• The Korean Journal of Physiology
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• v.19 no.2
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• pp.203-213
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• 1985

This study was carried out to investigate whether the K-pNPPase activity in renal cortical slices can be used as an index for measuring the activity of $Na^+-K^+$ exchange pump. The K-pNPPase activity, Ouabain-sensitive oxygen consumption add intracellular electrolytes content in slices, and Na-K-ATPase activity in microsome were measured and the effects of ouabain and vanadate on these were observed. The results are as follows : 1) p-NPPase activity in slices increased linearly with incubation time during 60 minutes, and $K^+$-dependent, ouabain-sensitive fraction was about 55% of total p-NPPase activity. This value was almost the same through out the incubation time. 2) The concentrations of ouabain and vanadate for 50f inhibition of K-pNPPase activity were$7.0{\times}10^{-6}M$ and $1.3{\times}10^{-5}M$, respectively. 3) The ouabain-sensitive oxygen consumption in slices was reduced to 50% of control value by $6.3{\times}10^{-6}M$ ouabain or $2.5{\times}10^{-5}M$ vanadate. These concentrations were similar to those for 50% inhibition of K-pNPPase activity. 4) The trends of intracellular electrolytes change by ouabain and vanadate were similar to those of the change in K-pNPPase activity. 5) The Na-K-ATPase activity in microsome prepared from renal cortex was completely inhibited by $10^{-3}M$ ouabain or $10^{-3}M$ vanadate and the concentration for 50% inhibition was $1.2{\times}10^{-6}M$ in ouabain and $1.6{\times}10^{-6}M$ in vanadate, which were much lower than those for K-pNPPase activity or ouabain-sensitive oxygen consumption in slices. These results indicate that K-pNPPase activity measured in renal cortical slices is a better index for evaluating $Na^+-K^+$ exchange pump activity than Na-K-ATPase activity measured in microsome.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.715-732
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• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Journal of The Korean Ophthalmological Society
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• v.59 no.11
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• pp.1017-1023
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• 2018

Purpose: A recently introduced phacoemulsification system, the WhiteStar $Signature^{(R)}$ PRO, has demonstrated improved nucleus followability and cutting efficiency via an improved pump regulator with a higher reaction response and an automatic occlusion sensing system. In this study, we compared various phacoemulsification parameters between the new system and an older version of the device. Methods: A total of 80 eyes of 68 patients with cataracts who had undergone phacoemulsification by a single surgeon were included in this study. Forty eyes of patients underwent phacoemulsification using the older $Signature^{(R)}$ system (WhiteStar); these patients were classified as the control group. Another 40 eyes of patients underwent phacoemulsification with the newer enhanced system, the WhiteStar $Signature^{(R)}$ PRO; these patients were assigned to the experimental group. During the operation, operative parameters, including the effective phaco time (parameter of effective phaco time with a specific coefficient for the transversal movement expressed in seconds, EFX), ultrasound time (seconds [s]), effective phacoemulsification time (EPT, s), average phacoemulsification power (AVG, %), and balanced salt solution usage, were measured to determine the performance enhancement offered by the updated system. Central corneal thickness was measured before and after surgery to compare corneal edema. The relationships between the two groups were analyzed using an independent t-test. Results: The Signature $PRO^{(R)}$ system showed a lower EFX (p < 0.001), a shorter EPT (p < 0.001), and a smaller AVG (p < 0.001). Postoperative corneal thickness did not differ significantly between the two groups. Conclusions: Comparing the efficacy of the improved reaction speed of the device and automatic occlusion sensing system in performing phacoemulsification, the updated Signature $PRO^{(R)}$ system demonstrated superior followability and cutting efficiency regardless of nuclear cataract hardness.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.215-235
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• 1996

