Astronomy and Space Sciences
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• v.22 no.2
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• pp.147-174
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• 2005

To understand the physical processes that control the high-latitude lower thermospheric dynamics, we quantify the forces that are mainly responsible for maintaining the high-latitude lower thermospheric wind system with the aid of the National Center for Atmospheric Research Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEGCM). Momentum forcing is statistically analyzed in magnetic coordinates, and its behavior with respect to the magnitude and orientation of the interplanetary magnetic field (IMF) is further examined. By subtracting the values with zero IMF from those with non-zero IMF, we obtained the difference winds and forces in the high-latitude 1ower thermosphere(<180 km). They show a simple structure over the polar cap and auroral regions for positive($B_y$ > 0.8|$\overline{B}_z$ |) or negative($B_y$ < -0.8|$\overline{B}_z$|) IMF-$\overline{B}_y$ conditions, with maximum values appearing around -80$^{\circ}$ magnetic latitude. Difference winds and difference forces for negative and positive $\overline{B}_y$ have an opposite sign and similar strength each other. For positive($B_z$ > 0.3125|$\overline{B}_y$|) or negative($B_z$ < -0.3125|$\overline{B}_y$|) IMF-$\overline{B}_z$ conditions the difference winds and difference forces are noted to subauroral latitudes. Difference winds and difference forces for negative $\overline{B}_z$ have an opposite sign to positive $\overline{B}_z$ condition. Those for negative $\overline{B}_z$ are stronger than those for positive indicating that negative $\overline{B}_z$ has a stronger effect on the winds and momentum forces than does positive $\overline{B}_z$ At higher altitudes(>125 km) the primary forces that determine the variations of tile neutral winds are the pressure gradient, Coriolis and rotational Pedersen ion drag forces; however, at various locations and times significant contributions can be made by the horizontal advection force. On the other hand, at lower altitudes(108-125 km) the pressure gradient, Coriolis and non-rotational Hall ion drag forces determine the variations of the neutral winds. At lower altitudes(<108 km) it tends to generate a geostrophic motion with the balance between the pressure gradient and Coriolis forces. The northward component of IMF By-dependent average momentum forces act more significantly on the neutral motion except for the ion drag. At lower altitudes(108-425 km) for negative IMF-$\overline{B}_y$ condition the ion drag force tends to generate a warm clockwise circulation with downward vertical motion associated with the adiabatic compress heating in the polar cap region. For positive IMF-$\overline{B}_y$ condition it tends to generate a cold anticlockwise circulation with upward vertical motion associated with the adiabatic expansion cooling in the polar cap region. For negative IMF-$\overline{B}_z$ the ion drag force tends to generate a cold anticlockwise circulation with upward vertical motion in the dawn sector. For positive IMF-$\overline{B}_z$ it tends to generate a warm clockwise circulation with downward vertical motion in the dawn sector.

• Korean Journal of Ecology and Environment
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• v.34 no.1 s.93
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• pp.9-19
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• 2001

contrasting monsoon between 1993 and 1994 produced an interannual difference in hydrology. Theoretical water residence time (TWRT) in monsoon 1993 averaged 27 d, which was>3 months shorter compared to the TWRT in monsoon 1994. A dominant physical process influencing thermal stratification, water movement, and mixing regime was an interflow current in 1993. During summer 1993, river water plunged to mid-lake (location 27 km) and passed through the 10${\sim}$20m stratum of the reservoir, resulting in an isolation of epilimnetic lake water from advected river water. The interflow disrupted thermal stratification and produced a meta-hypolimnetic warming of >4$^{\circ}C$ downlake, thereby increased a mixing depth (>13 m). In contrast, during monsoon 1994 density currents were not observed and strong thermal stratification occurred in the entire reservoir, resulting in > 2 fold greater thermal resistance (8.2${\times}10^{5}$ erg)compared to 1993 (4.0${\times}10^{5}$ erg). This reservoir was identified as a typical warm monomictic reservoir which showed one mixis during early winter. The timing of overturn, however, differed between the two years as a result of distinct contrast in TWRT and thermal regime; overturn in 1993 occured about one month earlier relative to that in 1994. Hypolimnetic warming was predictable in this system; the variation in discharge accounted (Y = 4.35-0.06X+0.10X$^{2}$, p<0.0001)for 98% of the interannual variation in hypolimnetic temperature. Overall data suggest that thermal stability, the timing of fall overturn, and water residence time in this system are primarily regulated by the intensity of monsoon.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.576-582
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• 2003

