• Title/Summary/Keyword: Mean Pressure Control

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The Experimental Study of the Interaction Between the Flow rind Temperature Field and a Boundary Layer Due to a Variety of tole Height of a Vortex Generator (와동 발생기 높이 변화에 대한 경계층 내의 유동장과 온도장에 관한 실험적 연구)

  • Gwon, Su-In;Yang, Jang-Sik;Lee, Gi-Baek
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.1
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    • pp.82-93
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    • 2002
  • The effects of the interaction between the flow and temperature field and a boundary layer due to a variety of the height of a vortex generator are experimentally investigated. The test facility consists of a boundary-layer wind tunnel with the vortex generator protruding from the bottom surface. In order to control the strength of the longitudinal vortices, the angle of attack and the spacing distance of the vortex generator are 20 degree and 40 mm, respectively. The height of the vortex generator (H) is 15 mm, 20 mm and 30 mm and the cord length of it is 50 mm. Three-component mean velocity measurements are made using a 5-hole probe system and the surface temperature distribution is measured by the hue capturing method using thermochromatic liquid crystals. By using the method mentioned above, the following conclusions are obtained from the present experiment. The boundary layer is thinned in the downwash region where the strong downflow and the lateral outflow of the boundary layer fluid occur and thickened in the upwash re,3ion where the longitudinal vortex sweeps low momentum fluid away from the bottom surface. In case that the height of the vortex generator increases, the averaged circulation and the maximum vorticity of the vortex pair decrease. The contours of the non-dimensional temperature show the similar trends fur all the cases (H=15 mm, 20 mm and 30 mm). The peak augmentation of the distribution of the local non-dimensional temperature occurs in the downwash region near the point of minimum boundary-layer thickness.

Dietary and Lifestyle Factors Associated with Hypertension in Korean Adolescents -Based on 2005 Korean National Health and Nutrition Examination Survey- (한국 청소년의 고혈압과 관련된 식사 및 생활양식요인 분석 -2005년 국민건강.영양조사 자료에 근거하여-)

  • Kim, Kil-Lye;Son, Sook-Mee;Kim, Hye-Kyeong
    • Korean Journal of Community Nutrition
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    • v.16 no.4
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    • pp.439-453
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    • 2011
  • This study was performed to determine dietary and lifestyle factors associated with hypertension in Korean adolescents. Study subjects were 12~19 years (n = 521) adolescents who participated in the 2005 Korean National Health and Nutrition Examination Survey (KNHANES III). Subjects were divided into the hypertensive group (HG, n = 102) and normotensive group (NG, n = 419) by '2007 Korean children and adolescents growth standard' and the relationships between blood pressure and physical measurement, nutrients intakes, eating behaviors and health related factors were analyzed. HG showed significantly higher levels in weight, waist circumference and BMI than NG. The amount of nutrient intakes was not different between NG and HG. Index of nutritional quality (INQ) for phosphate was higher in HG compared with NG. In both male and female HG, INQ for iron was higher but INQ for vitamin B1 was lower than NG. HG revealed higher consumption frequencies of snack, yoghurt, and ice cream compared with NG. In eating and behavioral factors, 'dinner with family', 'eat proper amount', 'keep Korean traditional diet', alcohol drinking, and mean alcohol intake were significantly different between the two groups. By logistic regression method, risk factors for hypertension revealed in this study were gender (male), age (15~19 years), BMI (${\geq}\;85$ percentile), and not keeping Korean traditional diet. These results suggest that education program for hypertension prevention in adolescents should include eating habits improvement and lifestyle modification as well as weight control.

