• Korean Journal of Acupuncture
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• v.22 no.1
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• pp.95-108
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• 2005

Objective : In the present study, the effect of electroacupuncture (EA) applied to several acupoints and non-acupoint in CFA-induced knee arthritis was examined. Methods : A common source of persistent pain in humans is arthritis. Arthritis was induced by injection of CFA $125\;{\mu}l$ into knee joint cavity under enflurane anesthesia. The rat subsequently showed swelling of the ankle and a reduced stepping force of the affected limb for the next several days. The reduced stepping force of the limb was presumably due to a painful knee. EA was applied to either of $LR_2,\;LI_4$, or non-acupoint on the contralateral forelimb for 30 min under gaseous anesthesia. After the termination of EA, behavioral tests measuring stepping force were periodically conducted during the next 4 h. Results : EA applied to $LR_2$ point produced a significant improvement of stepping force of the affected foot lasting for at least 2 h. However, neigher $LI_4$ point nor non-point produced any significant increase of weight bearing force. The improvement of stepping pressure was interpreted as an analgesic effect. The analgesic effect was specific to the acupuncture point since the analgesic effect on CFA-induced knee arthritic pain model could not be mimicked by EA applied to a point, $LI_4$ or non-acupoint. In addition, both NO production and iNOS protein expression increased by arthritis were suppressed by EA applied to $LR_2$ point. Conclusion : These data suggest that EA produces a potent analgesic effect in the rat model of CFA-induced knee arthritis. This analgesic effect is produced by applying EA to an acupoint at opposite side from the painful area in a stimulus point-specific way.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.259-265
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• 2005

Central diabetes insipidus (DI) is a syndrome characterized by thirst, polydipsia and polyuria. Langerhans cell histiocytosis is one of the etiologies of DI. Recently we experienced a central DI associated with Langerhans cell histiocytosis. The 44 years old female patient complained right hip pain, polydipsia and polyuria. We carried out water deprivation test. After vasopressin injection, urine osmotic pressure was increased from 109 mOsmol/kg to 327 mOsmol/kg (300%). Brain MRI showed a thickened pituitary stalk and air bubble like lesions sized with 5cm, 7cm was shown on fifth L-spine and right hip bone at hip bone CT. CT guided biopsy revealed abnormal histiocytes proliferation and abundant lymphocytes. The final diagnosis was central DI associated with systemic Langerhans cell histiocytosis invading hip bone, L-spine and pituitary stalk. Desmopressin and etoposide chemotherapy were performed to the patient.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.4
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• pp.81-88
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• 2013

It was designed and tested at the design point that an oxidizer rich preburner for a staged combustion liquid rocket engine propelled by kerosene and LOx. The oxidizer rich preburner was designed as some of LOx injected from the mixing head was burned with kerosene and the rest of LOx injected from injection holes in the regenerative cooling chamber was vaporized by combustion gas. The preburner is operated at OF ratio of 60 and combustion pressure of 20 MPa. The Preburner has a honey-comb type mixing head with simplex swirl injectors, a turbulence ring improving combustion stability and uniformity of product gas temperature distribution, and a nozzle simulating the duct. With the combustion test results at the design point, the oxidizer rich preburner showed high combustion stability and uniformity of product gas temperature distribution.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.2
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• pp.1-10
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• 2018

This study investigated the acoustic forcing effects on the liquid column breakup length and the trajectory of liquid jets in crossflows. Cold-flow tests with a single hole circular nozzle injector were carried out by changing the injection pressure and acoustic forcing amplitude. Additionally, spray images were obtained at 12 phase angles to investigate the influence of the phage angle. The results revealed that the liquid column breakup lengths generally decreased under the acoustic forcing conditions, in comparison to those under the non-acoustic forcing conditions. However, they were not affected by the variation in the phase angles. On the contrary, it was found that the acoustic forcing hardly influenced the liquid column trajectories.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.381-387
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• 2008

The presence of non-condensable gases as an additional thermal resistance inside a refrigerating circuit has been found for a general refrigerator, The effect of non-condensable gases was varied by controlling the injection amount of dry air into the refrigerating circuit to increase a thermal resistance. Energy consumption tests for the refrigerator were conducted under the various amounts of non-condensable gases. The tested refrigerating circuit was the household refrigerator. As the molar fraction of non-condensable gases was increased from 0% to 1.46%, the amount of energy consumption was found to increase up to 25%. The increase of the amount of non-condensable gases in refrigerating circuit was found to result in increasing the condensation temperature at the condenser and decreasing the evaporation temperature at the evaporator, which were presumably caused by the low specific heat and increased partial pressure of non-condensable gas.

• Research in Vestibular Science
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• v.17 no.4
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• pp.142-151
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• 2018

Objectives: Excitability o medial vestibular nucleus (MVN) in the brainstem can be affected by changes in the arterial blood pressure. Several animal studies have demonstrated that acute hypotension results in the alteration of multiunit activities and expression of cFos protein in the MVN. In the field of extracellular electrophysiological recording, tetrode technology and spike sorting algorithms can easily identify single unit activity from multiunit activities in the brain. However, detailed properties of electrophysiological changes in single unit of the MVN during acute hypotension have been unknown. Methods: Therefore, we applied tetrode techniques and electrophysiological characterization methods to know the effect of acute hypotension on single unit activities of the MVN of rats. Results: Two or 3 types of unit could be classified according to the morphology of spikes and firing properties of neurons. Acute hypotension elicited 4 types of changes in spontaneous firing of single unit in the MVN. Most of these neurons showed excitatory responses for about within 1 minute after the induction of acute hypotension and then returned to the baseline activity 10 minutes after the injection of sodium nitroprusside. There was also gradual increase in spontaneous firing in some units. In contrast small proportion of units showed rapid reduction of firing rate just after acute hypotension. Conclusions: Therefore, application of tetrode technology and spike sorting algorithms is another method for the monitoring of electrical activity of vestibular nuclear during acute hypotension.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.1
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• pp.61-69
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• 2021

