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Sample records for bypass vessels influence

  1. Factors influencing early results of femoro-femoral crossover bypass

    Directory of Open Access Journals (Sweden)

    Đorić Predrag

    2011-01-01

    Full Text Available Introduction. Femoro-femoral crossover bypass is an extraanatomic reconstruction used for revascularization of lower limb with contralatateral femoral artery as an inflow vessel, and the graft placed in the suprapubic region. We perform this procedure when anatomic reconstruction is not possible or is contraindicated. Objective. To analyze the influence of different risk factors on early patency of femoro-femoral crossover bypass. Methods. This retrospective study analyzed the results of 88 femoro-femoral bypass grafting during an 11-year period. There were 66 (75% males and 22 (25% females of average age 64.93 years (42-79 years. In 76 patients the operations were performed due to critical limb ischemia. Revascularization was urgent in 12 patients, while 76 patients were elective. Dacron prosthesis was used in 81 patients, while PTFE was used in 7 patients. Statistical analysis was made by logistic regression. Results. During hospitalisation the graft remained patent in 82 patients, and graft thrombosis occurred in 6 patients. Limb salvage rate was 90.91%. Early morbidity rate (within the first post-operative month was 13.64%, while early mortality rate was 4.55%. Using logistic regression we established that early graft patency was statistically more significant in males (p<0.05. Age (p=0.07 and hypertension (p=0.08 appeared to be predicting influence of the graft patency on the border of the accepted statistical significance level. Conclusion. Femoro-femoral crossover bypass is a good alternative for revascularization in high risk patients for standard anatomic reconstructions due to comorbid conditions or local problems.

  2. Graft patency in off-pump and conventional coronary artery bypass grafting for treatment of triple vessel coronary disease

    Institute of Scientific and Technical Information of China (English)

    胡盛寿; 王小启; 宋云虎; 吕锋

    2003-01-01

    Objective To compare graft patency in off-pump and conventional coronary artery bypass grafting by using the transit time flow meter in the treatment of triple vessel coronary artery disease. Methods Between June 2000 and April 2001, 60 patients with triple vessel coronary artery disease underwent coronary artery bypass grafting. They were divided into two groups: off-pump and conventional coronary artery bypass. All completed grafts were tested intraoperatively using Transit Time Flow Measurement (TTFM). Preoperative and postoperative variables of the two groups were also compared. Results There were no significant differences in sex, age, weight, acute or remote myocardial infarction, hypertension, diabetes and type of bypass grafts between the two groups. The number of bypass grafts and the assisted respiratory time of the off-pump coronary artery bypass grafting (OPCAB) group were significantly less than those of the conventional coronary artery bypass grafting (CCABG) group. The flow and pulsatile index (PI) of the left anterior descending artery bypass grafts and the right coronary artery bypass grafts were not significantly different between the OPCAB and CCABG groups. The flow of OM in the CCABG group with the multiple anastomosis site of sequential grafts was higher than that in the OPCAB group. Diffused narrow coronary artery bypass grafts in both groups had less flow.Conclusion No signficant differences in graft patency were observed in patients with triple vessel coronary artery disease who had undergone OPCAB or CCABG.

  3. Simulation and Analysis of the bypass Influences on Tire Noise

    Directory of Open Access Journals (Sweden)

    Haichao Zhou

    2014-01-01

    Full Text Available It is a well-known scientific fact that circumferential groove exists great influence on tire noise. Increasing the void can help the rubber blocks to penetrate faster into the underlying water film and improve anti-skid performance, but which gives way to an increased air pumping noise. Therefore, the structure parameters of circumferential grooves play large influence on tire performance. The goal of this present study is using the bypass to change the grooves design and analysis the influence of bypass on tire noise and offer the tire designer a better approach to improve tire comfort ability. By virtual of numerical simulation method, the influence of bypass structure parameters, such as the width of junction pipe, the volume of resonance cavity, on tire noise were analyzed in this study. The result shows that the circumferential grooves with bypass not only bring down pipe resonance noise of circumferential grooves but also decrease far-field radiated noise of tire. Besides, with a certain resonant cavity, the width of junction pipeline between the circumferential grooves and the resonance cavity plays an important role in the improvement of tire noise. Simulation results are in reasonable agreement with experimental results.

  4. Simulation and Analysis of the bypass Influences on Tire Noise

    OpenAIRE

    Haichao Zhou; Guolin Wang; Jian Yang; Shizhou Ying

    2014-01-01

    It is a well-known scientific fact that circumferential groove exists great influence on tire noise. Increasing the void can help the rubber blocks to penetrate faster into the underlying water film and improve anti-skid performance, but which gives way to an increased air pumping noise. Therefore, the structure parameters of circumferential grooves play large influence on tire performance. The goal of this present study is using the bypass to change the grooves design and analysis the influe...

  5. Five Vessel Coronary Arter Bypass Graft Surgery in a Case with Familial Hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Sureyya Talay

    2014-08-01

    Full Text Available We report a case of a rare and sypmtomatic familyal hypercholesterolemia case with an end-point of coronary artery bypass surgery at the age of 16. Patient was evaluated at the emergency department with chest pain and discomfort. Physical examination were within normal limits. The electrocardiogram showed a normal sinus rhythm for 108/ min. Arterial blood pressure was 90/60 mmHg. Lungs and heart were clear to auscultation. Patient was under treatment with a prior diagnosis of familial hypercholesterolemia (FH for one year by daily 40 mgs rosuvastatine. A coronary artery angiography was performed for chest pain. Multivessel coronary artery disease was diagnosed with a total occlusion of left anterior descending artery. Transthoracic echocardiography presented a left ventricular (LV ejection fraction 50%, LV diameters 44/26 mm, aneurysm formation at interatrial septum and mild dyskinesia of anterior wall. Thus, a five vessel emergent coronary artery graft bypass surgery was performed at this early age. FH is with a severe elevation in total cholesterol (TC and low density lipoprotein cholesterol (LDL in an autosomal dominant characteristic disorder that approximately occurs in 1 per 500 persons by its heterozygous form. FH is most certainly associated with premature coronary artery disease (CAD with catasthrophic early age results. [Cukurova Med J 2014; 39(4.000: 872-875

  6. The influence of core bypass flow during SBLOCA

    International Nuclear Information System (INIS)

    Many parameters affect the behaviour of a NPP during a Small Break Loss of Coolant Accident (SBLOCA). The bypass flow between the core side and the downcomer is one of them. Different PWRs have different values of core bypass flow. In spite of the complexity of the real situation in the primary system during SBLOCA, some fundamental details of the phenomena can be explained with simplified mathematical models, which relate on basic parameters of the primary coolant. These models define the conditions for loop seal clearance and final results are confirmed with measured values. The analysis presented in the paper refers to Bethsy Test 9.1.b SB LOCA scenario, with variation of core bypass flow. Basic RELAP5 input model calculation results show very good agreement with the experimental data. The core liquid level depression before loop seal clearance is lower in case of smaller core bypass flow. This affects the fuel clad temperature because of different heat transfer mechanisms. Time of loop seal clearance is delayed with larger core bypass flow and consequently lower differential pressure between downcomer and core. (author)

  7. Comparison of Treatment Outcomes in Off-pump Coronary Artery Bypass Graft and Medical Therapy in Patients with Triple-vessel Coronary Artery Disease and Severe Ventricular Dysfunction

    OpenAIRE

    Feridoun Sabzi; Hossein Karim; Shahrokh Chaghazardi; Atefeh Asadmobini

    2016-01-01

    Introduction: Heart failure is a major hazard for public health. Despite recent advance in medical therapy, there is not enough information on the outcome of off-pump coronary artery bypass (OPCAB) and medical therapy on the patients with severe ventricular dysfunction and triple-vessel (CAD). This study aimed to compare treatment outcomes and mortality rate in patients undergoing off-pump coronary artery bypass (OPCAB) surgery and medical therapy who presented with severe ventricular dysfunc...

  8. The influence of stenosis degrees and graft suture position on local hemodynamics of coronary bypass

    Science.gov (United States)

    Totorean, A. F.; Bernad, S. I.; Susan-Resiga, R. F.

    2016-06-01

    Bypass graft failure is mainly caused by intimal hyperplasia (IH) that occurs at the graft anastomosis after coronary artery bypass grafting (CABG) surgery. It has been shown that local hemodynamics influences the process of IH initiation and progression. A main concern at this type of surgery is to increase the graft patency, respectively to improve the local hemodynamics. This paper analyzes the influence of different degree of stenosis severity and graft suture position on graft patency, taking into consideration the local hemodynamics. Bypass configurations with anastomosis angle of 45° were numerically investigated, with respect to wall shear stress and pressure variation. We can assume that in the conditions of our study, different stenosis degrees and position of the graft suture influence the local blood flow conditions, and, nevertheless, the graft patency.

  9. Clinical Outcomes After Drug-Eluting Stents Versus Coronary Artery Bypass Surgery in High Surgical Risk Patients With Left Main or Three-Vessel Coronary Artery Disease

    OpenAIRE

    Tonga Nfor; Kambiz Shetabi; Wael Hassan; Quinta Nfor; Jayant Khitha; Anjan Gupta; Tanvir Bajwa; Suhail Allaqaband

    2015-01-01

    Purpose: Previous studies comparing percutaneous coronary intervention (PCI) with coronary artery bypass graft surgery (CABG) in patients with unprotected left main or three-vessel coronary artery disease (LM-3VD) have excluded patients at high surgical risk. We compared clinical outcomes after PCI with drug-eluting stents to CABG in high surgical risk patients with LM-3VD. Methods: Patients with symptomatic LM-3VD who had Society of Thoracic Surgeons (STS)-predicted operative mortality >...

  10. Computer-aided analysis of bypass in direct vessel vertical injection system

    International Nuclear Information System (INIS)

    Recent advances in three-dimensional computer-aided design has rendered it practicable to lend itself to commercial computational fluid dynamics and structural mechanics finite element analysis codes to cross-communicate detailed geometric data. The main focus is placed on application of this powerful design tool in examining performance of the emergency core cooling system (ECCS) employing the direct vessel injection (DVI) in the APR1400 (Advanced Power Reactor 1400 MWe). In this work a new method of direct vessel vertical injection (DVVI) is proposed as an advanced type of DVI for the APR1400. In view of the ECCS function to efficaciously cool down the core during a loss-of-coolant accident (LOCA), for example, the concept of DVVI is geared to increasing the downward momentum of the injected water so as to maximize penetration into the downcomer versus by pass through the break. Furthermore, one needs to pay a special attention to the structural integrity of the injection nozzle on account of the radioactive primary system environment. In particular, vibration and pressure induced by the safety injection (SI) flow will tend to exert predomination forces onto the DVVI nozzles having an elbow. Therefore, in this work, focus is placed on the flow regime at the tip of the DVVI nozzle and the structural impact caused by rapid injection of the emergency core cooling (ECC) water in the APR1400. The current work consists of a three-dimensional (3D) computer-aided design (CAD) modeling using CATIA V5R9, CFX 5.5 and ANSYS 6.1 to determine the most vulnerable spot of the DVVI nozzle, and to check on the performance efficiency of DVVI during the ECC injection period. In this study it was considered that the 3D CAD model for the DVVI nozzle was submerged in a high-velocity steam. The effect of the rebounding force of the injected water has also been simulated. The 3D CAD model for the DVVI nozzle simulates its mass, texture and constitution material. In this work the DVVI

  11. Analysis of Large In-vessel First Wall Pipe Break with Wet Confinement Bypass in the ITER

    International Nuclear Information System (INIS)

    This extreme reactor condition gives the importance of safety issue. Previous researches have been analyzed risk assessments of fusion reactors that are dangerous in the severe accidents where the radioactive material released from confinement building to the environment. To simulate the severe accidents in ITER, a number of thermal hydraulics simulation codes were used. Before construction of the fusion reactor, to gain safety permission, MELCOR is chosen as one of the several codes to be used to perform ITER safety analyses. Qualification of the simulation code is to simulate the cooling system in ITER, the transport of radionuclides during design basis accidents (DBAs) including beyond design basis accidents (BDBAs). MELCOR is fully integrated code that models the accidents in Light Water Reactor (LWR). To analyze the accidents in ITER, MELCOR 1.8.2 version is modified. In the nuclear fusion system, the amount of released radioactive material is criteria for safety permission (safety permission). Tritium (or tritiated water: HTO) and radioactive dust aerosol are the source of radioactive leakage. In the Generic Site Safety Report (GSSR) for the ITER plant, Table I lists the release guidelines for tritium and activation products for normal operation, incidents and accidents. Several accident analyses have been studied to know how much radioactive material could be released from the severe accidents. In the present work, the large First Wall (FW) coolant leak (pipe break) and radioactive material leakage thorough bypass accident are studied. In this research, the in-vessel inboard/inboard-outboard FW pipe break was analyzed investigate the amount of leakage of radioactive aerosol

  12. Analysis of Large In-vessel First Wall Pipe Break with Wet Confinement Bypass in the ITER

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sung Bo; Bang, In Cheol [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-10-15

    This extreme reactor condition gives the importance of safety issue. Previous researches have been analyzed risk assessments of fusion reactors that are dangerous in the severe accidents where the radioactive material released from confinement building to the environment. To simulate the severe accidents in ITER, a number of thermal hydraulics simulation codes were used. Before construction of the fusion reactor, to gain safety permission, MELCOR is chosen as one of the several codes to be used to perform ITER safety analyses. Qualification of the simulation code is to simulate the cooling system in ITER, the transport of radionuclides during design basis accidents (DBAs) including beyond design basis accidents (BDBAs). MELCOR is fully integrated code that models the accidents in Light Water Reactor (LWR). To analyze the accidents in ITER, MELCOR 1.8.2 version is modified. In the nuclear fusion system, the amount of released radioactive material is criteria for safety permission (safety permission). Tritium (or tritiated water: HTO) and radioactive dust aerosol are the source of radioactive leakage. In the Generic Site Safety Report (GSSR) for the ITER plant, Table I lists the release guidelines for tritium and activation products for normal operation, incidents and accidents. Several accident analyses have been studied to know how much radioactive material could be released from the severe accidents. In the present work, the large First Wall (FW) coolant leak (pipe break) and radioactive material leakage thorough bypass accident are studied. In this research, the in-vessel inboard/inboard-outboard FW pipe break was analyzed investigate the amount of leakage of radioactive aerosol.

  13. Follow-up Study of ITER Safety Analysis : Large In-vessel First Wall Pipe Break with Wet Confinement Bypass

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sung Bo; Bang, In Cheol [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-10-15

    Previous researches have been analyzed risk assessments of fusion reactors that are dangerous in the severe accidents where the radioactive material released from confinement building to the environment. To simulate the severe accidents in ITER, a number of thermal hydraulics simulation codes were used. Before construction of the fusion reactor, to obtain ITER license about safety issue, MELCOR is chosen as one of the several codes to be used to perform ITER safety analyses. Qualification of the simulation code is to simulate the cooling system in ITER, the transport of radionuclides during design basis accidents (DBAs) including beyond design basis accidents (BDBAs). MELCOR is fully integrated code that models the accidents in Light Water Reactor (LWR). To analyze the accidents in ITER, MELCOR 1.8.2 version is modified. In the nuclear fusion system, the amount of released radioactive material is criteria for safety permission. Tritium (or tritiated water: HTO) and radioactive dust aerosol are the source of radioactive leakage. In the Generic Site Safety Report (GSSR) for the ITER plant, Table I lists the release guidelines for tritium and activation products for normal operation, incidents and accidents. Several accident analyses have been studied to know how much radioactive material could be released from the severe accidents. In the present work, The MELCOR input deck of large First Wall (FW) coolant leak (pipe break) is used to study and radioactive material leakage thorough bypass accident are studied to follow up the ITER safety analysis. In this research, follow-up study of the in-vessel inboard/inboard-outboard FW pipe break was analyzed to investigate the amount of leakage of radioactive aerosol. All of the accident cases released the lower amount of radioactive aerosol compared to the IAEA guide lines. In addition, the OBB pipe break made lower HTO aerosol leakage because of condensation of HTO and adsorption between coolant and aerosol.

  14. Follow-up Study of ITER Safety Analysis : Large In-vessel First Wall Pipe Break with Wet Confinement Bypass

    International Nuclear Information System (INIS)

    Previous researches have been analyzed risk assessments of fusion reactors that are dangerous in the severe accidents where the radioactive material released from confinement building to the environment. To simulate the severe accidents in ITER, a number of thermal hydraulics simulation codes were used. Before construction of the fusion reactor, to obtain ITER license about safety issue, MELCOR is chosen as one of the several codes to be used to perform ITER safety analyses. Qualification of the simulation code is to simulate the cooling system in ITER, the transport of radionuclides during design basis accidents (DBAs) including beyond design basis accidents (BDBAs). MELCOR is fully integrated code that models the accidents in Light Water Reactor (LWR). To analyze the accidents in ITER, MELCOR 1.8.2 version is modified. In the nuclear fusion system, the amount of released radioactive material is criteria for safety permission. Tritium (or tritiated water: HTO) and radioactive dust aerosol are the source of radioactive leakage. In the Generic Site Safety Report (GSSR) for the ITER plant, Table I lists the release guidelines for tritium and activation products for normal operation, incidents and accidents. Several accident analyses have been studied to know how much radioactive material could be released from the severe accidents. In the present work, The MELCOR input deck of large First Wall (FW) coolant leak (pipe break) is used to study and radioactive material leakage thorough bypass accident are studied to follow up the ITER safety analysis. In this research, follow-up study of the in-vessel inboard/inboard-outboard FW pipe break was analyzed to investigate the amount of leakage of radioactive aerosol. All of the accident cases released the lower amount of radioactive aerosol compared to the IAEA guide lines. In addition, the OBB pipe break made lower HTO aerosol leakage because of condensation of HTO and adsorption between coolant and aerosol

  15. Predicting target vessel location on robot-assisted coronary artery bypass graft using CT to ultrasound registration

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Daniel S.; Linte, Cristian; Chen, Elvis C. S.; Bainbridge, Daniel; Wedlake, Chris; Moore, John; Barron, John; Patel, Rajni; Peters, Terry [Imaging Research Laboratories, Robarts Research Institute and Biomedical Engineering Graduate Program, University of Western Ontario, Ontario N6A 5K8 (Canada); Imaging Research Laboratories, Robarts Research Institute and Biomedical Imaging Resource, Mayo Clinic, Rochester, Minnesota 55905 (United States); Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, Ontario N6A 5K8 (Canada); Canadian Surgical Technologies and Advanced Robotics, London, Ontario N6A 5A5 (Canada); Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, Ontario N6A 5K8 (Canada); Department of Computer Science, University of Western Ontario, Ontario N6A 5B7 (Canada); Canadian Surgical Technologies and Advanced Robotics, London, Ontario N6A 5A5 (Canada); Imaging Research Laboratories, Robarts Research Institute, Biomedical Engineering Graduate Program, University of Western Ontario N6A 5K8 (Canada); and Canadian Surgical Technologies and Advanced Robotics, London, Ontario N6A 5A5 (Canada)

    2012-03-15

    Purpose: Although robot-assisted coronary artery bypass grafting (RA-CABG) has gained more acceptance worldwide, its success still depends on the surgeon's experience and expertise, and the conversion rate to full sternotomy is in the order of 15%-25%. One of the reasons for conversion is poor pre-operative planning, which is based solely on pre-operative computed tomography (CT) images. In this paper, the authors propose a technique to estimate the global peri-operative displacement of the heart and to predict the intra-operative target vessel location, validated via both an in vitro and a clinical study. Methods: As the peri-operative heart migration during RA-CABG has never been reported in the literatures, a simple in vitro validation study was conducted using a heart phantom. To mimic the clinical workflow, a pre-operative CT as well as peri-operative ultrasound images at three different stages in the procedure (Stage{sub 0}--following intubation; Stage{sub 1}--following lung deflation; and Stage{sub 2}--following thoracic insufflation) were acquired during the experiment. Following image acquisition, a rigid-body registration using iterative closest point algorithm with the robust estimator was employed to map the pre-operative stage to each of the peri-operative ones, to estimate the heart migration and predict the peri-operative target vessel location. Moreover, a clinical validation of this technique was conducted using offline patient data, where a Monte Carlo simulation was used to overcome the limitations arising due to the invisibility of the target vessel in the peri-operative ultrasound images. Results: For the in vitro study, the computed target registration error (TRE) at Stage{sub 0}, Stage{sub 1}, and Stage{sub 2} was 2.1, 3.3, and 2.6 mm, respectively. According to the offline clinical validation study, the maximum TRE at the left anterior descending (LAD) coronary artery was 4.1 mm at Stage{sub 0}, 5.1 mm at Stage{sub 1}, and 3.4 mm at

  16. Comparative study of on-pump and off-pump coronary bypass surgery in patients with triple-vessel coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    陈鑫; 徐明; 史宏伟; 穆心伟; 陈振强; 邱志兵

    2004-01-01

    Background Studies on selected patients undergoing off-pump versus on-pump coronary artery bypass surgery have produced inconsistent results, especially in patients with multiple coronary artery disease. This study compared the clinical results of on-pump and off-pump coronary bypass surgery in patients with triple-vessel disease.Methods A total of 300 consecutive isolated, multiple coronary artery bypass grafting (CABG) patients were assigned to the off-pump coronary artery bypass (OPCAB, n=150) or CABG with cardiopulmonary bypass (CCABG, n=150) groups. There were no significant differences regarding degree of angina, history of myocardial infarction or diabetes, and presence of left main coronary artery disease between the two groups. Ejection fraction in the OPCAB group before surgery was lower than in the CCABG group (P<0.01). In addition, more patients had a history of stroke and abnormal renal function preoperatively in the OPCAB group(P< 0.01). In OPCAB patients, single deep pericardial stay suture with a sling snared down was used to expose the target vessels, along with a stabilizer and a coronary shunt. A Medi-Stim Butterfly Flowmeter was used to measure blood flow through grafts in both groups.Results No OPCAB patient was converted to the CCABG group. The average numbers of distal anastomoses and the indexes of completeness of revascularization (ICR) were similar in both groups. Postoperative respiratory support time and the volumes of chest tube drainage and of blood transfusions were less in the OPCAB group than in the CCABG group (both P<0.01). The postoperative incidences of pulmonary dysfunction and renal insufficiency were lower in the OPCAB group than in the CCABG group (both P<0.05). There were no significant differences between the two groups in mortality and other causes of morbidity (periopetative myocardial infarction, stroke, atrial fibrillation). Conclusions OPCAB can be applied to patients with triple-vessel coronary artery disease and can

  17. Evaluation of Factors Influencing Liver Function Test in On-Pump Coronary Artery Bypass Graft Surgery

    Directory of Open Access Journals (Sweden)

    Shahrbano Shahbazi

    2013-12-01

    Full Text Available Background: Liver dysfunction during on-pump coronary artery bypass graft surgery (CABG is a rare complication but is associated with significant morbidity and mortality. The ability to identify high-risk patients may be helpful in planning appropriate management strategies. We aimed to evaluate the factors influencing liver function tests during on-pump CABG. Methods: In 146 patients scheduled for on-pump CABG, the liver function test was done preoperatively and on the first postoperative day. Some preoperative and intraoperative risk factors were checked and then the postoperative liver function tests were compared with the preoperative ones. Probable relationships between these changes and the preoperative and intraoperative risk factors were studied. Results: A medical history of diabetes had a significant relationship with the changes in direct bilirubin. Preoperative central venous pressure had a significant relationship with the changes in aspartate aminotransferase and alanine aminotransferase. Use of intra-aortic balloon pump and duration of aortic cross-clamp were significantly related to the changes in the liver function tests except for alanine aminotransferase and alkaline phosphatase. Conclusion: It seems that the techniques for the reduction of cardiopulmonary bypass and aortic cross-clamp duration may be useful to protect liver function. We recommend that a larger population of patients be studied to confirm these findings.

  18. Radial Body Forces Influence on FGM and Non-FGM Cylindrical Pressure Vessels

    OpenAIRE

    Jacob Nagler

    2016-01-01

    This study deals with the influence of radial body forces on FGM and non-FGM pressure vessels. It contains an extended overview of pressure vessels made from both kinds of material. Furthermore, full mathematical development of stress-strain field for both kinds of cylindrical vessels while being influenced by body forces has been performed. In addition, a new power law model for FGM materials was suggested and discussed. Finally, tables of composed plastic-elastic states are discussed.

  19. Influence of matrix size, vessel shape, vascular diameter, flow velocity, course of vessels on MR angiography

    International Nuclear Information System (INIS)

    Basic experiments were done to examine the influence of the extent of curve, direction of flow, vascular diameter, velocity of flow, and course of vessels on MR angiography. In the first experiment, two phantoms were constructed of vinyl tubing, a hairpin type and one with tubes bent to varying degrees. These phantoms were imaged in two matrices, different FOV (field of view), and of various velocities with a 1.5 Tesla system. Images of a normal volunteer were also obtained. In studies of the hairpin phantoms, a low intensity artifact appeared at the curve position, and the edge became fuzzy when the flow was perpendicular to the phase encoding direction. These phenomena were more apparent with a smaller matrix, smaller FOV, more gentle angle, larger diameter, and faster flow; in other words the component along the direction was dominant. In the phantom that used bent tubes, another low intensity artifact appeared on the medial side of the out-flow portion. The results obtained from the volunteer corresponded well to those from the basic experiments. It was thought that the profile of flow was not well demonstrated due to the coarse matrix. In the second experiment, water flowed at various speeds through three-dimensional phantoms that were made of vinyl tubes of various diameters and directions. The phantoms were imaged with two- and three-dimensional time of flight and phase contrast angiography. The lower limits of detection of the phase contrast method were almost the same. In the coronal plane, the lower limit decreased to 2.5 mm for arteries and 9.5 mm for veins. Flow within the axial plane lost signal on the way, probably because of saturation. In the two-dimensional phase contrast method, there was little dependence on direction when encoded in three axes. These results were compatible with clinical results. For routine studies, the gap between slabs needs to be eliminated, and faster data processing are necessary. (author)

  20. Influence of colloid infusion on coagulation during off-pump coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    K Muralidhar

    2010-01-01

    Full Text Available This study was conducted to determine the influence of colloid infusion on coagulation in patients undergoing off-pump coronary artery bypass grafting (OP-CABG. Thirty patients undergoing elective OP-CABG received medium molecular weight hydroxyethyl starch group I (MMW-HES 200/0.5, low molecular weight hydroxyethyl starch group II (LMW-HES 130/0.4 or gelatin group III (GEL in a prospective randomized trial. Blood samples were assessed for hemoglobin (Hb, activated coagulation time (ACT, prothrombin time (PT, activated partial thromboplastin time (aPPT, platelet count, fibrinogen and von Willebrand factor (vWF at specified intervals. Total volume of the colloid infused and postoperative chest-time drainage was also measured. There was a significant decrease in Hb, platelet count, fibrinogen levels in all these groups, which did not warrant blood transfusion. After the colloid infusion, vWF decreased significantly to 67% from baseline in group I as compared to 85 and 79% in group II and group III, respectively. vWF levels remained lower than the baseline value in the first 24 hours in group I, whereas this factor level increased above the baseline values in groups II and III, 6 hours postoperatively. Postoperative chest tube drainage in 24 hours was significantly higher in group I (856 ± 131 ml as compared to group II (550 ± 124 ml and group III (582 ± 159 ml. LMW-HES 130/0.4 was superior to MMW-HES 200/0.5 and gelatin in patients undergoing OP-CABG, in terms of better preservation of coagulation associated with enhanced volume effect.

  1. On Pump versus Off Pump Coronary Artery Bypass Surgery in Patients Over Seventy Years Old with Triple Vessels Disease and Severe Left Ventricle Dysfunction: Focus on Early Clinical Outcomes

    OpenAIRE

    Seyed Jalil Mirhosseini; Seyed Khalil Forouzannia; Sadegh Ali-Hassan-Sayegh; Mehdi Hadad-Zadeh; Mohammad Hassan Abdollahi; Hossein Moshtaghiom; Habiballah Hosseini

    2013-01-01

    Cardiovascular disease is the leading reason of morbidity in older people. Coronary artery bypass graft (CABG) surgery is the most common type of operations in world. This study was designed to characterize comparison of early clinical outcome following on pump vs. off pump in patients over 70 years old with triple vessels disease and severe left ventricle dysfunction. 80 patients were divided into two groups: In group A (n=40) on pump CABG was performed with hypothermic cardiopulmonary bypas...

  2. Age and the means of bypassing stasis influence the intrinsic subtype of immortalized human mammary epithelial cells.

    Science.gov (United States)

    Lee, Jonathan K; Garbe, James C; Vrba, Lukas; Miyano, Masaru; Futscher, Bernard W; Stampfer, Martha R; LaBarge, Mark A

    2015-01-01

    Based on molecular features, breast cancers are grouped into intrinsic subtypes that have different prognoses and therapeutic response profiles. With increasing age, breast cancer incidence increases, with hormone receptor-positive and other luminal-like subtype tumors comprising a majority of cases. It is not known at what stage of tumor progression subtype specification occurs, nor how the process of aging affects the intrinsic subtype. We examined subtype markers in immortalized human mammary epithelial cell lines established following exposure of primary cultured cell strains to a two-step immortalization protocol that targets the two main barriers to immortality: stasis (stress-associated senescence) and replicative senescence. Cell lines derived from epithelial cells obtained from non-tumorous pre- and post-menopausal breast surgery tissues were compared. Additionally, comparisons were made between lines generated using two different genetic interventions to bypass stasis: transduction of either an shRNA that down-regulated p16(INK4A), or overexpressed constitutive active cyclin D1/CDK2. In all cases, the replicative senescence barrier was bypassed by transduction of c-Myc. Cells from all resulting immortal lines exhibited normal karyotypes. Immunofluorescence, flow cytometry, and gene expression analyses of lineage-specific markers were used to categorize the intrinsic subtypes of the immortalized lines. Bypassing stasis with p16 shRNA in young strains generated cell lines that were invariably basal-like, but the lines examined from older strains exhibited some luminal features such as keratin 19 and estrogen receptor expression. Overexpression of cyclin D1/CDK2 resulted in keratin 19 positive, luminal-like cell lines from both young and old strains, and the lines examined from older strains exhibited estrogen receptor expression. Thus age and the method of bypassing stasis independently influence the subtype of immortalized human mammary epithelial cells

  3. Overexpression of isocitrate lyase-glyoxylate bypass influence on metabolism in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Otero, José Manuel; Olivares Hernandez, Roberto;

    2009-01-01

    In order to improve the production of succinate and malate by the filamentous fungus Aspergillus niger the activity of the glyoxylate bypass pathway was increased by over-expression of the isocitrate lyase (icl) gene. The hypothesis was that when isocitrate lyase was up-regulated the flux towards...

  4. Nonselective digital subtraction angiography of aortocoronary bypasses

    International Nuclear Information System (INIS)

    Intra-arterial DSA was performed on 225 patients with a total of 552 coronary bypasses (515 aorto-coronary venous bypasses and 37 internal mammary artery bypasses). Four hundred and ninety-five bypasses were examined in the four weeks following surgery; of these, 428 (85.9%) were patent. Demonstration of the distal anastomosis was obtained in 40.4% of bypasses of the right anterior interventricular artery and in 36.1% of the right coronary artery, at least in their proximal parts. Bypasses of smaller branches showed filling in 12.8 to 19.2%. Because of the unsatisfactory demonstration of distal vessels by non-selective intra-arterial DSA, this method is suitable only for showing the patency of a bypass in the postoperative phase, but should not be used for investigating cardiac signs and symptoms following a bypass examination. (orig.)

  5. Intestinal adaptations in chronic kidney disease and the influence of gastric bypass surgery.

    Science.gov (United States)

    Hatch, Marguerite

    2014-09-01

    Studies have shown that compensatory adaptations in gastrointestinal oxalate transport can impact the amount of oxalate excreted by the kidney. Hyperoxaluria is a major risk factor in the formation of kidney stones, and oxalate is derived from both the diet and the liver metabolism of glyoxylate. Although the intestine generally absorbs oxalate from dietary sources and can contribute as much as 50% of urinary oxalate, enteric oxalate elimination plays a significant role when renal function is compromised. While the mechanistic basis for these changes in the direction of intestinal oxalate movements in chronic renal failure involves an upregulation of angiotensin II receptors in the large intestine, enteric secretion/excretion of oxalate can also occur by mechanisms that are independent of angiotensin II. Most notably, the commensal bacterium Oxalobacter sp. interacts with the host enterocyte and promotes the movement of oxalate from the blood into the lumen, resulting in the beneficial effect of significantly lowering urinary oxalate excretion. Changes in the passive permeability of the intestine, such as in steatorrhoea and following gastric bypass, also promote oxalate absorption and hyperoxaluria. In summary, this report highlights the two-way physiological signalling between the gut and the kidney, which may help to alleviate the consequences of certain kidney diseases. PMID:24951497

  6. Numerical analysis of bypass model geometrical parameters influence on pulsatile blood flow

    Directory of Open Access Journals (Sweden)

    Jonášová A.

    2011-06-01

    Full Text Available The present study is focused on the analysis of pulsatile blood flow in complete idealized 3D bypass models in dependence on three main geometrical parameters (stenosis degree, junction angle and diameter ratio. Assuming the blood to be an incompressible Newtonian fluid, the non-linear system of Navier-Stokes equations is integrated in time by a fully implicit second-order accurate fractional-step method. The space discretization is performed with the help of the cell-centred finite volume method formulated for unstructured tetrahedral grids. In order to model a realistic coronary blood flow, a time-dependent flow rate taken from corresponding literature is considered. For the analysis of obtained numerical results, special emphasis is placed on their comparison in the form of velocity isolines at several selected cross-sections during systolic and diastolic phases. The remainder of this paper is devoted to discussion of walls shear stress distribution and its oscillatory character described by the oscillatory shear index with regard to areas prone to development of intimal hyperplasia or to thrombus formation.

  7. Multivariate Analysis of Factors Influencing Length of Hospital Stay after Coronary Artery Bypass Surgery in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Amin Torabipour

    2016-03-01

    Full Text Available Length of hospital stay (LOS is a key indicator for hospital management. Reducing hospital stay is a priority for all health systems. We aimed to determine the length of hospital stay following Coronary Artery Bypass Surgery (CABG based on its clinical and non-clinical factors. A cross-sectional study of 649 consecutive patients who underwent coronary artery bypass graft surgery was conducted in Imam Khomeini and Shariati university hospitals, Tehran, Iran. Data was analyzed by using non-parametric univariate tests and multiple linier regression models. Thirty seven independent variables including pre-operative, intra-operative and post-operative variables were analyzed. Finally, an appropriate model was constructed based on the associated factors. The results showed that 70.3% of the patients were male, and the mean age of the patients was 59.3 ± 10.4 years. The Mean (±SD and median of the LOS were 11.7 ± 7.1 and 9 days, respectively. Of 37 investigated variables, 24 qualitative and quantitative variables were significantly associated with length of stay (p<0.05. Multiple linear regression analysis showed that independent variables including age, medical insurance type, body mass index, and prior myocardial infarction; admission day, admission season, Cross-clamp time, pump usage, admission type, the number of laboratory tests and the number of specialty consultation had more effect on the hospital stay. We concluded that some significant factors influencing hospital stay after CABG were predictable and modifiable by hospital managers and decision makers to manage hospital beds.

  8. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... And the bypass vessel is the so-called “internal mammary artery.” That’s an artery, as opposed to ... you very much. -- while I’m preparing the internal mammary artery for bypass. Good. All right. We ...

  9. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... as doctors use for this operation is “TECAB,” meaning “Totally Endoscopic Coronary Artery Bypass.” This procedure will ... make sure his vessels are able for bypass, meaning doing the CT angiograph for the peripheral arteries. ...

  10. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... is pulsating behind the fascia. Here is some muscle. Here we have the apex or tip of ... tissue. It then turns into the transverse thoracic muscle here. This bypass vessel has an extremely long ...

  11. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... sure that we preserve this bypass vessel very well in order to achieve this. So I go ... French quick-draw Venus cardiac visions cannula as well, which will draw back, go to the heart- ...

  12. PILOT STUDY RESULTS OF THE INFLUENCE OF CITICOLINE AND PIRIBEDIL ON COGNITIVE FUNCTION IN PATIENTS WITH ISCHEMIC HEART DISEASE AFTER CORONARY ARTERY BYPASS SURGERY

    Directory of Open Access Journals (Sweden)

    M. M. Petrova

    2015-09-01

    Full Text Available Aim. To reveal cognitive deficit after coronary artery bypass, the influence of citicoline, piribedil on the state of higher cerebral functions in the early and late periods after surgery.Material and methods. The study included 94 patients with ischemic heart disease. All patients were divided into 3 groups. Patients of the first group (n=30 were prescribed citicoline as a cerebral neuroprotective drug. Patients of the second group (n=32 had piribedil in addition to standard therapy. Patients of the control group (n=32 had only a standard treatment without any neuroprotective drugs. All patients underwent coronary artery bypass surgery. The cognitive function was assessed before, 10 days after and six months after coronary artery bypass.Results. Patients of group 1 and 2 had achieved pre-surgical levels of cognitive tests results 6 months after coronary artery bypass. The control group had achieved initial levels only in three tests: visual memory (immediate simulation; p=0.008, categorical association (p=0.002, clock drawing test (Wilcoxon test; p=0,005, while other indices were reduced in comparison with the initial ones.Conclusion. The obtained results allow considering the studied drugs as a protectors of cognitive function after surgery. Randomized controlled double-blind studies on large samples are needed to confirm these results.

  13. Influence of an external medium on the ionic distribution in human allantochorial placental vessels

    International Nuclear Information System (INIS)

    Micro-Particle Induced X-ray Emission (PIXE) analysis was applied to determine the ionic composition of different layers of human placental vessels. The laminae of arterial walls were clearly identified by means of their elemental maps. In the same manner, the endothelial cells bordering the lumen were identified, cell by cell, and analyzed separately. Using this model, we investigated the influence of incubations in various physiological fluids on the ionic composition of the walls and of endothelial cells

  14. Influence of crack depth on the fracture toughness of reactor pressure vessel steel

    International Nuclear Information System (INIS)

    The Heavy Section Steel Technology Program (HSST) at Oak Ridge National Laboratory (ORNL) is investigating the influence of flaw depth on the fracture toughness of reactor pressure vessel (RPV) steel. Recently, it has been shown that, in notched beam testing, shallow cracks tend to exhibit an elevated toughness as a result of a loss of constraint at the crack tip. The loss of constraint takes place when interaction occurs between the elastic-plastic crack-tip stress field and the specimen surface nearest the crack tip. An increased shallow-crack fracture toughness is of interest to the nuclear industry because probabilistic fracture-mechanics evaluations show that shallow flaws play a dominant role in the probability of vessel failure during postulated pressurized-thermal-shock (PTS) events. Tests have been performed on beam specimens loaded in 3-point bending using unirradiated reactor pressure vessel material (A533 B). Testing has been conducted using specimens with a constant beam depth (W = 94 mm) and within the lower transition region of the toughness curve for A533 B. Test results indicate a significantly higher fracture toughness associated with the shallow flaw specimens compared to the fracture toughness determined using deep-crack (a/W = 0.5) specimens. Test data also show little influence of thickness on the fracture toughness for the current test temperature (-60 degree C). 21 refs., 5 figs., 3 tabs

  15. Stress-intensity-factor influence coefficients for axial and circumferential flaws in reactor pressure vessels

    International Nuclear Information System (INIS)

    Weight-function techniques in linear elastic fracture mechanics utilize stress-intensity-factor influence coefficients K* and superposition principles to compute stress intensity factors. This paper presents influence coefficients for two flaw geometries often employed in fracture analyses of reactor pressure vessels: (1) infinitely long, axial, inside-surface flaws and (2) 360 degrees, circumferential, inside-surface flaws. Calculations were performed using ABAQUS, a nuclear quality assurance (NQA-1) certified finite-element program which employs a highly accurate crack extension technique for the computation of theJ-integral. Influence coefficients are computed for flaw depths in the range 0.01 ≤ a/T ≤ 0.9 with particular emphasis on shallow flaws (a/T ≤ 0. 1). This study addresses vessels having R/T = 10 which is appropriate for most PWRs in USA. The influence coefficients have been implemented in the FAVOR fracture-mechanics code currently being developed under the NRC-funded HSST Program at ORNL

  16. Cardiopulmonary bypass in pregnancy.

    Science.gov (United States)

    Pomini, F; Mercogliano, D; Cavalletti, C; Caruso, A; Pomini, P

    1996-01-01

    The cardiopathic patient can sustain acute heart failure during pregnancy. In such cases, if open heart operation is necessary to save the patient's life, the fetus could be seriously compromised after exposure to cardiopulmonary bypass. From 1958 to 1992, 69 reports of cardiac operations during pregnancy with the aid of cardiopulmonary bypass have been published. Maternal mortality was 2.9%. Embryofetal mortality was 20.2%. Examining only the last 40 patients, maternal and embryofetal mortality were 0.0% and 12.5%, respectively. Embryofetal mortality was 24.0% when hypothermia was used, compared with 0.0% while operating in normothermia. Maternal mortality did not change. The use of hypothermia during cardiopulmonary bypass provoked uterine contractions in several patients. Hypothermia decreases O2 exchange through the placenta. Pump flow and mean arterial pressure during cardiopulmonary bypass seem to be the most important parameters that influence fetal oxygenation. We speculate that cardiac operation is not a contraindication to pregnancy prolongation. PMID:8561577

  17. Cerebral autoregulation and flow/metabolism coupling during cardiopulmonary bypass: the influence of PaCO2

    International Nuclear Information System (INIS)

    Measurement of 133Xe clearance and effluent cerebral venous blood sampling were used in 38 patients to determine the effects of cardiopulmonary bypass, and of maintaining temperature corrected or noncorrected PaCO2 at 40 mm Hg on regulation of cerebral blood flow (CBF) and flow/metabolism coupling. After induction of anesthesia with diazepam and fentanyl, mean CBF was 25 ml X 100 g-1 X min-1 and cerebral oxygen consumption, 1.67 ml X 100 g-1 X min-1. Cerebral oxygen consumption during nonpulsatile cardiopulmonary bypass at 26 degrees C was reduced to 0.42 ml X 100 g-1 X min-1 in both groups. CBF was reduced to 14-15 ml X 100 g-1 X min-1 in the non-temperature-corrected group (n = 21), was independent of cerebral perfusion pressure over the range of 20-100 mm Hg, but correlated with cerebral oxygen consumption. In the temperature-corrected group (n = 17), CBF varied from 22 to 32 ml X 100 g-1 X min-1, and flow/metabolism coupling was not maintained (i.e., CBF and cerebral oxygen consumption varied independently). However, variation in CBF correlated significantly with cerebral perfusion pressure over the pressure range of 15-95 mm Hg. This study demonstrates a profound reduction in cerebral oxygen consumption during hypothermic nonpulsatile cardiopulmonary bypass. When a non-temperature-corrected PaCO2 of approximately 40 mm Hg was maintained, CBF was lower, and analysis of pooled data suggested that CBF regulation was better preserved, i.e., CBF was independent of pressure changes and dependent upon cerebral oxygen consumption

  18. Cerebral autoregulation and flow/metabolism coupling during cardiopulmonary bypass: the influence of PaCO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Murkin, J.M.; Farrar, J.K.; Tweed, W.A.; McKenzie, F.N.; Guiraudon, G.

    1987-09-01

    Measurement of /sup 133/Xe clearance and effluent cerebral venous blood sampling were used in 38 patients to determine the effects of cardiopulmonary bypass, and of maintaining temperature corrected or noncorrected PaCO/sub 2/ at 40 mm Hg on regulation of cerebral blood flow (CBF) and flow/metabolism coupling. After induction of anesthesia with diazepam and fentanyl, mean CBF was 25 ml X 100 g-1 X min-1 and cerebral oxygen consumption, 1.67 ml X 100 g-1 X min-1. Cerebral oxygen consumption during nonpulsatile cardiopulmonary bypass at 26 degrees C was reduced to 0.42 ml X 100 g-1 X min-1 in both groups. CBF was reduced to 14-15 ml X 100 g-1 X min-1 in the non-temperature-corrected group (n = 21), was independent of cerebral perfusion pressure over the range of 20-100 mm Hg, but correlated with cerebral oxygen consumption. In the temperature-corrected group (n = 17), CBF varied from 22 to 32 ml X 100 g-1 X min-1, and flow/metabolism coupling was not maintained (i.e., CBF and cerebral oxygen consumption varied independently). However, variation in CBF correlated significantly with cerebral perfusion pressure over the pressure range of 15-95 mm Hg. This study demonstrates a profound reduction in cerebral oxygen consumption during hypothermic nonpulsatile cardiopulmonary bypass. When a non-temperature-corrected PaCO/sub 2/ of approximately 40 mm Hg was maintained, CBF was lower, and analysis of pooled data suggested that CBF regulation was better preserved, i.e., CBF was independent of pressure changes and dependent upon cerebral oxygen consumption.