During the Off-Pump Coronary Arterial Bypass surgery (OPCAB), the manipulation of the heart can depress cardiac contractility and cause hemodynamic instability. In this study, hemodynamic parameters were measured during operation and the laboratory and clinical data were investigated to evaluate their effects on postoperative outcome. Material and Method: From March 2001 to August 2002, 50 consecutive patients who underwent OPCAB were included in this study. During the same period, total number of CABG was 71 The blood pressure, pulmonary artery pressure, mixed venous oxygen saturation, and cardiac index were measured before manipulation, after application of stabilizer, and at the end of anastomosis. Postoperatively, we measured the cardiac enzymes such as CK-MB, troponin 1 and checked the amount of inotropes required, chest tube drainage, the amount of transfusion, duration of ventilator support, and duration of ICU stay. Result: The number of mean distal anastomoses was 2.8$\pm$0.9 per patient. On elevation and stabilization of the heart, systolic blood pressure was depressed and pulmonary artery pressure was elevated significantly, but during each anastomosis no significant changes were detected. The peak level of cardiac markers was 29.2$\pm$46.7 for CK-MB, 0.69$\pm$0.86 for troponin 1 on postoperative day f. Among the intraoperative hemodynamic parameters, the ischemic change of EKG and bolus injection of inotropes significantly affected the posteroperative cardiac enzymes. But, no difference other than the level of cardiac enzymes between the two groups with or without the ischemic change of EKG and bolus injection of inotropes was noticed. Conclusion: The significant hemodynamic changes occurred when the heart was elevated and stabilized, however during anastomoses there were no significant changes. Serum cardiac enzymes rose significantly in the group that showed the ischemic charge of EKG or needed the bolus injection of inotropes for maintaining hemodynamic stability intraoperatively, but it did not affect the postoperative outcome. In conclusion, the ischemic change of EKG and the need for bolus injection of intropes during operation may be very indicative for probable ischemia.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.531-542
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• 2021

Open-pit mines require constant monitoring as they can cause surface changes and environmental disturbances. In open-pit mines, there is little vegetation at the mining site and can be monitored using InSAR (Interferometric Synthetic Aperture Radar) coherence imageries. In this study, activities occurring in mine were analyzed by applying the recently developed InSAR coherence-based NDAI (Normalized Difference Activity Index). The March 5 Youth Mine is a North Korean mine whose development has been expanded since 2008. NDAI analysis was performed with InSAR coherence imageries obtained using Sentinel-1 SAR images taken at 12-day intervals in the March 5 Youth Mine. First, the area where the elevation decreased by about 75.24 m and increased by about 9.85 m over the 14 years from 2000 was defined as the mining site and the tailings piles. Then, the NDAI images were used for time series analysis at various time intervals. Over the entire period (2017-2019), average mining activity was relatively active at the center of the mining area. In order to find out more detailed changes in the surface activity of the mine, the time interval was reduced and the activity was observed over a 1-year period. In 2017, we analyzed changes in mining operations before and after artificial earthquakes based on seismic data and NDAI images. After the large-scale blasting that occurred on 30 April 2017, activity was detected west of the mining area. It is estimated that the size of the mining area was enlarged by two blasts on 30 September 2017. The time-averaged NDAI images used to perform detailed time-series analysis were generated over a period of 1 year and 4 months, and then composited into RGB images. Annual analysis of activity confirmed an active region in the northeast of the mining area in 2018 and found the characteristic activity of the expansion of tailings piles in 2019. Time series analysis using NDAI was able to detect random surface changes in open-pit mines that are difficult to identify with optical images. Especially in areas where in situ data is not available, remote sensing can effectively perform mining activity analysis.

