• Title/Summary/Keyword: Flow-Ratio

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A Study on the Frequency of Occurrence of the Aortic Dissection using CT (CT 검사에서 대동맥박리(aortic dissection)의 발생빈도에 관한 고찰)

  • Dong, Kyung-Rae;Choi, Sung-Kwan;Jang, Young-Ill;Ro, Sang-Ho
    • Journal of radiological science and technology
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    • v.31 no.2
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    • pp.115-121
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    • 2008
  • Purpose: Aortic Dissection is very dangerous, prognostic disease, which the bloodstream flow out of the true lumen of the aorta by the bursting of aortic intima resulting in a rapid dissociation of inner and outer layer from the media. It is difficult to diagnose aortic dissection clinically by normal X-ray. This study was to investigate the occurrence frequency by age and number of patients who are identified to be aortic dissection by CT (Computed Tomography) scan. Materials and methods: We investigated the trend of yearly fluctuation, gender, age, and department of clinical research of the 112 patients who conducted CT scan in C- University Hospital for two years from January 2005 to December 2006. The MIP and SSD which reconstructed CT image and the VRT image were obtained for the accurate observation. The result was investigated by comparing normal X-ray and CT scan. Results and Conclusion: 1. The yearly check of 112 patients conducted CT scan showed 37 people (41.9%) in 2005, and it was increased to 65 (58.1%) in 2006 by 1.4 times. 2. The gender distribution of patients given a CT scan showed 45 males (40.1%), and female 67 (59.9 %). The aortic dissection patients were 9 (20%) out of 45 males, 21 (31.3%) out of 67 females and women were 1.6 times more than men. Women are also 1.5 times more than men in the number of examinee. 3. The age distribution of patient's who conducted CT scan revealed that there was no patient under 30 years old while 88.3% of all patients were through 41 to 80 years old. The higher the age was, the higher the occurrence of aortic dissection was. The difference in the occurrence frequency of age was statistically significant (p<0.01). 4. The departments that requested CT scan were the emergency department 46 (41.1%), circulatory internal medicine 37 (33.0%), chest surgery 13 (11.6%), and others 6 (14.3%). The combined ratio of emergency medicine and circulatory internal medicine was 74.1% of all. The results show that the aortic dissection is a very dangerous disease whose patients visit mainly via the emergency room. 5. The aortic dissection patients had normal X-ray readings in 22 (73.3%) out of 30, and only 8 (26.7 percent) are abnormal in the X-ray diagnosis. Therefore, the CT scan needs to be enforced in order to assess accurately the disease of aortic dissection.

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A Study on Air Resistance and Greenhouse Gas Emissions of an Ocean Leisure Planning Boat (해양레저용 활주형선의 공기저항 및 온실 가스 배출에 대한 연구)

  • Kim, Y.S.;Hwang, S.K.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.16 no.3
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    • pp.202-210
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    • 2013
  • As incomes increase, interest in ocean leisure picks up. As a result, a lot of research and developments on hull form design and production of planing boats, mostly used for ocean leisure, are needed. Analysis in researches on resistance of planing boats shows that resistance characteristic of planing boats is different from resistance characteristic of general boats because the former is fast, and its wetted surface is very small. Using Savitsky formula widely used in the calculation of effective horse power in shipbuildingyards, and propulsion system and engine manufacturers, this study calculated total resistance of a research planing boat. Then it analyzed the flow characteristics of the planing boat through theoretical analysis and wind tunnel experiment, and computed air resistance and lift force by changes of speed and trim angle. It also compared and analyzed result of theoretical analysis and experiment of the ratio of air resistance to total resistance under variations of velocity and trim angle. When the study is used to estimate more accurate effective horse power, it is expected to remedy abuses of unnecessarily installing high-powered engine. As nature disasters due to abnormal changes of weather increase, interest in greenhouse gas grows. International Maritime Organization (IMO) legislated Energy Efficiency Design Index (EEDI) and Energy Efficiency Operational Indicator (EEOI) to reduce ship greenhouse gas emissions. But this index will be applied to over 400 tons ships, small ships, emitting more greenhouse gases than larege ships per unit power, will dodge the regulations. Thus, this study indicated a problem by calculating greenhouse gas emissions of an ocean leisure planning boat (a small ship), and suggested the need for EEDI of small ships.