  19. Obesity influences propranolol pharmacokinetics in patients undergoing coronary artery bypass grafting employing cardiopulmonary bypass Influência da obesidade na farmacocinética do propranolol em pacientes submetidos à revascularização do miocárdio com circulação extracorpórea

    OpenAIRE

    Valéria Adriana Pereira; Maria José Carvalho Carmona; Célia Etsuco Kobayashi Omosako; José Otávio Costa Auler Júnior; Silvia Regina Cavani Jorge Santos

    2003-01-01

    Propranolol plasma levels and kinetic disposition may be altered by hypothermic cardiopulmonary bypass (CPB-H). We investigated the potential influence of obesity on propranolol pharmacokinetics in patients undergoing coronary artery bypass grafting employing CPB-H. Fifteen patients, receiving propranolol perorally pre- (10-40 mg, 2-3 times a day) and post-operatively (10 mg, once a day) were distributed in two groups, based on body mass index (BMI), in obese (n = 9, BMI: mean 29.4 kg/m²) and...

  20. Extra-intracranial standard bypass in the elderly

    DEFF Research Database (Denmark)

    Sandow, Nora; von Weitzel-Mudersbach, Paul; Rosenbaum, Sverre;

    2013-01-01

    Patients with chronic atherosclerotic vessel occlusion and cerebrovascular hemodynamic insufficiency may benefit from extra-intracranial (EC-IC) bypass surgery. Due to demographic changes, an increasing number of elderly patients presents with cerebrovascular hemodynamic insufficiency. So far......, little data for EC-IC bypass surgery in elderly patients suffering occlusive cerebrovascular disease are available. We therefore designed a retrospective study to address the question whether EC-IC bypass is a safe and efficient treatment in a patient cohort ≥70 years....

  1. Influences of physical properties of two-phase mixture on void fraction in an annular vessel

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-Ming; BI Qin-Cheng; FENG Quan-Ke; CHEN Ting-Kuan; DU She-Jiao

    2004-01-01

    To keep the void fraction of two-phase hydrogen in the moderator cell of the cold neutron source (CNS)of China Advanced Research Reactor (CARR) to a specified range, an annular vessel with the same size as the actual moderator cell was used as test section. Deionized water and alcohol, sucrose, and sodium chloride solutions with different concentrations were used as working fluid to find out influences of physical properties, such as density, viscosity and surface tension, of the two-phase mixture on void fraction. The tests proved that the ratio of surface tension to density of liquid phase has great influence on void fraction: the larger the ratio, the smaller the void fraction.Since the ratio of surface tension to density of Freon 113 is lower than that of liquid hydrogen, Freon 113 can be used as a working fluid to study the void fraction in the two-phase hydrogen thermosiphon loop in the CNS of CARR and the results will be conservative.

  2. Coronary artery bypass surgery without cardiopulmonary bypass: short- and mid-term results.

    Science.gov (United States)

    Mishra, Y; Mehta, Y; Kohli, V M; Kohli, V; Mairal, M; Mishra, A; Bapna, R K; Trehan, N

    1997-01-01

    From March 1994 to April 1997, 433 patients had undergone coronary artery bypass grafting without cardiopulmonary bypass in our institute. Sixty-eight patients had various organ dysfunctions and/or aortic atheroma or calcification and were regarded as high risk for cardiopulmonary bypass. In 277 patients surgery was performed through midline sternotomy, while in 156 minithoracotomy approach was used. In 361 patients single coronary artery bypass grafting was done, and in 72 two-coronary arteries were bypassed. In 63 patients who had graftable vessels in anterior wall and diffusely diseased ungraftable vessels in posterolateral and/or inferior wall, transmyocardial laser revascularisation was also done along with coronary artery bypass grafting to achieve complete myocardial revascularisation. Nine patients in this series were also subjected to simultaneous carotid endarterectomy along with myocardial revascularisation. In two patients complementary percutaneous transluminal coronary angioplasty of left circumflex coronary artery was done five days after minithoracotomy and left internal mammary artery to left anterior descending coronary artery bypass grafting. Forty-two cases were extubated in operating room. Average blood loss was 260 ml. Six patients were reexplored for postoperative bleeding. Seven patients had perioperative myocardial infarction. One developed neurological complication. Hospital mortality was 2.3 percent (10/433 cases) and four deaths were due to malignant ventricular arrhythmias. Nine patients developed chest wound complications. Average hospital stay after operation was six days, 423 patients were discharged from hospital and all of them were asymptomatic. During three years follow-up (range 3 to 38 months) there were three known cardiac deaths. Ninety percent (391) patients reported to the follow-up clinic and 91 percent of them were angina-free. In patients who were subjected to transmyocardial laser revascularisation along with coronary

  3. WWER-1000 core loading characteristic influence on irradiation conditions of surveillance specimens and reactor pressure vessel

    International Nuclear Information System (INIS)

    Irradiation conditions of WWER-1000 surveillance specimens and reactor pressure vessel are comparative analyzed for various core loadings. It is proved that the fluences onto specimens don't correlate with ones onto pressure vessel. It is shown that the reconstruction technique using to surveillance specimens of the standard program implemented at the most of the power units with WWER-1000 allows obtaining reliable information on the reactor pressure vessel metal states

  4. Coronary Artery Bypass

    Science.gov (United States)

    ... to 3 days in the Intensive Care Unit (ICU). Life After Bypass After bypass surgery, your doctor will recommend that you join a cardiac rehabilitation program. These programs help you make lifestyle changes ...

  5. Influence of residual stresses on failure pressure of cylindrical pressure vessels

    Institute of Scientific and Technical Information of China (English)

    M. Jeyakumar; T. Christopher

    2013-01-01

    The utilization of pressure vessels in aerospace applications is manifold. In this work, finite element analysis (FEA) has been carried out using ANSYS software package with 2D axisym-metric model to access the failure pressure of cylindrical pressure vessel made of ASTM A36 carbon steel having weld-induced residual stresses. To find out the effect of residual stresses on failure pressure, first an elasto-plastic analysis is performed to find out the failure pressure of pressure vessel not having residual stresses. Then a thermo-mechanical finite element analysis is performed to assess the residual stresses developed in the pressure vessel during welding. Finally one more elasto-plastic analysis is performed to assess the effect of residual stresses on failure pressure of the pressure vessel having residual stresses. This analysis indicates reduction in the failure pressure due to unfavorable residual stresses.

  6. Burnup influence on the VVER-1000 reactor vessel neutron fluence evaluation

    International Nuclear Information System (INIS)

    The neutron fluence of the vessels of the reactors is determined regularly accordingly the RPV Surveillance Program of the Kozloduy NPP Unit 5 and 6 in order to assess the state of the metal vessel and their radiation damaging. The calculations are carried out by the method of discrete ordinates used in the TORT program for operated reactor cycles. An average reactor spectrum corresponding to fresh U-235 fuel is used as an input neutron source. The impact of the burn up of the fuel on the neutron fluence of VVER-1000 reactor vessel is evaluated. The calculations of isotopic concentrations of U-235 and Pu-239 corresponding to 4 years burn up were performed by the module SAS2H of the code system SCALE 4.4. Since fresh fuel or 4 years burn up fuel assembly are placed in periphery of reactor core the contribution of Pu-239 of first year burn up and of 4 years burn up is taken in consideration. Calculations of neutron fluence were performed with neutron spectrum for fresh fuel, for 1 year and for 4 years burn up fuel. Correction factors for neutron fluence at the inner surface of the reactor vessel, in 1/4 depth of the vessel and in the air behind the vessel were obtained. The correction coefficient could be used when the neutron fluence is assessed so in verification when the measured activity of ex-vessel detectors is compared with calculated ones. (authors)

  7. Geometric influences upon stress intensity distributions along reactor vessel nozzle cracks

    International Nuclear Information System (INIS)

    This paper describes the results obtained by applying a computer assisted photoelastic technique for estimating Mode I stress intensity factor (SIF) distributions for mathematically intractable three-dimensional problems to the reactor vessel nozzle corner crack problem. Two significantly different test programs were employed and results were compared with the literature. Frozen stress photoelastic experiments were conducted on two classes of nozzle corner cracks: (i) Researchers at the Delft University Laboratory for Nuclear Engineering have developed a nozzle-flat plate geometry which is loaded in remote uniaxial tension normal to the flaw. The transverse tension can then be included analytically. Their results indicate that such a model accurately predicts fatigue crack growth for the corresponding cracked nozzle in a pressure vessel for thin walled vessels. The test geometry identified as No.4 in the Delft work was studied experimentally in the present work. (ii) Researchers at Oak Ridge National Laboratory developed a technique for predicting SIF's in cracked nozzles in thick walled pressure vessels from residual static strength tests on fatigue cracked plastic models of nozzle-cylinder intersections. The test geometry identified as the 'small thick walled vessel' in the Oak Ridge program was studied experimentally in the present work

  8. Geometric influences upon stress intensity distributions along reactor vessel nozzle cracks

    International Nuclear Information System (INIS)

    This paper describes the results obtained by applying a computer assisted photoelastic technique developed by the senior author and his associates for estimating Mode 1 stress intensity factor (SIF) distributions for mathematically intractable three-dimensional problems to the reactor vessel nozzle corner crack problem. Two significantly different test programs were employed and results were compared with the literature. Frozen stress photoelastic experiments were conducted on two classes of nozzle corner cracks: (1) Researchers at the Delft University Laboratory for Nuclear Engineering have developed a nozzle-flat plate geometry which is loaded in remote uniaxial tension normal to the flaw. The transverse tension can then be included analytically. Their results indicate that such a model accurately predicts fatigue crack growth for the corresponding cracked nozzle in a pressure vessel for thin walled vessels. The test geometry identified as No. 4 in the Delft work was studied experimentally in the present work. (ii) Researchers at Oak Ridge National Laboratory developed a technique for predicting SIFs in cracked nozzles in thick walled pressure vessels from residual static strength tests on fatigue cracked plastic models of nozzle-cylinder interactions. The test geometry identified as the 'small thick walled vessel' in the Oak Ridge program was studied experimentally in the present work. (Auth.)

  9. Clogging the enrichment bypass

    International Nuclear Information System (INIS)

    The issue that has come to be known as the bypass is the latest dispute in the continuing saga of uranium trade between the United States and the Commonwealth of Indepenent States. Bypass deals now being conducted by US utilities have drawn heavy criticism from the US Department of Commerce but are perfectly legal under the terms of the Suspension Agreements. Urged on by the United States Enrichment Corporation, the US DOC intends to stop, or at least severely restrict, bypass deals. Using a recent agreement with Kazakhstan as a case study, this article reviews the implications of such bypass deals

  10. Oxidative Stress in Hypobaric Hypoxia and Influence on Vessel-Tone Modifying Mediators

    OpenAIRE

    Pichler Hefti, Jacqueline Renée; Sonntag, Denise; Hefti, Urs; Risch, Lorenz; Schoch, Otto D; Turk, Alexander J; Hess, Thomas; Bloch, Konrad E; Maggiorini,Marco; Merz, Tobias Michael; Weinberger, Klaus M.; Huber, Andreas R

    2013-01-01

    Increased pulmonary artery pressure is a well-known phenomenon of hypoxia and is seen in patients with chronic pulmonary diseases, and also in mountaineers on high altitude expedition. Different mediators are known to regulate pulmonary artery vessel tone. However, exact mechanisms are not fully understood and a multimodal process consisting of a whole panel of mediators is supposed to cause pulmonary artery vasoconstriction. We hypothesized that increased hypoxemia is associated with an ...

  11. Oxidative stress in hypobaric hypoxia and influence on vessel-tone modifying mediators

    OpenAIRE

    Pichler Hefti, Jacqueline; Sonntag, Denise; Hefti, Urs; Risch, Lorenz; Schoch, Otto D; Turk, Alexander J; Hess, Thomas; Bloch, Konrad E; Maggiorini,Marco; Merz, Tobias M; Weinberger, Klaus M.; Huber, Andreas R

    2013-01-01

    Increased pulmonary artery pressure is a well-known phenomenon of hypoxia and is seen in patients with chronic pulmonary diseases, and also in mountaineers on high altitude expedition. Different mediators are known to regulate pulmonary artery vessel tone. However, exact mechanisms are not fully understood and a multimodal process consisting of a whole panel of mediators is supposed to cause pulmonary artery vasoconstriction. We hypothesized that increased hypoxemia is associated with an incr...

  12. Coronary artery bypass grafting in an achondroplastic dwarf.

    OpenAIRE

    Balaguer, J M; Perry, D; Crowley, J; Moran, J. M.

    1995-01-01

    To our knowledge, coronary bypass for complications of coronary artery disease in achondroplasia has not previously been described. Achondroplasia, in and of itself, is not a contraindication to coronary bypass. Although the anatomic reserve of saphenous vein is less in achondroplastic dwarfs than in people of normal stature, that vessel and the internal mammary artery can be harvested in routine fashion. A 60-year-old woman with several risk factors for coronary artery disease underwent succ...

  13. Pressure distension in leg vessels as influenced by prolonged bed rest and a pressure habituation regimen.

    Science.gov (United States)

    Eiken, Ola; Mekjavic, Igor B; Kounalakis, Stylianos N; Kölegård, Roger

    2016-06-15

    Bed rest increases pressure distension in arteries, arterioles, and veins of the leg. We hypothesized that bed-rest-induced deconditioning of leg vessels is governed by the removal of the local increments in transmural pressure induced by assuming erect posture and, therefore, can be counteracted by intermittently increasing local transmural pressure during the bed rest. Ten men underwent 5 wk of horizontal bed rest. A subatmospheric pressure (-90 mmHg) was intermittently applied to one lower leg [pressure habituation (PH) leg]. Vascular pressure distension was investigated before and after the bed rest, both in the PH and control (CN) leg by increasing local distending pressure, stepwise up to +200 mmHg. Vessel diameter and blood flow were measured in the posterior tibial artery and vessel diameter in the posterior tibial vein. In the CN leg, bed rest led to 5-fold and 2.7-fold increments (P tibial artery pressure-distension and flow responses, respectively, and to a 2-fold increase in tibial vein pressure distension. In the PH leg, arterial pressure-distension and flow responses were unaffected by bed rest, whereas bed rest led to a 1.5-fold increase in venous pressure distension. It thus appears that bed-rest-induced deconditioning of leg arteries, arterioles, and veins is caused by removal of gravity-dependent local pressure loads and may be abolished or alleviated by a local pressure-habituation regimen. PMID:27079693

  14. Flow characteristics in narrowed coronary bypass graft

    Science.gov (United States)

    Bernad, S. I.; Bosioc, A.; Bernad, E. S.; Petre, I.; Totorean, A. F.

    2016-06-01

    Tortuous saphenous vein graft (SVG) hemodynamics was investigated using computational fluid dynamics (CFD) techniques. Computed tomography (CT) technology is used for non-invasive bypass graft assessment 7 days after surgery. CT investigation shown two regions with severe shape remodelling first is an elbow type contortion and second is a severe curvature with tortuous area reduction. In conclusion, the helical flow induced by vessel torsion may stabilize the blood flow in the distal part of the SVG, reducing the flow disturbance and suppressing the flow separation, but in the distal end of the graft, promote the inflammatory processes in the vessels.

  15. Coronary bypass using bilateral internal mammary arteries in an achondroplast.

    Science.gov (United States)

    Alassal, Mohamed Abdulwahab; Youssef, Mostafa; Koudieh, Mohammed

    2015-01-01

    Coronary bypass grafting for ischemic heart disease in achondroplastic dwarfs is very rare. Shortage of veins and inadequate vein quality may cause difficulties during surgery. Only 2 cases of coronary bypass surgery in an achondroplastic dwarf, in which the left internal mammary artery and vein grafts were used, have been reported. We describe the case of a 55-year-old male achondroplastic dwarf who had triple-vessel coronary disease and underwent successful coronary bypass surgery using one saphenous vein graft and bilateral internal mammary artery grafts. The anatomic and surgical challenges in achondroplasia are highlighted. PMID:24887865

  16. The influence on PGI2-like activity of blood vessel wall following γ ray irradiation

    International Nuclear Information System (INIS)

    In the previous work, it has been shown that the reaction of blood platelet aggregation is risen during the early days following γ ray irradiation of large doses. In this paper, the changes of Rat PGI2-like activity with inhibiting platelet aggregation after γ ray irradiation of 8 Gy are reported. The results indicated that the activity was reduced at the first day after radiation, then recovered at the third day, lowered again at the 5-7 days. The changes have significant concern between the increase of blood platelet aggregation of Rats and the inhibition of PGI2-like activity of blood vessel wall following γ ray irradiation

  17. Influence of The Iron Multigroup Neutron Cross Section Libraries on the WWER Vessel Neutron Flux Evaluation

    International Nuclear Information System (INIS)

    Comparative calculations of the experimental benchmark of iron sphere with Cf source have been performed in order to assess the sensibility of the calculations of neutron transmission through iron media to different multigroup libraries generated on the base of ENDF/B-6 and ENDF/B-4. Similar calculations and comparison of the neutron flux passed through media typical as geometry and material compositions for the WWER-1000 and WWER-440 vessels have been carried out. Except the already well-known problem dependent libraries, the new libraries BGL-440 and BGL-1000 generated on the base of ENDF/B-6 for the WWER-440 and WWER-1000 RPV neutron fluence calculations have been applied. The solving of neutron transport through iron media using ENDF/B-6 data gives better consistency with the experiment than using ENDF/B-4. The latter underestimate the experimental fluxes more substantially in the energy range above 2 MeV and the evaluations of the neutron flux responses for the WWER vessel surveillance is preferably to be carried out by the appropriate BGL library. Key words: neutron transport, multigroup neutron cross section libraries

  18. Influence of dexamithasone-coated nitinol stent on neointimal formation in the canine great vessel model

    International Nuclear Information System (INIS)

    To evaluate the effect of dexamethasone(DM) and polyurethane(PU)-coated nitinol stent on neoinitimal formation in the canine great vessels. Thirty-six nitinol wire stents were implanted in the abdominal aorta and inferior vena cava(IVC) of six dogs. In each animal, six different types of stent (NC, non-coated ; PU, polyurethane coated ; DM, DM and polyurethane coated) were serially positioned in permutationally possible order in the aorta be low the renal arteries and in the IVC below the renal veins. For DM stent an in-vitro drug release test was performed to determine the stability of DM release. The thickness of the intima and media of the aorta and of the intima of the IVS were measured three (n=3) or six months (n=3) after stent placement at and between the wires. In the in-vitro study, 25% of DM was released during the first week, and the subsequent release rate was 3 μg/day for 6 months. The intima-to-media ratio of DM-stented aorta was less than in aortas where PU or NC stents were used (p0.05). In this canine great vessel model, newly designed DM-coated stent decreased neointimal formation

  19. The influence of nutrients, biliary-pancreatic secretions, and systemic trophic hormones on intestinal adaptation in a Roux-en-Y bypass model

    DEFF Research Database (Denmark)

    Taqi, Esmaeel; Wallace, Laurie E; de Heuvel, Elaine;

    2010-01-01

    The signals that govern the upregulation of nutrient absorption (adaptation) after intestinal resection are not well understood. A Gastric Roux-en-Y bypass (GRYB) model was used to isolate the relative contributions of direct mucosal stimulation by nutrients, biliary-pancreatic secretions, and sy...

  20. Bypassing damaged nervous tissue

    CERN Document Server

    Shneider, M N

    2016-01-01

    We show the principal ability of bypassing damaged demyelinated portions of nervous tissue, thereby restoring its normal function for the passage of action potentials. We carry out a theoretical analysis on the basis of the synchronization mechanism of action potential propagation along a bundle of neurons, proposed recently in [1]. And we discuss the feasibility of implement a bypass to restore damaged nervous tissue and creating an artificial neuron network.

  1. Extracranial–intracranial bypass for Takayasu’s arteritis: A case report

    Directory of Open Access Journals (Sweden)

    Richard M. Young, M.D.

    2014-12-01

    Conclusion: STA–MCA bypass to enhance cerebral blood flow in the setting of stroke symptoms due to Takayasu’s arteritis can serve as a bridge before definitive cardiothoracic treatment of the great vessels.

  2. Influence of reactor vessel nodalization in the coupled code analysis of Asymmetric Main Feedwater Isolation

    International Nuclear Information System (INIS)

    Asymmetric Main Feedwater Isolation (AMFWI) transient in one Steam Generator (SG) for NPP Krsko using RELAP5 standalone code and coupled code RELAP5- QUABOX/CUBBOX (R5QC) was analyzed. In the RELAP5 standalone calculation, a point kinetics model was used, while in the coupled code a three-dimensional (3D) neutronics model of QUABOX with different RELAP5 nodalization schemes of reactor vessel was used. Both code versions use best-estimate thermal-hydraulic system code for all components in the plant and include realistic description of plant protection and control systems. Two different types of calculations were performed: with and without automatic control rod system available. The AMFWI transient causes the great asymmetry of the transferred heat in the SGs and subsequently the asymmetry of the power produced across the core due to different reactivity feedback resulting from the thermal-hydraulic channels assigned to different loops. The work presented in the paper is a part of validation of the 3D coupled code R5QC in the analysis of asymmetric transients.(author)

  3. Influence of fluence rate on radiation-induced mechanical property changes in reactor pressure vessel steels

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, J.R.; Hiser, A.L. (Materials Engineering Associates, Inc., Lanham, MD (USA))

    1990-03-01

    This report describes a set of experiments undertaken using a 2 MW test reactor, the UBR, to qualify the significance of fluence rate to the extent of embrittlement produced in reactor pressure vessel steels at their service temperature. The test materials included two reference plates (A 302-B, A 533-B steel) and two submerged arc weld deposits (Linde 80, Linde 0091 welding fluxes). Charpy-V (C{sub v}), tension and 0.5T-CT compact specimens were employed for notch ductility, strength and fracture toughness (J-R curve) determinations, respectively. Target fluence rates were 8 {times} 10{sup 10}, 6 {times} 10{sup 11} and 9 {times} 10{sup 12} n/cm{sup 2} {minus}s{sup {minus}1}. Specimen fluences ranged from 0.5 to 3.8 {times} 10{sup 19} n/cm{sup 2}, E > 1 MeV. The data describe a fluence-rate effect which may extend to power reactor surveillance as well as test reactor facilities now in use. The dependence of embrittlement sensitivity on fluence rate appears to differ for plate and weld deposit materials. Relatively good agreement in fluence-rate effects definition was observed among the three test methods. 52 figs., 4 tabs.

  4. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  5. Night eating status and influence on body weight, body image, hunger, and cortisol pre- and post- Roux-en-Y Gastric Bypass (RYGB) surgery

    OpenAIRE

    Morrow, J; Gl{\\"}uck, M.; Lorence, M.; Flancbaum, L.; Geliebter, A.

    2008-01-01

    Night Eating Syndrome is a common disorder in severely obese individuals and may be associated with hypothalamic pituitary adrenal (HPA) axis dysregulation. This study compared night eaters (NE) and comparably obese controls (C) pre- and post-Roux-en-Y Gastric Bypass surgery at 2 and 5 months, following an overnight fast on hormonal measures associated with HPA axis and related appetite and psychological measures. There were 24 (10 NE, 14 C) clinically severely obese participants (body mass i...

  6. Contrast-enhanced cardiac MRI before coronary artery bypass surgery: impact of myocardial scar extent on bypass flow

    International Nuclear Information System (INIS)

    The aim of the study was to relate the extent of myocardial late gadolinium enhancement (LGE) in cardiac MRI to intraoperative graft flow in patients undergoing coronary artery bypass graft (CABG) surgery. Thirty-three CAD patients underwent LGE MRI before surgery using an inversion-recovery GRE sequence (turboFLASH). Intraoperative graft flow in Doppler ultrasonography was compared with the scar extent in each coronary vessel territory. One hundred and fourteen grafts were established supplying 86 of the 99 vessel territories. A significant negative correlation was found between scar extent and graft flow (r = -0.4, p -1; p < 0.0001). In summary, the extent of myocardial scar as defined by contrast-enhanced MRI predicts coronary bypass graft flow. Beyond the probability of functional recovery, preoperative MRI might add value to surgery planning by predicting midterm bypass graft patency. (orig.)

  7. Influence of gamma irradiation on the deterioration of reactor pressure vessel materials and on reactor dosimetry measurements. Final report

    International Nuclear Information System (INIS)

    Radiation embrittlement of pressure vessel steel in mixed neutron-gamma fields is mostly determined by neutrons, but in some cases also by gamma-radiation. Depending on the reactor type, gamma radiation can influence evaluations of lead factors of surveillance specimens, effect the interpretation of results of irradiation experiments and finally, it can result in changed pressure vessel lifetime evaluations. The project aimed at the evaluation of the importance of gamma radiation for RPV steel damage for several types of light-water reactors. Absolute neutron and gamma fluence rate spectra had been calculated for the Russian PWR types VVER-440 and two core loading variants of VVER-1000, for a German 1300 MW PWR and a German 900 MW BWR. Based on the calculated spectra several flux integrals and radiation damage parameters were derived for the region of the azimuthal flux maxima in the mid-planes for different radial positions between core and biological shield, especially, at the inner and outer surfaces of the PV walls, at the (1/4)-PV-thickness and at the surveillance positions. Fissionable materials are often used as activation detectors for neutron fluence measurements. To get the real value the analysis demands to take into account the gamma induced fissions. Therefore, the part of these fissions in the total number of fissions was estimated for the detector reactions 237Np(n,f) and 238U(n,f) in the calculated neutron/gamma fields. It has been found that considerable corrections of the neutron fluence measurements can be necessary, especially in case of 238U(n,f). Most of the calculations were performed using a three-dimensional synthesis of 2D/1D-flux distributions obtained by the SN-code DORT with the BUGLE-96T group cross-section library. (orig.)

  8. Bypass Flow Study

    International Nuclear Information System (INIS)

    The purpose of the fluid dynamics experiments in the MIR (Matched Index of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for the flow ratios between coolant channels and bypass gaps in the interstitial regions of typical prismatic standard fuel element (SFE) or upper reflector block geometries of typical Modular High-temperature Gas-cooled Reactors (MHTGR) in the limiting case of negligible buoyancy and constant fluid properties. The experiments use Particle Image Velocimetry (PIV) to measure the velocity fields that will populate the bypass flow study database.

  9. Bypass Flow Study

    Energy Technology Data Exchange (ETDEWEB)

    Richard Schultz

    2011-09-01

    The purpose of the fluid dynamics experiments in the MIR (Matched Index of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for the flow ratios between coolant channels and bypass gaps in the interstitial regions of typical prismatic standard fuel element (SFE) or upper reflector block geometries of typical Modular High-temperature Gas-cooled Reactors (MHTGR) in the limiting case of negligible buoyancy and constant fluid properties. The experiments use Particle Image Velocimetry (PIV) to measure the velocity fields that will populate the bypass flow study database.

  10. The Best Bypass Surgery Trial

    DEFF Research Database (Denmark)

    Møller, Christian H; Jensen, Birte Østergaard; Gluud, Christian; Perko, Mario J; Lund, Jens T; Andersen, Lars Willy; Madsen, Jan Kyst; Hughes, Pia; Steinbrüchel, Daniel A

    2007-01-01

    Recent trials suggest that off-pump coronary artery bypass grafting (OPCAB) reduces the risk of mortality and morbidity compared with conventional coronary artery bypass grafting (CCAB) using cardiopulmonary bypass. Patients with a moderate- to high-risk of complications after CCAB may have addit...

  11. Aortic valve bypass

    DEFF Research Database (Denmark)

    Lund, Jens T; Jensen, Maiken Brit; Arendrup, Henrik; Ihlemann, Nikolaj

    2013-01-01

    In aortic valve bypass (AVB) a valve-containing conduit is connecting the apex of the left ventricle to the descending aorta. Candidates are patients with symptomatic aortic valve stenosis rejected for conventional aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI...

  12. Bypassing AMPK Phosphorylation

    OpenAIRE

    Viollet, Benoit; Foretz, Marc; Schlattner, Uwe

    2014-01-01

    AMP-activated protein kinase (AMPK) functions as a signaling hub to balance energy supply with demand. Phosphorylation of activation loop Thr172 has been considered as an essential step in AMPK activation. In this issue of Chemistry & Biology, Scott and colleagues show that the small molecule direct AMPK activator, A-769662, bypasses this phosphorylation event, and acts synergistically with AMP on naive AMPK.

  13. Influence of the residual stresses and strains generated by heat treatments on the hydrogen embrittlement of a nuclear reactor pressure vessel

    International Nuclear Information System (INIS)

    The wall of a nuclear reactor pressure vessel can undergo a reduction of its mechanical properties due to the presence of hydrogen, a process known as hydrogen embrittlement (HE). A numerical model of hydrogen diffusion assisted by stress and strain was used in this paper to evaluate the HE process in the wall of a real nuclear reactor pressure vessel, formed by a bi-material (stainless steel and low carbon steel). In this sense, a quantitative analysis was carried out of the influence of tempering heat treatments conditions applied to these two steels on hydrogen concentration accumulated in the nuclear reactor vessel during its operation time. To this end, the most relevant parameters of these heat treatments were considered: (1) tempering temperature and (2) tempering time. (author)

  14. Divertor bypass in the Alcator C-Mod tokamak

    Science.gov (United States)

    Pitcher, C. S.; LaBombard, B.; Danforth, R.; Pina, W.; Silveira, M.; Parkin, B.

    2001-01-01

    The Alcator C-Mod divertor bypass has for the first time allowed in situ variations to the mechanical baffle design in a tokamak. The design utilizes small coils which interact with the ambient magnetic field inside the vessel to provide the torque required to control small flaps of a Venetian blind geometry. Plasma physics experiments with the bypass have revealed the importance of the divertor baffling to maintain high divertor gas pressures. These experiments have also indicated that the divertor baffling has only a limited effect on the main chamber pressure in C-Mod.

  15. Axillobifemoral bypass grafting

    Directory of Open Access Journals (Sweden)

    Davidović Lazar B.

    2004-01-01

    Full Text Available INTRODUCTION Axillo-femoral bypass (AxF means connecting the axillar and femoral artery with the graft that is placed subcutaneously [1]. Usually, this graft is connected with contralateral femoral artery via one accessory subcutaneous graft, and this connection is known as axillobifemoral bypass (AxFF. This extra-anatomic procedure is an alternative method to the standard reconstruction of aortoiliac region when there are contraindications for general or local reasons. OBJECTIVE The objective of this paper is to show early and late results of AxFF bypass grafting as well as to show the indications for AxFF bypass. METHODS The sample consisted of 37 patients. The procedure was performed in 28 patients who suffered from aortoiliac occlusive disease and who were at high risk due to the comorbidity- in one patient with the rupture of juxtarenal aneurysm of abdominal aorta; in five patients with aortoenteric fistula, in two patients with iatrogenic lesion of abdominal aorta and in one female patient with anus preternaturalis definitivus who was treated for rectovaginal fistula. Donor's right axillary artery was used in 26 cases (70.3%, and donor's left axillary artery was used in 9 cases (29.7%. Dacron graft was used in 34 patients and Polytetrafluo-roethlylene graft was used in three patients. Simultaneously, profundo-plastic was done in four patients and femoro-popliteal bypass was performed in three patients. In five patients who suffered from aortoenteric fistula, simultaneous intervention of gastrointerstinal system has been done, x2 test was used for statistical evaluation and life table method was used for verification of late graft patency. RESULTS The rate of early postoperative mortality was 13.5%. The causes of death were: sepsis -1, MOFS - 3, and infarct myocardium -1. The mean follow up period was 40.1 months, ranging from six months to 17 years. During the follow up period, an early graft thrombosis was identified in two and late graft

  16. Influence of heat treatments on thermoelectric power of pressure vessel steels: effect of microstructural evolutions of strongly segregated areas

    International Nuclear Information System (INIS)

    Thermoelectric power measurement (TEP) is a very potential non destructive evaluation method considered to follow ageing under neutron irradiation of pressure vessel steel of nuclear reactor. Prior to these problems, the aim of this study is to establish correlations between TEP variations and microstructural evolutions of pressure vessel steels during heat treatments. Different steels, permitting to simulate heterogeneities of pressure vessel steels and to deconvoluate main metallurgical phenomenons effects were studied. This work allowed to emphasize effect on TEP of: austenitizing and cooling conditions and therefore of microstructure, metallurgical transformations during tempering (recovery, precipitation of alloying elements), and particularly molybdenum precipitation associated to secondary hardening, residual austenite amount or partial austenitizing. (author)

  17. Controllability and Operability Analysis of Heat Exchanger Networks Including Bypasses

    OpenAIRE

    Hernández, S; Balcazar-López, L.; Sánchez-Márquez, J. A.; González-García, G.

    2010-01-01

    In this paper, the influence of bypasses in heat exchanger networks on theoretical control properties and closed-loop behavior was investigated. According to theoretical control properties obtained using the singular value decomposition technique, the presence of bypasses increases flexibility of the heat exchanger network. This result was corroborated using closed-loop dynamic simulations using a proportional integral controller and a proportional integral controller with dynamic estimati...

  18. STARDUST experimental campaign and numerical simulations: influence of obstacles and temperature on dust resuspension in a vacuum vessel under LOVA

    Science.gov (United States)

    Bellecci, C.; Gaudio, P.; Lupelli, I.; Malizia, A.; Porfiri, M. T.; Quaranta, R.; Richetta, M.

    2011-05-01

    Activated dust mobilization during a Loss of Vacuum Accident (LOVA) is one of the safety concerns for the International Thermonuclear Experimental Reactor (ITER). Intense thermal loads in fusion devices occur during plasma disruptions, edge localized modes and vertical displacement events. They will result in macroscopic erosion of the plasma facing materials and consequent accumulation of activated dust into the ITER vacuum vessel (VV). These kinds of events can cause dust leakage outside the VV that represents a high radiological risk for the workers and the population. A small facility, Small Tank for Aerosol Removal and Dust (STARDUST), was set up at the ENEA Frascati laboratories to perform experiments concerning the dust mobilization in a volume with the initial conditions similar to those existing in ITER VV. The aim of this work was to reproduce a low pressurization rate (300 Pa s-1) LOVA event in a VV due to a small air leakage for two different positions of the leak, at the equatorial port level and at the divertor port level, in order to evaluate the influence of obstacles and walls temperature on dust resuspension during both maintenance (MC) and accident conditions (AC) (Twalls = 25 °C MC, 110 °C AC). The dusts used were tungsten (W), stainless steel 316 (SS316) and carbon (C), similar to those produced inside the vacuum chamber in a fusion reactor when the plasma facing materials vaporize due to the high energy deposition. The experimental campaign has been carried out by introducing inside STARDUST facility an obstacle to simulate the presence of objects, such as divertor. In the obstacle a slit was cut to simulate the limiter-divertor gap inside ITER VV. In this paper experimental campaign results are shown in order to investigate how the divertor and limiter-divertor gap influence dust mobilization into a VV. A two-dimensional (2D) modelling of STARDUST was made using the CFD commercial code FLUENT, in order to get a preliminary overview of the

  19. Influence of Modelling Options in RELAP5/SCDAPSIM and MAAP4 Computer Codes on Core Melt Progression and Reactor Pressure Vessel Integrity

    OpenAIRE

    Siniša Šadek; Srđan Špalj; Bruno Glaser

    2010-01-01

    RELAP5/SCDAPSIM and MAAP4 are two widely used severe accident computer codes for the integral analysis of the core and the reactor pressure vessel behaviour following the core degradation. The objective of the paper is the comparison of code results obtained by application of different modelling options and the evaluation of influence of thermal hydraulic behaviour of the plant on core damage progression. The analysed transient was postulated station blackout in NPP Krško with a leakage from ...

  20. Coronary Artery Bypass

    Directory of Open Access Journals (Sweden)

    Kadri Ceberut

    2011-01-01

    Full Text Available Ancient schwannoma is a rare variant of neural tumors though rarely seen in the thorax. The combination with coronary artery diseases is also rare. Here we describe a 66 year-old male who had undergone one-stage combined surgery for thoracic ancient schwannomas removal and coronary artery disease. The masses were, respectively, 13 cm in the middle mediastinum and 5 cm in diameter originating from the intercostal nerve. The tumors were successfully removed using sternotomy, and then a coronary artery bypass grafting was performed. Here we discuss this rare tumor in relation to the relevant literature.

  1. Tumor Blood Vessel Dynamics

    Science.gov (United States)

    Munn, Lance

    2009-11-01

    ``Normalization'' of tumor blood vessels has shown promise to improve the efficacy of chemotherapeutics. In theory, anti-angiogenic drugs targeting endothelial VEGF signaling can improve vessel network structure and function, enhancing the transport of subsequent cytotoxic drugs to cancer cells. In practice, the effects are unpredictable, with varying levels of success. The predominant effects of anti-VEGF therapies are decreased vessel leakiness (hydraulic conductivity), decreased vessel diameters and pruning of the immature vessel network. It is thought that each of these can influence perfusion of the vessel network, inducing flow in regions that were previously sluggish or stagnant. Unfortunately, when anti-VEGF therapies affect vessel structure and function, the changes are dynamic and overlapping in time, and it has been difficult to identify a consistent and predictable normalization ``window'' during which perfusion and subsequent drug delivery is optimal. This is largely due to the non-linearity in the system, and the inability to distinguish the effects of decreased vessel leakiness from those due to network structural changes in clinical trials or animal studies. We have developed a mathematical model to calculate blood flow in complex tumor networks imaged by two-photon microscopy. The model incorporates the necessary and sufficient components for addressing the problem of normalization of tumor vasculature: i) lattice-Boltzmann calculations of the full flow field within the vasculature and within the tissue, ii) diffusion and convection of soluble species such as oxygen or drugs within vessels and the tissue domain, iii) distinct and spatially-resolved vessel hydraulic conductivities and permeabilities for each species, iv) erythrocyte particles advecting in the flow and delivering oxygen with real oxygen release kinetics, v) shear stress-mediated vascular remodeling. This model, guided by multi-parameter intravital imaging of tumor vessel structure

  2. The influence of vessel movements on the energy expenditure of fishermen in relation to activities and occupational tasks on board

    DEFF Research Database (Denmark)

    Breidahl, Tomas; Christensen, Michael; Jepsen, Jørgen Riis;

    2015-01-01

    additional energy expenditure relative to the energy expenditure during sleep was recorded during activities such as navigation, fishing, and machine handling and was correlated to the vessels' recorded movements (pitch/roll). Data were analysed by linear regression. RESULTS: Roll and pitch were less than 10......BACKGROUND: Previous studies of professional fishing activities have indicated that vessel movements correlate to fishermen's energy expenditure. We have previously demonstrated that even in calm weather, the heel and pitch significantly increase the fishermen's energy expenditure, ignoring the...... recorded their work activities on an hourly basis during a 4 days fishing voyage. The energy expenditure was estimated with a body monitoring system (SenseWear Pro 3) carried as an armband, placed on the right upper arm. The vessels' movements were assessed by a gyroscope placed in the wheelhouse. The...

  3. Innovations in Pedriatic Cradiopulmonary Bypass: a continuous process of quality improvement

    OpenAIRE

    Golab, Hanna

    2011-01-01

    textabstractCardiopulmonary bypass (CPB) is defined as a technique that temporarily replaces the function of the heart and lungs, maintaining an adequate blood circulation and oxygen content of the body during surgery of the heart and great vessels. The current practice of cardiopulmonary bypass was achieved through the efforts of a numbers of individuals who believed that artificial cardiopulmonary support could replace the body’s own circulatory and respiratory systems. Collaborative effort...

  4. Influence of localized plasticity on Stress Corrosion Cracking of austenitic stainless steel. Application to IASCC of internals reactor core vessels

    International Nuclear Information System (INIS)

    The surface conditions of the 316L screw connecting vessel internals of the primary circuit of PWR (pressurized water reactor) corresponds to a grinding condition. These screws are affected by the IASCC (Irradiation Assisted Stress Corrosion Cracking). Initiation of cracking depends on the surface condition but also on the external oxidation and interactions of oxide layer with the deformation bands. The first objective of this study is to point the influence of surface condition on the growth kinetic of oxide layer, and the surface reactivity of 304, 316 stainless steel grade exposed to PWR primary water at 340 C. The second objective is to determine influence of strain localization on the SCC of austenitic stainless steels in PWR primary water. Indeed, the microstructure of irradiated 304, 316 grades correspond to a localized deformation in deformation bands free of radiation defects. In order to reproduce that microstructure without conducting irradiations, low cycle fatigue tests at controlled stain amplitude are implemented for the model material of the study (A286 austenitic stainless steel hardened by the precipitation of phase γ'Ni3(Ti, Al)). During the mechanical cycling (after the first hardening cycles), the precipitates are dissolved in slip bands leading to the localization of the deformation. Once the right experimental conditions in low cycle fatigue obtained (for localized microstructure), interactions oxidation / deformation bands are studied by oxidizing pre deformed samples containing deformation bands and non deformed samples. The tensile tests at a slow strain rate of 8 x 10-8 /s are also carried out on pre deformed samples and undeformed samples. The results showed that surface treatment induces microstructural modifications of the metal just under the oxide layer, leading to slower growth kinetics of the oxide layer. However, surface treatment accelerates development of oxides penetrations in metal under the oxide layer. As example, for

  5. Spiritual Bypass: A Preliminary Investigation

    Science.gov (United States)

    Cashwell, Craig S.; Glosoff, Harriet L.; Hammond, Cheree

    2010-01-01

    The phenomenon of spiritual bypass has received limited attention in the transpersonal psychology and counseling literature and has not been subjected to empirical inquiry. This study examines the phenomenon of spiritual bypass by considering how spirituality, mindfulness, alexithymia (emotional restrictiveness), and narcissism work together to…

  6. Effect of Dextrose-Crystalloid Priming Solution on Fluid Requirements and Urine Output During Cardiopulmonary Bypass

    OpenAIRE

    Metz, Samuel; Hacker, Jerriann

    1986-01-01

    We examined the influence of the addition of dextrose to crystalloid cardiopulmonary bypass priming solution. Ten patients received only lactated Ringer's solution during the perioperative period and as their cardiopulmonary bypass priming solution, while ten others, managed identically in all other respects, received only 5% dextrose in lactated Ringer's solution (D 5LR). During cardiopulmonary bypass, patients who did not receive glucose required more supplementary fluid (20.0 vs 2.2 ml Kg−...

  7. Cardiopulmonary bypass in pregnancy

    Directory of Open Access Journals (Sweden)

    Mukul Chandra Kapoor

    2014-01-01

    Full Text Available Cardiac surgery carried out on cardiopulmonary bypass (CPB in a pregnant woman is associated with poor neonatal outcomes although maternal outcomes are similar to cardiac surgery in non-pregnant women. Most adverse maternal and fetal outcomes from cardiac surgery during pregnancy are attributed to effects of CPB. The CPB is associated with utero-placental hypoperfusion due to a number of factors, which may translate into low fetal cardiac output, hypoxia and even death. Better maternal and fetal outcomes may be achieved by early pre-operative optimization of maternal cardiovascular status, use of perioperative fetal monitoring, optimization of CPB, delivery of a viable fetus before the operation and scheduling cardiac surgery on an elective basis during the second trimester.

  8. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    OpenAIRE

    Катюхин, Лев Николаевич

    2014-01-01

    It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin) and occlusion (PbCl2) of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small di...

  9. The influence of vessel movements on the energy expenditure of fishermen in relation to activities and occupational tasks on board

    OpenAIRE

    Breidahl, Tomas; Christensen, Michael; Jepsen, Jørgen Riis; Omland, Øyvind

    2015-01-01

    Background: Previous studies of professional fishing activities have indicated that vessel movements correlate to fishermen’s energy expenditure. We have previously demonstrated that even in calm weather, the heel and pitch significantly increase the fishermen’s energy expenditure, ignoring the activities carried out on board. This continuation of the study goes further by exploring the relation between the exposure to the ship’s movements and the fishermen’s energy expenditure during various...