Analysis of Nutritional Index of Frequently Consumed Fruits in South Korea (한국인 다빈도 섭취 과일의 영양관련 지수 분석)

  • Ryu, Ji-Hyun;Yim, Jung-Eun;Lim, Hyunjung;Choue, Ryowon
    • Journal of the Korean Society of Food Culture
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    • v.29 no.6
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    • pp.659-667
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    • 2014
  • Fruits are good sources of vitamins, minerals, fiber, and phytochemicals, which are known to reduce serum lipids, oxidative damage, and blood pressure as well as improve blood glucose control. The purpose of this study was to estimate nutrient quality indices of fruits by carrying out a critical analysis of pre-existing methods according to their nutritional compositions. Four methods were used to assess the nutrient indices of 26 fruits, which are frequently consumed by Koreans based on the fourth Korean National Health and Nutrition Examination Survey (2009). Naturally nutrient rich score (NNR), nutrient rich food (NRF), nutrient adequacy score (NAS), and nutrient density score (NDS) were used to calculate nutrient quality indices. The Korean Nutrition Society Food Composition database of fruits based on 100 g edible portions was used. The algorithm of each method included the mean percentage of daily values (Dietary Reference Intakes for Koreans, 2010) for particular nutrients based on consumption of 1,900 kcal/day. The relative score indicated that strawberries, kumquat, and lemon had high nutrient quality indices. In addition, mango, lemon, persimmon, strawberry, apricot, and tangerine fruits are rich in antioxidant nutrients such as ${\beta}$-carotene, vitamin C, vitamin E, and selenium. However, scores of nutrient quality indices did not imply that higher scores of particular fruits are superior. We suggest moderate seasonable consumption a variety of fruits. Our results can be used as a reference for consumers when they choose fruits.

Hypertension and Diabetes mellitus Management Effects of Community based Chronic Disease Management Program (일 지역 만성질환관리 건강포인트사업이 고혈압 및 당뇨병관리 지식에 미치는 효과)

  • Oh, Dae-Kyu;Kim, Yun-Mi;Lim, Ji-Young;Cheong, Won
    • Journal of Home Health Care Nursing
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    • v.19 no.1
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    • pp.74-82
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    • 2012
  • Purpose: The aim of this study is to evaluate the effects of community based chronic disease management program for managing hypertension and diabetes mellitus. Method: The subjects of this study were 1,000 clients, who participated in a city community based chronic disease management program. The data were collected by a phone survey directly, and selected from DB of community based chronic disease management program, indirectly. The data were analyzed by the STATA program, using descriptive statistics, t-test, and Multiple regression analysis. Results: The mean score of knowledge of hypertension was 4.33 and diabetes mellitus was 2.52. The affecting factors of knowledge of hypertension were the clinic visiting point and blood sugar. However, the affecting factors of knowledge of diabetes mellitus was core lab point, diastolic blood pressure, and blood sugar. Conclusion: the results of this study showed that knowledge of hypertension increased with higher level of education, and younger ages, while knowledge of diabetes mellitus increased with higher level education, more core lab point, younger ages, and in males. Therefore, to control the chronic diseases more effectively in a community, it is important to develop a more systematic education and self- managing programs, using collaboration of health centers and local clinics.

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Ahmed Valve Implantation for Early Glaucoma Treatment in Dogs (개의 초기 원발성 녹내장안에서 Ahmed valve 이식술의 적용)

  • Park, Shin-Ae;Jeong, Man-Bok;Park, Young-Woo;Kim, Won-Tae;Kim, Se-Eun;Seo, Kang-Moon
    • Journal of Veterinary Clinics
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    • v.25 no.5
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    • pp.385-390
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    • 2008
  • The purpose of this study was to compare the long term prognosis of Ahmed valve implantation and medical therapy in dogs with early primary glaucoma. The medical records of dogs with early primary glaucoma from the Veterinary Medical Teaching Hospital of Seoul National University between January 2005 and May 2008 were reviewed. Five dogs underwent Ahmed valve implantation and medical therapy was performed in six dogs. Breeds of the dogs included Shih Tzu(n = 7), American cocker spaniel(n = 2), and miniature poodle(n = 2). Adequate intraocular pressure(IOP) was better maintained in the Ahmed valve implantation group than in the medical treatment group throughout the follow-up period. Mean time for vision loss to develop after treatment in the Ahmed valve implantation group($198.0{\pm}115.4$ days) was significantly longer than that in medical treatment group($43.2{\pm}30.4$ days, p < 0.05). Post-operative complications included occlusion of the tube by fibrin in the anterior chamber (n = 1), fibrous capsule about the episcleral base of the device(n = 1), and dislocation of the valve body(n = 1). It is considered that Ahmed valve implantation is more effective strategy to control IOP and maintain vision than medical treatment in early glaucomatous dogs.

