• The Korean Journal of Physiology and Pharmacology
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• v.4 no.6
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• pp.515-523
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• 2000

Polymorphonuclear leukocytes (PMNs) play an important role in myocardial ischemia/reperfusion (MI/R) injury. Moreover, platelets are also important blood cells that can aggravate myocardial ischemic injury. This study was designed to test the effects of PMNs and platelets separately and together in provoking cardiac dysfunction in isolated perfused rat hearts following ischemia and reperfusion. Additional control rat hearts were perfused with $75{\times}10^6$ PMNs, with $75{\times}10^6$ platelets, or with $75{\times}10^6\;PMNs+75{\times}10^6$ platelets over a five minute perfusion followed by a 75 min observation period. No significant reduction in coronary flow (CF), left ventricular developed pressure (LVDP), or the first derivative of LVDP (dP/dt max) was observed at the end of the observation period in any non-ischemic group. Similarly, global ischemia (I) for 20 min followed by 45 minutes of reperfusion (R) produced no sustained effects on the final recovery of any of these parameters in any group of hearts perfused in the absence of blood cells. However, I/R hearts perfused with either PMNs or platelets alone exhibited decreases in these variables of $5{\sim}10%$ (p＜0.05 from control). Furthermore, I/R hearts perfused with both PMNs and platelets exhibited decreases of 50 to 60% in all measurements of cardiac function (p＜0.01). These dual cell perfused I/R hearts also exhibited marked increases in cardiac myeloperoxidase (MPO) activity indicating a significant PMN infiltration, and enhanced P-selectin expression on the coronary microvascular endothelium. All cardiaodynamic effects as well as PMN accumulation and P-selectin expression were markedly attenuated by a recombinant soluble PSGL-1 which inhibits selectin mediated cell adhesion. These results provide evidence that platelets and PMNs act synergistically in provoking post-reperfusion cardiac dysfunction, and that this may be largely due to cell to cell interactions mediated by P-selectin. These results also demonstrate that a recombinant soluble PSGL-1 reduces myocardial reperfusion injury by platelet and PMNs interaction.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.33-37
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• 2009

Purpose: Liver transplantation is considered as the treatment of choice in many acute and chronic liver diseases, and it is becoming more common. Since successful microscopic anastomosis of hepatic artery is a crucial requirement of successful liver transplantation, we studied and analyzed the result of hepatic artery anastomosis of liver transplantation in our liver transplantation center. Methods: 145 liver transplantations were performed between February 2005 and May 2008. Male to female ratio of the liver transplantation recipients was 3.4 : 1. Anastomosis of portal vein, hepatic vein and biliary tract was performed by the general surgeon, and anastomosis of hepatic artery was performed by the plastic surgeon under the loupe or microscopic vision. After the hepatic artery was reconstructed, anastomosed site status and flow were checked with Doppler ultrasonography intraoperatively and with contrast enhanced CT or angiography postoperatively if necessary. Results: Out of 145 liver transplantations, cadaveric liver donor was used 37 cases and living donor liver transplantation was performed 108 cases including the 2 dual donor liver transplantations. As for the baseline diseases that resulted in the liver transplantation, there were 57 cases of liver cirrhosis and hepatocellular carcinoma due to hepatitis B, taking up the greatest proportion. Single donor hepatic artery was used in 114 cases, and mean artery diameter was 2.92 mm and mean artery length was 24.25 mm. Hepatic artery was used as the recipient artery in every case except the 8 cases in which gastroepiploic artery was used as alternative. Out of 145 cases of hepatic artery anastomosis, 3 cases resulted in the thrombosis of the hepatic artery, requiring thrombectomy and re - anastomosis. In all 3 cases, thrombosis was found in left hepatic artery and there was no past history of hepatic artery chemoembolization. Conclusion: Incidence of hepatic artery thrombosis after the anastomosis of hepatic artery during liver transplantation was 2.1%, which is considered sufficiently low.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.12
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• pp.1327-1336
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• 2012