  10. Current status of coronary artery bypass surgery

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin

    2009-01-01

    @@ Surgical revascularization for atherosclerotic heart disease, also called coronary artery bypass grafting (CABG), was first performed in 1962, and is one of the great achievements in medicine. Relief of angina, improvement of exercise tolerance, and the realization of survival benefit have been documented.1 CABG has been used in multi-vessel disease and left main stenosis for over 40 years.2 In the last two decades the mortality of CABG has decreased to less than 2% despite an aging population with increased risk factors. However, percutaneous coronary intervention (PCI), especially with drug-eluting stents, has been challenging CABG, While PCI has improved, CABG has also progressed with better peri-operative management, a higher use of arterial grafting, off-pump surgery, and improved techniques with minimally invasive surgical options.3,4

  11. Influence of the Target Vessel on the Location and Area of Maximum Skin Dose during Percutaneous Coronary Intervention

    International Nuclear Information System (INIS)

    Background: A number of cases involving radiation-associated patient skin injury attributable to percutaneous coronary intervention (PCI) have been reported. Knowledge of the location and area of the patient's maximum skin dose (MSD) in PCI is necessary to reduce the risk of skin injury. Purpose: To determine the location and area of the MSD in PCI, and separately analyze the effects of different target vessels. Material and Methods: 197 consecutive PCI procedures were studied, and the location and area of the MSD were calculated by a skin-dose mapping software program: Caregraph. The target vessels of the PCI procedures were divided into four groups based on the American Heart Association (AHA) classification. Results: The sites of the MSD for AHA no.1-3, AHA no.4, and AHA no.11-15 were located mainly on the right back skin, the lower right or center back skin, and the upper back skin areas, respectively, whereas the MSD sites for the AHA no. 5-10 PCI were widely spread. The MSD area for the AHA no. 4 PCI was larger than that for the AHA no. 11-15 PCI (P<0.0001). Conclusion: Although the radiation associated with PCI can be widely spread and variable, we observed a tendency regarding the location and area of the MSD when we separately analyzed the data for different target vessels. We recommend the use of a smaller radiation field size and the elimination of overlapping fields during PCI

  12. Influence of the Target Vessel on the Location and Area of Maximum Skin Dose during Percutaneous Coronary Intervention

    Energy Technology Data Exchange (ETDEWEB)

    Chida, K.; Fuda, K.; Kagaya, Y.; Saito, H.; Takai, Y.; Kohzuki, M.; Takahash i, S.; Yamada, S.; Zuguchi, M. [Dept. of Radiological Technology, School of Heal th Sciences, Faculty of Medicine, Tohoku Univ., Sendai (Japan)

    2007-10-15

    Background: A number of cases involving radiation-associated patient skin injury attributable to percutaneous coronary intervention (PCI) have been reported. Knowledge of the location and area of the patient's maximum skin dose (MSD) in PCI is necessary to reduce the risk of skin injury. Purpose: To determine the location and area of the MSD in PCI, and separately analyze the effects of different target vessels. Material and Methods: 197 consecutive PCI procedures were studied, and the location and area of the MSD were calculated by a skin-dose mapping software program: Caregraph. The target vessels of the PCI procedures were divided into four groups based on the American Heart Association (AHA) classification. Results: The sites of the MSD for AHA no.1-3, AHA no.4, and AHA no.11-15 were located mainly on the right back skin, the lower right or center back skin, and the upper back skin areas, respectively, whereas the MSD sites for the AHA no. 5-10 PCI were widely spread. The MSD area for the AHA no. 4 PCI was larger than that for the AHA no. 11-15 PCI (P<0.0001). Conclusion: Although the radiation associated with PCI can be widely spread and variable, we observed a tendency regarding the location and area of the MSD when we separately analyzed the data for different target vessels. We recommend the use of a smaller radiation field size and the elimination of overlapping fields during PCI.

  13. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting

    International Nuclear Information System (INIS)

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  14. A comparative study of mini-sternotomy and full-sternotomy for off-pump coronary artery bypass grafting in triple-vessel disease%胸骨下段小切口和全胸骨切口OPCABG治疗三支血管病变对比研究

    Institute of Scientific and Technical Information of China (English)

    顾松; 苏丕雄; 刘岩; 张希涛; 颜钧; 安向光; 高杰; 辛悦

    2016-01-01

    目的 对比研究胸骨下段"L"形小切口微创不停跳冠状动脉旁路移植手术(OPCABG)与常规OPCABG治疗冠心病三支病变的可行性、有效性和安全性.方法 2013年8月至12月期间160例冠状动脉三支血管病变患者,按区组随机化分组为经胸骨下段小切口OPCABG、全胸骨切口OPCABG两组,每组80例.由同一术者实施手术,术后随访.结果 两组围手术期均无死亡,无术中中转体外循环.两组平均旁路血管数量、新发房颤例数差异无统计学意义(P>0.05).与全胸骨切口组相比,胸骨下段小切口组的平均手术时间、左乳内动脉采集时间、气管插管时间、胸骨切口长度、ICU停留时间、住院天数等指标明显优于前者.另外,胸骨下段小切口组95.0%(76/80)保持了左侧胸膜的完整性,高于全胸骨切口组(75.0%,60/80).胸骨下段小切口组术后24 h心包纵隔引流量为(294.22±124.71) ml,明显少于全胸骨组(407.80±146.97) ml,差异有统计学意义(P=0.04).胸骨下段小切口组输血5例(6.3%),全胸骨组56例(70.0%).术后6个月所有患者均接受冠状动脉CT检查,两组各有4例大隐静脉旁路血管闭塞(6个月通畅率95.0%).随访12~ 16个月期间无患者死亡.结论 经胸骨下段小切口OPCABG手术不增加手术病死率及并发症发生率,避免了全胸骨切开,具有脱机拔管早、ICU停留时间短、输血少、住院天数少、恢复快等优势.经胸骨下段小切口OPCABG手术治疗三支血管病变有良好的可行性、有效性及安全性,是微创冠脉旁路移植治疗三支血管病变的有效方法.%Objective Evaluated the feasibility, validity, and safety of mini-sternotomy off-pump coronary artery bypass grafting for triple-vessel disease.Methods One hundred and sixty patients with triple-vessel coronary artery disease were randomly assigned to undergo OPCABG with mini-sternotomy or full-sternotomy.All operations were performed by the same

  15. Heart bypass surgery - minimally invasive

    Science.gov (United States)

    ... MIDCAB; Robot assisted coronary artery bypass; RACAB; Keyhole heart surgery ... To perform this surgery: The heart surgeon will make a 3- to 5-inch-long surgical cut in the left part of your chest between your ribs ...

  16. The influence of the neutron spectrum on the embrittlement of the pressure-vessel steels of the reactors

    International Nuclear Information System (INIS)

    The main purposes of this thesis are: - to point out the spectral effects on the radiation embrittlement of the pressure-vessel steels (A 508-Class 3). - to discern among the damage models proposed, using as gauge of exposure, the one that gives the best approach of the spectral effects observed between different irradiation locations. A simulated vessel-wall environment (called ''special location'') was constructed in the ''Melusine'' reactor of ''Centre d'Etudes Nucleaires de Grenoble'' that provided for measurements of steel embrittlement increase on Charpy-V notch samples and neutron flux detector activations as well as two other additionnal standard locations. Neutron spectra for these locations were calculated using Discrete Ordinate Transport Codes (ANISN and DOT 3.5.). Six campaigns of measurements of neutron spectrum by multiple foils activations were performed. Good agreement with results obtained from the calculations and the measurements were observed. The measured increases in steel transition temperature from the experimental locations revealed an important spectrum effect between the standard and special locations. If the data are expressed in (phi.t) > 1 MeV, this effect is about 50%. None of the tested damage models (displacement zones, Lindhard model, ...) does represent the observed effects

  17. The Influence of Dome Size, Parent Vessel Angle, and Coil Packing Density on Coil Embolization Treatment in Cerebral Aneurysms

    Science.gov (United States)

    Frakes, David H.; Indahlastari, Aprinda; Ryan, Justin; Babiker, M. Haithem; Nair, Priya; Parthas, Varsha

    2013-11-01

    Intracranial aneurysms (ICAs) are dilated cerebral blood vessels. Treating ICAs effectively prior rupture is crucial since their association with 45% mortality rate. Embolic coiling is the most effective ICA treatment. Series of embolic coils are deployed into the aneurysm with the intent of reaching a sufficient packing density (PD) to help seal off the ICA from circulation. While coiling is effective, treatment failures have been associated with basilar tip aneurysms (BTAs), perhaps because of their geometry. The aim of this study was to examine the effect of dome size, parent vessel (PV) angle, and PD on intraaneurysmal (IA) velocity, crossneck (CN) flow and low wall shear stress (WSS) area using simulations and experiments in idealized BTA models. IA velocity and CN flow decreased after coiling, while low WSS area increased. With increasing PD, IA velocity and CN flow were further reduced, but low WSS area had a minimal change. Coil PD had the greatest impact on post-treatment flow while dome size had a greater impact than PV angle. Overall, the role of aneurysmal geometries may vary depending on treatment goal and timing e.g., high coil PD may reduce IA velocity more effectively during early aneurysmal growth when the dome size is small. Funded by the American Heart Association.

  18. The influence of selected containment structures on debris dispersal and transport following high pressure melt ejection from the reactor vessel

    International Nuclear Information System (INIS)

    High pressure expulsion of molten core debris from the reactor pressure vessel may result in dispersal of the debris from the reactor cavity. In most plants, the cavity exits into the containment such that the debris impinges on structures. Retention of the debris on the structures may affect the further transport of the debris throughout the containment. Two tests were done with scaled structural shapes placed at the exit of 1:10 linear scale models of the Zion cavity. The results show that the debris does not adhere significantly to structures. The lack of retention is attributed to splashing from the surface and reentrainment in the gas flowing over the surface. These processes are shown to be applicable to reactor scale. A third experiment was done to simulate the annular gap between the reactor vessel and cavity wall. Debris collection showed that the fraction of debris exiting through the gap was greater than the gap-to-total flow area ratio. Film records indicate that dispersal was primarily by entrainment of the molten debris in the cavity. 29 refs., 36 figs., 11 tabs

  19. Influence of INCONEL 625 composition on the activation characteristics of the vacuum vessel of experimental fusion tokamaks

    International Nuclear Information System (INIS)

    The radioactive inventory, the decay heat and the contact dose rate of permanent components such as the vacuum vessel of two experimental fusion tokamaks, the compact IGNITOR-ULT and the ITER-EDA fusion machines, are evaluated by using the ENEA-Bologna integrated methodology. The vacuum vessel material considered is the INCONEL 625. The neutron flux is calculated using the VITAMIN-C 171-group library, based on EFF-2 data and the 1-D transport code XSDRNPM in the S8-P3 approximation. The ANITA-2 code, using updated cross sections and decay data libraries based on EAF-3 and IRDF90 evaluation files is used for activation calculations. The fusion neutron source has been normalised to a neutron first wall load of 2 MW/m2 and 1 MW/m2 for IGNITOR-ULT and ITER, respectively. The material irradiation have been described by multistep time histories, resulting in the designed total fluence. Variations in the composition of INCONEL 625 have been assessed and their impact on the activation characteristics are discussed, also from the point of view of waste disposal. (orig.)

  20. Assessment of extracranial-intracranial bypass patency with 64-slice multidetector computerized tomography angiography

    International Nuclear Information System (INIS)

    Extracranial-intracranial (EC/IC) bypass is a useful procedure for the treatment of cerebral vascular insufficiency or complex aneurysms. We explored the role of multidetector computed tomography angiography (MDCTA), instead of digital subtraction angiography (DSA), for the postoperative assessment of EC/IC bypass patency. We retrospectively analyzed a consecutive series of 21 MDCTAs from 17 patients that underwent 25 direct or indirect EC/IC bypass procedures between April 2003 and November 2007. Conventional DSA was available for comparison in 13 cases. MDCTA used a 64-slice MDCT scanner (Aquilion 64, Toshiba). The proximal and distal patencies were analyzed independently on MDCTA and DSA by a neuroradiologist and a neurosurgeon. The bypass was considered patent when the entire donor vessel was opacified without discontinuity from proximal to distal ends and was visibly in contact with the recipient vessel. MDCTA depicted the patency status in every patient. Bypasses were patent in 22 cases, stenosed in one, and occluded in two. DSA always confirmed the results of the MDCTA (sensitivity = 100%, 95% CI = 0.655-1.0; specificity 100%, 95% CI = 0.05-1.0). MDCTA is a non-invasive and accurate exam to assess the postoperative EC/IC bypass patency and is a promising technique in routine follow-up. (orig.)

  1. Bypass Rewiring and Robustness of Complex Networks

    CERN Document Server

    Park, Junsang

    2016-01-01

    A concept of bypass rewiring is introduced and random bypass rewiring is analytically and numerically investigated with simulations. Our results show that bypass rewiring makes networks robust against removal of nodes including random failures and attacks. Especially, random bypass rewiring connects all nodes except the removed nodes on an even degree infinite network and makes the percolation threshold $0$ for arbitrary occupation probabilities. In our example, the even degree network is more robust than the original network with random bypass rewiring while the original network is more robust than the even degree networks without random bypass. We propose a greedy bypass rewiring algorithm which guarantees the maximum size of the largest component at each step, assuming which node will be removed next is unknown. The simulation result shows that the greedy bypass rewiring algorithm improves the robustness of the autonomous system of the Internet under attacks more than random bypass rewiring.

  2. Percutaneous coronary intervention versus coronary-artery bypass grafting for severe coronary artery disease

    OpenAIRE

    Serruys, Patrick; Morice, Marie-Claude; Kappetein, Arie Pieter; Colombo, Antonio; Holmes, David; Mack, Michael; Stahle, E.; Feldman, Ted; Brand, Marcel, van den; Bass, Eric; Dyck, Nic; Leadly, Katrin; Dawkins, Keith; Mohr, Friedrich

    2009-01-01

    textabstractBACKGROUND Percutaneous coronary intervention (PCI) involving drug-eluting stents is increasingly used to treat complex coronary artery disease, although coronary-artery bypass grafting (CABG) has been the treatment of choice historically. Our trial compared PCI and CABG for treating patients with previously untreated three-vessel or left main coronary artery disease (or both). METHODS We randomly assigned 1800 patients with three-vessel or left main coronary artery disease to und...

  3. 微创胸骨下段小切口不停跳冠状动脉旁路移植治疗三支血管病变%Mini-sternotomy for off-pump coronary artery bypass grafting in triple-vessel disease

    Institute of Scientific and Technical Information of China (English)

    苏丕雄; 顾松; 刘岩; 张希涛; 颜钧; 安向光; 高杰; 辛悦

    2015-01-01

    植病例.全组手术时间(205.42 ±32.17) min,旁路移植血管(3.01±0.47)支,LIMA至LAD旁路80支,至右冠状动脉(RCA)及其分支70支,到左回旋支(LCX)及其分支65支,到中间支26支.62例(77.5%,62/80)未输血.术后(20.41±11.08)h拔除气管插管,监护(4.23±2.11)天.术后(11.50 ±3.21)天治愈出院.无围手术期心肌梗死或再次开胸止血,无伤口感染或胸骨哆开等严重并发症.术后新发心房颤动28例.1例80岁女患者,术后4天因睡眠呼吸暂停综合征、呼吸道阻塞引起呼吸心脏骤停死亡.全部出院患者随访3~6个月,无心绞痛复发和死亡,2例因心功能不全、肺部感染再次入院.结论 胸骨下段微创“L”形小切口不停跳冠状动脉旁路移植术治疗三支血管病变有效、安全,是微创旁路移植治疗三支血管病变的有效方法.此技术能完成包括回旋支在内的所有冠状动脉靶血管的旁路移植吻合,合理选择病例和术者,足够的全胸骨劈开不停跳冠状动脉旁路移植手术经验是确保手术成功的关键.%Objective To evaluate the feasibility and safety of a novel,minimally invasive surgical approach with ministernotomy for off-pump coronary revascularization in triple-vessel disease,propose the operational indications and key technique.Methods Between March 2013 and Jul 2013,a series of 80 patients with triple-vessel disease underwent a minimally invasive direct coronary artery bypass through the mini-sternotomy,which included the lower half of the mini-sternotomy (reversed L-shaped division of the sternum) and the off-pump beating heart technique.Results The operations were completed without conversion to full sternotomy or to cardiopulmonary bypass.There were only one death in the perioperative period.The mean length of the skin incision was(14.96 ± 1.42) cm.The mean operative time was(205.42 ±32.17) minutes.The mean number of grafts was (3.01 ± 0.47).The pulsatile index was 3.2 ± 1.8.Hemoglobin levels slightly decreased from (124

  4. Direct ECC bypass phenomena in the MIDAS test facility during LBLOCA reflood phase

    International Nuclear Information System (INIS)

    This paper describes the experimental results of ECC Direct Bypass Phenomena in the downcomer during the late reflood phase of LBLOCA of the reactor that adopts Direct Vessel Injection as a ECC system. The experiments have been performed in MIDAS test facility using superheated steam and water. The test condition was determined, based on the preliminary analysis of TRAC code, from modified linear scaling method of 1/4.93 length scale. To measure the direct bypass fraction according to the nozzle location, separate effect tests have been performed in case of DVI-4(farthest from broken cold leg) injection, DVI-2(closest to broken cold leg) injection, and DVI-2 and 4 injection, respectively. Also the test was carried out varying the steam flow rate greatly to investigate the effect of steam flow rate on the direct bypass fraction of ECC water. Test results show that the direct bypass fraction of ECC water depends significantly on the injected steam mass flow rate. DVI-4 tests show that the direct bypass fraction increases drastically as the steam flow rate increases. However, in DVI-2 test most of the injected ECC water penetrates into lower downcomer. The direct bypass characteristic in each of DVI-2 and DVI-4 tests is reflected into the direct bypass characteristic curve of DVI-2 and 4 test. The steam condensation reaches to the theoretically allowable maximum value

  5. Direct ECC bypass phenomena in the MIDAS test facility during LBLOCA reflood phase

    Energy Technology Data Exchange (ETDEWEB)

    Yun, B. J.; Kweon, T. S.; Ah, D. J.; Ju, I. C.; Song, C. H.; Park, J. K. [KAERI, Taejon (Korea, Republic of)

    2001-10-01

    This paper describes the experimental results of ECC Direct Bypass Phenomena in the downcomer during the late reflood phase of LBLOCA of the reactor that adopts Direct Vessel Injection as a ECC system. The experiments have been performed in MIDAS test facility using superheated steam and water. The test condition was determined, based on the preliminary analysis of TRAC code, from modified linear scaling method of 1/4.93 length scale. To measure the direct bypass fraction according to the nozzle location, separate effect tests have been performed in case of DVI-4(farthest from broken cold leg) injection, DVI-2(closest to broken cold leg) injection, and DVI-2 and 4 injection, respectively. Also the test was carried out varying the steam flow rate greatly to investigate the effect of steam flow rate on the direct bypass fraction of ECC water. Test results show that the direct bypass fraction of ECC water depends significantly on the injected steam mass flow rate. DVI-4 tests show that the direct bypass fraction increases drastically as the steam flow rate increases. However, in DVI-2 test most of the injected ECC water penetrates into lower downcomer. The direct bypass characteristic in each of DVI-2 and DVI-4 tests is reflected into the direct bypass characteristic curve of DVI-2 and 4 test. The steam condensation reaches to the theoretically allowable maximum value.

  6. One-week postoperative patency of lower extremity in situ bypass graft comparing epidural and general anesthesia

    DEFF Research Database (Denmark)

    Wiis, Julie Therese; Jensen-Gadegaard, Peter; Altintas, Ümit; Seidelin, Claus; Martusevicius, Robertas; Mantoni, Teit

    2014-01-01

    under epidural (n = 386) or general (n = 499) anesthesia. Thirty-day mortality (3.4% for epidural anesthesia versus 4.4% general anesthesia; P = 0.414) and comorbidity were comparable in the 2 groups. Graft occlusion within 7 days after surgery was reported in 93 patients, with a similar incidence in...... the epidural (10.1%) and general (10.8%) anesthesia groups (P = 0.730). When examining a subgroup of patients (n = 242) exposed to surgery on smaller vessels (femorodistal in situ bypass procedures, n = 253), the incidence of graft occlusion was also similar in the 2 groups at 14.0% and 9.......4%, respectively (P = 0.262). CONCLUSION: This retrospective study has shown that when graft patency is evaluated 7 days after surgery, anesthetic choice (epidural or general anesthesia) does not influence outcome....

  7. Technology Solutions Case Study: Preventing Thermal Bypass

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-10-01

    This project highlights the importance of continuous air barriers in full alignment with insulation to prevent thermal bypasses and achieve high energy performance, and recommends use of ENERGY STAR's Thermal Bypass Inspection Checklist.

  8. Multimodality imaging of coronary artery bypass grafts

    OpenAIRE

    Salm, Liesbeth Pauline

    2006-01-01

    This thesis describes multiple imaging modalities to examine coronary artery bypass grafts, and the research which was performed to further develop noninvasive imaging techniques to detect stenoses in native coronary arteries and bypass grafts in patients who experienced recurrent chest pain after coronary artery bypass grafting (CABG).

  9. Stone vessels

    Czech Academy of Sciences Publication Activity Database

    Maříková Vlčková, Petra

    Prague : Charles University in Prague, 2010 - (Bárta, M.; Coppens, F.; Vymazalová, H.), s. 108-149 ISBN 978-80-7308-325-0 Institutional research plan: CEZ:AV0Z80020508 Keywords : stone vessels * Abusir South * Early Dynastic period * Old Kingdom * non-royal funerary architecture Subject RIV: AC - Archeology, Anthropology, Ethnology

  10. 胃旁路术对血糖的影响及其机制%Influence of gastric bypass surgery on fasting blood-glucose in type 2 diabetic rats

    Institute of Scientific and Technical Information of China (English)

    史逸华; 郑志坚; 戴灵波; 宋军; 江玲雅

    2013-01-01

    Objective To investigate the influence of gastric bypass surgery on fasting blood- glucose (FBG) levels in type 2 diabetic rats. Methods Forty rates were randomly divided into 4 groups with 10 in each groups:type 2 diabetes mel itus were induced by injection of stretozotocin in DO and DC group, gastric bypass operation was performed in DO and NO groups and sham operation was performed in DC and NC groups. The FBG levels were determined before operation and 72h, 1, 4 and 8 weeks after operation. The tissue sections were HE- stained and examined histopathological y. Results There were no signif-icant differences in FBG levels before operation between DO and DC groups or between NO and NC groups (P>0.05). FBG levels in DO group gradual y declined after operation and were lower than those before operation (P0.05). The inter- group and intra- group differences of FPG levels in NO and NC groups were not statistical y sig-nificant(P>0.05). HE staining showed that there was regeneration of pancreas islets and the morphology was similar to the nor-mal in DO group at 8 weeks after operation. Conclusion Gastric bypass operation can reduce the FBG levels in type 2 diabetic rats, which is associated with the regeneration of pancreas islets.%目的研究胃旁路术(GBP)对糖尿病大鼠血糖的控制效果以及对胰岛细胞的影响。方法采用链脲佐菌素建立糖尿病SD大鼠模型(20只),随机分为糖尿病手术组(DO组)和糖尿病对照组(DC组),另取20只非糖尿病大鼠随机分为正常手术组(NO组)和正常对照组(NC组)。DO组和NO组大鼠行GBP,DC组和NC组大鼠行假手术,分别检测各组大鼠术前、术后72h,1、4和8周空腹血糖水平。术后8周,取胰腺组织行HE染色和免疫荧光检查,观察组织学变化。结果术前DO组与DC组以及NC组与NO组大鼠空腹血糖均无统计学差异(均P>0.05)。DO组大鼠术后空腹血糖进行性下降(均P<0.05

  11. Interventions in Infrainguinal Bypass Grafts

    International Nuclear Information System (INIS)

    The interventional radiologist plays an important role in the detection and prevention of infrainguinal bypass failure. Early detection and evaluation of flow-limiting lesions effectively preserve graft (venous bypass and polyester or expanded polytetrafluoroethylene bypass) patency by identifying stenoses before occlusion occurs. Delay in treatment of the at-risk graft may result in graft failure and a reduced chance of successful revascularization. For this reason, surveillance protocols form an important part of follow-up after infrainguinal bypass surgery. As well as having an understanding of the application of imaging techniques including ultrasound, MR angiography, CT angiography and digital subtraction angiography, the interventional radiologist should have detailed knowledge of the minimally invasive therapeutic options. Percutaneous transluminal angioplasty (PTA), or alternatively cutting balloon angioplasty, is the interventional treatment of choice in prevention of graft failure and occlusion. Further alternatives include metallic stent placement, fibrinolysis, and mechanical thrombectomy. Primary assisted patency rates following PTA can be up to 65% at 5 years. When the endovascular approach is unsuccessful, these therapeutic options are complemented by surgical procedures including vein patch revision, jump grafting, or placement of a new graft

  12. Efficiency Biliopancreatic bypass surgery in bulimia nervosa

    Directory of Open Access Journals (Sweden)

    Yu I Yashkov

    2008-06-01

    Full Text Available A clinical significance in the treatment of bulimia nervosa patients with morbid obesity had already been raised [10, 13], but we did not find publications on the effectiveness of bariatric surgery in these cases. There is also information about the possibility of applying the operation bilio-pancreatic bypass, effective in patients with morbid obesity with uncontrolled eating behavior for the treatment of patients with anorexia BILIM not suffering from morbid obesity. In this article the data of clinical observation of a small sample of patients. As a result, the treatment of these patients found that severe nervous BILIM can be seen as a latent form of morbid obesity. The choice of treatment should depend not only on the initial body weight of the patient, but also on the severity of the nervous BILIM. Unsuccessful attempts at organized-balanced, conservative treatment of patients with severe bulimia nervosa may be considered a variant of surgical treatment, while bilio-pancreatic bypass surgery is considered as the most preferred operation, compared with the installation of the gastric balloon and others. All candidates for surgical treatment of obesity must identify clinical signs of bulimia nervosa, as this may influence the choice of method of operation. Further study of the role of hyperinsulinemia, secretion of ghrelin, leptin, intestinal peptide may contribute to the elucidation of the true causes of bulimia nervosa, probably has a similar origin with morbid obesity.

  13. Intraarterial digital subtraction angiography of aortofemoral bypasses

    International Nuclear Information System (INIS)

    In a retrospective study, 214 digital subtraction angiography (DSA) examinations of aortofemoral and femorocrural bypasses were reviewed. In 90% of cases intravenous DSA was diagnostic for aortofemoral bypasses, and in 95% of cases intrarterial DSA angiograms of excellent image quality were obtained. In 82% arterial stenoses proximal to the bypass, in 62% stenoses distal to the bypass, and in only 15% stenoses involving the bypass itself could be detected. In 54% the bypass was regularly perfused. In 26% a complete occlusion could be seen. All angiograms were obtained after infusion of the low-osmolar nonionic contrast medium Iopromide, 150mg/ml. All examinations were painless, and no heat-induced motion artifacts were registered. No disturbances of vital signs were observed. DSA with a nonionic low-osmolarity contrast medium (Iopromide) is a safe and reliable technique for the examination of all surgical aortofemoral bypasses

  14. Bypass materials in vascular surgery

    Directory of Open Access Journals (Sweden)

    Willich, Stephan N.

    2006-03-01

    Full Text Available Introduction: Arteriosclerotic changes can lead to circulatory disturbances in various areas of the human vascular system. In addition to pharmacological therapy and the management of risk factors (e. g. hypertension, diabetes, lipid metabolism disorders, and lifestyle, surgical interventions also play an important role in the treatment of arteriosclerosis. Long-segment arterial occlusions, in particular, can be treated successfully with bypass sur-gery. A number of different materials are available for this type of operation, such as autologous vein or pros-thetic grafts comprised of polytetrafluoroethylene (PTFE or Dacron®. Prosthetic materials are used especially in the treatment of peripheral artery disease, such as in aortoiliac or femoropopliteal bypass surgery. The present report will thus focus on this area in order to examine the effectiveness of different bypass materials. Among the efforts being made to refine the newly introduced DRG system in Germany, analysing the different bypass materials used in vascular surgery is particularly important. Indeed, in its current version the German DRG system does not distinguish between bypass materials in terms of reimbursement rates. Differences in cost structures are thus of especial interest to hospitals in their budget calculations, whereas both private and statutory health insurance funds are primarily interested in long-term results and their costs. Objectives: The goal of this HTA is to compare the different bypass materials used in vascular surgery in terms of their medical efficiency and cost-effectiveness, as well as with regard to their ethical, social and legal implications. In addition, this report aims to point out the areas in which further medical, epidemiological and health economic research is still needed. Methods: Relevant publications were identified by means of a structured search of databases accessed through the German Institute of Medical Documentation and Information

  15. Application of digital subtraction angiography in disease of large cardiac vessel

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, Jun; Sone, Shusuke; Morimoto, Shizuo; Ikezoe, Junpei; Higashibara, Tokuro; Hanayama, Masayuki

    1983-06-01

    Digital subtraction angiography (DSA) was performed in 31 cases of disease of large cardiac vessel. DSA was useful for the diagnosis of aortic aneurysm and malformation of large vessels, follow-up after A-C bypass operation and Blalock's shunt operation for tetralogy of Fallot and as an adjuvant modality in cardiac catheterization.

  16. Application of digital subtraction angiography in disease of large cardiac vessel

    International Nuclear Information System (INIS)

    Digital subtraction angiography (DSA) was performed in 31 cases of disease of large cardiac vessel. DSA was useful for the diagnosis of aortic aneurysm and malformation of large vessels, follow-up after A-C bypass operation and Blalock's shunt operation for tetralogy of Fallot and as an adjuvant modality in cardiac catheterization. (Chiba, N.)

  17. Blood flow modeling for patient-specific bypass surgery in lower-limb arteries

    OpenAIRE

    Willemet, Marie

    2012-01-01

    Every day in Belgium, at least one or two people will undergo a bypass surgery in the lower-limb arteries. This medical procedure consists of replacing an occluded section of the leg arteries with an artificial vessel, in order to allow blood to flow downwards of this blockage. Even though this intervention is very common, failure of this treatment within five years reaches up to 60%. In order to improve our understanding of the causes of bypass failure, one approach is to study the local hem...

  18. Potential effects of ex-vessel molten core debris interactions on boiling water reactor containment integrity

    International Nuclear Information System (INIS)

    There is a steadily increasing awareness of the highly plant-specific nature of reactor safety issues. This awareness is reflected in the increasing number of research programs focused on problems limited to specific reactor or containment types. This report is limited to NRC-sponsored research on accident phenomena that may affect the integrity of boiling water reactor containment systems arising out of ex-vessel interactions of molten core debris in the reactor cavity. Some safety issues that are generic to all types of BWRs are discussed, these include: (1) effects of concrete composition, (2) dispersive effect of structures below the reactor vessel, (3) influence of unoxidized zirconium metal in the debris pool, (4) the influence of water in the reactor cavity on debris coolability and magnitude of the radiological source term, and (5) the nature of high-temperature condensed-phase chemistry and fission-product aerosol generation. Certain ex-vessel core-debris phenomena which may threaten the integrity of specific BWR containment designs include the following: (1) integrity of the BWR MARK-I steel pressure boundary, (2) potential for penetration of the MARK-II drywell floor and/or supression-pool bypass, and (3) possible failure of the MARK-III reactor support system due to thermal ablation of the reactor pedestal. Some recent experimental results derived from NRC-sponsored programs are also presented

  19. Mini cardiopulmonary bypass: Anesthetic considerations

    OpenAIRE

    Alsatli, Raed A.

    2012-01-01

    This review article is going to elaborate on the description, components, and advantages of mini-cardiopulmonary bypass (mini-CPB), with special reference to the anesthetic management and fast track anesthesia with mini-CPB. There are several clinical advantages of mini-CPB like, reduced inflammatory reaction to the pump, reduced need for allogenic blood transfusion and lower incidence of postoperative neurological complications. There are certainly important points that have to be considered...

  20. In Vivo Clearance of Alpha-1 Acid Glycoprotein Is Influenced by the Extent of Its N-Linked Glycosylation and by Its Interaction with the Vessel Wall

    Directory of Open Access Journals (Sweden)

    Teresa R. McCurdy

    2012-01-01

    Full Text Available Alpha-1 acid glycoprotein (AGP is a highly glycosylated plasma protein that exerts vasoprotective effects. We hypothesized that AGP’s N-linked glycans govern its rate of clearance from the circulation, and followed the disappearance of different forms of radiolabeled human AGP from the plasma of rabbits and mice. Enzymatic deglycosylation of human plasma-derived AGP (pdAGP by Peptide: N-Glycosidase F yielded a mixture of differentially deglycosylated forms (PNGase-AGP, while the introduction of five Asn to Gln mutations in recombinant Pichia pastoris-derived AGP (rAGP-N(5Q eliminated N-linked glycosylation. PNGase-AGP was cleared from the rabbit circulation 9-fold, and rAGP-N(5Q, 46-fold more rapidly than pdAGP, primarily via a renal route. Pichia pastoris-derived wild-type rAGP differed from pdAGP in expressing mannose-terminated glycans, and, like neuraminidase-treated pdAGP, was more rapidly removed from the rabbit circulation than rAGP-N(5Q. Systemic hyaluronidase treatment of mice transiently decreased pdAGP clearance. AGP administration to mice reduced vascular binding of hyaluronic acid binding protein in the liver microcirculation and increased its plasma levels. Our results support a critical role of N-linked glycosylation of AGP in regulating its in vivo clearance and an influence of a hyaluronidase-sensitive component of the vessel wall on its transendothelial passage.

  1. Influence of Modelling Options in RELAP5/SCDAPSIM and MAAP4 Computer Codes on Core Melt Progression and Reactor Pressure Vessel Integrity

    Directory of Open Access Journals (Sweden)

    Siniša Šadek

    2010-01-01

    Full Text Available RELAP5/SCDAPSIM and MAAP4 are two widely used severe accident computer codes for the integral analysis of the core and the reactor pressure vessel behaviour following the core degradation. The objective of the paper is the comparison of code results obtained by application of different modelling options and the evaluation of influence of thermal hydraulic behaviour of the plant on core damage progression. The analysed transient was postulated station blackout in NPP Krško with a leakage from reactor coolant pump seals. Two groups of calculations were performed where each group had a different break area and, thus, a different leakage rate. Analyses have shown that MAAP4 results were more sensitive to varying thermal hydraulic conditions in the primary system. User-defined parameters had to be carefully selected when the MAAP4 model was developed, in contrast to the RELAP5/SCDAPSIM model where those parameters did not have any significant impact on final results.

  2. Influence of High Aspect Ratio Vessel Cell Culture on TNF-Alpha, Insulin Secretion and Glucose Homeostasis in Pancreatic Islets of Langerhans from Wistar Furth Rats

    Science.gov (United States)

    Tobin, Brian W.a; Leeper-Woodford, Sandra K.

    1999-01-01

    The present studies were carried out to determine the influence of a ground based microgravity paradigm, utilizing the High Aspect Ratio Vessel (HARV) cell culture upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF-alpha) production of pancreatic islets of Langerhans. An additional aim was to elucidate alterations in insulin secretion and glucose utilization using the HARV low shear, gravity averaged vector, cell culture technique. Islets were isolated (1726 +/- 117, 150 micron islet equivalent units) from Wistar Furth rats and assigned to four treatment groups: 1) HARV, 2) HARV plus LPS, 3) static culture, 4) static culture plus LPS. Following 48 hours of culture, insulin concentration was increased in both HARV and static cultures (pcultures were assayed for TNF-alpha (L929 cytotoxicity assay) and was measured at selected time points for 48 hours. TNF-alpha was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (pculture (pcultures, suggesting a decreased reliance upon glucose as a metabolic substrate in the islets cultured in HARVS. In conclusion, the present studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF production in the microgravity HARV paradigm. Additionally, alterations in fuel homeostasis may be promulgated by HARV culture. The clinical and physiological significance of these observations remains to be determined.

  3. A study of the influence scan timing and depiction of blood vessel diameter in CE-3DMRA. Simulation by pulsatile flow

    International Nuclear Information System (INIS)

    In imaging using contrast-enhanced three-dimensional magnetic resonance angiography (CE-3DMRA), optimizing the delay time from the start of intravenous injection of contrast medium to the start of scanning has generally been an important concern when obtaining blood vessel images of good contrast. Recent methods of mechanically assessing the attainment of contrast medium injection include Smart-Prep and others. Another method is the Test Bolus, in which a small amount of contrast medium determines the timing of scan start, in quest of the time intensity curve. Because these methods are not necessarily satisfactory, the corrected method is used in clinical cases. In terms of how scan timing affects blood vessel depiction, no study has examined pulsatile flow, which is carried out by simulation. On the other hand, there are reports on data filling of k-space using imitation blood vessels on a computer and simple experimental equipment. This research examined experimentally blood vessel depiction according to scan timing and the diameter of blood vessels by using a systemic circulation simulator that incorporated hemodynamic circulation in which pulsatile flow is the same as that of a human body, using an artificial heart developed especially for MRI. It is thought that scan timing in CE-3DMRA affects the depiction of blood vessels for which the diameter of the blood vessel differs from the experimental result. Phase-encoding k-space data filling is the contrast-to-noise ratio (CNR) of each blood vessel irrespective of sequential and centric k-space ordering. The timing shift phenomenon, in which a blood vessel is so thin that the scan timing is overdue and shows a relatively high value, can occur. Moreover, that scan timing affects not only the diameter of a blood vessel but also depiction of the narrowing of a stenotic blood vessel or a branch blood vessel was demonstrated clinically and experimentally. Therefore, blood vessel depiction changes with scan timing, and

  4. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting; Die EKG-getriggerte 4-Zeilen-Spiral-CT des Herzens in der praeoperativen Bildgebung vor minimalinvasiver koronarer Bypass-Operation

    Energy Technology Data Exchange (ETDEWEB)

    Begemann, P.G.C.; Ittrich, H.; Koops, A.; Adam, G.; Weber, C. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Radiologisches Zentrum, Universitaetsklinikum, Hamburg (Germany); Arnold, M.; Detter, C.; Boehm, D.H.; Reichenspurner, H. [Universitaetsklinikum Hamburg-Eppendorf, Herzzentrum, Herz und Gefaesschirurgie, Hamburg (Germany)

    2005-08-01

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  5. Influence of climate on tree rings and vessel features in red oak and white oak growing near their northern distribution limit, southwestern Quebec, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Tardif, J.C.; Conciatori, F. [Winnipeg Univ., MB (Canada). Centre for Forest Interdisciplinary Research

    2006-09-15

    A study assessing the association between tree-ring descriptors, vessel series and climate change in white oak and red oak species was presented. Ten trees of each oak species were analyzed at a site in southern Quebec. For each species, 11 chronologies using vessel and ring width were developed and then compared. The potential for using vessel features in climate reconstructions was evaluated by comparing 4 regression models resulting from different combinations of variables: (1) ring width with 1 variable per species; (2) earlywood, latewood and ring width; (3) vessel variables; and (4) all chronologies. Results indicated that there was little difference between the 2 species. All vessel chronologies were associated with ring dimension, and did not reveal a unique climate signature. Growing season conditions were associated with latewood features, whereas those of the previous year were associated with earlywood features. All 4 models developed to reconstruct the July Canadian Drought Code (CDC) showed good predictive ability. Models using vessel variables did not improve estimations. Good reconstruction models were derived from earlywood, latewood, and ring-width chronologies. The results suggested that vessel chronologies have limited applications in dendroclimatology, and that vessel features are best used to identify event years recorded during the life of the trees. Vessel features in ring-porous species may also be used to decipher discontinuous signals related to tree growth in order to understand tree physiology. It was concluded that the vessel features provided no new information beyond that obtained from the much easier and cheaper measurement of ring width in paleoclimatic records. 56 refs., 3 tabs., 5 figs.

  6. Epicardial ultrasound in coronary artery bypass surgery

    OpenAIRE

    Budde, R.P.J.

    2005-01-01

    Chapter 1 Coronary artery bypass surgery (CABG) is traditionally performed via a median sternotomy approach on cardiopulmonary bypass (arrested heart). Since the mid 1990ties, beating heart, minimally invasive and even totally endoscopic CABG are (re)explored. In all approaches to CABG, the surgeon may face several intraoperative difficulties: 1. Localization of the target coronary artery for bypass grafting. 2. Selection of the optimal anastomotic site on the target coronary artery. 3. Asses...

  7. Influence of High Aspect Ratio Vessel Cell Culture on TNF-Alpha, Insulin Secretion and Glucose Homeostasis in Pancreatic Islets of Langerhans from Wistar Furth Rats

    Science.gov (United States)

    Tobin, Brian W.a; Leeper-Woodford, Sandra K.

    1999-01-01

    The present studies were carried out to determine the influence of a ground based microgravity paradigm, utilizing the High Aspect Ratio Vessel (HARV) cell culture upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF-alpha) production of pancreatic islets of Langerhans. An additional aim was to elucidate alterations in insulin secretion and glucose utilization using the HARV low shear, gravity averaged vector, cell culture technique. Islets were isolated (1726 +/- 117, 150 micron islet equivalent units) from Wistar Furth rats and assigned to four treatment groups: 1) HARV, 2) HARV plus LPS, 3) static culture, 4) static culture plus LPS. Following 48 hours of culture, insulin concentration was increased in both HARV and static cultures (pcultures were assayed for TNF-alpha (L929 cytotoxicity assay) and was measured at selected time points for 48 hours. TNF-alpha was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (pcells are present in islets and that LPS stimulates TNF secretion in isolated islets. A decrease in insulin concentration was demonstrated in the islet medium of the LPS stimulated HARV culture (pcultures, suggesting a decreased reliance upon glucose as a metabolic substrate in the islets cultured in HARVS. In conclusion, the present studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF production in the microgravity HARV paradigm. Additionally, alterations in fuel homeostasis may be promulgated by HARV culture. The clinical and physiological significance of these observations remains to be determined.

  8. EC-IC bypass for cavernous carotid aneurysms: An initial experience with twelve patients

    Science.gov (United States)

    Menon, G.; Jayanand, Sudhir; Krishnakumar, K.; Nair, S.

    2014-01-01

    Aims: Need for performing a bypass procedure prior to parent artery occlusion in patients with good cerebral vascular reserve is controversial. We analyze our experience of 12 giant internal carotid artery aneurysms treated with extracranial-intracranial (EC-IC) bypass and proximal artery occlusion. Materials and Methods: Retrospective analysis of the case records of all complex carotid aneurysms operated in our institute since January 2009. Results: The study included eleven cavernous carotid aneurysms and one large fusiform cervical carotid aneurysm reaching the skull base. Preoperative assessment of cerebral vascular reserve was limited to Balloon test occlusion with hypotensive challenge. Eleven patients who successfully completed a Balloon test occlusion (BTO) underwent low flow superficial temporal artery to middle cerebral artery (STA-MCA) bypass, while one patient with a failed BTO underwent a high flow bypass using a saphenous vein graft. Parent artery ligation was performed in all patients following the bypass procedure. Check angiogram revealed thrombosis of the aneurysm in all patients with a graft patency rate of 81.8%. We had one operative mortality, probably related to a leak from the anastomotic site. The only patient who had a high flow bypass developed contralateral hemispheric infarcts and remained vegetative. All the other patients had a good recovery and with a Glasgow outcome score of 5 at last follow-up. Conclusion: We feel that combining EC-IC bypass prior to parent vessel occlusion helps in reducing the risk of post operative ischemic complications especially in situations where a complete mandated cerebral blood flow studies are not feasible. PMID:25126123

  9. Epicardial ultrasound in coronary artery bypass surgery

    NARCIS (Netherlands)

    Budde, R.P.J.

    2005-01-01

    Chapter 1 Coronary artery bypass surgery (CABG) is traditionally performed via a median sternotomy approach on cardiopulmonary bypass (arrested heart). Since the mid 1990ties, beating heart, minimally invasive and even totally endoscopic CABG are (re)explored. In all approaches to CABG, the surgeo

  10. Atrial fibrillation post cardiac bypass surgery

    OpenAIRE

    Mostafa, Ashraf; EL-Haddad, Mohamed A.; Shenoy, Maithili; Tuliani, Tushar

    2012-01-01

    Atrial fibrillation occurs in 5-40% patients after coronary artery bypass graft surgery. Atrial fibrillation increases mortality and morbidity in the post-operative period. We sought to conduct a comprehensive review of literature focusing on pathophysiology, risk factors, prevention and treatment of post coronary artery bypass graft atrial fibrillation.