The thermal analysis by mathematical model simulation makes it possible to reasonably predict heating and/or cooling requirements of certain greenhouses located under various geographical and climatic environment. It is another advantages of model simulation technique to be able to make it possible to select appropriate heating system, to set up energy utilization strategy, to schedule seasonal crop pattern, as well as to determine new greenhouse ranges. In this study, the control pattern for greenhouse microclimate is categorized as cooling and heating. Dynamic model was adopted to simulate heating requirements and/or energy conservation effectiveness such as energy saving by night-time thermal curtain, estimation of Heating Degree-Hours(HDH), long time prediction of greenhouse thermal behavior, etc. On the other hand, the cooling effects of ventilation, shading, and pad ||||&|||| fan system were partly analyzed by static model. By the experimental work with small size model greenhouse of 1.2m$\times$2.4m, it was found that cooling the greenhouse by spraying cold water directly on greenhouse cover surface or by recirculating cold water through heat exchangers would be effective in greenhouse summer cooling. The mathematical model developed for greenhouse model simulation is highly applicable because it can reflects various climatic factors like temperature, humidity, beam and diffuse solar radiation, wind velocity, etc. This model was closely verified by various weather data obtained through long period greenhouse experiment. Most of the materials relating with greenhouse heating or cooling components were obtained from model greenhouse simulated mathematically by using typical year(1987) data of Jinju Gyeongnam. But some of the materials relating with greenhouse cooling was obtained by performing model experiments which include analyzing cooling effect of water sprayed directly on greenhouse roof surface. The results are summarized as follows : 1. The heating requirements of model greenhouse were highly related with the minimum temperature set for given greenhouse. The setting temperature at night-time is much more influential on heating energy requirement than that at day-time. Therefore It is highly recommended that night- time setting temperature should be carefully determined and controlled. 2. The HDH data obtained by conventional method were estimated on the basis of considerably long term average weather temperature together with the standard base temperature(usually 18.3$^{\circ}C$). This kind of data can merely be used as a relative comparison criteria about heating load, but is not applicable in the calculation of greenhouse heating requirements because of the limited consideration of climatic factors and inappropriate base temperature. By comparing the HDM data with the results of simulation, it is found that the heating system design by HDH data will probably overshoot the actual heating requirement. 3. The energy saving effect of night-time thermal curtain as well as estimated heating requirement is found to be sensitively related with weather condition: Thermal curtain adopted for simulation showed high effectiveness in energy saving which amounts to more than 50% of annual heating requirement. 4. The ventilation performances doting warm seasons are mainly influenced by air exchange rate even though there are some variations depending on greenhouse structural difference, weather and cropping conditions. For air exchanges above 1 volume per minute, the reduction rate of temperature rise on both types of considered greenhouse becomes modest with the additional increase of ventilation capacity. Therefore the desirable ventilation capacity is assumed to be 1 air change per minute, which is the recommended ventilation rate in common greenhouse. 5. In glass covered greenhouse with full production, under clear weather of 50% RH, and continuous 1 air change per minute, the temperature drop in 50% shaded greenhouse and pad ＆ fan systemed greenhouse is 2.6$^{\circ}C$ and.6.1$^{\circ}C$ respectively. The temperature in control greenhouse under continuous air change at this time was 36.6$^{\circ}C$ which was 5.3$^{\circ}C$ above ambient temperature. As a result the greenhouse temperature can be maintained 3$^{\circ}C$ below ambient temperature. But when RH is 80%, it was impossible to drop greenhouse temperature below ambient temperature because possible temperature reduction by pad ||||&|||| fan system at this time is not more than 2.4$^{\circ}C$. 6. During 3 months of hot summer season if the greenhouse is assumed to be cooled only when greenhouse temperature rise above 27$^{\circ}C$, the relationship between RH of ambient air and greenhouse temperature drop($\Delta$T) was formulated as follows : $\Delta$T= -0.077RH＋7.7 7. Time dependent cooling effects performed by operation of each or combination of ventilation, 50% shading, pad ＆ fan of 80% efficiency, were continuously predicted for one typical summer day long. When the greenhouse was cooled only by 1 air change per minute, greenhouse air temperature was 5$^{\circ}C$ above outdoor temperature. Either method alone can not drop greenhouse air temperature below outdoor temperature even under the fully cropped situations. But when both systems were operated together, greenhouse air temperature can be controlled to about 2.0-2.3$^{\circ}C$ below ambient temperature. 8. When the cool water of 6.5-8.5$^{\circ}C$ was sprayed on greenhouse roof surface with the water flow rate of 1.3 liter/min per unit greenhouse floor area, greenhouse air temperature could be dropped down to 16.5-18.$0^{\circ}C$, whlch is about 1$0^{\circ}C$ below the ambient temperature of 26.5-28.$0^{\circ}C$ at that time. The most important thing in cooling greenhouse air effectively with water spray may be obtaining plenty of cool water source like ground water itself or cold water produced by heat-pump. Future work is focused on not only analyzing the feasibility of heat pump operation but also finding the relationships between greenhouse air temperature(T$_{g}$ ), spraying water temperature(T$_{w}$ ), water flow rate(Q), and ambient temperature(T$_{o}$).