Feasibility Test of Biohydrogen Production from Food Waste (음식물쓰레기의 수소발효 타당성 평가)

  • Han, Sun-Kee;Kim, Sang-Hyoun;Shin, Hang-Sik
    • Journal of the Korea Organic Resources Recycling Association
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    • v.11 no.3
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    • pp.87-95
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    • 2003
  • Although extensive studies were conduced on hydrogen fermentation of organic wastewaters, little is known about biohydrogen production from organic solid wastes. The leaching-bed reactor treating food waste by heat-shocked anaerobic sludge was, therefore, operated at D of 2.1, 3.6, 4.5 and $5.5d^{-1}$ to find optimal D for hydrogen production. Successful operation of a reactor can be accomplished when it is operated at proper dilution rate (D). Operation at high D leads to the washout of biomass in the reactor while operation at low D leads to product inhibition due to the accumulation of excess VFA. These appear to limit the production of hydrogen to reach a higher level. All the reactors showed that, on day 1-3, hydrogen production was dominant and VFA concentration was higher than ethanol. Butyrate and acetate were major components of VFAs over the whole operation, though lactate was very high on day 1-2. Compared with other D values, D of $4.5d^{-1}$, resulted in higher butyrate/acetae (B/A) ratios during the fermentation. The trend of B/A ratios was similar to the hydrogen production, suggesting that butyrate formation favored hydrogen production. Ethanol increased significantly from day 4 when hydrogen Production stopped. It indicated that heat-shocked sludge was able to induce a metabolic flow from hydrogen-and acid-producing pathway to solvent-producing pathway. Operation at D of $4.5d^{-1}$ led to higher fermentation efficiency (58%) than those (51.5, 55.3 and 53.7%) at 2.1, 3.6 and $5.5d^{-1}$. The COD removed was convened to hydrogen (10.1%), VFA (30.9%), and ethanol (17.0%).

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Impact of Allogenic and Autologous Transfusion on Immune Function in Patients with Tumors

  • Guo, Jian-Rong;Xu, Feng;Jin, Xiao-Ju;Shen, Hua-Chun;Liu, Yang;Zhang, Yi-Wei;Shao, Yi
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.467-474
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    • 2014
  • Objective: To observe the effects of allogeneic and autologous transfusion on cellular immunity, humoral immunity and secretion of serum inflammatory factors and perforin during the perioperative period in patients with malignant tumors. Methods: A total of 80 patients (age: 38-69 years; body weight: 40-78 kg; ASA I - II) receiving radical operation for gastro-intestinal cancer under general anesthesia were selected. All the patients were divided into four groups based on the methods of infusion and blood transfusion: blank control group (Group C), allogeneic transfusion group (group A), hemodiluted autotransfusion Group (Group H) and hemodiluted autotransfusion + allogenic transfusion Group (A+H group). Venous blood was collected when entering into the surgery room ($T_0$), immediately after surgery ($T_1$) and 24h ($T_2$), 3d ($T_3$) and 7d ($T_4$) after surgery, respectively. Moreover, flow cytometry was applied to assess changes of peripheral blood T cell subpopulations and NK cells. Enzyme linked immunosorbent assays were performed to determine levels of IL-2, IL-10, TNF-${\alpha}$ and perforin. Immune turbidimetry was employed to determine the changes in serum immunoglobulin. Results: Both CD3+ and NK cells showed a decrease at $T_1$ and $T_2$ in each group, among which, in group A, CD3+ decreased significantly at $T_2$ (P<0.05) compared with other groups, and CD3+ and NK cell reduced obviously only in group A at $T_3$ and $T_4$ (P<0.05). CD4+ cells and the ratio of D4+/CD8+ were decreased in groups A, C and A+H at $T_1$ and $T_2$ (P<0.05). No significant intra- and inter-group differences were observed in CD8+ of the four groups (P<0.05). IL-2 declined in group C at $T_1$ and $T_2$ (P<0.05) and showed a decrease in group A at each time point (P<0.05). Moreover, IL-2 decreased in group A + H only at $T_1$. No significant difference was found in each group at $T_1$ (P<0.05). More significant decrease in group ?? at $T_2$, $T_3$ and $T_4$ compared with group A (P<0.05), and there were no significant differences among other groups (P>0.05). IL-10 increased at $T_1$ and $T_2$ in each group (P<0.05), in which it had an obvious increase in group A, and increase of IL-10 occurred only in group A at $T_3$ and $T_4$ (P<0.05). TNF-${\alpha}$ level rose at $T_1$ (P<0.05), no inter- and intra-group difference was found in perforin in all groups (P<0.05). Compared with the preoperation, both IgG and IgA level decreased at $T_1$ in each group (P<0.05), and they declined only in Group A at $T_2$ and $T_3$ (P<0.05), and these parameters were back to the preoperative levels in other groups. No significant differences were observed between preoperative and postoperative IgG and IgA levels in each group at $T_4$ (P>0.05). No obvious inter- and intra-group changes were found in IgM in the four groups (P>0.05). Conclusions: Allogeneic transfusion during the perioperative period could obviously decrease the number of T cell subpopulations and NK cells and the secretion of stimulating cytokines and increase the secretion of inhibiting cytokines in patients with malignant tumors, thus causing a Th1/Th2 imbalance and transient decreasing in the content of plasma immune globulin. Autologous transfusion has little impact and may even bring about some improvement oo postoperative immune function in patients with tumors. Therefore, cancer patients should receive active autologous transfusion during the perioperative period in place of allogeneic transfusion.