  11. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... going to thread that up to the patient’s bypass graft using X-ray, and there you are. So what we’re going to do is manipulate this catheter into actually the artery that leads to the arm, the subclavian, which is where the bypass comes off. Let me just saw it for ...

  12. Outflow distribution at the distal anastomosis of infrainguinal bypass grafts.

    Science.gov (United States)

    Fisher, R K; How, T V; Bakran, A; Brennan, J A; Harris, P L

    2004-03-01

    Outflow distribution at the distal anastomosis of infrainguinal bypass grafts remains unquantified in vivo, but is likely to influence flow patterns and haemodynamics, thereby impacting upon graft patency. This study measured the ratio of distal to proximal outflow in 30 patients undergoing infrainguinal bypass for lower limb ischaemia, using a flow probe and a transit-time ultrasonic flow meter. The mean outflow distribution was approximately 75% distal to 25% proximal, with above knee anastomoses having a greater proportion of distal flow (84%) compared to below knee grafts (73%). These in vivo flow characteristics differ significantly from those used in theoretical models studying flow phenomena (50:50 and/or 100:0), and should be incorporated into future research. PMID:14757463

  13. Coronary angiographies of patients with recurrent acute coronary syndrome following coronary artery bypass grafting

    Institute of Scientific and Technical Information of China (English)

    JIA Yu-he; YANG Yue-jin; WEI Yi-zhen; YAO Min; HU Sheng-shou

    2005-01-01

    @@ Coronary artery bypass grafting (CABG) is considered as a more complete means of revascularization than percutaneous coronary intervention (PCI). However, acute coronary syndrome (ACS) can still occur after CABG. The culprit vessel can be the graft vessel or the native vessel. Many questions remain unanswered in the Chinese literature regarding this topic: what are the short- and long-term pathological changes that induce ACS? Is there any difference between arterial and venous grafts with respect to the frequency of restenosis? Are there any patterns of ACS-related vessels in different periods after CABG? We aim to answer these fundamental questions by analyzing coronary angiographies of patients with recurrent ACS following CABG and provide evidence for reducing post-CABG restenosis.

  14. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  15. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit...

  16. In situ bypass og diabetes

    DEFF Research Database (Denmark)

    Jensen, Leif Panduro; Schroeder, T V; Lorentzen, J E

    1993-01-01

    From 1986 through to 1990 a total of 483 in situ bypass procedures were performed in 444 patients. Preoperative risk-factors were equally distributed among diabetic (DM) and non-diabetic (NDM) patients, except for smoking habits (DM:48%, NDM:64%, p = 0.002) and cardiac disease (DM:45%, NDM:29%, p...... = 0.005). Critical limb-ischaemia was more often present in diabetic than non-diabetic patients (DM:57%, NDM:36%, p = 0.0002). Diabetic patients had a significantly lower distal anastomosis than non-diabetic patients (p = 0.00001). There were no differences among diabetic and non-diabetic patients...... regarding three years primary and secondary patency (58% and 64% respectively), and regarding major amputations. However, the rate of minor amputations was higher in insulin-dependent compared with non-insulin-dependent diabetics, who in turn had a higher rate than non-diabetics (p

  17. Anesthesia for off-pump coronary artery bypass surgery

    Directory of Open Access Journals (Sweden)

    Thomas M Hemmerling

    2013-01-01

    Full Text Available The evolution of techniques and knowledge of beating heart surgery has led anesthesia toward the development of new procedures and innovations to promote patient safety and ensure high standards of care. Off-pump coronary artery bypass (OPCAB surgery has shown to have some advantages compared to on-pump cardiac surgery, particularly the reduction of postoperative complications including systemic inflammation, myocardial injury, and cerebral injury. Minimally invasive surgery for single vessel OPCAB through a limited thoracotomy incision can offer the advantage of further reduction of complications. The anesthesiologist has to deal with different issues, including hemodynamic instability and myocardial ischemia during aorto-coronary bypass grafting. The anesthesiologist and surgeon should collaborate and plan the best perioperative strategy to provide optimal care and ensure a rapid and complete recovery. The use of high thoracic epidural analgesia and fast-track anesthesia offers particular benefits in beating heart surgery. The excellent analgesia, the ability to reduce myocardial oxygen consumption, and the good hemodynamic stability make high thoracic epidural analgesia an interesting technique. New scenarios are entering in cardiac anesthesia: ultra-fast-track anesthesia with extubation in the operating room and awake surgery tend to be less invasive, but can only be performed on selected patients.

  18. Study of transient turbine shot without bypass in a BWR

    International Nuclear Information System (INIS)

    The study and analysis of operational transients are important for predicting the behavior of a system to short-terms events and the impact that would cause this transition. For the nuclear industry these studies are indispensable due to economic, environmental and social impacts that could result in an accident during the operation of a nuclear reactor. In this paper the preparation, simulation and analysis of results of a turbine shot transient, which is not taken into operation the bypass is presented. The study is realized for a BWR of 2027 MWt, to an intermediate cycle life and using the computer code Simulate-3K a depressurization stage of the vessel is created which shows the response of other security systems and gives a coherent prediction to the event presented type. (Author)

  19. Stress analysis method for clearance-fit joints with bearing-bypass loads

    Science.gov (United States)

    Naik, R. A.; Crews, J. H., Jr.

    1989-01-01

    Within a multi-fastener joint, fastener holes may be subjected to the combined effects of bearing loads and loads that bypass the hole to be reacted elsewhere in the joint. The analysis of a joint subjected to search combined bearing and bypass loads is complicated by the usual clearance between the hole and the fastener. A simple analysis method for such clearance-fit joints subjected to bearing-bypass loading has been developed in the present study. It uses an inverse formulation with a linear elastic finite-element analysis. Conditions along the bolt-hole contact arc are specified by displacement constraint equations. The present method is simple to apply and can be implemented with most general purpose finite-element programs since it does not use complicated iterative-incremental procedures. The method was used to study the effects of bearing-bypass loading on bolt-hole contact angles and local stresses. In this study, a rigid, frictionless bolt was used with a plate having the properties of a quasi-isotropic graphite/epoxy laminate. Results showed that the contact angle as well as the peak stresses around the hole and their locations were strongly influenced by the ratio of bearing and bypass loads. For single contact, tension and compression bearing-bypass loading had opposite effects on the contact angle. For some compressive bearing-bypass loads, the hole tended to close on the fastener leading to dual contact. It was shown that dual contact reduces the stress concentration at the fastener and would, therefore, increase joint strength in compression. The results illustrate the general importance of accounting for bolt-hole clearance and contact to accurately compute local bolt-hole stresses for combined bearings and bypass loading.

  20. Numerical simulation of an alternative to prevent hydrates formation in a bypass section

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Lucilla Coelho; Oliveira Junior, Joao Americo Aguirre; Fonte, Clarissa Bergman [Engineering Simulation and Scientific Software Ltda. (ESSS), Florianopolis, SC (Brazil); Silva, Fabricio Soares da; Moraes, Carlos Alberto Capela [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    This work presents the use of Computational Fluid Dynamics to evaluate the feasibility of MEG (monoethylene glycol) injection as an alternative to prevent hydrate formation in a bypass section, present in an inlet module of a separation device of a subsea separation system. As the bypass section is open to the main pipeline, MEG will probably be dragged due to secondary flows generated by the main flow stream. The MEG removal rate is estimated, as well as the internal heat transfer between the currents and the heat loss to the external environment in order to estimate the temperature in the equipment. In a first step, the MEG removal was evaluated considering the heat transfer between the liquid phase (composed of water, oil and MEG) and the gas phase as well as the heat transfer by forced convection to the external environment. In a second step, the influence of a thermal insulation layer around the bypass line, reducing the heat loss to the external environment, was studied. Both simulations (with or without thermal insulation) showed the establishment of secondary flows in the open connection between the main line and bypass line, promoting the removal of MEG from the bypass section and enabling other components of the liquid phase and/or gas to enter in the bypass line. This MEG removal is faster when thermal isolation was considered, due to the fact that higher temperatures are established in the bypass, maintaining the liquid phase with lower densities and viscosities. With regard to temperature, the insulation was able to keep higher temperatures at the bypass line than those obtained without insulation, indicating that the combination of MEG injection and thermal insulation may be able to avoid the critical condition for hydrate formation. (author)

  1. Secondary coolant purification system with demineralizer bypass

    International Nuclear Information System (INIS)

    Apparatus and method are provided for a nuclear stream supply system for adequately controlling the chemistry of the secondary coolant. The invention includes means for the addition of volatile chemicals, a full flow condensate demineralizer, continuous blowdown capability, radiation detection means, a condensate demineralizer bypass line, and an auxiliary demineralizer bypass line, and an auxiliary demineralizer sized to handle full blowdown flow. The auxiliary demineralizer is cut into the system and the steam generator feedwater flow is bypassed around the full flow condensate demineralizer whenever radioactivity is detected in the secondary coolant

  2. Your diet after gastric bypass surgery

    Science.gov (United States)

    ... low-fat or nonfat hard cheeses, cottage cheese, milk, and yogurt. After gastric bypass surgery, your body will not absorb some important vitamins and minerals. You will need to take these vitamins and ...

  3. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... perfect bypass. We are often asked how you learn this. Important question. Hours and hours of suturing ... OR-Live” makes it easy for you to learn more. Just click on the “Request information” button ...

  4. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... Artery Bypass June 10, 2009 Welcome to the University of Maryland Medical Center in Baltimore, where you ... to Maryland. Welcome to Baltimore. Welcome to the University of Maryland Medical Center here in OR-26. ...

  5. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... on for coronary surgery. A very durable bypass running here and supplying the chest wall with blood. ... case the branch, the typical branch that is running between the two heart chambers is located more ...

  6. Types of Coronary Artery Bypass Grafting

    Science.gov (United States)

    ... best option for you based on your needs. Traditional Coronary Artery Bypass Grafting Traditional CABG is used when at least one major ... Grafting This type of CABG is similar to traditional CABG because the chest bone is opened to ...

  7. Exhaust gas bypass valve control for thermoelectric generator

    Science.gov (United States)

    Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter Jacobus; Anderson, Todd Alan

    2012-09-04

    A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

  8. Phrenic Nerve Injury during Coronary Artery Bypass

    OpenAIRE

    Guinn, Gene A.; Beall, Arthur C.; Lamki, Neela; Heibig, Jacques; Thornby, John

    1990-01-01

    After coronary artery bypass, some patients have diaphragmatic elevation, usually on the left side. To test our hypothesis that this phenomenon is due to phrenic nerve injury resulting from either 1) dissection of the proximal portion of the left internal mammary artery or 2) topical cooling of the heart with icy slush, we performed the following 2-part study. First, we reviewed our hospital records of 99 coronary artery bypass patients, 55 of whom had received left internal mammary artery gr...

  9. An experimental study of nerve bypass graft

    Institute of Scientific and Technical Information of China (English)

    XU Jie; LI Xue-shi

    2008-01-01

    Objective: To study the use of a nerve "bypass" graft as a possible alternative to neurolysis or segmental resection with interposition grafting in the treatment of neuroma-in-continuity. Methods: A sciatic nerve crush injury model was established in the Sprague-Dawley rat by compression with a straight hemostatic forceps. Epineurial windows were created proximal and distal to the injury site. An 8-mm segment of radial nerve was harvested and coaptated to the sciatic nerve at the epineurial window sites proximal and distal to the compressed segment (bypass group). A sciatic nerve crush injury without bypass served as a control. Nerve conduction studies were performed over an 8-week period. Sciatic nerves were then harvested and studied under transmission electron microscopy. Myelinated axon counts were obtained. Results: Nerve conduction velocity was significantly faster in the bypass group than in the control group at 8 weeks (63.57 m/s±5.83 m/s vs. 54.88 m/s±4.79m/s, P<0.01). Myelinated axon counts in distal segments were found more in the experimental sciatic nerve than in the control sciatic nerve. Significant axonal growth was noted in the bypass nerve segment itself. Conclusion: Nerve bypass may serve to augment peripheral axonal growth while avoiding further loss of the native nerve.

  10. Early results of coronary artery bypass grafting with coronary endarterectomy for severe coronary artery disease

    Directory of Open Access Journals (Sweden)

    Toischer Karl

    2009-09-01

    Full Text Available Abstract Background Despite the existence of controversial debates on the efficiency of coronary endarterectomy (CE, it is still used as an adjunct to coronary artery bypass grafting (CABG. This is particularly true in patients with endstage coronary artery disease. Given the improvements in cardiac surgery and postoperative care, as well as the rising number of elderly patient with numerous co-morbidities, re-evaluating the pros and cons of this technique is needed. Methods Patient demographic information, operative details and outcome data of 104 patients with diffuse calcified coronary artery disease were retrospectively analyzed with respect to functional capacity (NYHA, angina pectoris (CCS and mortality. Actuarial survival was reported using a Kaplan-Meyer analysis. Results Between August 2001 and March 2005, 104 patients underwent coronary artery bypass grafting (CABG with adjunctive coronary endarterectomy (CE in the Department of Thoracic-, Cardiac- and Vascular Surgery, University of Goettingen. Four patients were lost during follow-up. Data were gained from 88 male and 12 female patients; mean age was 65.5 ± 9 years. A total of 396 vessels were bypassed (4 ± 0.9 vessels per patient. In 98% left internal thoracic artery (LITA was used as arterial bypass graft and a total of 114 vessels were endarterectomized. CE was performed on right coronary artery (RCA (n = 55, on left anterior descending artery (LAD (n = 52 and circumflex artery (RCX (n = 7. Ninety-five patients suffered from 3-vessel-disease, 3 from 2-vessel- and 2 from 1-vessel-disease. Closed technique was used in 18%, open technique in 79% and in 3% a combination of both. The most frequent endarterectomized localization was right coronary artery (RCA = 55%. Despite the severity of endstage atherosclerosis, hospital mortality was only 5% (n = 5. During follow-up (24.5 ± 13.4 months, which is 96% complete (4 patients were lost caused by unknown address 8 patients died (cardiac

  11. Influence of mis-match of weld and base material creep properties on elevated temperature design of pressure vessels and piping

    International Nuclear Information System (INIS)

    The stress and strain concentrations developed at the weldments during the long time operation of pressure vessels and piping at high temperature due to the mis-match in the creep properties of weldment constituents (weld, heat affected zone and base metal) are estimated using detailed finite element analysis. Three materials, viz. 2.25Cr 1Mo, SS 316 LN and modified 9Cr 1 Mo which are the most commonly used materials in the nuclear and thermal power plants are considered. A longitudinal seam weld with single and double V (X) configurations are analysed. Parametric studies have been done on weld angle and stresses. Based on the analysis, critical locations and the maximum stress concentration factors in the weldments for the above materials are identified. The weld design procedures of the currently used pressure vessel and piping codes are commented. The importance of ductility based failure criteria is emphasised. (orig.)

  12. Vibration model of a pressurized water reactor which takes into account the fluid influence in the annular gap between core barrel and pressure vessel

    International Nuclear Information System (INIS)

    A theoretical vibration model of a pressurized water reactor is established and studied which takes into account the fluid-structure interaction of the coupled three-dimensional system reactor pressure vessel-core barrel (reactor cavity). Vibration differential equations are derived only for the two-dimensional movement; the eigenfrequencies and amplitude ratios of the undamped system as well as a dimensionless damping factor of cavity vibrations are calculated with the data of the WWER-440, and discussed. (orig.)

  13. STCW公约对救助船员培训的影响与应用%The influence and application of the STCW convention to seafarers on board rescue vessels

    Institute of Scientific and Technical Information of China (English)

    李新华

    2013-01-01

    This paper gave a general introduction of the background and the main points of the Manila amendments to the STCW convention, and analyzed the influence and application for the training of seafarers on board rescue vessels.%  文中介绍了STCW公约马尼拉修正案产生的背景及修正内容,提出了履行公约对救助船员培训的相关影响及应用。

  14. PWR pressure vessel integrity during overcooling accidents

    International Nuclear Information System (INIS)

    Pressurized water reactors are susceptible to certain types of hypothetical accidents that under some circumstances, including operation of the reactor beyond a critical time in its life, could result in failure of the pressure vessel as a result of propagation of crack-like defects in the vessel wall. The accidents of concern are those that result in thermal shock to the vessel while the vessel is subjected to internal pressure. Such accidents, referred to as pressurized thermal shock or overcooling accidents (OCA), include a steamline break, small-break LOCA, turbine trip followed by stuck-open bypass valves, the 1978 Rancho Seco and the TMI accidents and many other postulated and actual accidents. The source of cold water for the thermal shock is either emergency core coolant or the normal primary-system coolant. ORNL performed fracture-mechanics calculations for a steamline break in 1978 and for a turbine-trip case in 1980 and concluded on the basis of the results that many more such calculations would be required. To meet the expected demand in a realistic way a computer code, OCA-I, was developed that accepts primary-system temperature and pressure transients as input and then performs one-dimensional thermal and stress analyses for the wall and a corresponding fracture-mechanics analysis for a long axial flaw. The code is briefly described, and its use in both generic and specific plant analyses is discussed

  15. Brain microvascular function during cardiopulmonary bypass

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, H.R.; Husum, B.; Waaben, J.; Andersen, K.; Andersen, L.I.; Gefke, K.; Kaarsen, A.L.; Gjedde, A.

    1987-11-01

    Emboli in the brain microvasculature may inhibit brain activity during cardiopulmonary bypass. Such hypothetical blockade, if confirmed, may be responsible for the reduction of cerebral metabolic rate for glucose observed in animals subjected to cardiopulmonary bypass. In previous studies of cerebral blood flow during bypass, brain microcirculation was not evaluated. In the present study in animals (pigs), reduction of the number of perfused capillaries was estimated by measurements of the capillary diffusion capacity for hydrophilic tracers of low permeability. Capillary diffusion capacity, cerebral blood flow, and cerebral metabolic rate for glucose were measured simultaneously by the integral method, different tracers being used with different circulation times. In eight animals subjected to normothermic cardiopulmonary bypass, and seven subjected to hypothermic bypass, cerebral blood flow, cerebral metabolic rate for glucose, and capillary diffusion capacity decreased significantly: cerebral blood flow from 63 to 43 ml/100 gm/min in normothermia and to 34 ml/100 gm/min in hypothermia and cerebral metabolic rate for glucose from 43.0 to 23.0 mumol/100 gm/min in normothermia and to 14.1 mumol/100 gm/min in hypothermia. The capillary diffusion capacity declined markedly from 0.15 to 0.03 ml/100 gm/min in normothermia but only to 0.08 ml/100 gm/min in hypothermia. We conclude that the decrease of cerebral metabolic rate for glucose during normothermic cardiopulmonary bypass is caused by interruption of blood flow through a part of the capillary bed, possibly by microemboli, and that cerebral blood flow is an inadequate indicator of capillary blood flow. Further studies must clarify why normal microvascular function appears to be preserved during hypothermic cardiopulmonary bypass.

  16. "Orpheus" cardiopulmonary bypass simulation system.

    Science.gov (United States)

    Morris, Richard W; Pybus, David A

    2007-12-01

    In this paper we describe a high-fidelity perfusion simulation system intended for use in the training and continuing education of perfusionists. The system comprises a hydraulic simulator, an electronic interface unit and a controlling computer with associated real-time computer models. It is designed for use within an actual operating theatre, or within a specialized simulation facility. The hydraulic simulator can be positioned on an operating table and physically connected to the circuit of the institutional heart-lung machine. The institutional monitoring system is used to display the arterial and central venous pressures, the ECG and the nasopharyngeal temperature using appropriate connections. The simulator is able to reproduce the full spectrum of normal and abnormal events that may present during the course of cardiopulmonary bypass. The system incorporates a sophisticated blood gas model that accurately predicts the behavior of a modern, hollow-fiber oxygenator. Output from this model is displayed in the manner of an in-line blood gas electrode and is updated every 500 msecs. The perfusionist is able to administer a wide variety of drugs during a simulation session including: vasoconstrictors (metaraminol, epinephrine and phenylephrine), a vasodilator (sodium nitroprusside), chronotropes (epinephrine and atropine), an inotrope (epinephrine) and modifiers of coagulation (heparin and protamine). Each drug has a pharmacokinetic profile based on a three-compartment model plus an effect compartment. The simulation system has potential roles in the skill training of perfusionists, the development of crisis management protocols, the certification and accreditation of perfusionists and the evaluation of new perfusion equipment and/or techniques. PMID:18293807

  17. Measurement of canine pancreatic perfusion using dynamic computed tomography: Influence of input-output vessels on deconvolution and maximum slope methods

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Miori, E-mail: miori@mx6.et.tiki.ne.jp [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Tsuji, Yoshihisa, E-mail: y.tsuji@extra.ocn.ne.jp [Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Shogoinkawara-cho 54, Sakyo-ku 606-8507 (Japan); Katabami, Nana; Shimizu, Junichiro; Lee, Ki-Ja [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Iwasaki, Toshiroh [Department of Veterinary Internal Medicine, Tokyo University of Agriculture and Technology, Saiwai-cho, 3-5-8, Fuchu 183-8509 (Japan); Miyake, Yoh-Ichi [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Yazumi, Shujiro [Digestive Disease Center, Kitano Hospital, 2-4-20 Ougi-machi, Kita-ku, Osaka 530-8480 (Japan); Chiba, Tsutomu [Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Shogoinkawara-cho 54, Sakyo-ku 606-8507 (Japan); Yamada, Kazutaka, E-mail: kyamada@obihiro.ac.jp [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan)

    2011-01-15

    Objective: We investigated whether the prerequisite of the maximum slope and deconvolution methods are satisfied in pancreatic perfusion CT and whether the measured parameters between these algorithms are correlated. Methods: We examined nine beagles injected with iohexol (200 mgI kg{sup -1}) at 5.0 ml s{sup -1}. The abdominal aorta and splenic and celiac arteries were selected as the input arteries and the splenic vein, the output veins. For the maximum slope method, we determined the arterial contrast volume of each artery by measuring the area under the curve (AUC) and compared the peak enhancement time in the pancreas with the contrast appearance time in the splenic vein. For the deconvolution method, the artery-to-vein collection rate of contrast medium was calculated. We calculated the pancreatic tissue blood flow (TBF), tissue blood volume (TBV), and mean transit time (MTT) using both algorithms and investigated their correlation based on vessel selection. Results: The artery AUC significantly decreased as it neared the pancreas (P < 0.01). In all cases, the peak time of the pancreas (11.5 {+-} 1.6) was shorter than the appearance time (14.1 {+-} 1.6) in the splenic vein. The splenic artery-vein combination exhibited the highest collection rate (91.1%) and was the only combination that was significantly correlated between TBF, TBV, and MTT in both algorithms. Conclusion: Selection of a vessel nearest to the pancreas is considered as a more appropriate prerequisite. Therefore, vessel selection is important in comparison of the semi-quantitative parameters obtained by different algorithms.

  18. Measurement of canine pancreatic perfusion using dynamic computed tomography: Influence of input-output vessels on deconvolution and maximum slope methods

    International Nuclear Information System (INIS)

    Objective: We investigated whether the prerequisite of the maximum slope and deconvolution methods are satisfied in pancreatic perfusion CT and whether the measured parameters between these algorithms are correlated. Methods: We examined nine beagles injected with iohexol (200 mgI kg-1) at 5.0 ml s-1. The abdominal aorta and splenic and celiac arteries were selected as the input arteries and the splenic vein, the output veins. For the maximum slope method, we determined the arterial contrast volume of each artery by measuring the area under the curve (AUC) and compared the peak enhancement time in the pancreas with the contrast appearance time in the splenic vein. For the deconvolution method, the artery-to-vein collection rate of contrast medium was calculated. We calculated the pancreatic tissue blood flow (TBF), tissue blood volume (TBV), and mean transit time (MTT) using both algorithms and investigated their correlation based on vessel selection. Results: The artery AUC significantly decreased as it neared the pancreas (P < 0.01). In all cases, the peak time of the pancreas (11.5 ± 1.6) was shorter than the appearance time (14.1 ± 1.6) in the splenic vein. The splenic artery-vein combination exhibited the highest collection rate (91.1%) and was the only combination that was significantly correlated between TBF, TBV, and MTT in both algorithms. Conclusion: Selection of a vessel nearest to the pancreas is considered as a more appropriate prerequisite. Therefore, vessel selection is important in comparison of the semi-quantitative parameters obtained by different algorithms.

  19. Vessel Arrival Info - Legacy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Arrival Info is a spreadsheet that gets filled out during the initial stage of the debriefing process by the debriefer. It contains vessel name, trip...

  20. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  1. Guam Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Guam. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  2. Florida Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Florida. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  3. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  4. Effect of the yaw injection angle on the ECC bypass in comparison with the horizontal DVI

    International Nuclear Information System (INIS)

    The comparison tests for the direct emergency core cooling (ECC) bypass fraction were experimentally performed with a typical direct vessel injection (DVI) nozzle and an ECC column nozzle having a yaw injection angle to the gravity axis. The ECC yaw injection nozzle is newly introduced to make an ECC water column in the downcomer region. The yaw injection angle of the ECC water relative to the gravity axis is varied from 0 to (±)90 deg. stepped by 45 deg. . The tests are performed in the air-water separate effect test facility (direct injection visualization and analysis (DIVA)), which is a 1/7.07 linearly scaled-down model of the APR1400 nuclear reactor. The test results show that (1) if the ECC water column is injected into the wake region which is induced by the hot leg blunt body in the downcomer annulus, the ECC bypass fraction is greatly reduced compared with the typical horizontal ECC injection which makes ECC film on the downcomer wall. At the same time, the ECC penetration toward the lower downcomer region becomes larger than those of a typical horizontal type of direct vessel injection on the downcomer wall vertically. (2) If the ECC water column is injected near the broken cold leg, the ECC water is directly bypassed. Thus, the ECC penetration fraction is greatly reduced compared with a typical film type of the horizontal ECC injection. (3) In order to minimize the ECC bypass fraction, the ECC water should be injected toward the wake region of the hot leg blunt bodies

  5. Non-invasive assessment of coronary artery bypass grafts - an update; Koronare Bypassdiagnostik mit CT und MRT - eine Bestandsaufnahme

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F.; Ehrhard, K.; Kunz, R.P.; Oberholzer, K.; Mildenberger, P.; Thelen, M. [Klinik und Poliklinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Abegunewardene, N.; Horstick, G. [2. Medizinische Klinik und Poliklinik der Johannes Gutenberg-Univ. Mainz (Germany); Hake, U. [Klinik und Poliklinik fuer Herz-Thorax- und Gefaesschirurgie der Johannes Gutenberg-Univ. Mainz (Germany)

    2004-08-01

    The limited lifetime and the correlation between graft occlusion and recurring symptoms underline the need for repeated imaging of coronary artery bypass grafts. CT and MRI allow for noninvasive imaging of coronary bypasses with high accuracies concerning the patency of these vessels. Multidetector CT seem to be the CT technique of choice, especially after the introduction of 16 slice CT scanners for morphologic assessment of coronary artery bypass grafts. Compared with MRI, CT is a robust technique for assessment of cardiac anastomoses, native coronary arteries, anf for the detection of graft stenoses. MRI, however, is able to deliver functional information about the grafts and the recipient coronary arteries by determining the coronary flow reserve. Furthermore, it can be integrated in a multiparametric MR examination protocol. The follow-up of asymptomatic patients can primarily be done by these non-invasive techniques as nearly every third patient reveals an asymptomatic bypass occlusion 5 years after operation. Furthermore, patients with atypical complaints after the operation may undergo non-invasive imaging as long as documented patency of the bypass averts coronary angiography. Patients with recurrent angina pectoris and/or myocardial ischemia discovered by other cardiologic tests have to undergo coronary angiography. (orig.)

  6. In-vessel core debris retention through external flooding of the reactor pressure vessel. State-of-the-art report

    International Nuclear Information System (INIS)

    An overview of the state-of-the-art knowledge on the ex-vessel flooding accident management strategy for severe accidents in a NPP has been given. The feasibility has been discussed, as well as the in- and ex-vessel phenomena, which influence the structural integrity of the vessel. Finally, some computer codes with the ability to model the phenomena involved in ex-vessel flooding have been discussed. (orig./HP)

  7. Dynamic Cerebral Autoregulation after Cardiopulmonary Bypass

    DEFF Research Database (Denmark)

    Christiansen, Claus Behrend; Berg, Ronan M G; Plovsing, Ronni;

    2016-01-01

    Background Cerebral hemodynamic disturbances in the peri- or postoperative period may contribute to postoperative cognitive dysfunction (POCD) in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). We therefore examined dynamic cerebral autoregulation (d......CA) post-CPB and changes in neurocognitive function in patients that had undergone CABG. Materials and Methods We assessed dCA by transfer function analysis of spontaneous oscillations between arterial blood pressure and middle cerebral artery blood flow velocity measured by transcranial Doppler ultrasound...

  8. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Science.gov (United States)

    ROBOT-ASSISTED MINIMALLY INVASIVE CORONARY ARTERY BYPASS SURGERY OPERATION PINNACLEHEALTH HARRISBURG HOSPITAL HARRISBURG, PA 00:00:08 ... Hospital campus. We are going to witness a robot-assisted minimally invasive coronary artery bypass surgery operation. ...

  9. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ROBOT-ASSISTED MINIMALLY INVASIVE CORONARY ARTERY BYPASS SURGERY OPERATION PINNACLEHEALTH HARRISBURG HOSPITAL HARRISBURG, PA 00:00:08 ... Hospital campus. We are going to witness a robot-assisted minimally invasive coronary artery bypass surgery operation. ...

  10. 21 CFR 870.4350 - Cardiopulmonary bypass oxygenator.

    Science.gov (United States)

    2010-04-01

    ... bypass oxygenator. (a) Identification. A cardiopulmonary bypass oxygenator is a device used to exchange gases between blood and a gaseous environment to satisfy the gas exchange needs of a patient during...

  11. Coronary Artery Bypass Graft Surgery (Beyond the Basics)

    Science.gov (United States)

    ... for people with coronary heart disease is called "percutaneous coronary intervention" (PCI), or "stenting." This involves using a flexible ... artery disease: Coronary artery bypass graft surgery versus percutaneous coronary intervention Coronary artery bypass grafting in patients with cerebrovascular ...

  12. Influence of long-term thermal aging on the microstructural evolution of nuclear reactor pressure vessel materials: An atom probe study

    International Nuclear Information System (INIS)

    Atom probe field ion microscopy (APFIM) investigations of the microstructure of unaged (as-fabricated) and long-term thermally aged (∼ 100,000 h at 280 C) surveillance materials from commercial reactor pressure vessel steels were performed. This combination of materials and conditions permitted the investigation of potential thermal-aging effects. This microstructural study focused on the quantification of the compositions of the matrix and carbides. The APFIM results indicate that there was no significant microstructural evolution after a long-term thermal exposure in weld, plate, or forging materials. The matrix depletion of copper that was observed in weld materials was consistent with the copper concentration in the matrix after the stress-relief heat treatment. The compositions of cementite carbides aged for 100,000 h were compared with the Thermocalc trademark prediction. The APFIM comparisons of materials under these conditions are consistent with the measured change in mechanical properties such as the Charpy transition temperature

  13. Dacron or PTFE for above-knee femoropopliteal bypass

    DEFF Research Database (Denmark)

    Jensen, Leif P.; Lepäntalo, M.; Fossdal, J.E.;

    2007-01-01

    analysis. Age, gender, indication (claudication: 65%), run-off (2 or 3 vessels: 76%), diabetes (17%) and hypertension (31%) as well as cerebrovascular (9%) and cardiac (33%) risks were evenly distributed. Patients were followed postoperatively at 1, 12 and 24 months. Patency assessment was based on ankle......-brachial pressures or imaging in case of doubt. RESULTS: The two-year primary patency rates for Dacron and PTFE were 70% and 57% (p=0.02), whereas the secondary patency rates were 76% and 65% (p=0.04), respectively. Primary patency at two years was significantly influenced by the number of patent crural vessels (two...

  14. Investigation on the Core Bypass Flow in a Very High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin

    2013-10-22

    Uncertainties associated with the core bypass flow are some of the key issues that directly influence the coolant mass flow distribution and magnitude, and thus the operational core temperature profiles, in the very high-temperature reactor (VHTR). Designers will attempt to configure the core geometry so the core cooling flow rate magnitude and distribution conform to the design values. The objective of this project is to study the bypass flow both experimentally and computationally. Researchers will develop experimental data using state-of-the-art particle image velocimetry in a small test facility. The team will attempt to obtain full field temperature distribution using racks of thermocouples. The experimental data are intended to benchmark computational fluid dynamics (CFD) codes by providing detailed information. These experimental data are urgently needed for validation of the CFD codes. The following are the project tasks: • Construct a small-scale bench-top experiment to resemble the bypass flow between the graphite blocks, varying parameters to address their impact on bypass flow. Wall roughness of the graphite block walls, spacing between the blocks, and temperature of the blocks are some of the parameters to be tested. • Perform CFD to evaluate pre- and post-test calculations and turbulence models, including sensitivity studies to achieve high accuracy. • Develop the state-of-the art large eddy simulation (LES) using appropriate subgrid modeling. • Develop models to be used in systems thermal hydraulics codes to account and estimate the bypass flows. These computer programs include, among others, RELAP3D, MELCOR, GAMMA, and GAS-NET. Actual core bypass flow rate may vary considerably from the design value. Although the uncertainty of the bypass flow rate is not known, some sources have stated that the bypass flow rates in the Fort St. Vrain reactor were between 8 and 25 percent of the total reactor mass flow rate. If bypass flow rates are on the

  15. Obstructive and enteropathic syndromes after jejunoileal bypass surgery

    International Nuclear Information System (INIS)

    Small bowel bypass procedures for morbid obesity have been associated with many postoperative complications. With the use of the Scott procedure, the bypassed or excluded small bowel segment has recently been the focus of 2 syndromes - 'bypass enteritis' and 'defunctioned bowel syndrome'. We describe these postoperative complications and present their significant radiologic features. (orig.)

  16. Obstructive and enteropathic syndromes after jejunoileal bypass surgery

    Energy Technology Data Exchange (ETDEWEB)

    Karasick, D.; Karasick, S.

    1981-05-15

    Small bowel bypass procedures for morbid obesity have been associated with many postoperative complications. With the use of the Scott procedure, the bypassed or excluded small bowel segment has recently been the focus of 2 syndromes - 'bypass enteritis' and 'defunctioned bowel syndrome'. We describe these postoperative complications and present their significant radiologic features.

  17. Outcomes after off-pump coronary bypass surgery

    NARCIS (Netherlands)

    Dijk, Diederik van

    2002-01-01

    The complications associated with in coronary artery bypass surgery (CABG) using cardiopulmonary bypass (CPB) have led to a renewed interest in coronary bypass surgery on the beating heart. The primary objective of the Octopus Study was to compare cognitive outcome between patients randomized to off

  18. 21 CFR 870.4390 - Cardiopulmonary bypass pump tubing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass pump tubing. 870.4390... bypass pump tubing. (a) Identification. A cardiopulmonary bypass pump tubing is polymeric tubing which is used in the blood pump head and which is cyclically compressed by the pump to cause the blood to...

  19. 21 CFR 870.4240 - Cardiopulmonary bypass heat exchanger.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass heat exchanger. 870.4240... bypass heat exchanger. (a) Identification. A cardiopulmonary bypass heat exchanger is a device, consisting of a heat exchange system used in extracorporeal circulation to warm or cool the blood...

  20. 21 CFR 870.4250 - Cardiopulmonary bypass temperature controller.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass temperature controller. 870... Cardiopulmonary bypass temperature controller. (a) Identification. A cardiopulmonary bypass temperature controller is a device used to control the temperature of the fluid entering and leaving a heat exchanger....

  1. Guillain–Barré Syndrome after Coronary Artery Bypass Graft Surgery:a Case Report

    OpenAIRE

    Manouchehr Hekmat; Hamid Ghaderi; Mahnoosh Foroughi; S. Adeleh Mirjafari

    2016-01-01

    Guillain-Barre syndrome is a neurologic disorder that may appear after infection or major surgery.  Guillian-Barre syndrome following cardiac surgery is rare and only based on case reports, and we review all of the published cases. A 52-year-old man after 5 months suffering from chest pain was referred to our hospital and underwent coronary artery bypass graft for 3 vessel disease. The patient was discharged without complication on the 5th postoperative day. He presented Guillain- Barre syndr...

  2. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... completely endoscopic coronary artery bypass grafting procedure using robotics. We call this operation a “TECAB,” “Totally Endoscopic ... scrub nurse, also a lot of experience with robotics now. And Dr. Atiq Rahman, fellow here for ...

  3. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... bypass graft to the LAD. We have a real long-term option. 4 So again, this is under T guidance. Anesthesia tells me that I am in the descending thoracic aorta. That means I’m on the right track. Once that is done then we sequentially ...

  4. Analysis and testing of electrorheological bypass dampers

    Science.gov (United States)

    Lindler, Jason E.; Wereley, Norman M.

    1998-06-01

    We experimentally validate nonlinear quasi-steady electrorheological (ER) and magnetorheological (MR) damper models, using an idealized Bingham plastic shear flow mechanism, for the flow mode of damper operation. An electrorheological valve or bypass damper was designed, and fabricated using predominantly commercial off-the-shelf hydraulic components. Both the hydraulic cylinder and the bypass duct have cylindrical geometry, and damping forces are developed in the annular bypass via Poiseuille (flow mode) flow. Damper models assume parallel plate geometry. Three nondimensional groups are used for damper analysis, namely, the Bingham number, Bi, the nondimensional plug thickness, (delta) , and the area coefficient defined as the ratio of the piston head area, A(rho ), to the cross-sectional area of the annular bypass, Ad. In the flow mode case, the damping coefficient, which is defined as the ratio of equivalent viscous damping of the Bingham plastic material, Ceq, to the Newtonian viscous damping, C, is a function of the nondimensional plug thickness only. The damper was tested using a mechanical damper dynamometer for sinusoidal stroke of 2 inches, over a range of frequencies below 0.63 Hz. The damping coefficient vs. nondimensional plug thickness diagram was experimentally validated using these data over a range of damper shaft velocities and applied electric field. Because the behaviors of ER and MR fluid are qualitatively similar, these ER damper modeling results may be extended to analysis of flow mode MR dampers.

  5. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... is in place right now. There’s usually some slack or redundancy in the balloon once we initially ... go on bypass, and then it’s without any slack in the right position, and we can inflate ...

  6. Phlegmonous Gastritis Following Coronary Bypass Surgery

    OpenAIRE

    Radhi, J; Kamouna, M; Nyssen, J.

    1999-01-01

    Phlegmonous gastritis is a rare, rapidly progressive and potentially fatal gastric bacterial infection. A case of phlegmonous gastritis following a coronary bypass surgery is described. This condition was not diagnosed premortem due to the nonspecific nature of the gastrointestinal symptoms. Upper gastrointestinal endoscopy may be of value in establishing the diagnosis in emergencies with culture of gastric aspirate and biopsy.

  7. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... coronary artery bypass grafting procedure using robotics. We call this operation a “TECAB,” “Totally Endoscopic Coronary Artery ... see 2 the heart beating behind what we call the “pericardium,” the sack where the heart is ...

  8. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Liew, Gerald; Wang, Jie Jin; Rochtchina, Elena; Wong, Tien Yin; Mitchell, Paul

    2014-01-01

    Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at...

  9. Is a fully heparin-bonded cardiopulmonary bypass circuit superior to a standard cardiopulmonary bypass circuit?

    OpenAIRE

    Mahmood, Sarah; Bilal, Haris; Zaman, Mahvash; Tang, Augustine

    2012-01-01

    A best-evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was ‘Is a fully heparin bonded cardiopulmonary bypass circuit superior to a standard cardiopulmonary bypass circuit?’ Altogether more than 792 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of...

  10. Silver Nitrate and Different Culture Vessels Influence High Frequency Microrhizome Induction In Vitro and Enhancement Growth of Turmeric Plantlet During Ex Vitro Acclimatization

    Directory of Open Access Journals (Sweden)

    Dikash Singh THINGBAIJAM

    2012-11-01

    Full Text Available Eleven cultivars of C. longa var. Lakadong were collected from Manipur having different topography. Curcumin content in different cultivars has been analyzed by using UV-Visible Spectrophotometer (100 Bio-Carry Spectrophotometer. The curcuminoids content were analyzed and quantified for identification of best quality cultivar. Thoubal Cultivar with highest curcumin content (9.44% was subjected for tissue culture technique using different culture vessels and silver nitrate for rapid multiplication and scaling up of microrhizome production. High multiplication rate of 27.40�0.47 were obtained in Murashige and Skoog�s medium supplemented with 3% sucrose + 1 mg L-1 ?-napthalene acetic acid, 4 mg L-1 6-benzyl-amino-purine and 11 ?M silver nitrate. Effect of different culture vessels and silver nitrate were studied for microrhizome and multiple shoots formation. Relatively higher rate of shoots along with microrhizome (17.5�0.32 can be seen in Growtek which was grown without any plant growth regulator. Growtek was used for scaling up of microrhizome production in vitro and utmost microrhizome was produced in liquid Murashige and Skoog�s medium supplemented with 8% sucrose, 1 mg L-1 ?-napthalene acetic acid, 4 mg L-1 6-benzyl-amino-purine and 11 ?M silver nitrate (36.25�0.27. Addition of silver nitrate in the medium resulted in improvement of microrhizome induction in vitro. Higher concentration of silver nitrate (33, 44, 66, 88 ?M negatively affected the microrhizome and shoot multiplication and shows inhibition of tissue response completely. Analysis of in vitro derived plantlets during acclimatization shows that the exogenous applied of silver nitrate shows superior growth as compared to control. 90-95% of plantlets with and 75-80% plantlets without silver nitrate treatment were successfully established under ex vitro acclimatization. The protocol could be utilized for large scale production of true-to-type plantlets and as alternative

  11. Pressure vessel design manual

    CERN Document Server

    Moss, Dennis R

    2013-01-01

    Pressure vessels are closed containers designed to hold gases or liquids at a pressure substantially different from the ambient pressure. They have a variety of applications in industry, including in oil refineries, nuclear reactors, vehicle airbrake reservoirs, and more. The pressure differential with such vessels is dangerous, and due to the risk of accident and fatality around their use, the design, manufacture, operation and inspection of pressure vessels is regulated by engineering authorities and guided by legal codes and standards. Pressure Vessel Design Manual is a solutions-focused guide to the many problems and technical challenges involved in the design of pressure vessels to match stringent standards and codes. It brings together otherwise scattered information and explanations into one easy-to-use resource to minimize research and take readers from problem to solution in the most direct manner possible. * Covers almost all problems that a working pressure vessel designer can expect to face, with ...

  12. Maury Journals - German Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — German vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  13. 抑肽酶对体外循环呼吸指数和胸肺顺应性的影响%The influence of aprotinin on respiratory index and lung-thorax compliance during cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    张兰; 王泉云; 肖红; 廖刃; 刘斌

    2001-01-01

    Objective To study the projection effect of aprotinin on acute lung injury during cardiopulmonary bypass (CPB). Methods Twenty-eight patients scheduled for cardiac value replacement for the first time were randomized into two groups: control group (14 patients) and aprotinin treatment group (14). Pulmonary thoracic compliance (Cs) and dynamic compliance (Cd) were measured at pre-CPB(T1), 10 minutes after aortic crossclamping (T2), and 10 minutes (T3), 60 minutes (T4) after CPB. Arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide(PaCO2), fractional concentration of oxygen in inspired gas (FiO2), and barometric pressure (PB) were measured at the same time. Then respiratory indexes (RI) were calculated. Results There were no differences in the values of Cs,Cd and RI at T1 between the aprotinin group(52.8±13.49, 42.97±9.06, 0.44±0.1) and the control group (56.43±9.29,45.62±6.92,0.45±0.13) respectively(P>0.05).There was a significant (P<0.05) decrease of Cs and Cd at T2 (33.82±8.83, 28.39±6.04), T3(35.42±11.83,30.6±17.88) and T4(37.96±7.27,32.38±6.52) in the control group as compared with basline values (T1)and the values of the aprotinin group (42.74±9.08,36.83±5.47; 43.38±10.88 , 37.27±10.57; 47.64±12.27, 40.52±9.07) respectively. The RI of the control group at T2 (0.78±0.14), T3(0.69±0.12) was higher than either their baseline(T1) or the values of the aprotinin group (0.53±0.14, 0.51±0.1) at the same measure points (P<0.05). Though there was no difference(P>0.05) between T4(0.63±0.13) and their baseline′s in the control group, the values of the control group were higher than those of the aprotinin group at T4(0.49±0.13)(P<0.05). Conclusion Aprotinin has a protection effect on acute lung injury after CPB.%目的探讨抑肽酶是否减轻体外循环(CPB)所致急性肺损伤。方法 28例首次心脏瓣膜置换术患者随机分为对照组及抑肽酶组,各14例。于CPB前(T1

  14. Use of superior thyroid artery as a donor vessel in extracranial-intracranial revascularization procedures: a novel technique.