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.159-164
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• 2014

The objective of this study was to establish an open-field experimental warming treatment and precipitation manipulation system to simulate climate change impact for Pinus densiflora seedlings based on a climate change scenario in Korea. Two-year-old seedlings were planted in a nursery in April, 2013. The air temperature of warmed plots (W) was set to increase by $3.0^{\circ}C$ compared to control plots (C) using infrared lamps from May, 2013. The three precipitation manipulation consisted of precipitation decrease using transparent panel (-30%; $P^-$), precipitation increase using pump and drip-irrigation (+30%; $P^+$) and precipitation control (0%; $P^0$). Initially, the air temperature was $2.2^{\circ}C$ higher in warmed plots than in control plots and later air temperature was maintained close to the target temperature of $3.0^{\circ}C$. The average soil temperature was $3.1^{\circ}C$ higher in warmed plots than in control plots. Also the average soil moisture content after the precipitation manipulation increased by 13.9% in $P^+W$ and decreased by 10.0% in $P^-W$ compared to $P^0W$, and increased by 23.7% in $P^+C$ and decreased by 7.6% in $P^-C$ compared to $P^0C$. It was confirmed that the open-field experimental warming and precipitation manipulation system was properly designed and operating.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1500-1509
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• 2014

The object of this study was to investigate the inhibitory effects of chios mastic gum (MG) on gastric acid secretion in an ethanol-induced SD rat model and primary parietal cells. Rats were randomly divided into four groups: Vehicle (normal group), Control (treated with ethanol), MG50 (treated with ethanol and mastic gum at 50 mg/kg b.w), MG100 (treated with ethanol and mastic gum at 100 mg/kg b.w). Groups treated with both MG50 and MG100 showed attenuation of gastric mucosal injury, sub-epithelial loss, hemorrhaging, and gastric juice secretion. We also examined the acidity of gastric juice during gastric injury. Oral administration of both MG50 and MG100 significantly decreased acidity of gastric juice by % and %, respectively. To examine the stimulatory factors related to gastric acid secretion, mRNA expression levels of H2r, M3r, CCK2r, and $H^+/K^+$ ATPase were measured by real-time PCR. Compared with a vehicle group, mRNA expression levels of H2r, CCK2r, and $H^+/K^+$ ATPase clearly increased in the control group. However, levels of H2r, CCK2r, and $H^+/K^+$ ATPase slightly but significantly decreased in MG-treated groups compared with control. Blood level of histamine significantly decreased in MG-treated groups, which indicates the involvement of MG on in histamine-related acid secretion. To identify the mode of action of MG in regulating histamine-related pathways, intracellular level of cAMP and mRNA levels of H2r, M3r, CCK2r, and $H^+/K^+$ ATPase were measured in primary parietal cells. While mRNA levels of M3r and CCK2r remained unchanged, levels of H2r and $H^+/K^+$ ATPase significantly decreased upon MG treatment. Subsequently, intracellular levels of cAMP decreased. These results suggest that mastic gum has the ability to inhibit gastric acid secretion by regulating a histamine-related pathway.

• Journal of Chest Surgery
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• v.39 no.7 s.264
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• pp.505-510
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• 2006

Background: Small animal cardiopulmonary bypass (CPB) model would be a valuable tool for investigating path-ophysiological and therapeutic strategies on bypass. The main advantages of a small animal model include the reduced cost and time, and the fact that it does not require a full scale operating environment. However the rat CPB models have a number of technical limitations. Effective maintenance and control of core temperature by a heat exchanger is among them. The purpose of this study is to confirm the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. Material and Method: The miniature circuit consisted of a reservoir, heat exchanger, membrane oxygenator, roller pump, and static priming volume was 40 cc, Ten male Sprague-Dawley rats (mean weight 530 gram) were divided into two groups, and heat exchanger (HE) group was subjected to CPB with HE from a cardioplegia system, and control group was subjected to CPB with warm water circulating around the reservoir. Partial CPB was conducted at a flow rate of 40 mg/kg/min for 20 min after venous cannulation (via the internal juglar vein) and arterial cannulation (via the femoral artery). Rectal temperature were measured after anesthetic induction, a ter cannulation, 5, 10, 15, 20 min after CPB. Arterial blood gas with hematocrit was also analysed, 5 and 15 min after CPB. Result: Rectal temperature change differed between the two groups (p<0.01). The temperatures of HE group were well maintained during CPB, whereas control group was under progressive hypothermia, Rectal temperature 20 min after CPB was $36.16{\pm}0.32^{\circ}C$ in the HE group and $34.22{\pm}0.36^{\circ}C$ in the control group. Conclusion: We confirmed the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. This model would be a valuable tool for further use in hypothermic CPB experiment in rats.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.286-293
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• 2016