Cell Protective Effects of Enzymatic Hydrolysates of Citrus Peel Pectin (귤피 펙틴 유래 효소적 가수분해물의 세포 보호 효과)

  • Kwon, Soon Woo;Ko, Hyun Ju;Bae, Jun Tae;Kim, Jin Hwa;Lee, Geun Soo;Pyo, Hyeong Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.1
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    • pp.75-85
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    • 2016
  • Pectin, a naturally occurring polysaccharide, has in recent years attracted considerable attention. Its benefits are increasingly appreciated by scientists and consumers due to its safety and usefulness. The chemistry and gel-forming characteristics of pectin have enabled to be used in pharmaceutical industry, health promotion and treatment. Yet, it has been rarely used in cosmetics because of its incompatibility with many cosmetic ingredients, including alcohols, and unstable viscosity of pectin gels under various pH and salt conditions. However, low-molecular-weight pectin oligomers have excellent biological activities, and depolymerization of pectin to produce cosmetic ingredients would be very useful. In this study, we attempted the development of cosmetic ingredients using pectin with an excellent effect on human skin. We developed a bio-conversion process that uses enzymatic hydrolysis to produce pectin hydrolysates containing mainly low-molecular-weight pectin oligomers. Gel permeation chromatography was used to determined the ratio of hydrolysis. The molecular weight of the pectin hydrolysates obtained varied between 200 and 2,700 Da. The two newly developed low-molecular-weight pectin hydrolysates, LMPH A and B, had higher anti-oxidative activities than pectin or D-galacturonic. Exposure to UVB radiation induces apoptotic cell death in epidermal cells. Annexin V binding and propidium iodide uptake were measured by flow cytometry to evaluate UVB-induced cell death in HaCaT cells. Both LMPH A and B reduced UVB-induced cell death and increased cell proliferation by 22% and 30% at 0.5% concentration respectively, while pectin had no significant activity. In conclusion, this study suggests that the newly developed low-molecular-weight pectin hydrolysates can be used as safe and biologically active cosmetic ingredients.

Geoscientific land management planning in salt-affected areas* (염기화된 지역에서의 지구과학적 토지 관리 계획)

  • Abbott, Simon;Chadwick, David;Street, Greg
    • Geophysics and Geophysical Exploration
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    • v.10 no.1
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    • pp.98-109
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    • 2007
  • Over the last twenty years, farmers in Western Australia have begun to change land management practices to minimise the effects of salinity to agricultural land. A farm plan is often used as a guide to implement changes. Most plans are based on minimal data and an understanding of only surface water flow. Thus farm plans do not effectively address the processes that lead to land salinisation. A project at Broomehill in the south-west of Western Australia applied an approach using a large suite of geospatial data that measured surface and subsurface characteristics of the regolith. In addition, other data were acquired, such as information about the climate and the agricultural history. Fundamental to the approach was the collection of airborne geophysical data over the study area. This included radiometric data reflecting soils, magnetic data reflecting bedrock geology, and SALTMAP electromagnetic data reflecting regolith thickness and conductivity. When interpreted, these datasets added paddock-scale information of geology and hydrogeology to the other datasets, in order to make on-farm and in-paddock decisions relating directly to the mechanisms driving the salinising process. The location and design of surface-water management structures such as grade banks and seepage interceptor banks was significantly influenced by the information derived from the airborne geophysical data. To evaluate the effectiveness ofthis planning., one whole-farm plan has been monitored by the Department of Agriculture and the farmer since 1996. The implemented plan shows a positive cost-benefit ratio, and the farm is now in the top 5% of farms in its regional productivity benchmarking group. The main influence of the airborne geophysical data on the farm plan was on the location of earthworks and revegetation proposals. There had to be a hydrological or hydrogeological justification, based on the site-specific data, for any infrastructure proposal. This approach reduced the spatial density of proposed works compared to other farm plans not guided by site-specific hydrogeological information.