    Science.gov (United States)

    Mura, Jorge; Cuevas, José Luis; Riquelme, Francisco; Torche, Esteban; Julio, Rodrigo; Isolan, Gustavo Rassier

    2014-12-01

    Objective To describe the use of the superior thyroid artery as a donor vessel in extracranial-intracranial (EC-IC) revascularization when a "low-flow" bypass is required and the superficial temporal artery is not available. Design Case report. Setting University hospital. Participants Four cases. Main Outcome Measures Postoperative course after EC-IC bypass surgery. Results In case 1, the parent vessel was occluded postoperatively. The radial bypass was sufficient to replace the internal carotid artery (ICA) flow, and a prophylactic was turned into a definitive bypass. In case 2, the superior thyroid artery was used because the radial artery was not long enough to reach the external carotid artery. The recipient vessel was modified from the middle cerebral artery to the ophthalmic segment of the ICA. In case 3, the graft was occluded after surgery because of carotid artery reconstruction. In case 4, after surgery/radiotherapy for meningioma, the patient developed wound dehiscence and was reoperated for bypass occlusion. The graft was weak and bled intraoperatively, without infarction. The three first patients are intact, and the fourth remains disabled (Glasgow Outcome Scale: 3; Rankin Scale: 5). Conclusion The superior thyroid artery was adequate for proximal anastomosis in EC-IC procedures in the situations described. PMID:25452901

  15. Influence of ECCS Core Barrel Duct on Reflood Behavior Predicted by MARS Code

    International Nuclear Information System (INIS)

    The present study is to discuss the influence of ECBD on the thermal-hydraulic behavior during the reflood phase of LBLOCA using the MARS-KS code and the related modeling consistent with the one previously developed. Influence of ECBD adopted in APR+ Standard Design on LBLOCA reflood behavior was discussed based on the MARS-KS code prediction. The ECBD was modeled as close as to its physical configuration. The prediction result shows a reduction of ECCS bypass due to ECBD but not significant impact on PCT during reflood phase. Aside from the PCT impact, further code assessment is needed using the applicable experiment simulating a LBLOCA with ECBD to confirm the expected ECBD related phenomena and to get an information of the uncertainty of the phenomena. A device, ECBD (Emergency Core Cooling System Core Barrel Duct), has been proposed at APR+ Standard Design, which was to provide a direct flow path from the elevation of Direct Vessel Injection (DVI) nozzle to the one of active core within the reactor vessel downcomer. It's main function is to reduce the amount of the bypassed ECCS water especially during the reflood phase of large break loss-of-coolant accident (LBLOCA). Since the ECBD design was based on the DVI of APR1400 which was approved through licensing process, the impact of ECBD needs to be assessed in comparison with APR1400 DVI and also the case without ECBD

  16. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner l

  17. Examining blood vessels

    International Nuclear Information System (INIS)

    This patent specification relates to an invention concerned with improvements in or relating to the examination of blood vessels of interest. Particles of dimensions not greater than 8 microns capable of providing detectable signals, are introduced into the blood for examination of a blood vessel. The particles may be sources of radiation, e.g. Ga68. (author)

  18. Magnetic navigation in patients with coronary artery bypass grafting.

    Science.gov (United States)

    Ramcharitar, Steve; van Geuns, Robert-Jan

    2009-05-01

    Magnetic navigation (MN) can precisely control a percutaneous coronary interventions (PCI) guidewire or a device in three-dimensional space within the body without requiring reshaping of the tip to access vessels or areas of the heart that are often challenging using conventional wires. In this article we review and report on the use of magnetic navigation system in secondary revascularisation of coronary arterial bypass grafts (CABG). MN was successfully used in the secondary revascularisation of failed conventional CABG cases. Retrograde PCI through a LIMA is not only feasible but the wires can manage complex stenoses involving a bifurcation by using 3D reconstruction software. Difficult anatomies such as a hairpin bend as highlighted in this paper found at a saphenous vein graft (SVG) anastomosis can be overcome by co-integrating a CTCA 3D dataset for navigation. Preliminary data supports potential advantages in reduction of contrast media usage, crossing and fluoroscopy times and suggest that larger randomised studies are warranted. PMID:19736073

  19. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    This invention relates to an apparatus and method for sealing the cold leg nozzles of a nuclear reactor pressure vessel from a remote location during maintenance and inspection of associated steam generators and pumps while the pressure vessel and refueling canal are filled with water. The apparatus includes a sealing plug for mechanically sealing the cold leg nozzle from the inside of a reactor pressure vessel. The sealing plugs include a primary and a secondary O-ring. An installation tool is suspended within the reactor vessel and carries the sealing plug. The tool telescopes to insert the sealing plug within the cold leg nozzle, and to subsequently remove the plug. Hydraulic means are used to activate the sealing plug, and support means serve to suspend the installation tool within the reactor vessel during installation and removal of the sealing plug

  20. In situ saphenous vein bypass surgery in diabetic patients

    DEFF Research Database (Denmark)

    Jensen, L P; Schroeder, T V; Lorentzen, J E

    1992-01-01

    or foot. Diabetic patients had a significantly lower distal anastomosis than non-diabetic patients (p = 0.0001). The overall 3-year primary and secondary patency rates were 58 and 64%, respectively, with no differences between non-diabetics, non-insulin-dependent diabetics and insulin......From 1986 through to 1990 a total of 483 consecutive in situ infra-inguinal vein bypass procedures were performed in 444 patients, of whom 112 (25%) were diabetics (57 insulin dependent diabetes mellitus and 55 non-insulin-dependent diabetes mellitus). Based on a prospective vascular data registry...... this material was analysed to determine the influence of diabetes on the outcome. Preoperative risk factors were equally distributed among diabetic and non-diabetic patients, except for smoking habits (diabetics: 48%; non-diabetics: 64%, p = 0.002) and cardiac disease (diabetics: 45%; non-diabetics: 29...

  1. Efficiency Biliopancreatic bypass surgery in bulimia nervosa

    OpenAIRE

    Yu I Yashkov; D K Bekuzarov; A V Nikol'skiy

    2008-01-01

    A clinical significance in the treatment of bulimia nervosa patients with morbid obesity had already been raised [10, 13], but we did not find publications on the effectiveness of bariatric surgery in these cases. There is also information about the possibility of applying the operation bilio-pancreatic bypass, effective in patients with morbid obesity with uncontrolled eating behavior for the treatment of patients with anorexia BILIM not suffering from morbid obesity. In this article the dat...

  2. Analgesic Treatment in Laparoscopic Gastric Bypass Surgery

    DEFF Research Database (Denmark)

    Andersen, Lars P H; Werner, Mads U; Rosenberg, Jacob;

    2014-01-01

    This review aimed to present an overview of the randomized controlled trials investigating analgesic regimens used in laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. Literature search was performed in PubMed and EMBASE databases in August 2013 in accordance to PRISMA guidelines. The...... literature search identified nine studies eligible for inclusion. The administration of nonsteroidal anti-inflammatory drugs, local anesthetics (intraperitoneally or subfascially/subcutaneously), transversus abdominis plane block, dexmedetomidine, and ketamine may improve analgesia compared to placebo...

  3. Conduits for Coronary Bypass: Vein Grafts

    OpenAIRE

    Barner, Hendrick B.; Farkas, Emily A.

    2012-01-01

    The saphenous vein has been the principal conduit for coronary bypass grafting from the beginning, circa 1970. This report briefly traces this history and concomitantly presents one surgeons experience and personal views on use of the vein graft. As such it is not exhaustive but meant to be practical with a modest number of references. The focus is that of providing guidance and perspective which may be at variance with that of others and recognizing that there may be many ways to accomplish ...

  4. Conduits for Coronary Bypass: Internal Thoracic Artery

    OpenAIRE

    Barner, Hendrick B.

    2012-01-01

    This second report in the series on coronary artery bypass presents the authors experience and personal views on the internal thoracic artery (ITA) which date to 1966. There has been a very gradual evolution in the acceptance of this conduit which was initially compared with the saphenous vein and viewed as an improbable alternative to it. As is common with concepts and techniques which are 'outside the box' there was skepticism and criticism of this new conduit which was more difficult and t...

  5. Evaluation of MRI coronary bypass graft patency using the volume-rendering method

    International Nuclear Information System (INIS)

    In this study we selected two-dimensional and volume-rendering three-dimensional MR images to evaluate the patency of coronary artery bypass graft (CABG) in comparison with angiography. Twenty-six patients were included in the study (19 men and 7 women, aged 49-85 years, mean age 70.4 years). The total number of bypassed coronary arteries was 62. The MR apparatus used was a Siemens MAGNETOM VISION (1.5 T); the pulse sequence employed was FISP 3D with TR 5 msec, TE 2 msec, FA 15 degrees, and fat saturation. Slice thickness was 4.27 mm, slab thickness 111 mm, and matrix 128 x 256. A body array coil was used, and coronal images were obtained during a 20-second breath-hold and ECG gating. Scanning was initiated 13 seconds after the injection of contrast medium (Gd-DTPA 10 ml+20 ml saline, 3 ml/sec.). Data sets were post-processed to obtain MIP images and volume-rendering 3D images. The MR images were equal to those of angiography in the evaluation of patency of the CABG. Volume rendering had more liberal parameter settings and could be used to observe the vessels under ideal conditions. 3D images enabled observation from multiple angles and were useful in evaluating overlapping vessels. (author)

  6. Myocardial protection with prophylactic oral metoprolol during coronary artery bypass grafting surgery: evaluation by troponin I

    Directory of Open Access Journals (Sweden)

    João Manoel Rossi Neto

    2013-12-01

    Full Text Available INTRODUCTION: Biochemical markers of myocardial injury are frequently altered after cardiac surgery. So far there is no evidence whether oral beta-blockers may reduce myocardial injury after coronary artery bypass grafting. OBJECTIVE: To determine if oral administration of prophylactic metoprolol reduces the release of cardiac troponin I in isolated coronary artery bypass grafting, not complicated by new Q waves. METHODS: A prospective randomized study, including 68 patients, divided in 2 groups: Group A (n=33, control and B (n=35, beta-blockers. In group B, metoprolol tartrate was administered 200 mg/day. The myocardial injury was assessed by troponin I with 1 hour and 12 hours after coronary artery bypass grafting. RESULTS: No significant difference between groups regarding pre-surgical, surgical, complication in intensive care (15% versus 14%, P=0.92 and the total number of hospital events (21% versus 14%, P=0.45 was observed. The median value of troponin I with 12 hours in the study population was 3.3 ng/ml and was lower in group B than in group A (2.5 ng/ml versus 3.7 ng/ml, P<0,05. In the multivariate analysis, the variables that have shown to be independent predictors of troponin I release after 12 hours were: no beta-blockers administration and number of vessels treated. CONCLUSION: The results of this study in uncomplicated coronary artery bypass grafting, comparing the postoperative release of troponin I at 12 hours between the control group and who used oral prophylactic metoprolol for at least 72 hours, allow to conclude that there was less myocardial injury in the betablocker group, giving some degree of myocardial protection.

  7. Brief Analysis of Factors Influencing Installing of Reactor Pressure Vessel Stud on Site%浅析影响反应堆压力容器主螺栓现场安装的因素

    Institute of Scientific and Technical Information of China (English)

    胡大芬; 杨景超; 刘东杰; 陈莲

    2016-01-01

    Based on occurred CPR1000 reactor pressure vessel stud unscrewing in stud hole on site by u-sing multi stud tensioning machine(MSTM)in a domestic nuclear power plant,and combined the charac-teristics of its′stud screw thread structure and performance of MSTM,the influencing factors causing this phenomena were analyzed.The influencing mechanism of each factor was discussed.Then corresponding preventive measures were proposed.%针对国内某核电厂 CPR1000反应堆压力容器主螺栓采用整体螺栓拉伸机现场安装时无法顺利旋入主螺孔的现象,结合其主螺栓螺纹副结构和整体螺栓拉伸机性能特点,分析了造成该现象的影响因素,讨论了各因素的影响机理,并提出了相应的预防措施。

  8. Atypical complications of gastric bypass surgery

    International Nuclear Information System (INIS)

    Although gastric bypass surgery continues to grow in popularity for weight loss and weight maintenance in the morbidly obese, there has been little attention given to the imaging of complications associated with these surgeries. The purpose of our study is to demonstrate the variety of gastric bypass surgery complications that can be identified radiographically, with attention to the more unusual complications. This study was performed with institutional Internal Review Board approval. We performed a 5-year retrospective review of all patients who had undergone gastric bypass surgery, had complications of the surgery, and had studies performed in our department to image these complications. These studies consisted of contrast fluoroscopy and CT. We identified the more common complications of anastomotic stenoses and anastomotic leaks. We also identified six unusual complications as follow: (1) internal herniation through the small bowel mesentery, (2) internal herniation through the transverse mesocolon, (3) external herniation through the abdominal wall incision, (4) enterocutaneous fistulas, (5) antiperistaltic construction of the Roux-en-Y, and (6) incorrect anstomoses of the Roux limbs resulting in a Roux-en-O configuration. Our findings show that a thorough understanding of expected postoperative bowel configuration is essential in the evaluation of these patients. In addition, fluoroscopic evaluation should assess not only anatomy, but also motility

  9. Vein harvesting and techniques for infrainguinal bypass.

    Science.gov (United States)

    Albäck, Anders; Saarinen, Eva; Venermo, Maarit

    2016-04-01

    In order to achieve good long term results after bypass surgery, alongside with good inflow and outflow arteries, the bypass graft material also has an important role. The best patency and limb salvage rates are achieved with autologous vein. If great saphenous vein is not available, acceptable long-term results can be achieved with arm veins and lesser saphenous vein. The quality and size of the vein are important. A small-caliber vein, increased wall thickness, postphlebitic changes and varicosities are associated with a risk of early failure. Preoperative vein mapping with ultrasound reduces readmissions and postoperative surgical site infections. During the mapping, the vein to be used and its main tributaries are marked with a permanent marker pen. To reduce wound complication rates we recommend bridged incisions in vein harvesting. Endoscopic vein harvesting seems to have no benefit compared to open techniques in lower limb bypasses, and has been associated with higher risk of primary patency loss at one year. With deep tunneling of the graft the problems caused by wound infection can be avoided. PMID:26837257

  10. Patient's Perception About Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Kelminda Maria Bulhões Mendonça

    2015-10-01

    Full Text Available ABSTRACT OBJECTIVE: The diagnosis of coronary artery disease referred for heart surgery has an important psychological component. The purpose of this study was to access the difficulties experienced by individuals awaiting coronary artery bypass grafting and to determine strategies that facilitate adaptation to a new lifestyle, modified by the disease. METHODS: A qualitative, exploratory study involving patients admitted to a university teaching hospital in the city of Salvador, Bahia, Brazil, awaiting coronary artery bypass grafting. Semi-structured interviews were performed in accordance with a previously defined script based on the study objective. Each transcription was read in its entirety to verify the representativeness, homogeneity and pertinence of the data obtained (pre-analysis, followed by separation of categories of analysis. RESULTS: The descriptions of this study show that patients admitted to the completion of coronary artery bypass grafting experience a wide range of psychological difficulties, considering that surgery acquires interpretations that vary according to individuals' subjectivity. The patients recognized the benefit of being able to discuss their feelings as a means of diminishing their fear and anxiety. CONCLUSION: Helping patients find resources to confront more positively the daily hospitalization is an important aspect for the health care professionals who assist them. This goal can be achieved through modification of the biomedical model of care for a biopsychosocial view. The investment of time and attention is of fundamental importance and aims to overcome existing deficiencies that interfere with the outcome of patients after cardiac surgery.

  11. Hematological Disorders following Gastric Bypass Surgery: Emerging Concepts of the Interplay between Nutritional Deficiency and Inflammation

    Directory of Open Access Journals (Sweden)

    Mingyi Chen

    2013-01-01

    Full Text Available Obesity and the associated metabolic syndrome are among the most common and detrimental metabolic diseases of the modern era, affecting over 50% of the adult population in the United States. Surgeries designed to promote weight loss, known as bariatric surgery, typically involve a gastric bypass procedure and have shown high success rates for treating morbid obesity. However, following gastric bypass surgery, many patients develop chronic anemia, most commonly due to iron deficiency. Deficiencies of vitamins B1, B12, folate, A, K, D, and E and copper have also been reported after surgery. Copper deficiency can cause hematological abnormalities with or without neurological complications. Despite oral supplementation and normal serum concentrations of iron, copper, folate, and vitamin B12, some patients present with persistent anemia after surgery. The evaluation of hematologic disorders after gastric bypass surgery must take into account issues unique to the postsurgery setting that influence the development of anemia and other cytopenias. In this paper, the clinical characteristics and differential diagnosis of the hematological disorders associated with gastric bypass surgery are reviewed, and the underlying molecular mechanisms are discussed.

  12. Trim optimization of reefer vessels

    OpenAIRE

    Reinius, Leif

    2014-01-01

    The influence of trim on the fuel consumption of reefer ships have been investigated. The project have been carried out at NYKCool AB, a ship operator of reefer vessels.  In the speed range 17-19 knots and deadweight percentage of approximately 70% the smallest calculated resistance is obtained for bow trims which are between -1 m and -2 m depending on the speed.   Stored voyage data from the reefer ships shows that the majority of the voyages are made with positive trims. The data also shows...

  13. Long-term simulations of the dynamics of trout populations on river reaches bypassed by hydroelectric installations analysis of the impact of different hydrological scenarios

    OpenAIRE

    Gouraud, V.; Capra, H.; SABATON C.; Tissot, L.; Lim, P; Vandewalle, F.; Fahrner, G.; Souchon, Y.

    2008-01-01

    Changes in a brown trout (Salmo trutta L.) population result from interaction among various mechanisms which are dependent on environmental conditions and biotic processes. In reaches influenced by the presence of dams, the instream flow in the bypassed section is not the only parameter which affects the population. Flood episodes, the general connectivity of the bypassed section, and the characteristics of the substrate which define the availability and quality of spawning grounds m...

  14. Risk factors for neurological worsening and symptomatic watershed infarction in internal carotid artery aneurysm treated by extracranial-intracranial bypass using radial artery graft.

    Science.gov (United States)

    Matsukawa, Hidetoshi; Tanikawa, Rokuya; Kamiyama, Hiroyasu; Tsuboi, Toshiyuki; Noda, Kosumo; Ota, Nakao; Miyata, Shiro; Oda, Jumpei; Takeda, Rihee; Tokuda, Sadahisa; Kamada, Kyousuke

    2016-08-01

    OBJECT The revascularization technique, including bypass created using the external carotid artery (ECA), radial artery (RA), and M2 portion of middle cerebral artery (MCA), has remained indispensable for treatment of complex aneurysms. To date, it remains unknown whether diameters of the RA, superficial temporal artery (STA), and C2 portion of the internal carotid artery (ICA) and intraoperative MCA blood pressure have influences on the outcome and the symptomatic watershed infarction (WI). The aim of the present study was to evaluate the factors for the symptomatic WI and neurological worsening in patients treated by ECA-RA-M2 bypass for complex ICA aneurysm with therapeutic ICA occlusion. METHODS The authors measured the sizes of vessels (RA, C2, M2, and STA) and intraoperative MCA blood pressure (initial, after ICA occlusion, and after releasing the RA graft bypass) in 37 patients. Symptomatic WI was defined as presence of the following: postoperative new neurological deficits, WI on postoperative diffusion-weighted imaging, and ipsilateral cerebral blood flow reduction on SPECT. Neurological worsening was defined as the increase in 1 or more modified Rankin Scale scores. First, the authors performed receiver operating characteristic curve analysis for continuous variables and the binary end point of the symptomatic WI. The clinical, radiological, and physiological characteristics of patients with and without the symptomatic WI were compared using the log-rank test. Then, the authors compared the variables between patients with and without neurological worsening at discharge and at the 12-month follow-up examination or last hospital visit. RESULTS Symptomatic WI was observed in 2 (5.4%) patients. The mean MCA pressure after releasing the RA graft (< 55 mm Hg; p = 0.017), mean (MCA pressure after releasing the RA graft)/(initial MCA pressure) (< 0.70 mm Hg; p = 0.032), and mean cross-sectional area ratio ([RA/C2 diameter](2) < 0.40 mm [p < 0.0001] and [STA/C2

  15. Dynamic Experimental Study of a Multi—bypass Pulse Tube Refrigerator with Two—bypass Tubes

    Institute of Scientific and Technical Information of China (English)

    YonglinJu; ChaoWang; 等

    1998-01-01

    A dynamic experimental apparatus to measure the instantaneous velocity and pressure in the multibypass pulse tube refrigerator(MPTR) was designed and constructed.Some important experimental results of the instantaneous measurements of the velocity and the pressure in the MPTR with twobypass tubes during actual operation are prsented.The effects of the middle-bypass version on the dynamic pressure and mass flow rate at the cold end of the pulse tube are ev aluated from experimental measurements.DC-flow phenomena are observed in this MPTR.The reasons of the multi-bypass version improved the performance of pulse tube refrigertor are given.

  16. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  17. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  18. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  19. 2011 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  20. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  2. 2011 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  3. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  4. Maury Journals - US Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  5. Coastal Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels that have been issued a Federal permit for the Gulf of Mexico reef fish,...

  6. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. Perfusion Pressure Cerebral Infarct (PPCI) trial - the importance of mean arterial pressure during cardiopulmonary bypass to prevent cerebral complications after cardiac surgery

    DEFF Research Database (Denmark)

    Vedel, Anne G; Holmgaard, Frederik; Rasmussen, Lars Simon;

    2016-01-01

    coronary vessel and/or valve disease and who are undergoing cardiac surgery with the use of cardiopulmonary bypass. Patients are stratified by age and surgical procedure and are randomised 1:1 to either an increased mean arterial pressure (70-80 mmHg) or 'usual practice' (40-50 mmHg) during cardiopulmonary...... caused by emboli, but inadequate blood flow caused by other mechanisms may increase ischaemia in the penumbra or cause watershed infarcts. During cardiopulmonary bypass, blood pressure can be below the lower limit of cerebral autoregulation. Although much debated, the constant blood flow provided by the...... cardiopulmonary bypass system is still considered by many as appropriate to avoid cerebral ischaemia despite the low blood pressure. METHODS/DESIGN: The Perfusion Pressure Cerebral Infarct trial is a single-centre superiority trial with a blinded outcome assessment. The trial is randomising 210 patients with...

  8. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens

    1985-01-01

    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients...... groups. Fractional loss of bicarbonate in urine was higher in controls than in bypass patients. The renal impairment is classified as distal renal tubular acidosis....

  9. Magnetic resonance angiographic assessment after extracranial-intracranial bypass surgery.

    OpenAIRE

    Praharaj, S S; Coulthard, A; Gholkar, A; English, P; Mendelow, A D

    1996-01-01

    Extracranial-intracranial (EC-IC) bypass operation may be performed to augment the distal cerebral circulation. The bypass patency is usually assessed postoperatively with conventional cerebral angiography. Six patients are reported in whom the bypass patency was assessed using magnetic resonance angiography (MRA): Two had intracavernous carotid aneurysms, three had base of skull tumours encompassing the internal carotid artery, and one had occlusion of the right internal carotid artery with ...

  10. Outcomes after off-pump coronary bypass surgery

    OpenAIRE

    van Dijk, Diederik

    2002-01-01

    The complications associated with in coronary artery bypass surgery (CABG) using cardiopulmonary bypass (CPB) have led to a renewed interest in coronary bypass surgery on the beating heart. The primary objective of the Octopus Study was to compare cognitive outcome between patients randomized to off-pump or on-pump CABG. In chapter 2, the literature suggesting that CABG may impair cognitive function is systematically reviewed and chapter 3 describes in detail the rationale and design of the O...

  11. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  12. Attachment Anxiety Predicts Poor Adherence to Dietary Recommendations : an Indirect Effect on Weight Change 1 Year After Gastric Bypass Surgery

    NARCIS (Netherlands)

    Aarts, Floor; Geenen, Rinie; Gerdes, Victor E. A.; van de Laar, Arnold; Brandjes, Dees P. M.; Hinnen, Chris

    2015-01-01

    Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whether attachm

  13. Attachment anxiety predicts poor adherence to dietary recommendations : an indirect effect on weight change 1 year after gastric bypass surgery

    NARCIS (Netherlands)

    Hinnen, C.; Aarts, F.; Geenen, R.

    2014-01-01

    BACKGROUND: Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whe

  14. Attachment anxiety predicts poor adherence to dietary recommendations : an indirect effect on weight change one year after gastric bypass surgery

    NARCIS (Netherlands)

    Aarts, F.; Geenen, R.; Gerdes, V.E.A.; Van de Laar, A., A.; Brandjes, D.P.M.; Hinnen, C.

    2015-01-01

    BACKGROUND: Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whe

  15. Jejunioleal Bypass Procedures in Morbid Obesity: Preoperative Psychological Findings

    Science.gov (United States)

    Webb, Warren W.; And Others

    1976-01-01

    Seventy patients who averaged 155 percent overweight and requested jejunioleal bypass surgery as a treatment intervention for morbid obesity were studied preoperatively for prominent psychological characteristics. (Author)

  16. Hormonal and metabolic responses of fetal lamb during cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    苏肇伉; 周成斌; 张海波; 祝忠群

    2003-01-01

    Objective To study the hormonal and metabolic responses of fetal lamb during cardiopulmonary bypass.Methods Six pregnant ewes underwent fetal cardiopulmonary bypasses with artificial oxygenators and roller pumps for 30 minutes, which maintained the blood gas value at the fetal physiological level. The fetal blood pressure, heart rate, pH value and blood lactate levels were monitored. The levels of catecholamine, cortisol and insulin were measured pre-bypass and then again 30 minutes later. The blood glucose and free fatty acid levels were monitored continuously during the bypass. Fetal hepatic PAS staining was also carried out.Results There were no changes before and during the bypass in fetal blood pressure, heart rate and blood gas. However, pH values decreased and blood lactate levels increased (P<0.05). The fetal catecholamine and cortisol levels increased significantly (P<0.01), while the levels of insulin did not change. The blood glucose and free fatty acid levels increased at the beginning of the bypass (P<0.01), and then gradually slowed down during the bypass. The fetal hepatic PAS staining showed that hepatic glycogen was consumed in large amounts. After 30 minutes of bypass, the fetal lamb would not survive more than 1 hour.Conclusion The fetal lamb has a strong negative reaction to cardiopulmonary bypass.

  17. Cardiac Bypass Pump Flow Management via NIRS Monitoring

    OpenAIRE

    Macnab, Andrew J.; Gagnon, Roy E.; Gagnon, Faith A.; Blackstock, Derek; LeBlanc, Jacques G.

    2003-01-01

    During cardiac surgery, bypass pumps rely on pressure monitors to evaluate flow. We studied whether it would be possible to optimize pump flow by monitoring changes in cerebral cytochrome a,a3 using NIRS to maintain cyt redox status at its pre-bypass level. Method: 18 healthy 7–45 kg swine were placed on bypass for repeated cycles of cooling and re-warming from 36 to 15 to 36°C in 3°C steps. Between each cycle, the swine's bypass pump blood flow rate was adjusted to restore cytochrome redox s...

  18. Obstetrical and neonatal outcomes in women following gastric bypass

    DEFF Research Database (Denmark)

    Berlac, Janne Foss; Skovlund, Charlotte Wessel; Lidegaard, Ojvind

    2014-01-01

    OBJECTIVE: To assess obstetrical and neonatal outcomes in women following gastric bypass, compared with adipose women without surgery and with a normal weight control population. DESIGN: Historical controlled cohort study. SETTING: Denmark. POPULATION: All women undergoing gastric bypass during the...... period 1996-2011, and subsequently giving birth. METHODS AND MAIN OUTCOME MEASURES: Obstetrical and neonatal outcomes in women without gastric bypass matched on age, parity, plurality, year, and body mass index, and normal weight women. RESULTS: In 415 women giving birth after gastric bypass we found...

  19. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... requires just three micro-sized scars, and the patient typically makes a full recovery in just about ... we have done pre-op testing on this patient to make sure his vessels are able for ...

  20. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... go ahead and check if there is adequate pulse on the vessel. I cannot do the same ... is coming in. Okay. It has got suction pulse on it. All right. Very good. Perfect. Okay. ...

  1. TECAB - Totally Endoscopic Coronary Artery Bypass

    Medline Plus

    Full Text Available ... artery. Yes. Okay. And we see some fat calcium plaque here on the vessel. This part is ... ancient Greek, to make an opening between two channels. So I think we are almost ready to ...

  2. Influência da prática da atividade física no resultado da cirurgia de revascularização miocárdica Influence of the practice physical activity in the coronary artery bypass graft surgery results

    Directory of Open Access Journals (Sweden)

    Rosane Maria Nery

    2007-09-01

    Full Text Available OBJETIVO: Avaliar a modificação da freqüência da prática da atividade física no pré e pós-operatório dos pacientes submetidos à cirurgia de revascularização miocárdica (CRM e influência da freqüência da prática da atividade física no pré-operatório no prognóstico dos mesmos. MÉTODO: Estudo de série de casos de 55 pacientes submetidos à CRM, divididos em sedentários e ativos quanto à prática de atividade física. RESULTADOS: Após a realização da CRM, 14 (47% dos pacientes classificados como sedentários no pré-operatório estavam praticando exercícios (p=0,03. Dezessete (59% pacientes sedentários no período pré-operatório apresentaram complicações pós-operatórias em comparação a 8 (31% ativos (p= 0,04. O tempo de internação entre pacientes que não praticavam atividade física e os que praticavam antes da cirurgia foi, respectivamente, 15 (DP= 8 e 12 (DP= 5 dias (p= 0,03. CONCLUSÃO: Esse estudo mostrou a importância da prática de atividade física na fase pré-operatória no resultado da cirurgia de revascularização do miocárdio. Os pacientes fisicamente ativos tiveram tempo de internação hospitalar mais curto e menor número de complicações trans e pósoperatórias no período de um ano. A cirurgia cardíaca promoveu mudança dos hábitos de vida dos pacientes operados, aumentando o número de pacientes fisicamente ativos no seguimento de um ano.OBJECTIVE: To evaluate the modifications of the frequency of physical activities practice of the patients submitted to coronary artery bypass graft surgery (CABG and the influence of the frequency of physical practice activity of the patients before surgery in the surgical prognostic. METHODS: Cases studies of 55 patients submitted to CABG divided in active and sedentary in relation to physical practice activities. RESULTS: After CAGB 14 (47% of the patients classified as sedentary before surgery were practing exercises (p=0.03. Seventeen (59

  3. Study of transient turbine shot without bypass in a BWR; Estudio del transitorio disparo de turbina sin bypass en un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Vallejo Q, J. A.; Martin del Campo M, C.; Fuentes M, L.; Francois L, J. L., E-mail: amhed_jvq@hotmail.com [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-09-15

    The study and analysis of operational transients are important for predicting the behavior of a system to short-terms events and the impact that would cause this transition. For the nuclear industry these studies are indispensable due to economic, environmental and social impacts that could result in an accident during the operation of a nuclear reactor. In this paper the preparation, simulation and analysis of results of a turbine shot transient, which is not taken into operation the bypass is presented. The study is realized for a BWR of 2027 MWt, to an intermediate cycle life and using the computer code Simulate-3K a depressurization stage of the vessel is created which shows the response of other security systems and gives a coherent prediction to the event presented type. (Author)

  4. Awake cardiopulmonary bypass to prevent hemodynamic collapse and loss of airway in a severely symptomatic patient with a mediastinal mass.

    Science.gov (United States)

    Said, Sameh M; Telesz, Brian J; Makdisi, George; Quevedo, Fernando J; Suri, Rakesh M; Allen, Mark S; Mauermann, William J

    2014-10-01

    Management of a large mediastinal mass causing respiratory and hemodynamic compromise represents a major challenge during induction of anesthesia and surgical resection. The hemodynamic changes associated with anesthetic induction and initiation of positive-pressure ventilation can lead to acute hemodynamic collapse or inability to ventilate, or both. Initiation of cardiopulmonary bypass before anesthetic induction represents a safe alternative. We present a 37-year-old woman who underwent successful resection of a large anterior mediastinal mass through sternotomy. Cardiopulmonary bypass was instituted using the right femoral vessels under local analgesia to allow safe anesthetic induction. Her postoperative course was uneventful. This represents an example of a team approach to the management of a complex patient to achieve a successful outcome. PMID:25282247

  5. Hemodynamics Simulation of Stenosed Coronary Bypass Graft

    Institute of Scientific and Technical Information of China (English)

    LIU You-jun; QIAO Aike; DU Jian-jun

    2005-01-01

    By means of FEM, the physiological blood flow in coronary bypass graft is simulated. The stenosis in coronary artery is involved in the graft model,and the deformation of graft end to allow the surgical suture with a smaller diameter coronary is taken into consideration. The flow pattern, secondary flow and wall shear stress in the vicinity of anastomosis are analyzed. It is shown that a zone of low wall stress and high wall stress gradient exists downstream the toe. The floor opposed to the anastomosis is an area of high wall stress and high wall stress gradient. Both the toe downstream and the anastomosis bottom floor are prone to intimal hyperplasia.

  6. Work on the Geneva motorway bypass

    CERN Multimedia

    État de Genève, DCTI, Direction du génie civil

    2006-01-01

    Work on the airport section of the Geneva motorway bypass is continuing and will require the temporary closure of two sliproads allowing traffic to make a U-turn near the airport and the Palexpo exhibition centre. The sliproads on the French and Lausanne sides will be closed until autumn 2006. U-turns will still be possible via clearly marked deviations. For further information: www.autoroute-aeroport.ch We would like to thank you in advance for your understanding. Civil Engineering Department, DCTI, State of Geneva

  7. Impossible Airway Requiring Venovenous Bypass for Tracheostomy

    Directory of Open Access Journals (Sweden)

    Johnathan Gardes

    2012-01-01

    Full Text Available The elective surgical airway is the definitive management for a tracheal stenotic lesion that is not a candidate for tracheal resection, or who has failed multiple-tracheal dilations. This case report details the management of a patient who has failed an elective awake tracheostomy secondary to the inability to be intubated as well as severe scar tissue at the surgical site. A combination of regional anesthesia and venovenous bypass is used to facilitate the surgical airway management of this patient. Cerebral oximetry and a multidisciplinary team approach aid in early detection of an oxygenation issue, as well as the emergent intervention that preserved this patient’s life.

  8. Indications and Outcomes of Prophylactic and Therapeutic Extracranial-to-intracranial Arterial Bypass for Cerebral Revascularization

    Directory of Open Access Journals (Sweden)

    Emre Gazyakan, MD, MSc

    2015-04-01

    Conclusions: The collaboration of neurosurgeons and plastic surgeons in performing EC-IC bypass can result in excellent outcomes with a high bypass patency rate and few complications, particularly for prophylactic EC-IC bypass.

  9. Stellarator helical vacuum vessel

    International Nuclear Information System (INIS)

    A design study of a stainless steel, heavy wall, helically shaped vacuum torus has been made for use in a proposed Stellarator configuration. The study concerns itself with the shape of the vacuum vessel and the division of the vessel into components that can be machined and welded together into a helical configuration. A complication in the design requires that a circular magnet coil be located at the minor toroidal axis and that this coil be embedded within the periphery of the vacuum vessel. The vacuum vessel has a minor toroidal axis diameter of 4 meters, a 68.6-cm shell diameter, and a 1.9-cm wall thickness. It twists about the minor toroidal axis twice in 3600C. (An n value of 2). It is proposed that the unit be made of cylindrical segments with the ends of the cylinders cut at appropriate lengths and angles to form the helix. A mathematical derivation of the dimensions necessary to produce the required shapes of the segments has been made. Also, drawings of the vacuum vessel components have been produced on LANL's CTR CAD/CAM system. The procedure developed can be used for any value of n as dictated by physics requirements

  10. Reactor vessel annealing system

    Science.gov (United States)

    Miller, Phillip E.; Katz, Leonoard R.; Nath, Raymond J.; Blaushild, Ronald M.; Tatch, Michael D.; Kordalski, Frank J.; Wykstra, Donald T.; Kavalkovich, William M.

    1991-01-01

    A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for delivering temperature indicating signals from the temperature monitoring components to the control unit (80-86); and control conductors (8) connectable between the control unit (80-86) and the power supply unit (32-60) for delivering to the power supply unit (32-60) control signals for controlling the level of power supplied by the power supply unit (32-60) to the heater assembly (10).

  11. Acrylic vessel cleaning tests

    International Nuclear Information System (INIS)

    The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory

  12. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Directory of Open Access Journals (Sweden)

    William Ruger Porter

    Full Text Available Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange. Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana was investigated using a differential-contrast, dual-vascular injection (DCDVI technique and high-resolution X-ray microcomputed tomography (μCT. Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory

  13. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Science.gov (United States)

    Porter, William Ruger; Witmer, Lawrence M

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  14. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange

    Science.gov (United States)

    Porter, William Ruger; Witmer, Lawrence M.

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  15. The impact of preoperative trimetazidine use on oxidative parameters in patients undergoing coronary bypass surgery

    Directory of Open Access Journals (Sweden)

    Aydemir Koçarslan

    2013-12-01

    Full Text Available Objective: This prospective, randomised, controlled,clinical study was planned to determine the effect oftrimetazidine on myocardial ischemia-reperfusion duringon pomp coronary artery bypass graft surgery (CABG.Methods: Thirty-five patients undergoing elective CABSin our hospital between 2008 and 2009 were included.The patients were divided into two groups randomly.Seventeen patients consisted trimetazidine group andpreoperative trimetazidine PO received for two weeks,whereas 18 cases were controls. Venous blood sampleswere drawn, preoperatively, intraoperatively and postoperatively,whereas coronary sinus blood samples weredrawn before and after cardiopulmonary bypass. At theend, total oxidative status (TOS and total antioxidant status(TAS were studied and oxidative stress index (OSİwas calculated. Repeated measures analysis of variancewas used to test the influence of operative stress andtrimetazidine use on oxidative parameters.Results: Trimetazidine had no impact on total oxidativestatus, total antioxidant status and oxidative stress index(p>0.05. However, repeated measurements of total oxidativestatus, total antioxidant status and oxidative stressindex have revealed significant impact of operative stresson oxidative parameters (p<0.05.Conclusion: Preoperative trimetazidine use had no impacton total oxidative status, total antioxidant status andoxidative stress index contrary to significant influence ofoperative stress on oxidative parameters.Key words: Coronary bypass surgery, trimetazidine, oxidative stress

  16. 21 CFR 870.4420 - Cardiopulmonary bypass cardiotomy return sucker.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass cardiotomy return sucker. 870.4420 Section 870.4420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Surgical Devices § 870.4420 Cardiopulmonary bypass cardiotomy...

  17. 46 CFR 56.20-20 - Valve bypasses.

    Science.gov (United States)

    2010-10-01

    ... (incorporated by reference; see 46 CFR 56.01-2). (b) Pipe for bypasses should be at least Schedule 80 seamless... 46 Shipping 2 2010-10-01 2010-10-01 false Valve bypasses. 56.20-20 Section 56.20-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND...

  18. Reverse bias protected solar array with integrated bypass battery

    Science.gov (United States)

    Landis, Geoffrey A (Inventor)

    2012-01-01

    A method for protecting the photovoltaic cells in a photovoltaic (PV) array from reverse bias damage by utilizing a rechargeable battery for bypassing current from a shaded photovoltaic cell or group of cells, avoiding the need for a bypass diode. Further, the method mitigates the voltage degradation of a PV array caused by shaded cells.

  19. Dacron or PTFE for above-knee femoropopliteal bypass. a multicenter randomised study

    DEFF Research Database (Denmark)

    Jensen, L P; Lepäntalo, M; Fossdal, J E; Røder, Ole Christian; Jensen, B S; Madsen, M S; Grenager, O; Fasting, H; Myhre, H O; Baekgaard, N; Nielsen, O M; Helgstrand, U; Schroeder, T V

    2007-01-01

    To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass.......To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass....

  20. Reactor pressure vessel materials

    International Nuclear Information System (INIS)

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. Chapter 3 offers a detailed treatment of the selection criteria and properties of reactor pressure vessel materials. The main attention is directed towards steel and ingot making and the subsequent material processing

  1. Hypothermia During Cardiopulmonary Bypass Increases Need for Inotropic Support but Does Not Impact Inflammation in Children Undergoing Surgical Ventricular Septal Defect Closure.

    Science.gov (United States)

    Schmitt, Katharina Rose Luise; Fedarava, Katsiaryna; Justus, Georgia; Redlin, Mathias; Böttcher, Wolfgang; Delmo Walter, Eva Maria; Hetzer, Roland; Berger, Felix; Miera, Oliver

    2016-05-01

    Minimizing the systemic inflammatory response caused by cardiopulmonary bypass is a major concern. It has been suggested that the perfusion temperature affects the inflammatory response. The aim of this prospective study was to compare the effects of moderate hypothermia (32°C) and normothermia (36°C) during cardiopulmonary bypass on markers of the inflammatory response and clinical outcomes (time on ventilator) after surgical closure of ventricular septal defects. During surgical closure of ventricular septal defects under cardiopulmonary bypass, 20 children (median age 4.9 months, range 2.3-38 months; median weight 7.2 kg, range 5.2-11.7 kg) were randomized to a perfusion temperature of either 32°C (Group 1, n = 10) or 36°C (Group 2, n = 10). The clinical data and blood samples were collected before cardiopulmonary bypass, directly after aortic cross-clamp release, and 4 and 24 h after weaning from cardiopulmonary bypass. Time on ventilation as primary outcome did not differ between the two groups. Other clinical outcome parameters like fluid balance or length of stay in the intensive care were also similar in the two groups. Compared with Group 2, Group 1 needed significantly higher and longer inotropic support (P Perfusion temperature did not influence cytokine release, organ injury, or coagulation. Cardiopulmonary bypass temperature does not influence time on ventilation or inflammatory marker release. However, in the present study, with a small patient cohort, patients operated under hypothermic bypass needed higher and longer inotropic support. The use of hypothermic cardiopulmonary bypass in infants and children should be approached with care. PMID:26581834

  2. Application of Computational Physics: Blood Vessel Constrictions and Medical Infuses

    CERN Document Server

    Suprijadi,; Subekti, Petrus; Viridi, Sparisoma

    2013-01-01

    Application of computation in many fields are growing fast in last two decades. Increasing on computation performance helps researchers to understand natural phenomena in many fields of science and technology including in life sciences. Computational fluid dynamic is one of numerical methods which is very popular used to describe those phenomena. In this paper we propose moving particle semi-implicit (MPS) and molecular dynamics (MD) to describe different phenomena in blood vessel. The effect of increasing the blood pressure on vessel wall will be calculate using MD methods, while the two fluid blending dynamics will be discussed using MPS. Result from the first phenomenon shows that around 80% of constriction on blood vessel make blood vessel increase and will start to leak on vessel wall, while from the second phenomenon the result shows the visualization of two fluids mixture (drugs and blood) influenced by ratio of drugs debit to blood debit. Keywords: molecular dynamic, blood vessel, fluid dynamic, movin...