Effect of hypertention falling of functional GABA green tea (기능성 GABA차의 고혈압 강하효과)

  • Park, Jang-Hyun;Han, Sung-Hee;Shin, Mee-Kyung;Park, Keun-Hung;Li, Keun-Cheol
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.1
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    • pp.37-40
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    • 2002
  • GABA tea which was increased of GABA by anaerobic conditions in green tea leaves) was fed in the diet to spontaneously hypertensive rats(SHR). The mean systolic blood pressure of SHR fed a diet containing 1.5% GABA tea after 3 weeks was not different with zero day as 177.3mmHg. However, 1.5% green tea and control after 3 weeks were more increased 4.2 percents and 10 percents than in zero day. The plasma levels of aldosterone of SHR fed a diat containing 1.5% GABA green tea after 3 weeks was more decreased 2.5 times than in water treatment.

Performance and Ignition Characteristics of a Coaxial Swirl Injector using LOX-$GCH_4$ Propellant (액체산소/기체메탄 추진제를 사용하는 동축형 스월 인젝터의 성능 및 점화특성)

  • Kim, Do-Hun;Lee, In-Chul;Kim, Jin-Kon;Koo, Ja-Ye;Park, Young-Il
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.72-76
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    • 2010
  • To research and develop a high performance injector for LRE, it needs not only cold flow test, but also investigations of combustion performance, optimization of cyclogram and thermo-fluid dynamical characteristics of combustion flow field through hot-fire test. In this study, hot-fire test of LOX-CH4 coaxial swirl injector has been carried out using lab-scale hot fire test stand which can supply and control cryogenic propellant. Ignition and continuous combustion for LOX-$GCH_4$ propellant of 0.19 kg/s total mass flowrate and 2.80 O/F Ratio was achieved through cyclogram optimization. The mean combustion chamber pressure and thrust were measured as approximately 1.43 MPa and 38.7 kgf respectively.

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Continuous Intravenous Infusion of Morphine and Ketorolac for Postoperative Pain (Morphine과 Ketorolac의 지속적 정주에 의한 술후 통증 완화 효과)

  • Lee, Yong-Tae;Kim, Dong-Chan;Han, Young-Jin;Choe, Huhn
    • The Korean Journal of Pain
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    • v.6 no.1
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    • pp.32-39
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    • 1993
  • Despite their sometimes fatal complications such as respiratory depression when used for postoperative pain control, intravenous and epidural narcotics remain the mainstay of treatment regimens. Because of the problems, anesthesiologists are seeking alternatives. We compared the analgesic effect and complications of continuous intravenous morphine with ketorolac. Ketorolac is a non-steroidal agent with potent analgesics and moderate anti-inflammatory activity. Forty ASA physical status I or II patients were given morphine(20 patients) or ketorolac(20 patients):In the morphine group, an initial bolus dose of 2 mg i.v. was given followed by continuous infusion at a rate of 1 mg/hr for 48 hours. The ketorolac group was given initial bolus of 30 mg i.v. This was followed by continuous infusion at a rate of 3.75 mg/hr for 48 hours using a Baxter Daymate Infuser. We checked systolic, diastolic and mean arterial pressure, heart rate, visual analogue scale(VAS) and the Prince Henry Score(PHS). This was done before the initial bolus, at 5, 15, 30 and 60 min, at 2, 6, 12, 24 and 48 hours after administration. We observed the side effects nausea and vomiting, pruritus, hypotension, somnolence, urinary retention and respiratory depression. From our study we believe ketorolac in selected patients, is as effective as morphine in alleviating postoperative pain without side effects of morphine.