In this paper, the dual-faced monopole antenna, which is arranged by numerous rectangular ring patches in sequence for the multi-bands is proposed. The ring type structure of the patch can be increased the bandwidth. Therefore the bandwidth and beam width are improved by using multiple arrayed patches. When the ring type patches are inserted serially, the resonance frequencies are occurred by the current flow from the first ring patch. It is possible because the gap between the patches is very narrow. In addition, if the patches are composed on the same plane as the feed-line, fabrication could be very difficult because the gap between the patches is extremely narrow. The thickness and permittivity of the antenna, moreover, are very important parameters because both sides of the substrate are used. We finally found the optimal thickness and permittivity to generate the coupling effect by simulation. All patches are consisted of 4-steps which the patch size was decreased 85 % by each step. In conclusion, the resonant frequency bands are 1.75~2.6 GHz(850 MHz), 3.24~3.46 GHz(220 MHz), 3.8~4.0 GHz(200 MHz), and 4.4~4.9 GHz(500 MHz).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.12
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• pp.1057-1064
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• 2014

Recently, there has been a growing interest in sustainable energy. One method that has been used is an organic Rankine cycle using conventional turbine technology with a low-temperature waste heat source. A 200-kW organic Rankine cycle (ORC) system was designed for a waste heat recovery application using R245fa as the working fluid. A radial turbine running at 15,000 rpm was employed to generate more than 200 kW with an expansion ratio of nine. Because an ORC turbine uses a refrigerant as the working fluid, the ideal gas law was not employed to design the turbine. In addition, the complexity of the molecular structure of R245fa made it difficult to design the turbine. Because R245fa has an Ma value of one at a low velocity for the working fluid (about 1/3 of the speed of sound in air) at about $100^{\circ}C$, it easily reaches a supersonic flow condition with a small pressure expansion. To increase the efficiency of the turbine, a dual stage radial-type turbine with a subsonic speed was suggested. This paper will describe the design procedure and performance evaluation of the ORC turbine using R245fa.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.419-425
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• 2019

The objective of this study was to investigate the cooling performance characteristics of a hybrid refrigeration system in a heavy duty vehicle. The tested hybrid refrigeration system had additionally an electric compressor besides the present mechanical compressor for selective use according to the operating conditions. The applied electric compressor was a scroll type and with 18.0 cc displacement. In order to analyze the performance characteristics of the hybrid refrigeration system with respect to the cooling capacity and Coefficient of Performance (COP), other components, including two different types of compressors, were installed and tested under various operating conditions such as compressor speed and air flow rate of the evaporator. When the electric compressor was operated at 4,500 rev/min, the cooling capacity was about 4.0kW and COP was 3.5. When the mechanical compressor was operated, whereas the cooling capacity was higher than the electric controlled compressor, COP was lower due to the larger displacement and higher power consumption. To analyze the hybrid system operating characteristics due to reasonable cooling capacity with electric compressor operation, the mechanical compressor and electric compressor were operated by turns every 10 minutes under certain system operating conditions. Because surge pressure occurred when both compressors were switched on, the operating strategy required some time to balance the system pressure.

• Animal Bioscience
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• v.37 no.3
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• pp.509-521
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• 2024

Objective: It was shown that microRNAs (miRNAs) play an important role in milk protein synthesis. However, the post-transcriptional regulation of casein expression by exogenous miRNA (xeno-miRNAs) in ruminants remains unclear. This study explores the regulatory roles of alfalfa xeno-miR162 on casein synthesis in bovine mammary epithelial cells (bMECs). Methods: The effects of alfalfa xenomiR-162 and G protein subunit gamma 11 (GNG11) on proliferation and milk protein metabolism of bMECs were detected by 5-Ethynyl-2'-Deoxyuridine (EdU) staining, flow cytometry, cell counting kit-8 (CCK-8), enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot. Dual-luciferase reporter assay was used to verify the targeting relationship between GNG11 and xenomiR-162. Results: Results showed that over-expression of xenomiR-162 inhibited cell proliferation but promoted apoptosis, which also up-regulated the expression of several casein coding genes, including CSN1S1, CSN1S2, and CSN3, while decreasing the expression of CSN2. Furthermore, the targeting relationship between GNG11 and xenomiR-162 was determined, and it was confirmed that GNG11 silencing also inhibited cell proliferation but promoted apoptosis and reduced the expression of casein coding genes and genes related to the mammalian target of rapamycin (mTOR) pathway. Conclusion: Alfalfa xenomiR-162 appears to regulate bMECs proliferation and milk protein synthesis via GNG11 in the mTOR pathway, suggesting that this xeno-miRNA could be harnessed to modulate CSN3 expression in dairy cows, and increase κ-casein contents in milk.