• Tuberculosis and Respiratory Diseases
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• v.40 no.2
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• pp.135-146
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• 1993

Background: In acute pulmonary embolism it has been postulated that the constriction of bronchi and pulmonary artery secondary to neurohumoral response plays an important role in cardiopulmonary dysfunction in addition to the mechanical obstruction of pulmonary artery. Serotonin is considered as the most important mediator. Positive end expiratory pressure (PEEP) stimulates $PGI_2$ secretion from the vascular endothelium, but its role in acute pulmonary embolism is still in controversy. Methods: To study the cardiopulmonary effect and therapeutic role of Ketanserin, selective antagonist of 5-HT2 receptor, and PEEP in acute pulmonary embolism experimental acute pulmonary embolism was induced in dogs with autologous blood clot. The experimental animals were divided into 3 groups, that is control group, Ketanserin injection group and PEEP application group. Results: Thirty minutes after embolization, mean pulmonary arterial pressure and pulmonary vascular resistance increased and cardiac output decreased. $PaO_2,\;P\bar{v}O_2$ and oxygen transport decreased and physiological shunt and $PaCO_2$ increased. After injection of Ketanserin, comparing with control group, mean pulmonary arterial pressure, pulmonary vascular resistance and physiological shunt decreased, while cardiac output, $PaO_2$ and oxygen transport increased. All these changes sustained till 4 hours after embolization. After PEEP application pulmonary vascular resistance, $PaO_2$ and $PaCO_2$ increased, while physiological shunt, cardiac output and oxygen transport decreased. After discontinuation of PEEP, mean pulmonary arterial pressure and pulmonary vascular resistance decreased and were lower than control group, while $PaO_2$ and cardiac output increased and higher than control group. $PaCO_2$ decreased but showed no significant difference comparing with control group. Conclusion: It can be concluded that Ketanserin is effective for the treatment of acute pulmonary embolism. With PEEP hemodynamic status deteriorated, but improved better than control group after discontinuation of PEEP. Thus PEEP may be applied carefully for short period in acute pulmonary embolism if the hemodynamic status is tolerable.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.65-72
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• 2008

The purpose of the HLW deep geological disposal is to isolate and to delay the radioactive material release to human beings and the environment for a long time so that the toxicity does not affect to the environment. The main requirements for the HLW repository design is to keep the buffer temperature below $100\;^{\circ}C$ in order to maintain its integrity. So the cooling time of spent fuels discharged from the nuclear power plant is the key consideration factors for efficiency and economic feasibility of the repository. The disposal tunnel/disposal hole spacing, the disposal area and thermal capacity required for the deep geological repository layout which satisfies the temperature requirement of the disposal system is analyzed to set the optimized spent fuels cooling time. To do this, based on the reference disposal concept, thermal stability analyses of the disposal system have been performed and the derived results have been compared by setting the spent fuels cooling time and the disposal tunnel/disposal hole spacing in various ways. From these results, desirable spent fuels cooling time in view of disposal area is derived. The results shows that the time reaching the maximum temperature within the design limit of the temperature in the disposal site is likely shortened as the cooling time of spent fuels becomes short. Also it seems that the temperature-rising and-dropping patterns in the disposal site are of smoothly varying form as the cooling time of spent fuels becomes long. In addition, it is revealed that a desirable cooling time of spent fuels is approximately 40-50 years when spent fuels are supposedly disposed in the deep geological disposal site with its structural scale under consideration in this study.