BACKGROUND: 18% of difenoconazole+iminoctadin triacetate microemulsion (3%+15%) formulation were mixed and sprayed as closely as possible to normal practice on the ten of farms located in the Youngju of South Korea. Patches, cotton gloves, socks, masks and XAD-2 resin were used to measure the potential exposure for applicators wearing standardized whole-body outer and inner dosimeter (WBD). This study has been carried out to determine the dermal and inhalation exposure to difenoconazole during preparation of spray suspension and application with a power sprayer on a grape orchard. METHODS AND RESULTS: A personal air monitor equipped with an air pump IOM sampler and cassette and glass fiber filter were used for inhalation exposure. The field studies were carried out in a grape orchard. The temperature and relative humidity were monitored with a thermometer and a hygrometer. Wind speed was measured using a pocket weather meter. All mean field fortification recoveries were between 97.3% and 119.6% in the level of 100 LOQ (limit of quantification) while the LOQ for difenoconazole was $0.025{\mu}g/mL$ using HPLC-UVD. The arms exposure to difenoconazole for the mixer/loader (0.0794 mg) was higher than other body parts (head, hands, upper body, legs). The exposure to difenoconazole in the legs for applicator (3.78 mg) was highest in the parts of body. The dermal exposure for mixer/loader and applicator were 0.02 and 2.28 mg on a grape orchard, respectively. The inhalation exposure during application was estimated as 0.02 mg. The ratio of inhalation exposure to dermal exposure was equivalent to 0.9% of the dermal exposure. CONCLUSION: The inhalation exposure for applicator indicated $18.8{\times}10^{-3}mg$, which was level of 0.9% of the dermal exposure (2.28 mg). Operator exposure (0.004 mg/kg bw/day) to difenoconazole during treatment for grape is calculated as 2.5% of the established AOEL (0.16 mg/kg bw/day).

• Progress in Medical Physics
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• v.25 no.2
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• pp.116-121
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• 2014

Next future, The bio technology will be a rapidly developing. This paper is the scattering beam measurement of the red blood cell (RBC) and the fabrication of the micro cell biochip using the bio micro electro mechanical system (Bio-MEMS) process technology. The Major process method of Bio-MEMS technology was used the buffered oxide etchant (BOE), electro chemical discharge (ECD) and ultraviolet sensitive adhesives (UVSA). All experiments were the 10 times according to the process conditions. The experiment and research are required the ultraviolet expose, the micro fluid current, the cell control and the measurement of the output voltage Vpp (peak to peak) waveform by scattering angles. The transmitting and receiving of the laser beam was used the single mode optical fiber. The principles of the optical properties are as follows. The red blood cells were injected into the micro channel. The single mode optical fiber was inserting in the guide channel. The He-Ne laser beam was focusing in the single mode optical fiber. The transmission He-Ne laser beam is irradiating to the red blood cells. The manufactured guide channel consists of the four inputs and the four outputs. The red blood cell was allowed with the cylinder pump. The output voltage Vpp waveform of the scattering beam was measured with a photo detector. The receiving angle of the output optical fiber is $0^{\circ}$, $5^{\circ}$, $10^{\circ}$, $15^{\circ}$. The magnitude of the output voltage Vpp waveform was measured in the decrease according to increase of the reception angles. The difference of the output voltage Vpp waveform is due differences of the light transmittance of the red blood cells.

• Journal of Acupuncture Research
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• v.26 no.6
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• pp.101-110
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• 2009

Objectives : We developed and proposed a guideline for safety and performance assessment of electric cupping apparatus(Class 2 medical device). Methods : We drafted the guideline for safety and performance assessment of electric cupping apparatus by referring the existing standards and guideline, based on online questionnaire for Korean medical doctors and measurement data from commercially available products. Physical dimension of cups and inner vacuum pressure were acquired for the measurement in order to achieve the purposes. Results : This guideline only can be applied to electric cupping apparatus for enhancing blood circulation by employing negative pressure generated by electricity. Seven items of appearance and label, operation test of pump, variation test of input electricity, vacuum level test, vacuum sustain test, cup-size dependent test, noise level test are suggested for evaluation subjects and methods required for electric cupping devices. Requirements for the design and development of electric cupping devices are suggested: vacuum level indicator, vacuum generation rate, pressure control, valve detachment stability, cup comparability, safety measure, surge protection, user friendliness, instruction for use (IFU). Conclusions : We proposed a guideline for safety and performance assessment of electric cupping apparatus to improve the quality of relating products and aid the commercialization of them, by aiming higher industrial competitiveness of the medical device sectors in Korea. Discussion with related institutes such as industry, academy and government is further required. Public hearings also need to be held prior to the establishment of a final guideline and standard.