Risk Factors Analysis and Results of the Arterial Switch Operation for Transposition of the Great Arteries with Intact Ventricular Septum (심실중격결손을 동반하지 않은 대혈관전위증 환자에서 동맥 전환술의 결과 및 위험인자 분석에 관한 연구)

  • 김용진;오삼세;이정렬;노준량;서경필
    • Journal of Chest Surgery
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    • v.32 no.2
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    • pp.108-118
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    • 1999
  • Background: To evaluate the risk factor and long-term result of arterial switch operation , a retrospective study was done. Material and Method: A retrospective analysis was done to evaluate the early and long-term results on 58 patients who underwent an arterial switch operation(ASO) for transposition of the great arteries(TGA) with intact ventricular septum, between January 1988 and December 1996. Beforesurgery, 36 patients(62.1%) underwent balloon atrial septostomy, 32 patients(51.7%) received PGE1 infusion, and preparatory banding of pulmonary artery was performed on 6 patients(mean LV/RV pressure ratio 0.53$\pm$0.11). Result: The age at operation ranged from 1 to 137 days(mean 24$\pm$26 days) and the weights ranged from 1.8 to 6.8 kg (mean 3.5$\pm$0.8 kg). There were 14 early deaths(24.1%), but of the last 24 patients operated on since 1994, there were only 2 early deaths(8.3%). In the risk factor analysis, the date of operation was the only risk factor for early death(p-value < 0.01). Eight of the 14 early deaths were due to acute myocardial failure(mainly inadequate coronary blood flow). The length of follow-up ranged from 2 months to 8 years, average of 36$\pm$27 months. The follow-up included sequential noninvasive evaluations and 21 catheterizations and angiographic studies performed 5 to 32 months postoperatively with particular attention to the great vessel and coronary anastomosis, ventricular function, valvular competence, and cardiac rhythm. There were 5 late deaths(11.4%), one of thesedeaths was related to the late coronary problems, two to aspiration, one to uncontrolled chronic mediastinitis, and one to progressive aortic insufficiency and heart failure. The most frequent postoperative hemodynamic abnormality was supravalvular stenosis and the degree of pulmonary or aortic obstruction had slowly progressed in some cases, however there were no children who had to undergo a reoperation for supravalvular pulmonary or aortic stenosis. Aortic regurgitation was identified in 9 patients, which was mild in 7 and moderate in 2 and had progressed in some cases. Two patients who had an unremarkable perioperative course were identified as having coronary artery obstructions. The other late survivors were in good condition, were in sinus rhythm, and had normal LV functions. Actuarial survival rate at 8 years was 68.8%. Conclusion: We concluded that anatomic correction will be established as the optimal approach to the TGA with intact ventricular septum, though further long-term evaluations are needed.

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Evaluation of short-term cardiac function by tissue Doppler imaging in pre and postoperative period of congenital heart disease (조직 도플러 영상을 이용한 선천성 심장병 수술 전후의 단기 심기능 평가)