• Journal of Korean Academy of Nursing
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• v.23 no.1
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• pp.118-129
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• 1993

In order to approach the nursing care of clients who are using oriental medicine and to understand the perception of the client who uses oriental medicine practices and the need to develop a model of nursing related to oriental medicine it is important to examine the major nursing concepts as they are found in oriental medicine and as they are differently defined according to the basic thought, theory and philosophical perspectives between East and West. Oriental medicine developed based on Sung Confucianism the teachings of Chut-zu, especially Tai-Chi-Tu Shuo and energy thought which are similar to traditional Korean Sasang Constitutional medicine. The basic theory on which oriental medicine is build is the theory of the five elements of Yin / Eum-Yang Theory(cosmic dual forces) and Meridian Theory. The most important attribute of Yin Yang is the concept of duality, confrontation and dependence, within Yin Yang but which do not exist separately. That is, the universe is a vast, indivisible entity within which all things exist in harmonious interdependence and balance. Harmony is achieved only when the two primorial forces, Yin and Yang, are brought into perfect balance. Each is contained within the other and there is a continuing interchange between the two. This also applies to the human body including human health which is defined as balanced harmony. The most universal connection of Yin and Yang is found in the universe where the five elements of life, fire, water, earth, wood and metal can be explained as having either Yin or Yang and therefore being in a state of connectedness but systematically circulating between the two, that is essentalilly one (the control of the unified ) or as coexistant poles of individual wholes (the pluralism of Yin Yang Theory) so that it is all unified(balanced) in the Great Absoulte. Human beings also maintain a balance of Yin and Yang in the five elements and this relationship is very important in approaching ·oriental medicine, The meridians are the channels in the body through which the life force flow throughout the body. In oriental medicine the meridians are seen as the railroad, the acupuncture points on the meridians as the stations and energy as the train. In the normal healthy organism, all are maintained in balance and in a contiuous circulation of energy. illness is the result of the energy flow becoming disarranged. Although practitioners of oriental medicine approach the client differently than do practitioners of Western medicine and their method of examining the patient is different, the basic objectives of the examination are the same for practitioners of both types of medicine. Therefore if each could be used to supplement the defiencies in the other and achieve a harmonious cooperation between the two, a higher level of care which is culturally appropriate to korean culture could be achieved. The traditional korean concept of health is a naturalistic view which emphasizes being in harmony with nature. Any manifestation of disease is considered a sign that the body is in a state of disequilibrium and is thus no longer in harmony with the universe. The wholistic view of the world held by practitioners of oriental medicine can be used by nursing in the development of a world view of nursing in which the human being is seen within the macrocosm as part of the natural phenomenon of the universe and but also as a microcosm of the universe, a universe which is a vast and indivisible entity within which all things exist in harmonious interdependence and balance. Interaction between human beings and their environment and the relationship of this interaction to health are concepts that are also found in nursing. Nursing views human brings, not as an accumulation of separate cells and organs but, as unified wholes interacted in very close relationship nth their environment. Nursing also maintains a view of human beings in which emphasis is placed on the role of the mind in explaining the concepts of harmony and balance in health. Although there are differences between oriental medicine and nursing in approaches to clients, the basic point of view and philosophy have many fundamental similarites. An understanding of the basic thought and philosophy of oriental medicine if applied to nursing, would allow for the development, not only of nursing related to oriental medicine, but of a nursing theory appropriate to the korean context.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.39-43
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• 2008