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General Pharmacology of LB71350, a New HIV-1 Pretense Inhibitor

  • Kim, Hee-Jin;Oh, Jeng-In;Park, Hee-Dong;Kang, Ju-Seop;Ko, Hyun-Chul;Lee, Chang-Ho
    • Biomolecules & Therapeutics
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    • v.7 no.3
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    • pp.271-277
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    • 1999
  • Safety evaluation of LB71350, a new HIV-1 protease inhibitor, was performed in mice, rats and dogs. For the general behavior of mice, LB71350 at an oral dose of 200 mg/kg did not show any significant effects on muscle tone and locomotor activity. In terms of central nervous system, at oral doses of 200 mg/kg and 1000 mg/kg, LB71350 inhibited acetic acid-induced pain response approximately 41% and 83% of control. respectively. At oral doses of 200 mg/kg and 500 mg/kg, it reduced the rectal body temperature in rats. Pentylenetetrazole-induced seizure in mice was slightly potentiated by oral administration of LB71350 at doses ranging from 200 mg/kg to 1000 mg/Ag. Single or five day treatment of LB71350 doubled the hexobarbital- induced sleeping time in mice at oral doses ranging from 50 mg/kg to 500 mg/kg. It did not cause any effects on gastric secretion and acidity in rat at oral doses of 200 mg/kg and 1000 mg/kg and also it did not change intestinal motility in mice up to 1000 mg/kg. Blood coagulation indices such as prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT) in rats were not affected by the treatment of LB71350 up to 500 mg/kg. LB71350 caused no significant effects on the cardiac output, stroke volume, heart rate, and mean blood pressure when infused intravenously to the anesthetized rats and dogs. Taken together, LB71350 at high oral doses caused significant pharmacological effects on the central nervous system and the hexobarbital-induced sleeping time.

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Sparing effect of tramadol, lidocaine, dexmedetomidine and their combination on the minimum alveolar concentration of sevoflurane in dogs

  • El-Hawari, Sayed Fathi;Oyama, Norihiko;Koyama, Yukako;Tamura, Jun;Itami, Takaharu;Sano, Tadashi;Yamashita, Kazuto
    • Journal of Veterinary Science
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    • v.23 no.4
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    • pp.53.1-53.9
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    • 2022
  • Background: Problems associated with using inhalational anaesthesia are numerous in veterinary anaesthesia practice. Decreasing the amount of used inhalational anaesthetic agents and minimising of cardiorespiratory disorders are the standard goals of anaesthetists. Objective: This experimental study was carried out to investigate the sparing effect of intravenous tramadol, lidocaine, dexmedetomidine and their combinations on the minimum alveolar concentration (MAC) of sevoflurane in healthy Beagle dogs. Methods: This study was conducted on six beagle dogs. Sevoflurane MAC was determined by the tail clamp method on five separate occasions. The dogs received no treatment (control; CONT), tramadol (TRM: 1.5 mg kg-1 intravenously followed by 1.3 mg kg-1 h-1), lidocaine (LID: 2 mg kg-1 intravenously followed by 3 mg kg-1 h-1), dexmedetomidine (DEX: 2 ㎍ kg-1 intravenously followed by 2 ㎍ kg-1 h-1), and their combination (COMB), respectively. Cardiorespiratory variables were recorded every five minutes and immediately before the application of a noxious stimulus. Results: The COMB treatment had the greatest sevoflurane MAC-sparing effect (67.4 ± 13.9%) compared with the other treatments (5.1 ± 25.3, 12.7 ± 14.3, and 40.3 ± 15.1% for TRM, LID, and DEX treatment, respectively). The cardiopulmonary variables remained within the clinically acceptable range following COMB treatment, although the mean arterial pressure was higher and accompanied by bradycardia. Conclusions: Tramadol-lidocaine-dexmedetomidine co-infusion produced a remarkable sevoflurane MAC-sparing effect in clinically healthy beagle dogs and could result in the alleviation of cardiorespiratory depression caused by sevoflurane. Cardiorespiratory variables should be monitored carefully to avoid undesirable side effects induced by dexmedetomidine.