Background: Inferior alveolar nerve block (IANB) using lidocaine 2% is commonly used for anesthetizing primary mandibular molars; however, this technique has the highest level of patient discomfort compared to other local anesthesia techniques. Therefore, alternative anesthesia techniques are necessary. The aim of this study was to evaluate the efficacy of a single buccal infiltration of 4% articaine with IANB using 2% lidocaine, for the bilateral extraction of primary mandibular molars. Methods: The present study was conducted on 30 patients aged between 6 and 9 years, who required the extraction of bilateral primary mandibular molars. The patients were randomly divided into two groups as follows: In the first session, Group A received IANB with lidocaine 2% and group B received infiltration with articaine 4%. In the second session, another injection method was performed on the opposite side. The Wong-Baker Facial Pain scale (WBFPS), Face Leg Activity Cry, and Consolability (FLACC), and physiologic parameters were used to assess pain perception. Results: The independent t-test showed no statistically significant difference in blood pressure and heart rate before and after extraction (P > 0.05). The mean FLACC index in the lidocaine and articaine groups was 0.89 and 1.36, respectively; there was no statistically significant difference between them (P > 0.05). According to the results of the chi-square test, there was no statistically significant difference between the groups for WBFPS (P > 0.05). Conclusion: The articaine infiltration technique may be an alternative to the IANB for the extraction of primary mandibular molars.

• Journal of Chest Surgery
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• v.54 no.3
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• pp.200-205
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• 2021

Background: Various methods have been used to reduce postoperative pain after thoracic surgery. However, these methods may affect the patient's respiratory response and delay recovery from anesthesia. We aimed to evaluate the effects of fentanyl and remifentanil during extubation after video-assisted thoracic surgery (VATS). Methods: This study included 45 randomly-selected male patients who underwent VATS for pneumothorax between July 2011 and August 2012. We divided the participants into 3 groups: the F group, which received a bolus injection of 1.0 ㎍/kg of fentanyl; the R1 group, which received a 0.04 ㎍/kg/min remifentanil infusion; and the R2 group, which received a 0.08 ㎍/kg/min remifentanil infusion. Hemodynamics, pain, cough, consciousness level, and nausea were assessed for each group. Results: The number and severity of coughs were lower in the R1 and R2 groups than in the F group, and there were no differences between the R1 and R2 groups. Respiratory depression and loss of consciousness were not observed in any of the patients, and there were no differences in hemodynamics. Conclusion: In comparison with fentanyl, remifentanil did not result in a wide fluctuation of blood pressure and heart rate upon emergence from general anesthesia. Moreover, remifentanil contributed to cough suppression and postoperative pain control. Remifentanil seems to be a safe and effective analgesic after VATS.

• 대한상한금궤의학회지
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• v.13 no.1
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• pp.21-44
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• 2021

Objective : This study aimed to assess the preventive effect of Bupleuri Radix aqueous extracts (BR) and red koji-fermented BR (fBR) in lipopolysaccharide (LPS)-induced acute lung injury in a rat model. Methods : Rats were administered 30, 60, or 120 mg/kg/day of fBR for 28 days before LPS treatments. All rats were sacrificed 5 h after LPS treatment (500 ㎍/head, intratracheal instillation). Body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters (pH, partial pressure [Pa] of O2, PaCO2), bronchoalveolar lavage fluid (BALF) protein, lactate dehydrogenase (LDH), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), total cell numbers, neutrophil/alveolar macrophage ratios, lung malondialdehyde (MDA), and myeloperoxidase (MPO) were measured. In addition, histopathological changes including the luminal surface of alveoli (LSA), thickness of alveolar septum, and number of polymorphonuclear neutrophils (PMNs) were checked. Results : LPS injection led to increases in lung weights, pulmonary transcapillary albumin transit, BALF protein, LDH, TNF-α and IL-1β contents, total cells, neutrophil and alveolar macrophage ratios, lung MDA, MPO, alveolar septum thickness, and PMNs, and decreases in PaCO2 and pH of arterial blood and LSA. However, these LPS-induced acute lung injuries were inhibited by pretreatment of 30, 60, and 120 mg/kg of fBR. The most favorable effects were seen with 30 mg/kg fBR as compared with 60 mg/kg of α-lipoic acid and BR. Conclusions : fBR showed preventive effects on LPS-induced acute lung injury, which resembles acute respiratory distress syndrome. The mechanisms of action were likely via antioxidant and anti-inflammatory means.

• Journal of the Korea Society of Computer and Information
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• v.28 no.1
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• pp.121-127
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• 2023

In this study, the design conditions and CFD analysis results are compared and reviewed in SCR that can optimally reduce nitrogen compounds. To this end, it was analyzed and compared using CFD to see if the design criteria were satisfied for the shell and tube areas of the boiler. In the SCR system, the analysis area is the gas/air heat exchanger on the shell side, and eight tubes of the gas/air heat exchanger on the tube side. Through CFD analysis, the gas velocity distribution on the primary catalyst side of the SCR system was designed to be 2.4%, and the NH3/NOx molar ratio distribution was 3.7%, which satisfied the design criteria. In addition, the uniformity of the temperature distribution was confirmed and the required condition of 260℃ or higher was satisfied. The angle of the gas entering the catalyst met the design conditions at 2.9 degrees, and the pressure loss that occurred also satisfied the design requirements. Through this CFD analysis, it was confirmed that it was designed and operated by satisfying the design conditions required for each area.