  3. Wartime major venous vessel injuries.

    Science.gov (United States)

    Hudorovic, Narcis

    2008-02-01

    The aim of this study is to declare our experience and to identify the important factors that influence the mortality and morbidity in patients with combat-related penetrating wounds of the abdomen (CR-PWA) with major venous vessel injuries. Twenty-six wounded with combat-related injuries of major abdominal venous vessels, admitted in the University Clinic cardiovascular surgery department during the period from 1 August 1991 through 30 October 1995, were analyzed. Patients with concomitant injured arteries and extra-abdominal injuries (n=150; 85.2%) were excluded from this study. The Penetrating Abdominal Trauma Index (PATI) score for each patient was calculated. Fifteen patients (57.69%) sustained with PATI score greater than 25 died. The mean duration of hospitalization was 16 days (range 0-86). The average hospitalization time for those surviving their complications was 17 days with a PATI of 25 or less, and 43 days with a score more than 25. Three clinical assessments of the long-term outcome were performed after a median of about 3, 5 and 10 years, respectively. Surviving patients (42.31%) were symptom free and had normal Duplex scans as well as no other surgical related complications. Higher PATI scores, postoperative complications and reoperations exert an unfavorable effect on patient outcome. PMID:18006557

  4. Sodium recovery vessel

    International Nuclear Information System (INIS)

    Purpose: To enable to efficiently separate and recover sodium or reaction product in the secondly coolant circuit of FBR type nuclear power plant. Constitution: an upper element is disposed above a cyclone in a sodium recovery vessel, to which a gas formed by sodium-water reaction is caused to flow. Sodium and gases formed by sodium-water reaction introduced from a gas inlet of pressure open system pipeways descend downwardly as swirling stream in a cylindrical vessel within the circumferential flow channel along the outer wall of the shround surrounding the cyclone and the inner wall of the cylindrical vessel. In this case, liquid sodium is separated from the gas, falls to the bottom of the cylindrical vessel as an accumulated liquid. The gas stream passes between each of the elements in the upper element to enable separation of sodium or reaction product, as well as separated sodium and reaction product are urged to the outer circumferential side since all of the upper element and the buffer plate are arranged with their outer circumferential being lowered. (Horiuchi, T.)

  5. Pressure vessel control

    International Nuclear Information System (INIS)

    The in-service inspection machine (MIS) is robot machine which aim is to inspect, under water, the PWR type vessels (with high radiation level): inspection of the welded joints, of the coatings, detection of the defects situated under the coating, etc... This type of machine utilizes several non destructive testing technologies: ultrasonics with focused transducers, gammagraphy, television, and eddy currents

  6. Comparative study of the protective effect using hypothermic cardiopulmonary bypass and normothermic cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    HAN Pei-li; FU Qing-lin; ZHANG Xin-zhong; ZHANG-Jie; QIN Yuan-xu; CUI Yu

    2007-01-01

    Objective To explore the detrimental influence of normothermic and hypothermic cardiopulmonary by-pass during open - heart surgery on immunity function,cytokines and complements. Methods Forty patients with con-genital or rheumatic heart disease were randomized to receive the two strategies: normothermie CPB (study group) andhypothermic CPB (control group) ,20 cases in each group. Venous blood samples were collected at each time points ofpreoperation, end of CPB, day 1,4,7,14 postoperatively to examine the plasma level of IL - 2, TNF - α, C3, C4, IgG,IgM, IgA, CD3, CD4, CD8. Results IL -2 in both groups decreased significantly at day 1,4, and returned to normal atday 7 postoperatively. IL - 2 in control group was significantly lower than that in study group postoperatively. TNF - α intwo groups was all higher at time points of end of CPB,day 1,4 postoperatively;in study group,it returned to normallevel at day 7 postoperatively, whereas in control group, it was still higher at day 7 postoperatively than that before oper-ation ,and returned to normal at day 14 postoperatively. C3 in study group was significantly lower at time points of endof CPB,day 1,7 postoperatively than that in control group;C3 in both groups was all higher at time points of end ofCPB, day 1,4 postoperatively;in study group, it returned to normal level at day 7 postoperatively, whereas in controlgroup,it was still higher at day 7 postoperatively than that before operation and returned to normal at day 14 postopera-tively. CA in study group at time points of end of CPB, day 1 postoperatively was significantly lower than that in controlgroup;C4 in both groups was all lower at time points of end of CPB, day 1,4 postoperatively than that before operation.The results showed that IgA after operation in both groups was significantly lower than that before operation, and re-turned to normal at day 7 postoperatively;IgA in study group at day 1 postoperatively was higher than that in controlgroup. IgG in

  7. Cell-free cryopreserved arterial allografts from multiorgan donors: a new strategy to fabricate artificial blood vessels suited for peripheral vascular surgery

    OpenAIRE

    Papadopulos, Francesca Marzia

    2012-01-01

    Critical lower limb ischemia is a severe disease. A common approach is infrainguinal bypass. Synthetic vascular prosthesis, are good conduits in high-flow low-resistance conditions but have difficulty in their performance as small diameter vessel grafts. A new approach is the use of native decellularized vascular tissues. Cell-free vessels are expected to have improved biocompatibility when compared to synthetic and are optimal natural 3D matrix templates for driving stem cell growth and tiss...

  8. Rumen bypass nutrients: Manipulation and implications

    International Nuclear Information System (INIS)

    The feeds available for ruminants in developing countries are either agro-industrial by-products or specially grown forage crops. Many of these feeds are low in protein and require supplementation with non-protein N (NPN) to maintain efficient rumen function and digestibility. The principles for utilizing high energy, low protein feeds by ruminants are discussed in relation to the supply of NPN, the establishment of efficient rumen function, maximizing feed intake by means of supplements, and increasing total energy and protein intake by using supplements which bypass the rumen. To illustrate it the application of these principles to feeding systems based on molasses, chopped whole sugar cane and derinded sugar cane is discussed. The implications of the principles in increasing the feeding value of straw are also discussed. (author)

  9. Emergent cardiopulmonary bypass during pectus excavatum repair

    Directory of Open Access Journals (Sweden)

    Ryan Craner

    2013-01-01

    Full Text Available Pectus excavatum is a chest wall deformity that produces significant cardiopulmonary disability and is typically seen in younger patients. Minimally invasive repair of pectus excavatum or Nuss procedure has become a widely accepted technique for adult and pediatric patients. Although it is carried out through a thoracoscopic approach, the procedure is associated with a number of potential intraoperative and post-operative complications. We present a case of cardiac perforation requiring emergent cardiopulmonary bypass in a 29-year-old male with Marfan syndrome and previous mitral valve repair undergoing a Nuss procedure for pectus excavatum. This case illustrates the importance of vigilance and preparation by the surgeons, anesthesia providers as well as the institution to be prepared with resources to handle the possible complications. This includes available cardiac surgical backup, perfusionist support and adequate blood product availability.

  10. Innovative Double Bypass Engine for Increased Performance

    Science.gov (United States)

    Manoharan, Sanjivan

    Engines continue to grow in size to meet the current thrust requirements of the civil aerospace industry. Large engines pose significant transportation problems and require them to be split in order to be shipped. Thus, large amounts of time have been spent in researching methods to increase thrust capabilities while maintaining a reasonable engine size. Unfortunately, much of this research has been focused on increasing the performance and efficiencies of individual components while limited research has been done on innovative engine configurations. This thesis focuses on an innovative engine configuration, the High Double Bypass Engine, aimed at increasing fuel efficiency and thrust while maintaining a competitive fan diameter and engine length. The 1-D analysis was done in Excel and then compared to the results from Numerical Propulsion Simulation System (NPSS) software and were found to be within 4% error. Flow performance characteristics were also determined and validated against their criteria.

  11. Acrolein generation stimulates hypercontraction in isolated human blood vessels

    International Nuclear Information System (INIS)

    Increased risk of vasospasm, a spontaneous hyperconstriction, is associated with atherosclerosis, cigarette smoking, and hypertension-all conditions involving oxidative stress, lipid peroxidation, and inflammation. To test the role of the lipid peroxidation- and inflammation-derived aldehyde, acrolein, in human vasospasm, we developed an ex vivo model using human coronary artery bypass graft (CABG) blood vessels and a demonstrated acrolein precursor, allylamine. Allylamine induces hypercontraction in isolated rat coronary artery in a semicarbazide-sensitive amine oxidase activity (SSAO) dependent manner. Isolated human CABG blood vessels (internal mammary artery, radial artery, saphenous vein) were used to determine: (1) vessel responses and sensitivity to acrolein, allylamine, and H2O2 exposure (1 μM-1 mM), (2) SSAO dependence of allylamine-induced effects using SSAO inhibitors (semicarbazide, 1 mM; MDL 72274-E, active isomer; MDL 72274-Z, inactive isomer; 100 μM), (3) the vasoactive effects of two other SSAO amine substrates, benzylamine and methylamine, and (4) the contribution of extracellular Ca2+ to hypercontraction. Acrolein or allylamine but not H2O2, benzylamine, or methylamine stimulated spontaneous and pharmacologically intractable hypercontraction in CABG blood vessels that was similar to clinical vasospasm. Allylamine-induced hypercontraction and blood vessel SSAO activity were abolished by pretreatment with semicarbazide or MDL 72274-E but not by MDL 72274-Z. Allylamine-induced hypercontraction also was significantly attenuated in Ca2+-free buffer. In isolated aorta of spontaneously hypertensive rat, allylamine-induced an SSAO-dependent contraction and enhanced norepinephrine sensitivity but not in Sprague-Dawley rat aorta. We conclude that acrolein generation in the blood vessel wall increases human susceptibility to vasospasm, an event that is enhanced in hypertension

  12. Hypoglycaemia after gastric bypass: mechanisms and treatment.

    Science.gov (United States)

    Ritz, P; Vaurs, C; Barigou, M; Hanaire, H

    2016-03-01

    Hypoglycaemia after gastric bypass can be severe, but is uncommon, and is sometimes only revealed through monitoring glucose concentrations. The published literature is limited by the heterogeneity of the criteria used for diagnosis, arguing in favour of the Whipple triad with a glycaemia threshold of 55 mg/dl as the diagnostic reference. Women who lost most of their excess weight after gastric bypass, long after the surgery was performed, and who did not have diabetes before surgery are at the greatest risk. In this context, hypoglycaemia results from hyperinsulinism, which is either generated by pancreas anomalies (nesidioblastosis) and/or caused by an overstimulation of β cells by incretins, mainly glucagon-like peptide-1 (GLP-1). Glucose absorption is both accelerated and increased because of the direct communication between the gastric pouch and the jejunum. This is a post-surgical exaggeration of a natural adaptation that is seen in patients who have not undergone surgery in whom glucose is infused directly into the jejunum. There is not always a correspondence between symptoms and biological traits; however, hyperinsulinism is constant if hypoglycaemia is severe and there are neuroglucopenic symptoms. The treatment relies firstly on changes in eating habits, splitting food intake into five to six daily meals, slowing gastric emptying, reducing the glycaemic load and glycaemic index of foods, using fructose and avoiding stress at meals. Pharmacological treatment with acarbose is efficient, but other drugs still need to be validated in a greater number of subjects (insulin, glucagon, calcium channel blockers, somatostatin analogues and GLP-1 analogues). Lastly, if the surgical option has to be used, the benefits (efficient symptom relief) and the risks (weight regain, diabetes) should be weighed carefully. PMID:26508374

  13. CFD Analysis of Core Bypass Phenomena

    International Nuclear Information System (INIS)

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  14. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2010-03-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

  15. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2009-11-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  16. Instability and "Sausage-String" Appearance in Blood Vessels during High Blood Pressure

    CERN Document Server

    Alstrøm, P; Colding-Jorgensen, M; Gustafsson, F; Holstein-Rathlou, N H; Alstrom, Preben; Eguiluz, Victor M.; Colding-Jorgensen, Morten; Gustafsson, Finn; Holstein-Rathlou, Niels-Henrik

    1999-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  17. Instability and `Sausage-String' Appearance in Blood Vessels during High Blood Pressure

    OpenAIRE

    Alstrøm, P.; Eguíluz, Víctor M.; Holstein-Rathlou, Niels-Henrik

    1998-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  18. Direct ECC bypass phenomena in the MIDAS test facility during LBLOCA reflood phase

    International Nuclear Information System (INIS)

    As one of the advanced design features of the APR1400, Direct Vessel Injection(DVI) system is being considered instead of conventional Cold Leg Injection(CLI) system. It is known that the DVI system greatly enhances the reliability of the Emergency Core Cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood phase of a large-break Loss-Of-Coolant Accident (LOCA). Thus, experimental validation is under progress. In this paper, test results of direct ECC bypass performed in the steam-water test facility called MIDAS (Multi-dimensional Investigation in Downcomer Annulus Simulation) are presented. The test condition is determined, based on the preliminary analysis of TRAC code, by applying the 'modified linear scaling method' with the 1/4.93 length scale. From the tests, ECC direct bypass fraction, steam condensation rate and information on the flow distribution in the upper annulus downcomer region are obtained

  19. Direct ECC Bypass Phenomena During LBLOCA Reflood Phase Observed in the MIDAS Test: Facility

    International Nuclear Information System (INIS)

    One of the advanced design features of the APR-1400, direct vessel injection (DVI) system is being considered instead of conventional cold leg injection (CLI) system. It is known that the DVI system greatly enhances the reliability of the emergency core cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood phase of a large-break loss-of-coolant accident (LOCA). Thus, experimental validation is in progress. In this paper, test results of a direct ECC bypass performed in the steam-water test facility called MIDAS (Multi-dimensional Investigation in Downcomer Annulus Simulation) is presented. The test condition is determined, based on the preliminary analysis of TRAC code, by applying the 'modified linear scaling method' with the 1/4.93 length scale. From the tests, ECC direct bypass fraction, steam condensation rate and information on the flow distribution in the upper annulus downcomer region is obtained. (authors)

  20. Direct ECC bypass phenomena in the MIDAS test facility during LBLOCA reflood phase

    Energy Technology Data Exchange (ETDEWEB)

    Yun, B. J.; Kwon, T. S.; Euh, D. J.; Chu, I. C.; Park, W. M.; Song, C. H.; Park, J. K. [KAERI, Taejon (Korea, Republic of)

    2002-10-01

    As one of the advanced design features of the APR1400, Direct Vessel Injection(DVI) system is being considered instead of conventional Cold Leg Injection(CLI) system. It is known that the DVI system greatly enhances the reliability of the Emergency Core Cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood phase of a large-break Loss-Of-Coolant Accident (LOCA). Thus, experimental validation is under progress. In this paper, test results of direct ECC bypass performed in the steam-water test facility called MIDAS (Multi-dimensional Investigation in Downcomer Annulus Simulation) are presented. The test condition is determined, based on the preliminary analysis of TRAC code, by applying the 'modified linear scaling method' with the 1/4.93 length scale. From the tests, ECC direct bypass fraction, steam condensation rate and information on the flow distribution in the upper annulus downcomer region are obtained.

  1. Fusiform superior cerebellar artery aneurysm treated with STA-SCA bypass and trapping

    Directory of Open Access Journals (Sweden)

    Fabricio C Lamis

    2014-01-01

    Full Text Available Background: Fusiform aneurysms of cerebellar arteries are rare. Different surgical techniques to address these challenging lesions have been described, and their application depends on whether the goal is to maintain the flow in the parent vessel or to occlude it. Case Description: The authors reported a case of a fusiform aneurysm located in the lateral pontomesencephalic segment of the superior cerebellar artery (SCA in a 32-year-old man who presented with subarachnoid hemorrhage. The patient was subjected to aneurysm trapping followed by a bypass between the superficial temporal artery (STA and SCA and had an uneventful recovery. Conclusions: Although only a few cases of fusiform aneurysms in the supracerebellar artery have been reported in the literature, the treatment strategies adopted were diverse. In selected cases of patients in good neurological condition with ruptured fusiform aneurysms at the proximal segments of SCA and who have poor evidence of collateral supply, the possibility of a STA-SCA bypass with aneurysm trapping must be considered. A review of the current treatment modalities of this pathology is also presented.

  2. Alongshore sediment bypassing as a control on river mouth morphodynamics

    Science.gov (United States)

    Nienhuis, Jaap H.; Ashton, Andrew D.; Nardin, William; Fagherazzi, Sergio; Giosan, Liviu

    2016-04-01

    River mouths, shoreline locations where fluvial and coastal sediments are partitioned via erosion, trapping, and redistribution, are responsible for the ultimate sedimentary architecture of deltas and, because of their dynamic nature, also pose great management and engineering challenges. To investigate the interaction between fluvial and littoral processes at wave-dominated river mouths, we modeled their morphologic evolution using the coupled hydrodynamic and morphodynamic model Delft3D-SWAN. Model experiments replicate alongshore migration of river mouths, river mouth spit development, and eventual spit breaching, suggesting that these are emergent phenomena that can develop even under constant fluvial and wave conditions. Furthermore, we find that sediment bypassing of a river mouth develops though feedbacks between waves and river mouth morphology, resulting in either continuous bypassing pathways or episodic bar bypassing pathways. Model results demonstrate that waves refracting into the river mouth bar create a zone of low alongshore sediment transport updrift of the river mouth, which reduces sediment bypassing. Sediment bypassing, in turn, controls the river mouth migration rate and the size of the river mouth spit. As a result, an intermediate amount of river discharge maximizes river mouth migration. The fraction of alongshore sediment bypassing can be predicted from the balance between the jet and the wave momentum flux. Quantitative comparisons show a match between our modeled predictions of river mouth bypassing and migration rates observed in natural settings.

  3. Guillain–Barré Syndrome after Coronary Artery Bypass Graft Surgery:a Case Report

    Directory of Open Access Journals (Sweden)

    Manouchehr Hekmat

    2016-01-01

    Full Text Available Guillain-Barre syndrome is a neurologic disorder that may appear after infection or major surgery.  Guillian-Barre syndrome following cardiac surgery is rare and only based on case reports, and we review all of the published cases. A 52-year-old man after 5 months suffering from chest pain was referred to our hospital and underwent coronary artery bypass graft for 3 vessel disease. The patient was discharged without complication on the 5th postoperative day. He presented Guillain- Barre syndrome after 12 months. He has not completely recovered weakness of upper extremities grade 4/5 with atrophy of both upper extremities remains after 18 months. This disorder is similar to classic GBS. It is important to be alert to de novo autoimmune neurological disorders after cardiac surgery. These disorders are similar to classic autoimmune disease and treated with standard therapies.

  4. Seasonal Variation of Climatological Bypassing Flows around the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; ZHANG Renhe

    2012-01-01

    The present study investigated diagnostically the seasonal variation of the bypassing flows caused by the splitting effect of the Tibetan Plateau (TP).The relationships among the splitting bypassing flows around the TP to precipitation in China,the westerly jet stream,and the thermal status over the TP are revealed.The bypassing flows occur from the 1st to the 22nd pentad and from the 59th to the 73rd pentad,respectively,and they disappear from the 29th to the 58th pentad.They are strongest in winter from the 1st to the 22nd pentad and from the 59th to the 73rd pentad,respectively.During the rebuilding of the bypassing flows from mid-October to mid-February,they are the main cause of precipitation over southeastern China.The enhancement of the bypassing flow intensity in March cau cause the precipitation to increase in the early stage of the persistent spring rain over southeastern China.From winter to summer,the seasonal transition of the bypassing flows in the lower troposphere precedes that of the westerly jet stream axis in the upper troposphere to the west of the TP by ~4 pentads,while from summer to winter lags by ~4 pentads.The seasonal variation of the thermal status over the TP plays an important role in the bypassing flows around the TP.The strengthening of the heating over the TP weakens the bypassing flows,and the increase in cooling over the TP is related to the rebuilding and strengthening of the bypassing flows.

  5. Puerto Rico Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Puerto Rico. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  6. American Samoa Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for American Samoa. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  7. Hawaii Abandoned Vessel Inventory, Lanai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Lanai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  8. Hawaii Abandoned Vessel Inventory, Oahu

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Oahu, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  9. For-Hire Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Directory is maintained as the sample frame for the For-Hire Survey. I contains data on for-hire vessels on the Atlantic and Gulf coasts. Data include...

  10. CNMI Abandoned Vessel Inventory, Rota

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Rota. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  11. Hawaii Abandoned Vessel Inventory, Molokai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Molokai, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of...

  12. CNMI Abandoned Vessel Inventory, Saipan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Saipan. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  13. CNMI Abandoned Vessel Inventory, Tinian

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Tinian. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  14. Hawaii Abandoned Vessel Inventory, Kauai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Kauai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  15. Hawaii Abandoned Vessel Inventory, Maui

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Maui. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  16. Vessels in Transit - Web Tool

    Data.gov (United States)

    Department of Transportation — A web tool that provides real-time information on vessels transiting the Saint Lawrence Seaway. Visitors may sort by order of turn, vessel name, or last location in...

  17. Percutaneous transluminal angioplasty after bypass operations on the lower extremities

    International Nuclear Information System (INIS)

    To prevent bypass thrombosis, percutaneous transluminal angioplasty (PTA) was performed on 32 stenoses in 25 patients following vascular surgery. Seventeen patients showed 23 stenoses at the level of the anastomoses or in the bypass itself; 8 patients exhibited 9 stenoses proximal or distal to the bypass. Twenty-two patients underwent successful PTA and showed an increase in the ankle/arm Doppler index from 0.38±0.13 to 0.76±0.11 after PTA. The long-term patency rates at 6, 12 and 24 months were 75%, 57% and 39%, respectively. The reason for three unsuccessful PTAs are discussed. (orig.)

  18. Turbine trip with bypass failure analysis of Kuosheng Nuclear Power Plant using TRACE/FRAPCON/FRAPTRAN

    International Nuclear Information System (INIS)

    Kuosheng nuclear power plant (NPP) is located on the northern coast of Taiwan. Its nuclear steam supply system (NSSS) is a type of BWR/6 designed and built by General Electric on a twin unit concept. Each unit includes two loops of recirculation piping and four main steam lines, with the thermal rated power of 2894MWt. Unit 1 will start SPU (Stretch Power Uprate) from Cycle 24 and Unit 2 will start SPU from Cycle 23. The operating power will be 104.7% of the OLTP (Original Licensed Thermal Power). In order to estimate the safety of Kuosheng NPP, the methodology of Kuosheng NPP SPU safety analysis model was developed. There are three main steps considered in this methodology. The first step is the development of the Kuosheng NPP SPU TRACE model. The fuel rods steady state results of FRAPCON were used to input the TRACE model. The next step is the transient analysis of Kuosheng NPP SPU TRACE model. In this paper, the turbine trip without bypass is chosen in order to confirm the maximum pressure of vessel below the acceptance limit of 9.58 MPa. The final step is the fuel rods integrity analysis of FRAPTRAN under the above conditions. The turbine trip without bypass analysis results of TRACE indicate that the Kuosheng NPP SPU TRACE model can predict the behaviors of important parameters and the maximum vessel pressure is below the acceptance limit of 9.58 MPa. Besides, under the above conditions, the results of FRAPCON/FRAPTRAN also depict that the integrity of fuel rods are kept. The maximum of total cladding hoop strain is 0.0016, which is far less than acceptance limit 0.01, indicating that the cladding is safe in this case. And the maximum enthalpy is 52.44 cal/g, which is far less than 170 cal/g specified by the NRC NUREG-0800 standard review plan. (author)

  19. Reactor vessel stud closure system

    International Nuclear Information System (INIS)

    A quick-acting stud tensioner apparatus for enabling the loosening or tightening of a stud nut on a reactor vessel stud. The apparatus is adapted to engage the vessel stud by closing a gripper around an upper end of the vessel stud when the apparatus is seated on the stud. Upon lifting the apparatus, the gripper releases the vessel stud so that the apparatus can be removed

  20. Pressure vessel design manual

    Energy Technology Data Exchange (ETDEWEB)

    Moss, D.R.

    1987-01-01

    The first section of the book covers types of loadings, failures, and stress theories, and how they apply to pressure vessels. The book delineates the procedures for designing typical components as well as those for designing large openings in cylindrical shells, ring girders, davits, platforms, bins and elevated tanks. The techniques for designing conical transitions, cone-cylinder intersections, intermediate heads, flat heads, and spherically dished covers are also described. The book covers the design of vessel supports subject to wind and seismic loads and one section is devoted to the five major ways of analyzing loads on shells and heads. Each procedure is detailed enough to size all welds, bolts, and plate thicknesses and to determine actual stresses.

  1. Reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Research and development activities related to reactor pressure vessel steels during 1997 are reported. The objectives of activities of the Belgian Nuclear Research Centre SCK/CEN in this domain are: (1) to develop enhanced surveillance concepts by applying micromechanics and fracture-toughness tests to small specimens, and by performing damage modelling and microstructure characterization; (2) to demonstrate a methodology on a broad database; (3) to achieve regulatory acceptance and industrial use

  2. JPDR vessel steel examination

    International Nuclear Information System (INIS)

    There is a need to validate the results of irradiation effects research by the examination of material taken directly from the wall of a pressure vessel which has been irradiated during normal service. This task has been included with the HSSI Program to provide just such an evaluation of material from the wall of the pressure vessel from the JPDR. The JPDR was a small BWR that began operation in 1963. It operated until 1976, accumulating ∼17,000 h of operation, of which a little over 14,000 h were with the original 45-MWTh core, and the remaining fraction, late in life, with an upgraded 90-MWTh core. The pressure vessel of the JPDR, fabricated from A 302, grade B, modified steel with an internal weld overlay cladding of 304 stainless steel, is approximately 2 m ID and 73 mm thick. It was fabricated from two shell halves joined by longitudinal seam welds located 180 degrees from each other. The rolling direction of the shell plates is parallel to the axis of the vessel. It operated at 273 degrees C and reached a maximum fluence of about 2.3 x 1018 n/cm2 (> 1 MeV). The impurity contents in the base metal are 0.10 to 0.11% Cu and 0.010 to 0.017% P with a nickel content of 0.63 to 0.65%. Impurity contents of the weld metal are 0.11 to 0.14% Cu and 0.025 to 0.039% P with a nickel content of 0.59%

  3. Off-pump versus on-pump coronary artery bypass grafting for ischaemic heart disease

    DEFF Research Database (Denmark)

    Møller, Christian H; Penninga, Luit; Wetterslev, Jørn; Steinbrüchel, Daniel A; Gluud, Christian

    2012-01-01

    Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear.......Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear....

  4. Assessment of MARS 2.0 for direct DVI bypass during LBLOCA reflood using KAERI air-water DVI tests

    International Nuclear Information System (INIS)

    MARS code has been assessed for the direct ECC (Emergency Core Cooling) bypass that occurs during LBLOCA reflood of KNGR (Korean Next Generation Reactor) using the KAERI air-water DVI (Direct Vessel Injection) tests that are 1/50 scale-down tests simulating the LBLOCA reflood of KNGR. Assessment matrix is selected for the single and double DVI configurations with typical LBLOCA reflood conditions, that is, DVI injection velocity of 1.0 ∼ 1.6 m/sec and air injection velocity of 20 ∼ 35 m/sec. First, the MARS calculation is adjusted to match the DVI film distribution with the 1/50 scale test results, then the code assessments are carried out for the selected direct DVI bypass tests using the adjusted DVI film distribution. From the assessments, it has been found that the MARS is capable of predicting the direct DVI bypass phenomena as well as the multi-dimensional thermal hydraulics in the downcomer

  5. CFD simulation of hemodynamics in sequential and individual coronary bypass grafts based on multislice CT scan datasets.

    Science.gov (United States)

    Hajati, Omid; Zarrabi, Khalil; Karimi, Reza; Hajati, Azadeh

    2012-01-01

    There is still controversy over the differences in the patency rates of the sequential and individual coronary artery bypass grafting (CABG) techniques. The purpose of this paper was to non-invasively evaluate hemodynamic parameters using complete 3D computational fluid dynamics (CFD) simulations of the sequential and the individual methods based on the patient-specific data extracted from computed tomography (CT) angiography. For CFD analysis, the geometric model of coronary arteries was reconstructed using an ECG-gated 64-detector row CT. Modeling the sequential and individual bypass grafting, this study simulates the flow from the aorta to the occluded posterior descending artery (PDA) and the posterior left ventricle (PLV) vessel with six coronary branches based on the physiologically measured inlet flow as the boundary condition. The maximum calculated wall shear stress (WSS) in the sequential and the individual models were estimated to be 35.1 N/m(2) and 36.5 N/m(2), respectively. Compared to the individual bypass method, the sequential graft has shown a higher velocity at the proximal segment and lower spatial wall shear stress gradient (SWSSG) due to the flow splitting caused by the side-to-side anastomosis. Simulated results combined with its surgical benefits including the requirement of shorter vein length and fewer anastomoses advocate the sequential method as a more favorable CABG method. PMID:23365974

  6. Radioactive material storage vessel

    International Nuclear Information System (INIS)

    In a radioactive material storage vessel having a single sealing boundary in the cylindrical portion and a double sealing boundary in the lid portion, and the outer circumference of the vessel being cooled by air, in which difference is made between the pressure in a radioactive material storage chamber and the pressure in an intermediate chamber present between a primary sealing lid and a secondary sealing lid. A valve is disposed to the primary sealing lid, which breaks the sealing between the radioactive material containing chamber and the intermediate chamber when the difference between the pressure of the containing chamber and that of the intermediate chamber is reduced to lower than a predetermined value, and a sensor for detecting pressure change in the intermediate chamber is disposed to the secondary sealing lid. In addition, a shrinkable member having at least a predetermined length and an extensible length is disposed to the primary sealing lid, and a displacement sensor capable of detecting the change of the length of the shrinkable member is disposed to the secondary sealing lid. Then, when the sealing boundary at the cylinder portion of the radioactive material containing chamber should be broken in the radioactive material storage vessel, it can be detected. (N.H.)

  7. Valve Replacement Performed on the Beating Heart with Continuous Retrograde Coronary Sinus Isothermic Blood Perfusion Combined with Coronary Bypass

    Directory of Open Access Journals (Sweden)

    Orhan Saim Demirtürk

    2012-12-01

    Full Text Available An operation on the beating heart was planned for a 60-year-old woman who applied to our clinic with aortic stenosis, three vessel coronary artery disease and poor left ventricular function. There are reports about beating heart valve surgery perfomed alone or combined with coronary artery bypass operations using continuous retrograde coronary sinus isothermic blood perfusion in patients with poor ventricle. We performed a coronary revascularization process for three-vessel disease on the pump beating heart and aortic valve replacement under cross-clamp using continuous retrograde coronary sinus isothermic blood perfusion in the same session. She was discharged on the sixth postoperative day after an uneventful recovery. She is well and active 24 months after the operation. Valve replacement using the retrograde coronary sinus isothermic blood perfusion technique due to its protective effect on the already borderline myocardial functions in patients with poor ventricles is a useful and clinically successful method.

  8. Evaluation of contrast wash-in and peak enhancement in adenosine first pass perfusion CMR in patients post bypass surgery

    Directory of Open Access Journals (Sweden)

    Schnackenburg Bernhard

    2010-05-01

    Full Text Available Abstract Background Adenosine first pass perfusion cardiovascular magnetic resonance (CMR yields excellent results for the detection of significant coronary artery disease (CAD. In patients with coronary artery bypass grafts (CABG the kinetics of a contrast bolus may by altered only due to different distances through the bypass grafts compared to native vessels, thereby possibly imitating a perfusion defect. The aim of the study was to evaluate semiquantitative perfusion parameters in order to assess possible differences in epicardial contrast kinetics in areas supplied by native coronaries and CABG, both without significant stenosis. Methods Twenty patients with invasive exclusion of significant CAD (control group and 38 patients with CABG without angiographically significant (≥50% stenosis in unbypassed coronaries or grafts were retrospectively included in the study. They underwent adenosine first pass (0.05 mmol/kg Gd-DTPA perfusion (3 short axis views/heart beat and late gadolinium enhancement (LGE imaging 1 day before invasive coronary angiography. Areas perfused by native coronaries and/or the different bypasses were identified in X-ray angiography using the 16 segment model. In each of these areas upslope and maximal signal intensity (SImax relative to the left ventricular parameters, time to 50% maximal signal intensity (TSI50%max and time to maximal signal intensity (TSImax were calculated. Results In areas perfused by coronary arteries with bypasses compared to native coronaries relative upslope and relative SImax did not show a significant difference. TSI50%max and TSImax in native coronaries and bypasses were 7.2s ± 1.9s vs. 7.5s ± 1.9s (p max resulted in a significant (p Conclusion Adenosine perfusion CMR in patients post CABG may be associated with a short delay in contrast arrival. However, once the contrast is in the myocardium there is similar wash-in kinetics and peak enhancement. Therefore, since the delay is only short

  9. An experimental study on minimally occlusive laser-assisted vascular anastomosis in bypass surgery: the importance of temperature monitoring during laser welding procedures.

    Science.gov (United States)

    Esposito, G; Rossi, F; Puca, A; Albanese, A; Sabatino, G; Matteini, P; Lofrese, G; Maira, G; Pini, R

    2010-01-01

    Laser welding has been proposed as an alternative technique to conventional stitching in microvascular anastomosis, with the advantages of improving the vascular healing process and reducing the risk of malfunction of a bypass. Our group recently proposed a laser-assisted end-to-side anastomotic technique, providing the advantages of laser welding and reducing the occlusion time of the recipient vessel, that is important in neurosurgical bypass procedures, in order to reduce the risk of cerebral ischemia. This in vivo study focuses on the control of the temperature dynamics developing in the welded tissue. A jugular vein graft was harvested and implanted on the rabbit carotid artery by means of two end-to-side anastomosis. Laser welding procedure was then carried out to implant the bypass. A real-time monitoring of the temperature during welding was performed with an infrared thermocamera, in order to control the laser-induced heating effect on the external surface of the vessel walls. The temperature analysis highlighted the dynamic of the heating effect in space and time and enabled us to define an optimal temperature range in operative conditions. The temperature control provided safe tissue heating confined within the directly irradiated area, with negligible damage to surrounding tissues, as well as effective sealing and welding of the vessel edges at the anastomotic sites. The average occlusion time of the carotid artery was about 11 minutes. After a follow-up of 30 days, all the bypasses were patent and no signs of thrombosis or leak point pressure were present, thus confirming the safety of this laser-assisted anastomotic procedure. PMID:20846478

  10. Apicoaortic Valve Conduit for a Patient with Aortic Valve Stenosis and Patent Coronary Bypass Grafts Using Cardiopulmonary Bypass.

    Science.gov (United States)

    Shackelford, Anthony G; Relle, Margaret A; Lombardi, Sarah A

    2015-12-01

    In adults over 65 years of age, aortic valve stenosis has been found to be present in 2-9% within this group. Furthermore, aortic valve replacements in patients whom have had a previous coronary artery bypass grafting surgery have a mortality rate as high as 18%. A non-conventional effective surgical approach of bypassing the aortic valve by inserting an apicoaortic valve conduit (AVC) connecting the left ventricular apex to the descending thoracic aorta has been previously documented. We describe the case of a successful implantation of an AVC in a 64-year-old Caucasian male using cardiopulmonary bypass. PMID:26834287

  11. Reusing the patent internal mammary artery as a conduit in redo coronary artery bypass surgery.

    Science.gov (United States)

    Nwaejike, Nnamdi; Tennyson, Charlene; Mosca, Roberto; Venkateswaran, Rajamiyer

    2016-03-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, in patients with previous internal mammary artery/internal thoracic artery (ITA) grafts, can the internal mammary artery/ITA be reused/recycled in redo coronary artery bypass surgery? Fourteen papers were found using the reported search of which 10 represented the best evidence to answer the clinical question. There was variation in patient selection, the number of patients reported, outcome measures recorded, and methods and duration of follow-up. The results were mostly in favour of using a recycled ITA when it could be safely harvested. Most studies were retrospective. One large series of 60 patients who underwent redo coronary artery bypass grafting (CABG) using previously implanted ITAs had a mean time to reoperation of 117 ± 68 months. They reported no operative deaths; no patients required further or subsequent target vessel revascularization; 30-day mortality was 8.3% and myocardial infarction rate was 3%. Another two series of 16 and 12 patients underwent recycling of arterial grafts during coronary artery revascularization with no perioperative deaths in either. Postoperative angiography was performed in 10 patients in one of these studies, which showed excellent flow in all redone left internal thoracic artery (LITA) grafts. One study reported results from a prospective cohort of 9 patients who underwent redo coronary artery bypass grafting. Interval between operations was between 1 and 132 months. There was no perioperative mortality, but 1 patient required reintervention (to an interposition vein graft). A further study of 4 patients who underwent redo CABG using ITAs that were patent but with severe stenosis at the distal anastomosis had no mortality. Postoperative angiography showed patency of all grafts. There have also been 4 case reports on reusing the ITA/ITA in redo CABG with no damage to the reused LITA, no perioperative

  12. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... to check their blood sugar several times a day. Other problems that patients with morbid obesity have ... a lap band and he’s discharged the next day. With the gastric bypass, the patient comes in ...

  13. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... and are morbidly obese have higher incidents of heart problems. The other things that we see are ... used for multiple surgical procedures. It’s used for heart procedures, the CABG, coronary artery bypass, valve procedures, ...

  14. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... the gastric bypass Roux-en-Y is a superior procedure than the lap band. That given, we ... of the robot has been shown to be superior to the laparoscopic cases, that this will also ...

  15. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... Anthony Gonzalez, and welcome to South Miami Hospital. We’re here for a live webcast, a fully robotic gastric bypass, as I mentioned, we’re in the operating room at South Miami ...

  16. Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy

    DEFF Research Database (Denmark)

    Patti, M E; McMahon, G; Mun, E C;

    2005-01-01

    AIMS/HYPOTHESIS: Postprandial hypoglycaemia following gastric bypass for obesity is considered a late manifestation of the dumping syndrome and can usually be managed with dietary modification. We investigated three patients with severe postprandial hypoglycaemia and hyperinsulinaemia unresponsive...

  17. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... you a detailed account of how the operation works. During that time, I’d like to answer ... you’ll understand it. Basically, the gastric bypass works on two different principals for weight loss, one ...

  18. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... The feet are in this direction. And the robot is brought and docked over the patient’s body ... this location where I will be using the robot to perform this fully robotic gastric bypass. So ...

  19. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... Health South Florida Miami, FL May 20, 2010 I am Dr. Anthony Gonzalez, and welcome to South ... live webcast, a fully robotic gastric bypass, as I mentioned, we’re in the operating room at ...

  20. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... needs to be bypassed. So I feel more confident that I can go ahead and start taking ... more so as people become more familiar and confident with their skills. 00:39:31 JOHN PENNOCK, ...

  1. Alveolar proteinosis lung lavage using partial cardiopulmonary bypass.

    OpenAIRE

    Freedman, A P; Pelias, A; Johnston, R F; Goel, I P; Hakki, H I; Oslick, T; Shinnick, J P

    1981-01-01

    An adult case of pulmonary alveolar proteinosis presented with an arterial oxygen tension of 27 mmHg (3.6 kPa) while breathing air. Dangerous hypoxaemia during lung lavage was avoided by using partial cardiopulmonary bypass.

  2. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... Loss Surgery: The Fully Robotic Gastric Bypass Baptist Health South Florida Miami, FL May 20, 2010 I ... study in 1991 at the National Institute of Health in Washington, D.C. And what they looked ...

  3. Antiplatelet therapy at the time of coronary artery bypass grafting

    DEFF Research Database (Denmark)

    Kremke, Michael; Jensen, Mariann Tang; Bak, Mikkel; Kristensen, Katrine Lawaetz; Hindsholm, Karsten; Andreasen, Jan Jesper; Hjortdal, Vibeke; Jakobsen, Carl-Johan

    2013-01-01

    OBJECTIVES: The purpose of this multicentre cohort study was to examine the relationship between antiplatelet therapy (APT) at the time of coronary artery bypass grafting (CABG) and postoperative bleeding complications, transfusion requirements and adverse cardiovascular events. METHODS: A matched...

  4. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... later, there was laparoscopic gastric bypass surgery. The learning curve, which is the time that it takes for the surgeon to learn surgery from open to laparoscopic, used to be ...

  5. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... Loss Surgery: The Fully Robotic Gastric Bypass Baptist Health South Florida Miami, FL May 20, 2010 I ... robotic prostatectomy, which is probably the standard of care today for prostate cancer. This is our eighth ...

  6. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass Baptist Health South Florida Miami, FL May 20, 2010 I am Dr. Anthony Gonzalez, and welcome to South Miami Hospital. We’ ...

  7. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... gastrectomy. Another question is, “Does gastric bypass eliminate diabetes?” The morbidly obese patients that we see are those patients that have diabetes mellitus type II, and that’s diabetes associated with ...

  8. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... of reinforce this. This has been a really beautiful case. There’s really no bleeding, even though we ... on BAPTISTHEALTH.NET and joining us for this beautiful fully robotic gastric bypass. I hope that Dr. ...

  9. Association of sex with patency of femorodistal bypass grafts

    DEFF Research Database (Denmark)

    Watson, H R; Schroeder, T V; Simms, M H;

    2000-01-01

    There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome....

  10. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... we have an added dimension, and the depth perception is incredible and just aids the surgery a ... later, there was laparoscopic gastric bypass surgery. The learning curve, which is the time that it takes ...

  11. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... gastric bypass. So without further adieu, let me send you out, right outside our doors to my ... everything else that’s going into it, it will send the same signal to the brain that you’ ...

  12. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... Harrisburg Hospital campus. We are going to witness a robot-assisted minimally invasive coronary artery bypass surgery ... you're starting to do and maybe give a little background on the patient's condition? 00:00: ...

  13. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... later, there was laparoscopic gastric bypass surgery. The learning curve, which is the time that it takes ... that you can do it proficiently; however the learning curve with robotic surgery is much shorter. In ...

  14. Collider bypass diode thermal simulations and measurements for the SSCL

    Energy Technology Data Exchange (ETDEWEB)

    Rostamzadeh, C.; Tool, G.

    1993-05-01

    Warm bypass diodes will be used as a component of a quench protection system to bypass an exponentially decaying current of 36 sec. time constant and peak current of 7000 A. Temperature excursions due to approximately 252 Kilo Ampere Sec. are studied using ANSYS, a finite element analysis program. A parabolic current waveform of similar energy but higher MIITs (1058 MIIT) was applied to the bypass circuit and temperature excursion was measured at various locations. The procedure of current waveform generation and thermal measurements is illustrated in this paper. A comparison of simulation technique with actual measurements confirms the accuracy of the bypass diode assembly model. This assembly is installed at the SSC half-cell string test facility and results are extremely encouraging.

  15. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... done in two dimensions. Here we have an added dimension, and the depth perception is incredible and ... just a restrictive type of procedure. There’s no combined procedure like with the gastric bypass. So the ...

  16. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... operative procedure, the live procedure, you’ll understand it. Basically, the gastric bypass works on two different ... a small portion of the stomach and divide it from the rest of the stomach, and that’s ...

  17. Value of Optical Bypass in Packet Ring Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper firstly examines the value of optical bypass scheme in packet ring networks. An Integer Linear Program (ILP) formulation is presented and analytical results under different traffic patterns are given.

  18. Normoxic and Hyperoxic Cardiopulmonary Bypass in Congenital Heart Disease

    OpenAIRE

    2014-01-01

    Cyanotic congenital heart disease comprises a diverse spectrum of anatomical pathologies. Common to all, however, is chronic hypoxia before these lesions are operated upon when cardiopulmonary bypass is initiated. A range of functional and structural adaptations take place in the chronically hypoxic heart, which, whilst protective in the hypoxic state, are deleterious when the availability of oxygen to the myocardium is suddenly improved. Conventional cardiopulmonary bypass delivers hyperoxic...