Purpose: There are various methods to diagnose hemangioma, such as ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine. However, by development of SPECT imaging, the blood-pool scan using $^{99m}Tc$-labeled red blood cell has been used, because it was non-invasive and the most economical method. Therefore, in this study, we proposed that the usefulness of $^{99m}Tc$-RBC scan and SPECT of the head and neck to diagnose unlocated hemangiomas. Materials and Methods: $^{99m}Tc$-RBC scan and SPECT was performed on 6 patients with doubtful hemangioma (4 person, head; 1 person, neck; 1 person, another). We labeled radiopharmaceutical using modified in vivo method and then, centrifuged it to remove plasma. After a bolus injection of tracer, dynamic perfusion flow images were acquired. Then, anterior, posterior, both lateral static blood-pool images were obtained as early and 4 hours delayed. SPECT was progressed 64 projections per 30 seconds. Each image was interpreted by physicians, Nuclear medicine specialist, and technologist blinded to patient's data. Results: In 5 patients of all the radioactivity of doubtful site didn't change in flow images, but, in blood-pool, delayed and SPECT images, it was increased. So, it was a typical hemangioma finding. The size of lesion was over 2 cm, and it could discriminate as comparing to the delayed and SPECT imaging. On the other hand, in 1 patient, the radioactivity was increased in blood-pool images, but, not in delayed and SPECT images, so, it was proved no hemangioma. Conclusion: Using $^{99m}Tc$-RBC Scan and SPECT, we could diagnose the hemangiomas in head and neck, as well as, liver, more non-invasive, economical, and easy. Therefore, it considered that $^{99m}Tc$-RBC scan and SPECT would offer more useful information for diagnosis of hemangioma, rather than otherimaging such as US, CT, MRI.

• Progress in Medical Physics
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• v.9 no.3
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• pp.163-173
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• 1998

Nuclear medicine emission computed tomography(ECT) can be very useful to diagnose early stage of neuronal diseases and to measure theraputic results objectively, if we can quantitate energy metabolism, blood flow, biochemical processes, or dopamine receptor and transporter using ECT. However, physical factors including attenuation, scatter, partial volume effect, noise, and reconstruction algorithm make it very difficult to quantitate independent of type of SPECT. In this study, we quantitated the effects of attenuation and scatter using brain SPECT and three-dimensional brain phantom with and without applying their correction methods. Dual energy window method was applied for scatter correction. The photopeak energy window and scatter energy window were set to 140ke${\pm}$10% and 119ke${\pm}$6% and 100% of scatter window data were subtracted from the photopeak window prior to reconstruction. The projection data were reconstructed using Butterworth filter with cutoff frequency of 0.95cycles/cm and order of 10. Attenuation correction was done by Chang's method with attenuation coefficients of 0.12/cm and 0.15/cm for the reconstruction data without scatter correction and with scatter correction, respectively. For quantitation, regions of interest (ROIs) were drawn on the three slices selected at the level of the basal ganglia. Without scatter correction, the ratios of ROI average values between basal ganglia and background with attenuation correction and without attenuation correction were 2.2 and 2.1, respectively. However, the ratios between basal ganglia and background were very similar for with and without attenuation correction. With scatter correction, the ratios of ROI average values between basal ganglia and background with attenuation correction and without attenuation correction were 2.69 and 2.64, respectively. These results indicate that the attenuation correction is necessary for the quantitation. When true ratios between basal ganglia and background were 6.58, 4.68, 1.86, the measured ratios with scatter and attenuation correction were 76%, 80%, 82% of their true ratios, respectively. The approximate 20% underestimation could be partially due to the effect of partial volume and reconstruction algorithm which we have not investigated in this study, and partially due to imperfect scatter and attenuation correction methods that we have applied in consideration of clinical applications.

• Journal of Dairy Science and Biotechnology
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• v.33 no.4
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• pp.263-269
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• 2015

Various carbohydrates (lactose, glucose, and fructose), lactic acid, uric acid, and acetoin were separated on a ZORBAX Carbohydrate Analysis column using the Agilent 1200 HPLC ChemStation$^{TM}$, and were identified according to retention times with 325 Dual Wavelength UV-Vis Detector and Refractive Index Detector with 0.013 N $H_2SO_4$ at a flow rate of 0.8 mL/min. In addition, the lactase activity of four commercial probiotic lactic acid bacteria during 6-hour incubation was determined using a high-performance liquid chromatography (HPLC) method. Among the tested samples, Bifidobacterium animalis subsp. lactis showed the greatest lactase activity, followed by Lactobacillus rhamnosus and Lactobacillus casei, with Streptococcus salivarius subsp. thermophilus showing the lowest activity. Therefore, this HPLC technique shows potential for evaluating the fermentation processes of probiotic lactic acid bacteria and could simultaneously confirm the degree of ripening in various fermented dairy foods within only a half hour.