  • Lee, Jun-Hwa;Kim, Yeo-Hyang;Hyun, Myung-Chul;Lee, Sang-Bum
    • Clinical and Experimental Pediatrics
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    • v.50 no.5
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    • pp.476-483
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    • 2007
  • Purpose : The objective of this study was to assess ventricular function by tissue Doppler imaging (TDI) in children with congenital heart disease (CHD) who have been undergoing open heart surgery (OHS) using cardiopulmonary bypass. We tried to compare the parameters of tissue Doppler imaging before and after OHS in patients with congenital heart disease. Methods : This study was conducted on 32 patients with CHD after OHS from January 2005 to December 2005 at Kyungpook National University hospital. Patients who underwent 2-D echocardiography before and after their OHS. All patients were divided into three groups, left ventricular volume overloading group (group 1), and right ventricular volume overloading group (group 2), and right ventricular pressure overloading group (group 3). The TDIs were examined before and 1 to 3 months after OHS. Peak early diastolic (E), and peak late diastolic (A) velocity of transmitral flow were measured by pulsed wave Doppler examination. Peak systolic (Sm), peak early diastolic (Em), and peak late diastolic (Am) velocity in apical 4-chamber and 2-chamber views were measured by TDI. The author calculated E/Em ratio. Results : The patients were 14 boys and 18 girls and the average age of patients was 2 years and 3 months. The congenital heart diseases which have to get OHS were ventricular septal defect (13 cases), atrial septal defect (7), atrioventricular septal defect (3), isolated pulmonary stenosis (2) and tetralogy of Fallot (7). There were significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view (P<0.05). Conclusion : This study showed significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view after OHS. These changes might be due to the effects of cardiopulmonary bypass in OHS and/or hemodynamic changes after correction of congenital heart disease. To clarify these changes, further study on more patients is needed.

Relationship between Distribution of the Dominant Phytoplankton Species and Water Temperature in the Nakdong River, Korea (낙동강의 식물플랑크톤 우점종의 분포특성 및 수온과의 상관성)

  • Yu, Jae Jeong;Lee, Hye Jin;Lee, Kyung Lak;Lyu, Heuy Seong;Whang, Jeong Wha;Shin, La Young;Chen, Se Uk
    • Korean Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.247-257
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    • 2014
  • The construction of eight large weirs in the Nakdong River, Korea, caused a decrease in the water flow velocity and several physical changes to the water environment. Here, changes in phyto- and zooplankton communities and water quality in the areas near the eight weirs were investigated from 2011 to 2013, and relationships between phytoplankton abundances and environmental factors were analyzed. Special emphasis was given to the succession patterns in algal abundance based on temperature fluctuations. At the eight weirs, 24 dominant species were found. The most abundant phytoplankton species was Stephanodiscus sp. (39.4% of dominant frequency). Cyanobacteria of the genus Microcystis dominated during the summer, with an dominant frequency of 8.5% and cell abundance ratio of 36.6%. Significant correlations were observed between temperature and abundance of eight of the main dominant species; seven species showed positive correlations with temperature. Stephanodiscus sp., however, showed a negative correlation with temperature (r=-0.26, p<0.01). In addition, this species showed a significant negative correlation with the dominant algal species-Aulacoseira granulata and Aphanizomenon flos-aquae, with the zooplankton Copepoda and with Cladocera. On the contrary, seven other dominant species of algae showed significant positive correlations with zooplankton. Thus, we showed that the seasonal succession of plankton communities in the Nakdong River was related to the water temperature changes.

Effects of Various Proteins on the Autoxidation of L-Ascorbic Acid (비타민 C 산화반응에 대한 단백질의 공존효과)

  • Kim Mi-Ok;Jang Sang-Moon
    • The Korean Journal of Food And Nutrition
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    • v.17 no.3
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    • pp.294-301
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    • 2004
  • Effects of superoxide dismutase(SOD), catalase(CAT), and such other proteins as bovine serum albumin(BSA), ovalbumin, lysozyme, and v-globulin on the autoxidation rates of L-ascorbic acid(AsA) in the absence of heavy metal ions and in the presence of Fe(III) or Cu(II) ions in water were examined. AsA was dissolved in a ultra-refined water at a concentration of 50 ${\mu}$M and 5 ${\mu}$M Fe(III) or 0.1 ${\mu}$M Cu(II) were added, and a oxygen gas was bubbled through the solution at a flow rate of 200 ml/min at 35$^{\circ}C$. The amount of remaining AsA in the reaction mixture was determined by using a UV spectrophotometer(at 265 nm). It was found that the Cu(II) at a concentration of 0.1 ${\mu}$M had a more accelerated for the autoxidation of AsA than Fe(III) at 5 ${\mu}$M. Moreover, it was confirmed that the ratio of remaining AsA was significantly larger in the presence of SOD, CAT, BSA, ovalbumin, lysozyme, and v-globulin than in the absence of proteins. The stabilization of AsA by various proteins were confirmed during the autoxidation of AsA in the presence of Fe(III) or Cu(II) in water. It was suggested that the non-enzymatic effects of SOD, CAT and some other proteins might be involves in the stabilization of AsA.