  19. Electrical failure during cardiopulmonary bypass: a critical moment.

    Science.gov (United States)

    Durukan, Ahmet Baris; Gurbuz, Hasan Alper; Ozcelik, Gokhan; Yorgancioglu, Cem

    2016-06-01

    Electrical failure during cardiopulmonary bypass is a crisis situation for the cardiac surgical team. Fortunately, it has a low incidence with low morbidity and mortality rates. Notwithstanding, institutional preventative and management measures should be taken. Here, we report a case of electrical failure during cardiopulmonary bypass, which was successfully managed during the surgery, allowing the patient to recover uneventfully. These unwanted complications can only be managed by promoting awareness and putting in place strategies against them. PMID:27516788

  20. Bypass flow computations on the LOFA transient in a VHTR

    International Nuclear Information System (INIS)

    Bypass flow in the prismatic gas-cooled very high temperature reactor (VHTR) is not intentionally designed to occur, but is present in the gaps between graphite blocks. Previous studies of the bypass flow in the core indicated that the cooling provided by flow in the bypass gaps had a significant effect on temperature and flow distributions for normal operating conditions. However, the flow and heat transports in the core are changed significantly after a Loss of Flow Accident (LOFA). This study aims to study the effect and role of the bypass flow after a LOFA in terms of the temperature and flow distributions and for the heat transport out of the core by natural convection of the coolant for a 1/12 symmetric section of the active core which is composed of images and mirror images of two sub-region models. The two sub-region models, 9 × 1/12 and 15 × 1/12 symmetric sectors of the active core, are employed as the CFD flow models using computational grid systems of 70.2 million and 117 million nodes, respectively. It is concluded that the effect of bypass flow is significant for the initial conditions and the beginning of LOFA, but the bypass flow has little effect after a long period of time in the transient computation of natural circulation. -- Highlights: • Effect of with/without bypass flow through gaps between hexagonal blocks is studied. • Role of natural convection by the bypass flow after a loss of flow accident. • Two regions of the one-twelfth symmetric sector of the active core are in CFD models. • 70.2 million cell mesh employed for CFD computations with 15 and 9 × 1/12 sectors. • The reference model is based on modular high temperature gas-cooled reactor (MHTGR)

  1. Bypass Selection for Control of Heat Exchanger Network

    Institute of Scientific and Technical Information of China (English)

    SUN Lin; LUO Xionglin; HOU Benquan; BAI Yujie

    2013-01-01

    Considering the flexibility and controllability of heat exchanger networks (HENs),bypasses are widely used for effective control of process stream target temperatures.However,the optimal location for the bypass is generally difficult to design with the trade-off between controllability and capital investments.In this paper,based on the steady-state model of heat exchanger networks the optimal bypass location was firstly selected by iteratively calculating the non-square Relative Gain Array (ns-RGA).To simplify the calculation process,rules of bypass selection were also proposed.In order to evaluate this method,then,the structural controllability of heat exchanger networks was analyzed.With both the consideration of the controllability and capital investments,the bypasses locations were finally selected.A case study on the HEN in Crude Distillation Unit was presented in which the ns-RGA and structural controllability were used to select bypasses and also to evaluate the results.

  2. Psychological characteristics and associations with weight outcomes two years after gastric bypass surgery

    DEFF Research Database (Denmark)

    Beck, Nina N; Mehlsen, Mimi; Støving, René Klinkby

    2012-01-01

    This study investigated symptoms of eating disorder, depression, and anxiety among Roux-en-Y gastric bypass patients two years after surgery, and the relationship between these characteristics and weight loss. Respondents completed assessment questionnaires including Eating Disorder Inventory-2...... that knowledge of the potential influence of eating disorder symptoms on outcomes after bariatric surgery is needed in order to optimize weight outcomes following surgery....... (EDI-2), Harvard Anxiety and Depression Scale (HADS), and questions related specifically to binge eating. Forty-five patients (8 men, 37 women) out of 65 (67%) responded. Scores were significant higher on impulse regulation, interoceptive awareness, ineffectiveness, maturity fears and interpersonal...

  3. Variations in dietary intake after bypass surgery for obesity. Possible relation to development of fatty liver after jejunoileal bypass

    Energy Technology Data Exchange (ETDEWEB)

    Rogus, J.; Blumenthal, S.A.

    1981-01-01

    Consumption of nutrients and food energy was compared, with concomitant chemical and radiologic measurements of hepatic fat content, preoperatively and postoperatively in 25 patients who underwent gastric or jejunoileal bypass for obesity. Patients in the two operative groups ingested similar quantities of food before surgery. After surgery, caloric intake from all sources decreased in both groups but to a significantly greater extent in the gastric bypass patients. During the first six months postoperatively, the 13 gastric bypass patients showed no changes in hepatic fat content, whereas substantial increases in liver fat uniformly occurred in the 12 patients who had jejunoileal bypasses. It is suggested that dietary carbohydrate may have contributed to the accretion of liver fat in these 12 patients.

  4. Vessel enhancing diffusion: a scale space representation of vessel structures.

    Science.gov (United States)

    Manniesing, Rashindra; Viergever, Max A; Niessen, Wiro J

    2006-12-01

    A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature. PMID:16876462

  5. Radial artery for coronary artery bypass grafting: does proximal anastomosis to the aorta or left internal mammary artery achieve better patency?

    Science.gov (United States)

    Watson, Robert A; Hamza, Mustafa; Tsakok, Teresa M; Tsakok, Maria T

    2013-12-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'in coronary artery bypass grafting using radial artery grafts, does proximal anastomosis to the aorta or left internal mammary artery achieve better patency'. Altogether >183 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Radial artery grafts typically have a narrower lumen than vein grafts, and as such there is some concern that anastomosing them directly to the aorta during coronary artery bypass grafting (CABG) may impair graft patency. As such, some surgeons prefer to anastomose radial artery grafts to a second-order vessel such as the left internal mammary artery (LIMA). We sought to assess the evidence for this. A handful of papers directly addressing the issue of the effect of the site of proximal anastomosis on graft patency were found, with three showing no significant difference. One such study reported an insignificant difference in angiographic patency at 32 months postoperatively, with 94.1% of off-aorta grafts remaining patent vs 87.2% of off-LIMA grafts (p = 0.123). However, a large-scale well-designed study was able to demonstrate a statistically significant difference at five years postoperatively, with 74.3% of off-aorta grafts patent, compared with 65.2% of off-LIMA (p = 0.004). Nonetheless, a number of papers that report patency for either off-aorta or off-LIMA grafts give comparable figures for each technique. Additionally, different centres and investigators report very different patency results for grafts that have the same site of proximal anastomosis. One centre was able to achieve patency rates for off-LIMA grafts of 88% up to a mean of 7.7 years postoperatively while another centre reported a patency rate

  6. Vessel enhancing diffusion: a scale space representation of vessel

    OpenAIRE

    Manniesing, Rashindra; Viergever, M.A; Niessen, Wiro

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffus...

  7. Design of pressure vessels using shape optimization: An integrated approach

    International Nuclear Information System (INIS)

    Previous papers related to the optimization of pressure vessels have considered the optimization of the nozzle independently from the dished end. This approach generates problems such as thickness variation from nozzle to dished end (coupling cylindrical region) and, as a consequence, it reduces the optimality of the final result which may also be influenced by the boundary conditions. Thus, this work discusses shape optimization of axisymmetric pressure vessels considering an integrated approach in which the entire pressure vessel model is used in conjunction with a multi-objective function that aims to minimize the von-Mises mechanical stress from nozzle to head. Representative examples are examined and solutions obtained for the entire vessel considering temperature and pressure loading. It is noteworthy that different shapes from the usual ones are obtained. Even though such different shapes may not be profitable considering present manufacturing processes, they may be competitive for future manufacturing technologies, and contribute to a better understanding of the actual influence of shape in the behavior of pressure vessels. - Highlights: → Shape optimization of entire pressure vessel considering an integrated approach. → By increasing the number of spline knots, the convergence stability is improved. → The null angle condition gives lower stress values resulting in a better design. → The cylinder stresses are very sensitive to the cylinder length. → The shape optimization of the entire vessel must be considered for cylinder length.

  8. Design of pressure vessels using shape optimization: An integrated approach

    Energy Technology Data Exchange (ETDEWEB)

    Carbonari, R.C., E-mail: ronny@usp.br [Department of Mechatronic Engineering, Escola Politecnica da Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231 Sao Paulo, SP 05508-900 (Brazil); Munoz-Rojas, P.A., E-mail: pablo@joinville.udesc.br [Department of Mechanical Engineering, Universidade do Estado de Santa Catarina, Bom Retiro, Joinville, SC 89223-100 (Brazil); Andrade, E.Q., E-mail: edmundoq@petrobras.com.br [CENPES, PDP/Metodos Cientificos, Petrobras (Brazil); Paulino, G.H., E-mail: paulino@uiuc.edu [Newmark Laboratory, Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Av., Urbana, IL 61801 (United States); Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 158 Mechanical Engineering Building, 1206 West Green Street, Urbana, IL 61801-2906 (United States); Nishimoto, K., E-mail: knishimo@usp.br [Department of Naval Architecture and Ocean Engineering, Escola Politecnica da Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231 Sao Paulo, SP 05508-900 (Brazil); Silva, E.C.N., E-mail: ecnsilva@usp.br [Department of Mechatronic Engineering, Escola Politecnica da Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231 Sao Paulo, SP 05508-900 (Brazil)

    2011-05-15

    Previous papers related to the optimization of pressure vessels have considered the optimization of the nozzle independently from the dished end. This approach generates problems such as thickness variation from nozzle to dished end (coupling cylindrical region) and, as a consequence, it reduces the optimality of the final result which may also be influenced by the boundary conditions. Thus, this work discusses shape optimization of axisymmetric pressure vessels considering an integrated approach in which the entire pressure vessel model is used in conjunction with a multi-objective function that aims to minimize the von-Mises mechanical stress from nozzle to head. Representative examples are examined and solutions obtained for the entire vessel considering temperature and pressure loading. It is noteworthy that different shapes from the usual ones are obtained. Even though such different shapes may not be profitable considering present manufacturing processes, they may be competitive for future manufacturing technologies, and contribute to a better understanding of the actual influence of shape in the behavior of pressure vessels. - Highlights: > Shape optimization of entire pressure vessel considering an integrated approach. > By increasing the number of spline knots, the convergence stability is improved. > The null angle condition gives lower stress values resulting in a better design. > The cylinder stresses are very sensitive to the cylinder length. > The shape optimization of the entire vessel must be considered for cylinder length.

  9. The Effects of Exercise Cardiac Rehabilitation on Anxiety, Depression and Quality of Life in Coronary Artery Bypass Grafting Patients

    OpenAIRE

    A. Yalfani; F. Nazem; R. Safiarian; M. Jargeh

    2012-01-01

    Introduction & Objective: Despite advancement in technology such as coronary artery bypasses grafting (CABG) prevalence of anxiety and depression remain high after cardiac events, which have been found to influence recovery process, recurrent cardiac events and patients’ quality of life. Cardiac Rehabilitation (CR) as part of secondary prevention aims to improve patients’ physical, psychological and quality of life (QoL) status. As there is lack of study in this area in Iran, the present stud...

  10. An automated vessel segmentation of retinal images using multiscale vesselness

    International Nuclear Information System (INIS)

    The ocular fundus image can provide information on pathological changes caused by local ocular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. Automated analysis and interpretation of fundus images has become a necessary and important diagnostic procedure in ophthalmology. The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. In this paper, we introduce an implementation of the anisotropic diffusion which allows reducing the noise and better preserving small structures like vessels in 2D images. A vessel detection filter, based on a multi-scale vesselness function, is then applied to enhance vascular structures.

  11. Lymph flow regulates collecting lymphatic vessel maturation in vivo

    OpenAIRE

    Sweet, Daniel T.; Jiménez, Juan M.; Chang, Jeremy; Hess, Paul R.; Mericko-Ishizuka, Patricia; Fu, Jianxin; Xia, Lijun; Davies, Peter F.; Kahn, Mark L.

    2015-01-01

    Fluid shear forces have established roles in blood vascular development and function, but whether such forces similarly influence the low-flow lymphatic system is unknown. It has been difficult to test the contribution of fluid forces in vivo because mechanical or genetic perturbations that alter flow often have direct effects on vessel growth. Here, we investigated the functional role of flow in lymphatic vessel development using mice deficient for the platelet-specific receptor C-type lecti...

  12. Premature coronary artery disease in systemic lupus erythematosus with extensive reocclusion following coronary artery bypass surgery.

    Science.gov (United States)

    D Agate, David J; Kokolis, Spyros; Belilos, Elise; Carsons, Steven; Andrieni, Julia; Argyros, Thomas; Glasser, Lynne A; Dangas, George

    2003-03-01

    A 21-year-old woman with a history of systemic lupus erythematosus (SLE) presented to the emergency room with a chief complaint of substernal chest pain and palpitations. She had undergone a four-vessel coronary artery bypass graft operation with separate saphenous vein grafts to the left anterior descending (LAD), obtuse marginal (OM) 1 and 2, and distal right coronary arteries (RCA) 8 months prior to admission. The patient underwent angiography of the coronary vessels, which showed severe diffuse disease with a long, 90% narrowing of the vein graft to the LAD and closed vein grafts to OM1 and OM2. The RCA graft showed mild diffuse disease. An intervention was done in which the LAD was stented twice with subsequent TIMI 3 flow. Advances in medical therapy and a better understanding of the disease have contributed to a dramatic improvement in the long-term survival of patients with SLE. However, despite the overall long-term improvement, coronary artery disease remains a major cause of morbidity and mortality with an incidence of approximately nine-fold greater than would be expected for this population. PMID:12612393

  13. Reactor vessel stud thread protector

    International Nuclear Information System (INIS)

    This patent describes a stud thread protector for a nuclear reactor pressure vessel. The vessel has a removable closure head, the closure head being sealingly engaged with the pressure vessel by a plurality of stud bolts, an upper end thereof having a threaded section for threadingly engaging a nut and a vertical bore being disposed within the stud bolt. The stud thread protector encloses the exposed upper portion of the bolt and associated nut projecting above the closure head. The reactor vessel stud thread protector is comprised of: a tubular wall portion being opened at its lower end and substantially closed at its upper end; a drip pan associated with the outer surface of the protector, the drip pan being disposed radially inwardly with respect to the outer periphery of the vessel head, whereby the drip pan collects any fluid being emitted from the reactor vessel; and means for fastening the stud thread protector to an associated stud

  14. Study on vessels' seismic buckling

    International Nuclear Information System (INIS)

    Inspection on Kashiwazaki-Kariwa Nuclear Power Station after the Niigateken Chuetsu-oki Earthquake in 2007 observed obvious buckling in some fluid storage vessels, the filtrate tanks and de-ionized Water tanks. All vessels with buckling belong to Seismic class C. Contrary the other vessels such as Diesel tanks showed no damage. Those phenomena presumably are brought about by differences in the vessels' condition (Vessels geometries, Fluid weight, etc.) and the seismic load on each vessel. In this study, the elephant's foot buckling occurred on the filtrate tank was simulated by FEM analysis of the large displacement elastic-plastic model with the recorded time history of seismic acceleration. The same analysis on the diesel was conducted tank to see that no damage took place also in the analysis. (author)

  15. Annular MHD Physics for Turbojet Energy Bypass

    Science.gov (United States)

    Schneider, Steven J.

    2011-01-01

    The use of annular Hall type MHD generator/accelerator ducts for turbojet energy bypass is evaluated assuming weakly ionized flows obtained from pulsed nanosecond discharges. The equations for a 1-D, axisymmetric MHD generator/accelerator are derived and numerically integrated to determine the generator/accelerator performance characteristics. The concept offers a shockless means of interacting with high speed inlet flows and potentially offers variable inlet geometry performance without the complexity of moving parts simply by varying the generator loading parameter. The cycle analysis conducted iteratively with a spike inlet and turbojet flying at M = 7 at 30 km altitude is estimated to have a positive thrust per unit mass flow of 185 N-s/kg. The turbojet allowable combustor temperature is set at an aggressive 2200 deg K. The annular MHD Hall generator/accelerator is L = 3 m in length with a B(sub r) = 5 Tesla magnetic field and a conductivity of sigma = 5 mho/m for the generator and sigma= 1.0 mho/m for the accelerator. The calculated isentropic efficiency for the generator is eta(sub sg) = 84 percent at an enthalpy extraction ratio, eta(sub Ng) = 0.63. The calculated isentropic efficiency for the accelerator is eta(sub sa) = 81 percent at an enthalpy addition ratio, eta(sub Na) = 0.62. An assessment of the ionization fraction necessary to achieve a conductivity of sigma = 1.0 mho/m is n(sub e)/n = 1.90 X 10(exp -6), and for sigma = 5.0 mho/m is n(sub e)/n = 9.52 X 10(exp -6).

  16. The vessel fluence; Fluence cuve

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This book presents the proceedings of the technical meeting on the reactors vessels fluence. They are grouped in eight sessions: the industrial context and the stakes of the vessels control; the organization and the methodology for the fluence computation; the concerned physical properties; the reference computation methods; the fluence monitoring in an industrial context; vessels monitoring under irradiation; others methods in the world; the research and development programs. (A.L.B.)

  17. Blood vessel rupture by cavitation

    OpenAIRE

    Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.; Matula, Thomas J.

    2010-01-01

    Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion ca...

  18. Reactor pressure vessel cooling device

    International Nuclear Information System (INIS)

    A spray pipeline for the head of a pressure vessel is connected to a spray for the pressure vessel head of the reactor pressure vessel. The pipeline is equipped with a spray flow rate control valve for controlling the flow rate of spray jetted from the head spray to the inside of the reactor and a thermometer for spray water. A reactor pressure vessel cooling and controlling portion intakes temperature signals sent from a thermometer for the head of the pressure vessel, a thermometer for the flange of the pressure vessel and a thermometer for the body of the pressure vessel, and a thermometer for spray water. Then, it outputs restriction signal for the opening degree of the spray flow rate control valve to restrict the spray water flow rate within an appropriate range when the difference between the temperature of each portion of the pressure vessel and the temperature of spray water is increased to greater than an allowable temperature difference. With such procedures, spray operation for the head of the pressure vessel can be conducted not only upon emergency but also during reactor cooling operation. (I.N.)

  19. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  20. Americium behaviour in plastic vessels

    International Nuclear Information System (INIS)

    The adsorption of 241Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of 241Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of 241Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  1. Refinements to pressure vessel steel embrittlement correlations

    International Nuclear Information System (INIS)

    ASTM E 900-87, Standard Guide for Predicting Neutron Radiation Damage to Reactor Vessel Materials, provides methods for predicting the effects of fast neutron irradiation on the toughness of reactor pressure vessel materials. The prediction methodology is similar but separate for the steel base metal and weld metal. The methodology relies on a correlation between the chemical content of the steel and the fast neutron fluence. The prediction methodology is used to assess the margin of safety against fracture of the reactor vessel during normal operation and postulated transients. The purpose of this paper is to describe the results of an effort to improve the accuracy of the predictions of transition temperature shift. Numerous issues have been identified which could influence the calculational approach. This evaluation was performed using a scrubbed data base of reactor vessel surveillance data coupled with best-estimate irradiation temperatures; the latter were based on the reactor vessel cold leg temperatures rather than the go/no go thermal monitor data. A term for dependence on irradiation temperature was derived and added to the correlation for irradiation induced shift of the transition temperature. The ultimate objective is to contribute to the development of an improved understanding of the empirical relationships which, when coupled with theoretical models of irradiation damage mechanisms, will result in more accurate correlations for inclusion in ASTM E 900. The data base improvements, addition of a temperature term, consideration of saturation effects (with neutron fluence or copper content) and separation by material subsets are intended to assure that the best estimate predictions and their uncertainty are as realistic as possible

  2. Endothelium-dependent relaxation of blood vessels

    International Nuclear Information System (INIS)

    Dilation of blood vessels in response to a large number of agents has been shown to be dependent on an intact vascular endothelium. The present studies examine some aspects of endothelium-dependent vasodilation in blood vessels of the rabbit and rat. Using the rabbit ear artery and the subtype-selective muscarinic antagonist pirenzepine, muscarinic receptors of the endothelium and smooth muscle cells were shown to be of the low affinity M2 subtype. Inhibition of [3H](-)quinuclidinyl benzilate was used to determine affinity for the smooth muscle receptors while antagonism of methacholine induced vasodilation yielded the endothelial cell receptor affinity. The effect of increasing age (1-27 months) on endothelium-dependent relaxation was studied in aortic rings, perfused tail artery and perfused mesenteric bed of the Fisher 344 rat. The influence of endothelium on contractile responses was examined using the perfused caudal artery

  3. Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Siminelakis Stavros N

    2010-01-01

    Full Text Available Abstract During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB, hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved.

  4. Minimally invasive coronary artery bypass grafting: initial Connecticut experience.

    Science.gov (United States)

    Tellides, G; Maragh, M R; Smith, J M; Kopf, G S; Ezekowitz, M; Remetz, M; Elefteriades, J A

    1997-03-01

    We report the initial Connecticut experience with minimally invasive coronary artery bypass grafting. This procedure allows bypass grafting to the left anterior descending coronary artery utilizing the internal mammary artery as the conduit. The procedure is minimally invasive because it is performed through a mini-thoracotomy incision in the fourth anterior intercostal space and it is conducted without the use of cardiopulmonary bypass. The procedure has been applied to 13 patients operated between February and October 1996. All but one patient selected were poor candidates for conventional coronary artery bypass surgery because of advanced age (6), chronic renal failure/dialysis/kidney transplant (4), redo status with vulnerable grafts (1), severe peripheral vascular disease (6), severe chronic obstructive pulmonary disease (4). All patients survived operation and were discharged in good condition. Mean postoperative intubation time was seven hours and mean hospital stay was 4.5 days despite the very high pre-existing comorbidity of these patients. All patients are alive at the current follow-up time. Two patients required a conventional bypass procedure for occlusion of the minimally invasive graft, the first because of diffuse disease in the target artery and the second attributable to the technical limitations of minimally invasive coronary artery bypass grafting; both tolerated the subsequent procedure well. All patients are now angina-free. All four grafts studied by routine postoperative angiography were widely patent. Routine post-operative exercise nuclear imaging was normal in an additional patient. This procedure of minimally invasive coronary artery bypass grafting offers significant advantages compared to the conventional bypass procedure (short hospital stay, quick recovery, and, especially, avoidance of cerebrovascular accidents caused by the heart-lung machine). This minimally invasive procedure is expected to apply to a growing percentage of

  5. Infiltration and Bypass Flow of Cracking Puddled Soils

    Directory of Open Access Journals (Sweden)

    M.J. Islam

    2004-01-01

    Full Text Available A study of infiltration and bypass flow was conducted in a wet soil bin with three different soils treatments (sandy loam, clay loam and clay soil to determine the swelling behaviour of cracking puddled soils by watering and its impact on bypass flow. Infiltration rate for the soils was recorded after puddling the soils. Then the puddled soils were allowed to dry for a period of up to 15 days. After that the plots were rewetted in order to observe the swelling and bypass behaviour of cracked soils. From this study it is observed that the infiltration rates of puddled soils were very low (0.03-0.05 mm h-1 mainly due to the puddling effect. The study indicates that cracks on puddled soils at 15th day�s of drying are effectively irreversible. The maximum bypass flow was recorded for the clay loam soil. During the first day, the flow rate was extremely high at 313 mm h-1. But this higher rate gradually reduced from the second day and onwards. The bypass flow rate for the clay loam and clay soil was almost same. The study reveals that it is not possible to swell up shrinkage cracks on puddled soils by watering alone. Re-working of the soil is necessary to seal the cracks.

  6. Photovoltaic-module bypass-diode encapsulation. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    1983-06-20

    The design and processing techniques necessary to incorporate bypass diodes within the module encapsulant are presented in this annual report. A comprehensive survey of available pad-mounted PN junction and Schottky diodes led to the selection of Semicon PN junction diode cells for this application. Diode junction-to-heat spreader thermal resistance measurements, performed on a variety of mounted diode chip types and sizes, have yielded values which are consistently below 1/sup 0/C per watt, but show some instability when thermally cycled over the temperature range from -40 to 150/sup 0/C. Based on the results of a detailed thermal analysis, which covered the range of bypass currents from 2 to 20 amperes, three representative experimental modules, each incorporating integral bypass diode/heat spreader assemblies of various sizes, were designed and fabricated. Thermal testing of these modules has enabled the formation of a recommended heat spreader plate sizing relationship. The production cost of three encapsulated bypass diode/heat spreader assemblies were compared with similarly rated externally-mounted packaged diodes. An assessment of bypass diode reliability, which relies heavily on rectifying diode failure rate data, leads to the general conclusion that, when proper designed and installed, these devices will improve the overall reliability of a terrestrial array over a 20 year design lifetime.

  7. Modeling of a confinement bypass accident with CONSEN, a fast-running code for safety analyses in fusion reactors

    International Nuclear Information System (INIS)

    Highlights: • The CONSEN code for thermal-hydraulic transients in fusion plants is introduced. • A magnet induced confinement bypass accident in ITER has been simulated. • A comparison with previous MELCOR results for the accident is presented. -- Abstract: The CONSEN (CONServation of ENergy) code is a fast running code to simulate thermal-hydraulic transients, specifically developed for fusion reactors. In order to demonstrate CONSEN capabilities, the paper deals with the accident analysis of the magnet induced confinement bypass for ITER design 1996. During a plasma pulse, a poloidal field magnet experiences an over-voltage condition or an electrical insulation fault that results in two intense electrical arcs. It is assumed that this event produces two one square meters ruptures, resulting in a pathway that connects the interior of the vacuum vessel to the cryostat air space room. The rupture results also in a break of a single cooling channel within the wall of the vacuum vessel and a breach of the magnet cooling line, causing the blow down of a steam/water mixture in the vacuum vessel and in the cryostat and the release of 4 K helium into the cryostat. In the meantime, all the magnet coils are discharged through the magnet protection system actuation. This postulated event creates the simultaneous failure of two radioactive confinement barrier and it envelopes all type of smaller LOCAs into the cryostat. Ice formation on the cryogenic walls is also involved. The accident has been simulated with the CONSEN code up to 32 h. The accident evolution and the phenomena involved are discussed in the paper and the results are compared with available results obtained using the MELCOR code

  8. Modeling Of Blood Vessel Constriction In 2-D Case Using Molecular Dynamics Method

    CERN Document Server

    Rendi, Mohamad; Viridi, Sparisoma

    2013-01-01

    Blood vessel constriction is simulated with particle-based method using a molecular dynamics authoring software known as Molecular Workbench (WM). Blood flow and vessel wall, the only components considered in constructing a blood vessel, are all represented in particle form with interaction potentials: Lennard-Jones potential, push-pull spring potential, and bending spring potential. Influence of medium or blood plasma is accommodated in plasma viscosity through Stokes drag force. It has been observed that pressure p is increased as constriction c is increased. Leakage of blood vessel starts at 80 % constriction, which shows existence of maximum pressure that can be overcome by vessel wall.

  9. Histomorphological changes of vessel structure in head and neck vessels following preoperative or postoperative radiotherapy

    International Nuclear Information System (INIS)

    Patients and Methods: In 348 patients (October 1995-March 2002) receiving primarly or secondarily 356 microvascular hard- and soft tissue reconstruction, a total of 209 vessels were obtained from neck recipient vessels and transplant vessels during anastomosis. Three groups were analysed: group 1 (27 patients) treated with no radiotherapy or chemotherapy; group 2 (29 patients) treated with preoperative irradiation (40-50 Gy) and chemotherapy (800 mg/m2/day 5-FU and 20 mg/m2/day cisplatin) 1.5 months prior to surgery; group 3 (20 patients) treated with radiotherapy (60-70 Gy) (median interval 78.7 months; IQR: 31.3 months) prior to surgery. From each of the 209 vessel specimens, 3 sections were investigated histomorphometrically, qualitatively and quantitatively (ratio media area/total vessel area) by NIH-Image-digitized measurements. To evaluate these changes as a function of age, radiation dose and chemotherapy, a statistical analysis was performed using an analysis of covariance and χ2 tests (p > 0.05, SPSS V10). Results: In group 3, qualitative changes (intima dehiscence, hyalinosis) were found in recipient arteries significantly more frequently than in groups 1 and 2. For group 3 recipient arteries, histomorphometry revealed a significant decrease in the ratio media area/total vessel area (median 0.51, IQR 0.10) in comparison with groups 1 (p = 0.02) (median 0.61, IQR 0.29) and 2 (p = 0.046) (median 0.58, IQR 0.19). No significant difference was found between the vessels of groups 1 and 2 (p = 0.48). There were no significant differences in transplant arteries and recipient or transplant veins between the groups. Age and chemotherapy did not appear to have a significant influence on vessel changes in this study (p > 0.05). Conclusions: Following irradiation with 60-70 Gy, significant qualitative and quantitative histological changes to the recipient arteries, but not to the recipient veins, could be observed. In contrast, irradiation at a dose of 40-50 Gy and

  10. 血糖水平对急性脑血管病患者神经功能恢复的影响%The influence of blood sugar level on the recovery of patients' nerve function of acute cerebral vessel disease

    Institute of Scientific and Technical Information of China (English)

    郝淑梅; 石寄平; 谢艳萍

    2001-01-01

    @@ Background:Diabetes mellitus is one of risk factors leading to acute cerebral vessel disease(ACVD),and people have paid more attention to the fact that increase of blood sugar level after ACVD can aggravate nerve system impairment. Objective:To study the influence of blood sugar level increase on the recovery of nerve function of ACVD. Design:To make retrospective analysis on the relationship between prognosis and ACVD blood sugar level increase,the 157 patients lived in our hospital between March 1995 and March 2001.

  11. Vessel with improved motion control

    NARCIS (Netherlands)

    Keuning, J.A.

    2014-01-01

    The invention concerns a vessel (1) having a planing surface (2) and a transom (3) at a stern of the vessel, mounted on the transom is an interceptor (4) and an actuator (7) to move the interceptor in vertical direction. In accordance with the invention the transom (3) defines a sharp edge with the

  12. Strain Growth in Containment Vessels

    Institute of Scientific and Technical Information of China (English)

    DONG Q; LI Q M; ZHENG J Y

    2006-01-01

    Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading.The elastic response of the vessel may become larger in a later stage compared to its response during the initial stage.The dynamic responses of infinitely long cylindrical containment vessels subjected to uniformly-distributed internal blast loading are studied using LS-DYNA.The development of bending modes and the interaction between the breathing mode and bending modes are observed.The methodology developed for dynamic elastic buckling analysis is employed to study the strain growth phenomenon in explosion containment vessels.It is shown that the dynamic instable vibration of a containment vessel is the basic mechanism of strain growth.

  13. Effects of perioperative statin treatment on postoperative atrial fibrillation and cardiac mortality in patients undergoing coronary artery bypass grafting: a propensity score analysis

    Directory of Open Access Journals (Sweden)

    Ayşegül Kunt

    2015-08-01

    Full Text Available Aim To evaluate the effect of perioperative statin treatment on postoperative atrial fibrillation and cardiac mortality in patients undergoing coronary artery bypass grafting. Methods A total of 1890 patients who underwent isolated coronary artery bypass were analyzed retrospectively, of which 425 patients (22.4% older than 70 were included in the study. The demographic properties, preoperative, operative and postoperative data and other medications of these patients were recorded. Continuous preoperative and postoperative atorvastatin therapy were received by 124 (29.17% patients; 301 (70.82% patients were matched to a control group (no-statin group. The two groups were matched by propensity score analysis in terms of atrial fibrillation development and cardiac mortality. Results Medical history, medical treatment, cardiovascular history, and operative characteristics demonstrated significant heterogeneity in both groups. Postoperative atrial fibrillation was similar in both groups. Before propensity score matching, the percentages of patients in postoperative atrial fibrillation with respect to Atorvastain-group and No-statin-group were 13.71 and 10.3 respectively; however, those were 13.71 and 14.51 after matching. In a multivariate regression analysis, five-vessel bypass (odds ratio OR, 2.354; 95% confidence interval CI, 0.99 to 5.57 was an independent predictor of postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting. In-hospital mortality was higher in the Atorvastatin-group compared with the No-statingroup: 124 (8.9% versus 301 (3.7%, respectively; p=0.027. Conclusion Perioperative atorvastatin treatment is not found to be associated with reduced postoperative atrial fibrillation and cardiac mortality in patients undergoing isolated coronary artery bypass grafting above the age of seventy years.

  14. Adenosine Preconditioning versus Ischemic Preconditioning in Patients undergoing Off-Pump Coronary Artery Bypass (OPCAB

    Directory of Open Access Journals (Sweden)

    SeyedKhalil Forouzannia

    2015-10-01

    Full Text Available Background: During off-pump coronary artery bypass (OPCAB, the heart is subjected to ischemic and reperfusion injury. Preconditioning is a mechanism that permits the heart to tolerate myocardial ischemia. The aim of this study was to compare the effects of Adenosine preconditioning with ischemic preconditioning on the global ejection fraction (EF in patients undergoing OPCAB.Methods: In this single-blind, randomized controlled trial, sixty patients undergoing OPCAB were allocated into three equally-numbered groups through simple randomization: Adenosine group, ischemic group, and control group. The patients in the Adenosine group received an infusion of Adenosine. In the ischemic group, ischemic preconditioning was induced by the temporary occlusion of the left anterior descending coronary artery twice for a 2-minute period, followed by 3-minute reperfusion before bypass grafting of the first coronary vessel. The control group received an intravenous infusion of 0.9% saline. Blood samples at different times were sent for the measurement of creatine kinase isoenzyme MB (CK-MB and cardiac troponin I (cTnI. We also recorded electrocardiographic indices and clinical parameters, including postoperative use of inotropic drugs and preoperative and postoperative EF.Results: History of myocardial infarction, hyperlipidemia, diabetes mellitus, kidney disease, preoperative arrhythmias, and utilization of postoperative inotrope was the same between the three groups. The incidence of postoperative arrhythmias was not significant between the three groups. Also, there were no significant differences in preoperative and postoperative EF and the serum levels of enzymes (cTnI and CK-MB between the groups.Conclusion: Based on the findings of this study, there was no significant difference in the postoperative EF between the groups. Although the incidence of arrhythmias was higher in the ischemic preconditioning group than in the other groups, the difference

  15. Induced Remote Ischemic pre-conditioning on Ischemia - reperfusion Injury in patients undergoing coronary artery bypass

    International Nuclear Information System (INIS)

    To determine the role of remote ischemic pre-conditioning (riPC) on myocardium, against ischemia reperfusion injury in patients undergoing coronary artery bypass graft (CABG) surgery by measuring CKMB levels. Study Design: A randomized controlled trial. Place and Duration of Study: The Surgical Department of Armed Forces Institute of Cardiology/National Institute of Heart Diseases, Rawalpindi, from January to June 2008. Methodology: One hundred patients with double and triple vessels coronary artery disease were randomized in two groups of 50 each. riPC protocol consisted of 3 x 5 minutes of forearm ischemia, induced by a blood pressure cuff inflated to 200 mmHg, with an intervening 5 minutes of reperfusion, during which the cuff was deflated. Patients in the control group were not subjected to limb ischemia. The protocol of induced ischemia was completed before placing patients on extracorporeal bypass circuit. At the end of surgery serum CKMB levels were measured and compared at 8, 16, 24 and 48 hours from both the groups. Written informed consent was taken from patients. Study was approved by the hospital ethical committee. Results: Remote ischemic pre-conditioning significantly reduced CKMB levels at 8, 16, 24 and 48 hours after surgery with p-values of 0.026, 0.021, 0.052 and 0.003 respectively. There was mean reduction of 3 iu/l in CKMB levels, in patients who underwent riPC protocol prior to CABG surgery, compared to control group. Conclusion: This study showed a significant reduction of enzyme marker CKMB in patients subjected to riPC prior to CABG surgery. This suggests lesser degree of myocardial damage compared to control group in CABG patients. (author)

  16. Full turbine bypass system for nuclear power plant

    International Nuclear Information System (INIS)

    With the increase in the weight of electric power network, vigilant watch is kept on the toughness of nuclear power plants against disturbances on the side of the network. Basically speaking, it is desirable that reactors continue operation even in case the station is removed from the network due to an outside disturbance. In order to meet this requirement, the application of a full-load turbine bypass system for 1,100-MW-class nuclear power plants has been planned; the development of system components was advanced; the reliability of the full-load turbine bypass system was confirmed through simulation tests. The process of development is outlined here. (author)

  17. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H; Wiik, A; Schroeder, T V; Secher, N H

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... concentration of troponin I (n = 8). In conclusion, tissue injury was reflected by increases in muscle enzymes in plasma. We found an inverse correlation between lower leg electrical impedance and volume, but the deviation in electrical impedance was approximately twice that of the leg volume. Electrical...... impedance appears to be a useful method for the evaluation of lower leg oedema after distal bypass surgery....

  18. Surgical cartographic navigation system for endoscopic bypass grafting.

    Science.gov (United States)

    Voruganti, Arun; Mayoral, Rafael; Jacobs, Stephan; Grunert, Ronny; Moeckel, Hendrik; Korb, Werner

    2007-01-01

    Endoscopic bypass grafting with the da Vinci system is still challenging and needs high level of experience and skill of the surgeon. Therefore, it is necessary to support the surgeon with enhanced vision and augmented reality. The augmentation of the patient model into the view of the endoscope is a direct approach to enhance support. The results of a preclinical study are shown in this paper. The method applied is suitable for endoscopic bypass grafting and in general applicable to minimal invasive surgery. The system was designed as an open architecture to facilitate easy transfer of the methodology into other surgical domain applications. PMID:18002243

  19. Preliminary studies of coolant by-pass flows in a prismatic very high temperature reactor using computational fluid dynamics

    International Nuclear Information System (INIS)

    Three dimensional computational fluid dynamic (CFD) calculations for a 1/12 sector of a prismatic block through the core of a prismatic very high temperature gas-cooled reactor (VHTR) were conducted to investigate the influence of gap geometry on flow and temperature distributions in the reactor core using commercial CFD code FLUENT. Parametric calculations changing the gap width in a whole core length model of fuel and reflector columns were performed. The simulations show the effects of core by-pass flows in the heated core region by comparing results for several gap widths including zero gap width. The calculation results underline the importance of considering inter-column gap width for the evaluation of maximum fuel temperatures and temperature gradients in fuel blocks. It is shown that temperatures of core outlet flow from gaps and channels are strongly affected by the gap width of by-pass flow in the reactor core. (author)

  20. Preliminary studies of coolant by-pass flows in a prismatic very high temperature reactor using computational fluid dynamics

    International Nuclear Information System (INIS)

    Three dimensional computational fluid dynamic (CFD) calculations of a typical prismatic very high temperature gas-cooled reactor (VHTR) were conducted to investigate the influence of gap geometry on flow and temperature distributions in the reactor core using commercial CFD code FLUENT. Parametric calculations changing the gap width in a whole core length model of fuel and reflector columns were performed. The simulations show the effects of core by-pass flows in the heated core region by comparing results for several gap widths including zero gap width. The calculation results underline the importance of considering inter-column gap width for the evaluation of maximum fuel temperatures and temperature gradients in fuel blocks. In addition, it is shown that temperatures of core outlet flow from gaps and channels are strongly affected by the gap width of by-pass flow in the reactor core.

  1. Managing the Inflammatory Response after Cardiopulmonary Bypass : Review of the Studies in Animal Models

    NARCIS (Netherlands)

    Liguori, Gabriel Romero; Kanas, Alexandre Fligelman; Moreira, Luiz Felipe Pinho

    2014-01-01

    OBJECTIVE: To review studies performed in animal models that evaluated therapeutic interventions to inflammatory response and microcirculatory changes after cardiopulmonary bypass. METHODS: It was used the search strategy ("Cardiopulmonary Bypass" (MeSH)) and ("Microcirculation" (MeSH) or "Inflammat

  2. Natural headland sand bypassing; towards identifying and modelling the mechanisms and processes

    OpenAIRE

    Bin Ab Razak, M.S.

    2015-01-01

    Natural headland sand bypassing: Towards identifying and modelling the mechanisms and processes contributes to the understanding of the mechanisms and processes of sand bypassing in artificial and non-artificial coastal environments through a numerical modelling study. Sand bypassing processes in general are a relevant but poorly understood topic. This study attempts to link the theory and physics of sand bypassing processes which is significantly important in definition of coastal sedimentar...

  3. Serotonin, atherosclerosis, and collateral vessel spasm

    Science.gov (United States)

    Hollenberg, N.

    1988-01-01

    Studies on animal models demonstrate that platelet products contribute to vascular spasm in ischemic syndromes and that this is reversible with administration of ketanserin and thromboxane synthesis inhibitors. Laboratory animals (dogs, rabbits, and rats) that had femoral artery ligations exhibited supersensitivity to serotonin within days in their collateral blood vessels. This supersensitivity lasted at least 6 months. The response to serotonin was reversed by ketanserin, but not by 5HT-1 antagonists. Supersensitivity does not extend to norepinephrine, and alpha blockers do not influence the response to serotonin. It appears that platelet activation by endothelial injury contributes to ischemia through blood vessel occlusion and vascular spasm. When platelet activation occurs in vivo, blood vessel occlusion and vascular spasm are reversible in part by using ketanserin or agents that block thromboxane synthesis or its action. Combining both classes of agents reverses spasm completely. These findings support existing evidence that platelet products contribute to vascular disease, and provide an approach to improved management with currently available pharmacologic agents.

  4. Complete blood count and retinal vessel calibers.

    Directory of Open Access Journals (Sweden)

    Gerald Liew

    Full Text Available OBJECTIVE: The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. METHODS: Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992-4. Retinal arteriolar and venular calibers were measured from digitized retinal photographs using a validated semi-automated computer program. RESULTS: All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar caliber (p = 0.02, 0.03 and 0.001 respectively, while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular caliber (p<0.0001 for all. Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1-2 µm wider venular caliber. CONCLUSIONS: These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.

  5. 2D Fast Vessel Visualization Using a Vessel Wall Mask Guiding Fine Vessel Detection

    Directory of Open Access Journals (Sweden)

    Sotirios Raptis

    2010-01-01

    and then try to approach the ridges and branches of the vasculature's using fine detection. Fine vessel screening looks into local structural inconsistencies in vessels properties, into noise, or into not expected intensity variations observed inside pre-known vessel-body areas. The vessels are first modelled sufficiently but not precisely by their walls with a tubular model-structure that is the result of an initial segmentation. This provides a chart of likely Vessel Wall Pixels (VWPs yielding a form of a likelihood vessel map mainly based on gradient filter's intensity and spatial arrangement parameters (e.g., linear consistency. Specific vessel parameters (centerline, width, location, fall-away rate, main orientation are post-computed by convolving the image with a set of pre-tuned spatial filters called Matched Filters (MFs. These are easily computed as Gaussian-like 2D forms that use a limited range sub-optimal parameters adjusted to the dominant vessel characteristics obtained by Spatial Grey Level Difference statistics limiting the range of search into vessel widths of 16, 32, and 64 pixels. Sparse pixels are effectively eliminated by applying a limited range Hough Transform (HT or region growing. Major benefits are limiting the range of parameters, reducing the search-space for post-convolution to only masked regions, representing almost 2% of the 2D volume, good speed versus accuracy/time trade-off. Results show the potentials of our approach in terms of time for detection ROC analysis and accuracy of vessel pixel (VP detection.

  6. Multilayer Composite Pressure Vessels

    Science.gov (United States)

    DeLay, Tom

    2005-01-01

    A method has been devised to enable the fabrication of lightweight pressure vessels from multilayer composite materials. This method is related to, but not the same as, the method described in gMaking a Metal- Lined Composite-Overwrapped Pressure Vessel h (MFS-31814), NASA Tech Briefs, Vol. 29, No. 3 (March 2005), page 59. The method is flexible in that it poses no major impediment to changes in tank design and is applicable to a wide range of tank sizes. The figure depicts a finished tank fabricated by this method, showing layers added at various stages of the fabrication process. In the first step of the process, a mandrel that defines the size and shape of the interior of the tank is machined from a polyurethane foam or other suitable lightweight tooling material. The mandrel is outfitted with metallic end fittings on a shaft. Each end fitting includes an outer flange that has a small step to accommodate a thin layer of graphite/epoxy or other suitable composite material. The outer surface of the mandrel (but not the fittings) is covered with a suitable release material. The composite material is filament- wound so as to cover the entire surface of the mandrel from the step on one end fitting to the step on the other end fitting. The composite material is then cured in place. The entire workpiece is cut in half in a plane perpendicular to the axis of symmetry at its mid-length point, yielding two composite-material half shells, each containing half of the foam mandrel. The halves of the mandrel are removed from within the composite shells, then the shells are reassembled and bonded together with a belly band of cured composite material. The resulting composite shell becomes a mandrel for the subsequent steps of the fabrication process and remains inside the final tank. The outer surface of the composite shell is covered with a layer of material designed to be impermeable by the pressurized fluid to be contained in the tank. A second step on the outer flange of

  7. 21 CFR 870.4370 - Roller-type cardiopulmonary bypass blood pump.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Roller-type cardiopulmonary bypass blood pump. 870... Roller-type cardiopulmonary bypass blood pump. (a) Identification. A roller-type cardiopulmonary bypass blood pump is a device that uses a revolving roller mechanism to pump the blood through...

  8. 21 CFR 870.4360 - Nonroller-type cardiopulmonary bypass blood pump.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonroller-type cardiopulmonary bypass blood pump... Nonroller-type cardiopulmonary bypass blood pump. (a) Identification. A nonroller-type cardiopulmonary bypass blood pump is a device that uses a method other than revolving rollers to pump the blood...