• Journal of the Korean earth science society
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• v.37 no.7
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• pp.448-464
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• 2016

The purpose of this study is to optimize the parameters related to consensus coherency within the PCL 1300, the operating program of wind profiler, from a validation of wind data between rawinsonde and wind profiler at Chupungryeong ($36^{\circ}13^{\prime}$, $127^{\circ}59^{\prime}$) site in Korea. It is then to analyze the diurnal and seasonal characteristics of the turbulence energy dissipation rate (${\varepsilon}$) in clear and rainy days from March 2009 to February 2010. In comparison of the wind data between wind profiler and rawinsonde during April 22-23, 2010, it was shown in a big error more than $10ms^{-1}$ over the height of 3,000 meters in the zonal (u) and meridional (v) wind components. When removing more than $10ms^{-1}$ in each wind speed difference of u an v components between the two instruments, the correlation coefficients of these wind components were 0.92 and 0.88, respectively, and the root mean square errors were 3.07 and $1.06ms^{-1}$. Based on these results, when the data processing time and the minimum available data within the PCL 1300 program were adjusted as 30 minutes and 60%, respectively, the bias errors were small. In addition, as a result of an analysis of sensitivity to consensus coherency of u and v components within the PCL1300 program, u components were underestimated in radial coherency, instantaneous and winbarbs coherency, whereas v components were overestimated. Finally by optimizing parameters of the PCL1300 program, the diurnal and seasonal means of ${\varepsilon}$ at each height were higher in rainy days than those in clear days because of increasing in the vertical wind speed due to upward and downward motions. The mean ${\varepsilon}$ for clear and rainy days in winter was lower than those of other seasons, due to stronger horizontal wind speed in winter than those in other seasons. Consequently, when the turbulence energy dissipation rates in the vertical wind speed of more than ${\pm}10cm\;s^{-1}$ were excluded for clear and rainy days, the mean ${\varepsilon}$ in rainy days was 6-7 times higher than that in clear days, but when considering them, it was 4-5 times higher.

• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.49-61
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• 1985

In view of the facts that dopamine (DA) when given directly into a lateral ventricle (i.c.v.) of the rabbit brain induces antidiuresis and that haloperidol, a non-specific antagonist of DA receptors, produces anti-diuresis in smaller doses and diuresis and natriuresis in larger doses, the present study was undertaken to delineate the roles of various DA receptors involved in the center-mediated regulation of renal function. Bromocriptine (BRC), a relatively specific agonist of D-2 receptors and at the same time a D-,1 antagonist, elicited natriuresis and diuresis when given i.c.v. in doses ranging from 20 to 600 {\mu}g/kg$, roughly in dose-related fashion, while the renal perfusion and glomerular filtration progressively decreased with doses, indicating that the diuretic, natriuretic action resides in the tubules, not related to the hemodynamic effects. These diuresis and natriuresis were most marked with 200 ${\mu}g/kg$, with the fractional sodium excretion reaching about 10%. With 600 ${\mu}g/kg$, however, the diuretic, natriuretic action was preceded by a transient oliguria resulting from severe reduction of renal perfusion, concomitant with marked but transient hypertension. When given intravenously, however, BRC produced antidiuresis and antinatriuresis along with decreases in renal hemodynamics associated with systemic hypotension, thus indicating that the renal effects produced by i.c.v. BRC is not caused by a direct renal effects of the agent which might have reached the systemic circulation. In experiments in which DA was given i.c.v. prior to BRC, 150 ${\mu}g/kg$ DA did not affect the effects of BRC (200 ${\mu}g/kg$), while 500 ${\mu}g/kg$ DA abolished the BRC effect. In rabbits treated with reserpine, 1 mg/kg i.v.,24 h prior to the experiment, i.c.v. BRC could unfold its renal effects not only undiminished but rather exaggerated and more promptly. In preparations in which one kidney is deprived of nervous connection, the denervated kidney responded with marked diuresis and natriuresis, whereas the innervated, control kidney exhibited antidiuresis. These observations suggest that i.c.v. BRC influences the renal function through release of some humoral natriuretic factor as well as by increasing sympathetic tone, and that various DA receptors might be involved with differential roles in the center-mediated regulation of the renal function.