  9. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  10. 21 CFR 870.4260 - Cardiopulmonary bypass arterial line blood filter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass arterial line blood filter... Cardiopulmonary bypass arterial line blood filter. (a) Identification. A cardiopulmonary bypass arterial line blood filter is a device used as part of a gas exchange (oxygenator) system to filter...

  11. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  12. Grounding Damage to Conventional Vessels

    DEFF Research Database (Denmark)

    Lützen, Marie; Simonsen, Bo Cerup

    2003-01-01

    The present paper is concerned with rational design of conventional vessels with regard to bottom damage generated in grounding accidents. The aim of the work described here is to improve the design basis, primarily through analysis of new statistical data for grounding damage. The current...... relation between the amount of deformed structure and the energy absorption. Finally, the paper shows how damage statistics for existing, conventional vessels can be used together with theoretical prediction methods for determining grounding damage distributions for new vessel types not included in the...

  13. Comprehensive assessment of a post-coronary bypass graft patient with cardiovascular magnetic resonance imaging and multi-detector computed tomography

    Institute of Scientific and Technical Information of China (English)

    Pairoj Rerkpattanapipat; Patcharee Paijitprapaporn; Suthipong Jongjirasiri; Jiraporn Laothamatas; Nithi Mahanonda

    2007-01-01

    Coronary bypass graft surgery (CABG) is a revascularization procedure which reduces myocardial ischemia and cardiovascular morbidity and mortality in selected patients; however, up to 40% of saphanous vein grafts may degenerate over 10 years. Although coronary angiography is the gold standard to detect graft patency and native vessel disease, sometimes it is difficult to locate the grafts resulting in increased exposure to radiation and contrast administration. This case highlights the utility of cardiac computerized tomography and magnetic resonance imaging to provide comprehensive noninvasive assessment in a patient post CABG.

  14. Numerical modelling of bypass transition in turbine cascades

    Czech Academy of Sciences Publication Activity Database

    Louda, P.; Příhoda, Jaromír; Kozel, K.

    Budapest: Budapest University of Technology and Economics, 2015. [International Conference on Fluid Flow Technologies /16./. Budapest (HU), 01.09.2015-04.09.2015] R&D Projects: GA ČR GAP101/12/1271 Institutional support: RVO:61388998 Keywords : 3D turbine cascade * bypass transition model * EARSM turbulence model Subject RIV: BK - Fluid Dynamics

  15. Emergency bypass post percutaneous atrial ablation: a case report.

    LENUS (Irish Health Repository)

    Hargrove, M

    2010-11-01

    A 34-year-old male undergoing percutaneous atrial ablation procedure for paroxysmal fibrillation required emergency sternotomy for cardiac tamponade. The patient had been anticoagulated and had received plavix and aspirin prior to and during the ablation procedure. Seven units of red cell concentrate had been transfused in the cardiac catherisation laboratory. On arrival in theatre, the patient was hypotensive, but was awake on induction of anaesthesia. No recordable blood pressure with non-invasive monitoring was observed. A sternotomy was immediately performed and, on evacuation of the pericardium, a bleeding site was not visible. The patient was commenced on cardiopulmonary bypass. Bleeding site was identified and the defect closed. The patient was weaned from cardiopulmonary bypass with minimal inotropic support and made an uneventful recovery. Bypass time was 38 minutes. A literature review showed a 1% incidence of post-ablation bleeding(1). The incidence of reverting to bypass for such an event has not been reported previously. During these procedures, it might be wise to have the cardiothoracic team notified while atrial ablation procedures are being performed in the cardiac catheterization laboratory.

  16. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... doing robotic gastric bypasses, we would do a hybrid. We would do part of it laparoscopically and ... if they’re using the robot, it’s a hybrid procedure. But now we’re doing them fully ...

  17. Advances in Weight Loss Surgery: The Fully Robotic Gastric Bypass

    Medline Plus

    Full Text Available ... that we see are those patients that have diabetes mellitus type II, and that’s diabetes associated with obesity. And there’s no question that ... The other question is, “Does gastric bypass eliminate diabetes and does the sleeve?” It’s not the type of -- it’s not actually the type of procedure ...

  18. Cycling firing method for bypass operation of bridge converters

    Science.gov (United States)

    Zabar, Zivan

    1982-01-01

    The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.

  19. Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.; Wohlgemuth, J.; Kurtz, S.

    2013-05-01

    This paper presents the result of high-temperature durability and thermal cycling testing and analysis for the selected diodes to study the detail of the thermal design and relative long-term reliability of the bypass diodes used to limit the detrimental effects of module hot-spot susceptibility.

  20. A device for a noninvasive evaluation of coronary bypass grafts.

    Science.gov (United States)

    McInerney, J J; Lamser, D G; Herr, M D

    1994-01-01

    A new device is presented for evaluating the patency of coronary bypass grafts. Bypass grafts are located within the chest cavity using a Compton backscatter imaging (CBI) technique that creates frontal plane tomographic images. The tomographic image pixels are mapped into computer memory and displayed. A display pointer is used to mark the position of the bypass graft. The computer uses that information to subsequently position a radiation detector, such that it "looks" at the location of the bypass graft within the closed chest. The patency of the graft is then evaluated by monitoring an X-ray induced iodine fluorescence transient in the graft, subsequent to a peripheral intravenous contrast injection. This imaging and graft evaluation device is relatively inexpensive and its application does not require cutdowns or catheterization. The associated radiation dose is 1/10 to 1/50 of that associated with alternative X-ray graft patency evaluation techniques. Preliminary testing has been performed on mechanical and animal models. PMID:18218544

  1. Integral bypass diodes in an amorphous silicon alloy photovoltaic module

    Science.gov (United States)

    Hanak, J. J.; Flaisher, H.

    1991-01-01

    Thin-film, tandem-junction, amorphous silicon (a-Si) photovoltaic modules were constructed in which a part of the a-Si alloy cell material is used to form bypass protection diodes. This integral design circumvents the need for incorporating external, conventional diodes, thus simplifying the manufacturing process and reducing module weight.

  2. Pathophysiology and treatment of edema following femoropopliteal bypass surgery

    NARCIS (Netherlands)

    te Slaa, A.; Dolmans, D. E. J. G. J.; Ho, G. H.; Moll, F. L.; van der Laan, L.

    2012-01-01

    Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this e

  3. Clinical benefit of steroid use in patients undergoing cardiopulmonary bypass

    DEFF Research Database (Denmark)

    Whitlock, Richard P; Chan, Simon; Devereaux, P J;

    2008-01-01

    We sought to establish the efficacy and safety of prophylactic steroids in adult patients undergoing cardiopulmonary bypass (CPB). We performed a meta-analysis of randomized trials reporting the effects of prophylactic steroids on clinical outcomes after CPB. Outcomes examined were mortality, myo...

  4. Turbulent spots detection during boundary layer by-pass transition

    Czech Academy of Sciences Publication Activity Database

    Jonáš, Pavel; Elsner, W.; Mazur, Oton; Uruba, Václav; Wysocki, M.

    -, č. 80 (2009), s. 16-19. ISSN N R&D Projects: GA AV ČR(CZ) IAA200760614; GA MŠk MEB050810 Institutional research plan: CEZ:AV0Z20760514 Keywords : turbulent spot * boundary layer * by-pass transition * turbulent spot detection Subject RIV: BK - Fluid Dynamics

  5. Bypassing of a barrier by dissociated and superlattice dislocations

    DEFF Research Database (Denmark)

    Bhushan, Karihaloo

    1975-01-01

    Very simple procedures are used to calculate the upper and lower bounds for the applied stress required for the leading extended (superlattice) dislocation in a group of n coplanar screw dislocations of like sign with Burgers vector b to bypass a noncoplanar perfect screw dislocation with Burgers...... vector mb (m...

  6. A device for a noninvasive evaluation of coronary bypass grafts

    International Nuclear Information System (INIS)

    A new device is presented for evaluating the patency of coronary bypass grafts. Bypass grafts are located within the chest cavity using a Compton Backscatter Imaging (CBI) technique that creates frontal plane tomographic images. The tomographic image pixels are mapped into computer memory and displayed. A display pointer is used to mark the position of the bypass graft. The computer uses that information to subsequently position a radiation detector, such that it looks at the location of the bypass graft within the closed chest. The patency of the graft is then evaluated by monitoring an X-ray induced iodine fluorescence transient in the graft, subsequent to a peripheral intravenous contrast injection. This imaging and graft evaluation device is relatively inexpensive and its application does not require cutdowns or catheterization. The associated radiation dose is 1/10 to 1/50 of that associated with alternative X-ray graft patency evaluation techniques. Preliminary testing has been performed on mechanical and animal models

  7. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... PINNACLEHEALTH HARRISBURG HOSPITAL HARRISBURG, PA 00:00:08 JOHN PENNOCK, MD: Welcome this evening to PinnacleHealth Harrisburg ... artery bypass surgery operation. My name is Dr. John Pennock. I'm going to introduce you shortly ...

  8. 2013 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  9. 2013 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  10. Caribbean PR Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels fishing in Puerto Rico. The catch and effort data for the entire trip are...

  11. 2011 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  12. Coastal Discard Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data on the type and amount of marine resources that are discarded or interacted with by vessels that are selected to report to the Southeast...

  13. 2011 Tug Towing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  14. SC/OQ Vessel Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data tables holding information for the Surf Clam/Ocean Quahog vessel and dealer/processor logbooks (negative and positive), as well as individual tag information...

  15. 2011 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  16. 2013 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  17. Mechanoinduction of lymph vessel expansion

    OpenAIRE

    Planas-Paz, Lara; Strilić, Boris; Goedecke, Axel; Breier, Georg; Fässler, Reinhard; Lammert, Eckhard

    2011-01-01

    Manipulating fluid pressure in the developing lymphatic system demonstrates that lymphatic endothelial cells are responsive to cell stretching, such that increased pressure promotes integrin-dependent VEGFR3 signalling, cell proliferation, and hence vessel growth.

  18. 2011 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  19. Reoperations for occluded arterial bypasses in the lower limbs

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background We reviewed the outcomes of reoperations for 29 patients (30 limbs) who had undergone occluded arterial bypass in the lower limbs from May 1996 to September 2005. Methods The 30 lower limbs of the 29 patients with arteriosclerotic obstruction received 44 reoperations, including thrombectomy alone (group T, 27) and inflow or outflow reconstruction plus thrombectomy (group C, 17). Among the 17 operations in group C, 17.6% (3/17) were inflow reconstructions involving the axillary-femoral (1), aorta-iliac (1) and aorta-femoral (1) arteries, and 76.4% (13/17) outflow reconstructions involving the femoral-popliteal bypass-tibial (8), femoral-tibial (1), femoral-popliteal bypass-popliteal arteries below the knee (2), and the femoral-popliteal bypass-tibial-peroneal trunk (2). One patient (1 limb) underwent both inflow and outflow reconstructions with an iliac arterial stent and a graft-popliteal anastomosis patch. Polytetrafluoroethylene (PTFE) grafts were used in the inflow or outflow reconstructions abve the knee. Autovenous grafts or autovenously combined PTFE grafts were used in the outflow reconstructions below the knee. Results The percentages of Fontaine stage III and IV before primary operation and reoperation were 60% (18/30) and 86.7% (26/30), respectively (P0.05). Among 42 reoperations, 19 failed within 1 month in groups T (16) and C (3) (P0.05). The rate of limb salvage was 64.29% (18/28). Conclusions The percentages of Fontaine stage III and IV before reoperation may be much higher than those before primary operation. Thrombectomy plus inflow/outflow reconstruction creates patency better than thrombectomy alone for re-occluded bypass.

  20. Cerebral Lesions in Patients Undergoing Coronary Artery Bypass Grafting in Relation to Asymptomatic Carotid and Vertebral Artery Stenosis

    DEFF Research Database (Denmark)

    Wiberg, Sebastian; Schoos, Mikkel; Sillesen, Henrik; Thomsen, Carsten; Hassager, Christian; Steinbrüchel, Daniel; Schroeder, Torben; Clemmensen, Peter; Kelbæk, Henning

    2015-01-01

    OBJECTIVES: Carotid artery stenosis (CAS) and vertebral artery stenosis (VAS) are associated with cerebral infarction after coronary artery bypass graft surgery (CABG). It remains unclear whether this association is causal. We investigated the associations between neurologically asymptomatic CAS......-operative subclinical cerebral lesions. The associations between CAS/VAS post-operative cerebral lesions were investigated. RESULTS: Forty-six patients were included in the study. 13% had significant CAS and 11% had significant VAS. Thirty-five percent had new cerebral infarction postoperatively. We found a significant...... association between the presence of cerebral vessel stenosis and acute cerebral infarction (67% vs. 27%, p = 0.047). However none of the patients with stenosis had isolated cerebral lesions in the ipsilateral vascular territory. CONCLUSION: Asymptomatic CAS and VAS is common in CABG patients and is associated...

  1. Lymphatic vessel development: fluid flow and valve-forming cells.

    Science.gov (United States)

    Kume, Tsutomu

    2015-08-01

    Hemodynamic forces regulate many aspects of blood vessel disease and development, including susceptibility to atherosclerosis and remodeling of primary blood vessels into a mature vascular network. Vessels of the lymphatic circulatory system are also subjected to fluid flow-associated forces, but the molecular and cellular mechanisms by which these forces regulate the formation and maintenance of lymphatic vessels remain largely uncharacterized. This issue of the JCI includes two articles that begin to address how fluid flow influences lymphatic vessel development and function. Sweet et al. demonstrate that lymph flow is essential for the remodeling of primary lymphatic vessels, for ensuring the proper distribution of smooth muscle cells (SMCs), and for the development and maturation of lymphatic valves. Kazenwadel et al. show that flow-induced lymphatic valve development is initiated by the upregulation of GATA2, which has been linked to lymphedema in patients with Emberger syndrome. Together, these observations and future studies inspired by these results have potential to lead to the development of strategies for the treatment of lymphatic disorders. PMID:26214518

  2. Vesselness propagation: a fast interactive vessel segmentation method

    Science.gov (United States)

    Cai, Wenli; Dachille, Frank; Harris, Gordon J.; Yoshida, Hiroyuki

    2006-03-01

    With the rapid development of multi-detector computed tomography (MDCT), resulting in increasing temporal and spatial resolution of data sets, clinical use of computed tomographic angiography (CTA) is rapidly increasing. Analysis of vascular structures is much needed in CTA images; however, the basis of the analysis, vessel segmentation, can still be a challenging problem. In this paper, we present a fast interactive method for CTA vessel segmentation, called vesselness propagation. This method is a two-step procedure, with a pre-processing step and an interactive step. During the pre-processing step, a vesselness volume is computed by application of a CTA transfer function followed by a multi-scale Hessian filtering. At the interactive stage, the propagation is controlled interactively in terms of the priority of the vesselness. This method was used successfully in many CTA applications such as the carotid artery, coronary artery, and peripheral arteries. It takes less than one minute for a user to segment the entire vascular structure. Thus, the proposed method provides an effective way of obtaining an overview of vascular structures.

  3. The value of semi-quantitative myocardial metabolic-perfusion scores in coronary artery bypasses grafting

    International Nuclear Information System (INIS)

    Objective: Coronary artery bypass grafting (CABG) is the preferred method of coronary revascularization in the coronary artery disease (CAD) patients with multi-vessel involvement. The study was aimed to evaluate the role of semi-quantitative assessment of myocardial viability scores using PET in CABG. Methods: Twenty-one consecutive patients with multi-vessel CAD were recruited from the department of cardiac/thoracic surgery. All patients underwent gated myocardial perfusion imaging (G-MPI) and 18F-fluorodeoxyglucose (FDG) myocardial PET imaging to assess the extent and severity of ischemia as well as the myocardial viability. The images were interpreted according to the semi-quantitative method issued by American Society of Nuclear Cardiology (ASNC) imaging guidelines using a 20-segment nomenclature. Summed rest score (SRS) and summed difference score (SDS) were calculated accordingly. All patients were scheduled for CABG within 2 weeks after the radionuclide myocardial imaging. The follow-up G-MPI was performed in all patients in the 3rd month after the surgery. Results: Out of the total 420 segments, 164 segments had abnormal myocardial perfusion by preoperative G-MPI. Among them, 93 segments were identified as non-viable (with difference score≥0) and the remaining 71 viable (with difference score <0). Based on their SDS, the patients were divided into 3 groups: group A (SDS≥0, n=5), group B (-5≤SDS<0, n8) and group C (SDS < -5, n=8). The mean change of global left ventricular ejection fraction (LVEF) after CABG in the three groups were -3.6%, 3.38% and 6.88% respectively. Conclusion: Assessment of myocardial viability by PET imaging is valuable in predicting whether the CAD patients may benefit from CABG. (authors)

  4. A novel methodology for adaptive wave filtering of marine vessels: Theory and experiments

    Digital Repository Service at National Institute of Oceanography (India)

    Hassani, V.; Pascoal, A.M.; Sorensen, A.J.

    This paper addresses a filtering problem that arises in the design of dynamic positioning systems for ships and offshore rigs subjected to the influence of sea waves. The vessel`s dynamic model adopted captures the sea state as an uncertain...

  5. Lymphatic vessels assessment in feline mammary tumours

    Directory of Open Access Journals (Sweden)

    Diracca Laura

    2007-01-01

    Full Text Available Abstract Background The lymphatic vessels play a crucial role in a variety of human cancers since tumour cell lymphatic invasion significantly influences prognosis. It is not known if pre-existing lymphatics are enough for tumour dissemination or de novo development is necessary. VEGFR-3 is an angiogenetic mediator for both lymphatic and blood vessels during embryonic development, and only for lymphatics after birth. VEGF is a mediator of both vasculogenesis and angiogenesis, regulates the growth of lymphatics in various experimental models, and is produced in many solid tumours. CD44 mediates hyaluronic acid (HA-dependent cell adhesion: besides promoting invasion, this interaction also supports neoangiogenesis that indirectly stimulates tumour cell proliferation. The expression of VEGF-C (Vascular Endothelial Growth Factor – C, its receptor VEGFR-3 and CD44, were studied on feline mammary samples to assess the importance of lymphangiogenesis and lymphangiotrophism in neoplasia. Methods Samples were taken from six normal mammary glands (NMG, ten benign (BT and 32 malignant (MT tumours. Immunohistochemical laminin/VEGFR-3 double stain, VEGF-C and CD44 stains were applied to 4 μm-thick sections, and their expression evaluated in intratumoral/extratumoral and intramammary/extramammary fields. Results All groups revealed a higher number of lymphatics in the extratumoral/extramammary areas. VEGF-C expression in the epithelium paralleled the number of positive vessels in the NMG, BT and MT, whereas VEGF-C higher expression was noted in the intratumoral fields only in infiltrating MT. CD44 score was lower in extratumoral than intratumoral fields in tumours and showed a significant increase in extramammary/extratumoral fields from NMG to MT. Pearson test showed a significant and inversely proportional correlation between CD44 expression and the number of lymphatic vessels with VEGFR-3 in malignant infiltrating tumours. Conclusion The number of both

  6. Local pressure testing of spherical vessels

    International Nuclear Information System (INIS)

    This work pertains to the numerical investigation of the feasibility of a proposed local pressure testing to verify structural integrity of nozzle-to-shell junctions in repaired/altered spherical pressure vessels. The “local pressure testing” involves the use of a small temporary testing closure at the nozzle-to-shell junction to get around the inconvenience of the conventional industry-wide pressure testing of the entire pressure vessel. However, it is essential in deciding on the reliability of such testing approach, to understand the influence of dimensional ratios between the nozzle, vessel and testing closure on achieving equivalent behavior, in terms of stresses and deformations, as compared to those associated with the full conventional testing. The paper presents the findings of a finite element study of the effect of cap size on the stresses near the junction of a cylindrical nozzle with a spherical vessel under internal pressure. The numerical model was verified by comparing its results to available analytical solutions of similar problems. The study focuses on the determination of the minimum required cap radius that will result in a local pressure testing that is equivalent to the conventional full pressure testing, mainly in terms of peak stresses at the junction. Results in the form of plots and empirical equations are presented for a parametric study covering a wide range of dimensions. The results show that the minimum required cap size is linearly related to the nozzle size, but also its value is usually much larger. This leads to the main conclusion that a reliable local pressure testing must use relatively large cap sizes, and that the caps with sizes slightly larger than those of the nozzle may not be acceptable. -- Highlights: • Local pressure testing of spherical vessels with nozzles is studied by the FEM. • It involves use of a “small” cylindrical cap wherein pressure testing is conducted. • It is established that the main

  7. The TPX vacuum vessel and in-vessel components

    International Nuclear Information System (INIS)

    The Tokamak Physics Experiment (TPX) is a superconducting tokamak with double-null diverters. TPX is designed for 1,000-second discharges with the capability of being upgraded to steady state operation. High neutron yields resulting from the long duration discharges require that special consideration be given to materials and maintainability. A unique feature of the TPX is the use of a low activation, titanium alloy vacuum vessel. Double-wall vessel construction is used since it offers an efficient solution for shielding, bakeout and cooling. Contained within the vacuum vessel are the passive coil system, Plasma Facing Components (PFCs), magnetic diagnostics, and the internal control coils. All PFCs utilize carbon-carbon composites for exposed surfaces

  8. 19 CFR 4.5 - Government vessels.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government...

  9. Long-term results after recanalization of acute and subacute thrombotic occlusions of the infra-aortic arteries and bypass-grafts using a rotational thrombectomy device

    International Nuclear Information System (INIS)

    Background: Evaluation of the acute and long-term results after recanalization of thrombotic occlusions of infra-aortic native arteries, stented arteries and bypass-grafts using a rotational thrombectomy device (8F Straub-RotarexTM). Materials and methods: From July 2000 to February 2002, in 98 patients (64% male, mean age 66±9 (range 47 to 90) years, mean duration of occlusion 31±33 (range 0 to 140) days, mean occlusion length 21±11 [range 2 to 40 ] cm) 100 vessel recanalizations were performed. 42% of the interventions were performed during the first 14 days after the onset of the symptoms (acute occlusions). These patients were classified according to the after the TASC protocol modified SVS/ISCVS-classification: Class I: n=22 (52%); class IIa: n=13 (32%); class IIb: n=6 (14%); class III: n=1 (2%). Subacute and chronic occlusions were classified according to Rutherford (58%): Stage 1: n=5 (9%); stage 2 and 3: n=39 (68%); stage 4: n=6 (10%); stage 5: n=8 (13%). Results: Primary success rate was 96% (ipsilateral interventions 99%; cross-over 40%). The restenosis rate after a mean follow-up of 13±4 months was 33% for native arteries (group 1), 74% for instent-recanalizations (group 2) and 86% for bypass-graft occlusions (group 3). 3% severe complications occurred: two amputations below the knee after unsuccessful recanalizations of a native artery and bypass-graft, respectively. One death because of multiorgan failure in patient who was already in cardiac shock before the successful intervention. Further 16 complications could be solved periinterventionally. The ancle-brachial index was significantly improved during follow-up (from 0.37±0.19 to 0.82±0.22 before discharge, 0.70±0.21 after 12 months, pTM device is useful in the treatment of acute and subacute thrombotic occlusions of infra-aortic arterial and bypass-graft occlusions, with promising long-term results in native vessels but unchanged high restenosis of stented arteries and bypass-grafts. (orig.)

  10. Indications for coronary artery bypass grafting in 2009: what is left to surgery.

    Science.gov (United States)

    Caparrelli, D J; Ghazoul, M; Diethrich, E B

    2009-02-01

    Coronary artery bypass grafting (CABG) remains the most common procedure performed by cardiac surgeons, yet it is clear that the landscape of coronary intervention is constantly changing as new technology is introduced and data from countless studies continues to be published. However, no single study will be able to clearly define the indications for surgical versus percutaneous revascularization in every clinical scenario given the complexity of this disease as well as that of the patients it afflicts. Moreover, the significant improvements in percutaneous therapy, medical therapy management, perioperative care and secondary prevention after revascularization have decreased the morbidity and mortality of coronary artery disease making comparison between therapies far more difficult. Based on the available literature to date, surgical revascularization (CABG) provides significant benefit in certain patient populations; particularly those with comorbid conditions (for example diabetes, left ventricular [LV] dysfunction) and with more severe disease (for example left main, three-vessel). The goal of this article is to outline the current for surgical revascularization (CABG) understanding that coronary artery disease will continue be an important cause of morbidity and mortality and further study and re-evaluation of these recommendations will likely be necessary as time goes on. PMID:19179987

  11. Lung cancer resection with concurrent off-pump coronary artery bypasses: safety and efficiency

    Science.gov (United States)

    Ma, Xuchen; Huang, Fangjiong; Zhang, Zhitai; Song, Feiqiang

    2016-01-01

    Background To assess the safety and efficacy of combined surgery for patients with concurrent lung cancer and severe coronary heart disease (CHD). Methods Between 2003 and 2014, 34 patients with stage I or II lung cancer and simultaneous severe CHD underwent combined off-pump coronary artery bypass (OPCAB) grafting and lung resection. Surgically, myocardial revascularization was performed first and followed by lobectomies through the same or a second incision. Video-assisted thoracoscopes were used in some cases. Five patients also received chemotherapy before or after combined surgery in an effort to improve the long-term survival. Results All patients survived the operation and no new myocardial infarctions (MIs) occurred in the perioperative period. The most frequent complications were cardiac arrhythmias (5 cases), atelectasis (4 cases), and pulmonary infections (2 cases). All patients were followed up for 5–60 months. Within this period, 6 patients (17.6%) died due to cancer recurrence. The 3- and 5-year survivals were 75% and 67% for these lung cancer patients, respectively. Conclusions Combined OPCAB and pulmonary resection for early stage lung cancer patients with concurrent severe CHD is a relatively safe and effective treatment with satisfactory long-term survival rates, especially for those patients with three-vessel disease who are not usually candidates for percutaneous coronary intervention (PCI) before open surgery.

  12. Testing device for large vessels

    International Nuclear Information System (INIS)

    For surveillance of the pressure vessel surface with respect to cracks or flaws e.g. an ultrasonic testing device is used. For this purpose it is necessary to move it across the entire surface. This is why there are provided in the interspace betweeen pressure vessel and shield vertical rails distributed across the circumference of the vessel. On them a carriage with the test equipment can be vertically guided over the surface of the pressure vessel. In addition the carriage for the test equipment has got an arm with which the equipment can be displaced between two neighbouring rails. With another carriage, which can pass around the vessel on a track above the upper ends of the vertical rails, it is possible to put the test equipment with its driving engine from one rail to another, using a rail extension part. The carriage to be moved along the horizontal path may be part of an entire train, the individual carriages of the train transporting special equipment e.g. for aligning the rail extension or the arm of the testing carriage. (DG)

  13. A stellarator helical vacuum vessel

    International Nuclear Information System (INIS)

    A design study of a stainless steel, heavy wall, helically shaped vacuum torus has been made for use in a proposed Stellarator configuration. The study concerns itself with the shape of the vacuum vessel and the division of the vessel into components that can be machined and welded together into a helical configuration. A complication in the design requires that a circular magnet coil be located at the minor toroidal axis and that this coil be embedded within the periphery of the vacuum vessel. The vacuum vessel has a minor toroidal axis diameter of 4 meters, a 68.6-cm shell diameter, and a 1.9-cm wall thickness. It twists about the minor toroidal axis twice in 3600. (An n value of 2). It is proposed that the unit be made of cylindrical segments with the ends of the cylinders cut at appropriate lengths and angles to form the helix. A mathematical derivation of the dimensions necessary to produce the required shapes of the segments has been made. Also, drawings of the vacuum vessel components have been produced on LANL's CTR CAD/CAM system. The procedure developed can be used for any value of n as dictated by physics requirements

  14. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    In a vacuum vessel of a thermonuclear device, a rib for connecting outer and inner walls and reinforcing them has an integrated structure of an H-like shaped cross section. The vacuum vessel is formed by an assembly of plural partial vacuum vessels. The partial vacuum vessels are disposed in plurality in the poloidal direction so as to make a wall thickness at a port greater than that of other portions and provide a wall of a substantially D-like shaped cross section in the poloidal direction. Then torus circumferential electric resistance of the vacuum vessels is decreased and electromagnetic force resistance is improved since the reinforcing ribs are present, thereby enabling to provide sufficient strength and rigidity relative to a large electromagnetic force generated by plasma disruption. In addition, since all the joining is conducted by butt welding such as by electron beam welding and laser beam welding, the number of working step is reduced, and the bead width is decreased to reduce deformation, thereby reducing length of welding lines and operation time, so that low welding strain method is enabled. Further, non-destructive test for the weld portion is enabled by using radiation ray or ultrasonic-flaw detection. (N.H.)

  15. Impact of Intraoperative Events on Cerebral Tissue Oximetry in Patients Undergoing Cardiopulmonary Bypass.

    Science.gov (United States)

    Ševerdija, Ervin E; Vranken, Nousjka P A; Teerenstra, Steven; Ganushchak, Yuri M; Weerwind, Patrick W

    2015-03-01

    Previous studies showed that decreased cerebral saturation during cardiac surgery is related to adverse postoperative outcome. Therefore, we investigated the influence of intraoperative events on cerebral tissue saturation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). A total of 52 adult patients who underwent cardiac surgery using pulsatile CPB were included in this prospective explorative study. Cerebral tissue oxygen saturation (SctO2) was measured in both the left and right cerebral hemisphere. Intraoperative events, involving interventions performed by anesthesiologist, surgeon, and clinical perfusionist, were documented. Simultaneously, in-line hemodynamic parameters (partial oxygen pressure, partial carbon dioxide pressure, hematocrit, arterial blood pressure, and CPB flow rates) were recorded. Cerebral tissue saturation was affected by anesthetic induction (p partial oxygen pressures changed. Cerebral tissue oximetry effectively identifies changes related to surgical events or vulnerable periods during cardiac surgery. Future studies are needed to identify methods of mitigating periods of reduced cerebral saturation. PMID:26390677

  16. Glycemic control and outcome related to cardiopulmonary bypass.

    Science.gov (United States)

    Thiessen, Steven; Vanhorebeek, Ilse; Van den Berghe, Greet

    2015-06-01

    Perioperative hyperglycemia, aggravated by cardiopulmonary bypass, is associated with adverse outcome in adult and pediatric patients. Whereas hyperglycemia was originally perceived as an adaptive response to surgical stress, it is now clear that glycemic control is a strategy to reduce adverse outcomes after cardiac surgery and cardiopulmonary bypass. The optimal blood glucose target, whether or not glycemic control should be initiated already intraoperatively, and whether or not perioperative glucose administration affects the impact of glycemic control on ischemia-reperfusion damage remain open questions. Hypoglycemia, the risk of which is increased with glycemic control, is also associated with adverse outcomes. However, it remains controversial whether brief episodes of hypoglycemia, rapidly corrected during glycemic control, have adverse effects on outcome. This review gives an overview of the currently available literature on glycemic control during and after cardiac surgery and focuses on the indicated open questions about this intervention for this specific patient population. PMID:26060029

  17. Arteriovenous fistulas aggravate the hemodynamic effect of vein bypass stenoses

    DEFF Research Database (Denmark)

    Nielsen, T G; Djurhuus, C; Pedersen, Erik Morre; Laustsen, J; Hasenkam, J M; Schroeder, Torben Veith

    1996-01-01

    PURPOSE: The purpose of this study was to assess the impact of arteriovenous fistulas combined with varying degrees of stenosis on distal bypass hemodynamics and Doppler spectral parameters. METHODS: In an in vitro flow model bypass stenoses causing 30%, 55%, and 70% diameter reduction were induced...... the systolic pressure drop from 31% to 48% and had significant impact on all waveform parameters. CONCLUSIONS: Distal arteriovenous fistulas enhance pressure loss across stenoses and affect downstream velocity waveform configuration. The presence of a combined fistula and a stenosis mimics the distal...... 10 cm upstream of a fistula with low outflow resistance. Flow and intraluminal pressure were measured proximal to the stenosis and downstream of the fistula. The waveform parameters peak systolic velocity, end-diastolic velocity, pulsatility index, and pulse rise time were determined from midstream...

  18. Analyses of 1/15 scale Creare bypass transient experiments

    International Nuclear Information System (INIS)

    RELAP4 analyses of several 1/15 scale Creare H-series bypass transient experiments have been done to investigate the effect of using different downcomer nodalizations, physical scales, slip models, and vapor fraction donoring methods. Most of the analyses were thermal equilibrium calculations performed with RELAP4/MOD5, but a few such calculations were done with RELAP4/MOD6 and RELAP4/MOD7, which contain improved slip models. In order to estimate the importance of nonequilibrium effects, additional analyses were performed with TRAC-PD2, RELAP5 and the nonequilibrium option of RELAP4/MOD7. The purpose of these studies was to determine whether results from Westinghouse's calculation of the Creare experiments, which were done with a UHI-modified version of SATAN, were sufficient to guarantee SATAN would be conservative with respect to ECC bypass in full-scale plant analyses

  19. Bilateral Internal Thoracic Artery Configuration for Coronary Artery Bypass Surgery

    Science.gov (United States)

    Boodhwani, Munir; Hanet, Claude; de Kerchove, Laurent; Navarra, Emiliano; Astarci, Parla; Noirhomme, Philippe; El Khoury, Gebrine

    2016-01-01

    Background— Bilateral internal thoracic arteries (BITA) have demonstrated superior patency and improved survival in patients undergoing coronary artery bypass grafting. However, the optimal configuration for BITA utilization and its effect on long-term outcome remains uncertain. Methods and Results— We randomly assigned 304 patients undergoing coronary artery bypass grafting using BITA to either in situ or Y grafting configurations. The primary end point was 3-year angiographic patency. Secondary end points included major adverse cardiac and cerebrovascular events (ie, death from any cause, stroke, myocardial infarction, or repeat revascularization) at 7 years. More coronary targets were able to be revascularized using internal thoracic arteries in patients randomized to Y grafting versus in situ group (3.2±0.8 versus 2.4±0.5 arteries/patient; PURL: http://www.clinicaltrials.gov. Unique identifier: NCT01666366. PMID:27406988

  20. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... than two-millimeter vessel. It looks like a good size vessel. The thing that's very nice about this procedure is that ... 00:32:01 JOHN PENNOCK, MD: It looks good. 00:32:16 CHRIS ... all the way across the proximal side obviously. Why don't you give me another ...

  1. Reactor vessel for pebble beds

    International Nuclear Information System (INIS)

    The wall and the bottom of the vessel for the gas-cooled pebble-bed reactor consist of numerous blocks of graphite or carbon rock piled up. They are held together by an exterior cylindrical or polygonal ring and supported by a foundation. The blocks form coherent sectors resp. annular sectors with well-defined separating lines. At high temperatures or load change operation these sectors behave like monolithic blocks expanding heely and contracting again, the center of the vessel remaining fixed. The forces causing the compression result from the own weight of the sectors and the weight of the pebble bed. This motion is supported by the convex arrangement of the opposite surfaces of the sectors and the supporting walls and by roller bearings. The bottom of the vessel may be designed funnel-shaped, in this way facilitating the removal of spheres. (DG)

  2. The German pressure vessel code

    International Nuclear Information System (INIS)

    The philosophy and the safety aspects of the German pressure vessel code is summarised. Emphasis is laid upon material selection, design, manufacture and inspection. The AD specifications, which are embedded in the German regulation for the prevention of accidents 'Pressure Vessels' are compiled primarily to give a measure of safety to the average plant. The possible types of failure are discussed in connection with design aspects. It is shown in detail how the AD specifications count for inelastic material behaviour. A comparison is also made between the German code and the ASME boiler and pressure vessel code. Comparatively, the allowable stresses due to the German code are higher, leading to thinner walls in many cases. This is compensated for by rigorous inspection and non-destructive testing during manufacture. Regular examinations round up the system of safety. It is concluded that the German code gives a high degree of safety and flexibility to the manufacturer. (author)

  3. Access pricing, bypass and universal service in post

    OpenAIRE

    Armstrong, Mark

    2006-01-01

    A postal regulator typically faces two issues which make the design of efficient access pricing especially difficult and which complicate the process of liberalizing the industry. First, universal service obligations, together with the presence of fixed costs, require retail prices to depart from the underlying marginal costs of the incumbent provider. Second, competing firms may be able to bypass the incumbent’s delivery network. Within a simple and stylized framework, this note ...

  4. Effects of Deep Breathing Exercises after Coronary Artery Bypass Surgery

    OpenAIRE

    Westerdahl, Elisabeth

    2004-01-01

    Deep breathing exercises are widely used in the postoperative care to prevent or reduce pulmonary complications, but no scientific evidence for the efficacy has been found after coronary artery bypass grafting (CABG) surgery. The aim of the thesis was to describe postoperative pulmonary function and to evaluate the efficacy of deep breathing exercises performed with or without a blow bottle device for positive expiratory pressure (PEP) 10 cmH2O or an inspiratory resistance-positive expirator...

  5. An Efficient Bypassing Void Routing Algorithm for Wireless Sensor Network

    OpenAIRE

    2015-01-01

    Since the sensor node’s distribution in a wireless sensor network (WSN) is irregular, geographic routing protocols using the greedy algorithm can cause local minima problem. This problem may fail due to routing voids and lead to failure of data transmission. Based on the virtual coordinate mapping, this paper proposes an efficient bypassing void routing protocol to solve the control packet overhead and transmission delay in routing void of WSN, which is called EBVRPVCM. The basic idea is to t...

  6. Constitutive modeling of coronary artery bypass graft with incorporated torsion

    Czech Academy of Sciences Publication Activity Database

    Horný, L.; Chlup, Hynek; Žitný, R.; Adámek, T.

    2009-01-01

    Roč. 49, č. 2 (2009), s. 273-277. ISSN 0543-5846 R&D Projects: GA ČR(CZ) GA106/08/0557 Institutional research plan: CEZ:AV0Z20760514 Keywords : coronary artery bypass graft * constitutive model * digital image correlation Subject RIV: BJ - Thermodynamics Impact factor: 0.439, year: 2009 http:// web .tuke.sk/sjf-kamam/mmams2009/contents.pdf

  7. Coronary Artery Bypass Surgery - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Chinese - Simplified (简体中文) Chinese - Traditional (繁體中文) French (français) Hindi (हिन्दी) Japanese (日本語) Korean (한국어) Russian (Русский) ... coronarien - français (French) Bilingual PDF Health Information Translations Hindi (हिन्दी) Coronary Artery Bypass Surgery हिन्दी ( ...

  8. CULTURAL DIAGNOSIS AND BYPASSING; THE EFFECT ON SUCCESSFUL INTERNATIONALIZATION

    OpenAIRE

    Andrews Adugudaa Akolaa

    2012-01-01

    Globalization and its effect on business continue to propel firms to look beyond local markets for opportunities for market development and as a source of growth. However, Cultural differences in various markets continue to exert enormous pressure on international market operations as a result of cultural bypassing or misdiagnosis and this requires international marketers to undertake robust cultural analysis to ensure successful market servicing strategies. This paper reviews and discusses t...

  9. Adherence to treatment after coronary bypass surgery: Psychological aspects

    OpenAIRE

    Maria V. Iakovleva

    2016-01-01

    Poor adherence to treatment is a problem of great importance and striking magnitude. Its consequences are increased health care costs and poor health outcomes. It defined the objective of this research, which is the study of psychological characteristics of patients with different degrees of adherence to rehabilitation treatment after coronary bypass surgery. Ninety male and female patients with CHD, aged 46---71, were examined. The study was carried out using the questionnaire of wa...

  10. Successful cardiopulmonary bypass in diabetics with anaphylactoid reactions to protamine.

    OpenAIRE

    Walker, W. S.; Reid, K G; Hider, C F; Davidson, I. A.; Boulton, F. E.; Yap, P L

    1984-01-01

    Two insulin dependent diabetics with previous anaphylactic like (anaphylactoid) reactions to protamine underwent successful cardiopulmonary bypass for coronary artery surgery. Platelet concentrates instead of protamine were used to neutralise their systemic heparinisation. In both cases the anaphylactoid reactions first became apparent after administration of protamine sulphate at the end of cardiac catheterisation. These cases show that adverse reactions to protamine need not be a contraindi...

  11. Immunocytochemical features of obstructed saphenous vein coronary artery bypass grafts.

    OpenAIRE

    Brody, J I; Pickering, N J; Fink, G B

    1989-01-01

    The peroxidase-immunoperoxidase immunocytochemical method was used on 27 saphenous vein coronary artery bypass grafts, which had been resected because of recurrent angina, to identify in situ cellular and humoral elements possibly associated with graft occlusion. Immunostaining was performed on paraffin wax embedded control saphenous vein and graft sections incubated directly with primary antibodies against von Willebrand antigen (vWFAg), fibronectin, fibrinogen, leucocyte common antigen (LCA...

  12. A review of 155 extra-anatomic bypass grafts.

    OpenAIRE

    Foster, M.C.; Mikulin, T; Hopkinson, B R; Makin, G. S.

    1986-01-01

    Extra-anatomic bypass grafting has been used as treatment for patients with aorto-iliac disease who were considered unfit for aortic surgery. Eighty five percent of the patients had ischaemic pain at rest or skin necrosis. One hundred and three femorofemoral (FF) grafts, 40 axillounifemoral and 12 axillobifemoral grafts were performed. Femoropopliteal extension grafts were performed in 39 cases. The three year cumulative graft patency rate was 69% for FF grafts and 48% for both types of axill...

  13. Geschlechtsspezifische Aspekte psychosozialer Variablen bei aortokoronarer Bypass-Operation

    OpenAIRE

    Dunkel, Anne

    2012-01-01

    Following coronary artery bypass graft (CABG) surgery women display not only higher mortality rates, but also report more restrictions in terms of health-related quality of life (HRQoL). So far, the causes for this gender gap could not be fully explained by clinical variables. Therefore, the aim of the present study was to analyze the role of psychosocial variables during recovery following CABG. Six specific problems concerning perioperative gender differences in HRQoL, depression, social su...

  14. Isopentenyl diphosphate (IPP)-bypass mevalonate pathways for isopentenol production.

    Science.gov (United States)

    Kang, Aram; George, Kevin W; Wang, George; Baidoo, Edward; Keasling, Jay D; Lee, Taek Soon

    2016-03-01

    Branched C5 alcohols are promising biofuels with favorable combustion properties. A mevalonate (MVA)-based isoprenoid biosynthetic pathway for C5 alcohols was constructed in Escherichia coli using genes from several organisms, and the pathway was optimized to achieve over 50% theoretical yield. Although the MVA pathway is energetically less efficient than the native methylerythritol 4-phosphate (MEP) pathway, implementing the MVA pathway in bacterial hosts such as E. coli is advantageous due to its lack of endogenous regulation. The MVA and MEP pathways intersect at isopentenyl diphosphate (IPP), the direct precursor to isoprenoid-derived C5 alcohols and initial precursor to longer chain terpenes, which makes independent regulation of the pathways difficult. In pursuit of the complete "decoupling" of the MVA pathway from native cellular regulation, we designed novel IPP-bypass MVA pathways for C5 alcohol production by utilizing promiscuous activities of two enzymes, phosphomevalonate decarboxylase (PMD) and an E. coli-endogenous phosphatase (AphA). These bypass pathways have reduced energetic requirements, are further decoupled from intrinsic regulation, and are free from IPP-related toxicity. In addition to these benefits, we demonstrate that reduced aeration rate has less impact on the bypass pathway than the original MVA pathway. Finally, we showed that performance of the bypass pathway was primarily determined by the activity of PMD. We designed PMD mutants with improved activity and demonstrated titer increases in the mutant strains. These modified pathways would be a good platform for industrial production of isopentenol and related chemicals such as isoprene. PMID:26708516

  15. Efficacy of Intravenous Acetaminophen after Coronary Artery Bypass Graft Surgery

    OpenAIRE

    Leick AM; Ratliff PD; Shely RN; Lester WC; Short MR

    2015-01-01

    In recent years, a multimodal approach to post-operative pain control consisting of opioid and non-opioid agents administered simultaneously has been used to provide synergistic effects and reduce opioid-related adverse effects. This is a retrospective, cohort study involving coronary artery bypass graft surgery patients who received scheduled intravenous IV acetaminophen 1gm every 6 hours for 4 doses starting at surgery end time with opioids administered as needed versus opioids as monother...

  16. Early chest tube removal after coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Mohsen Mirmohammad-Sadeghi

    2009-01-01

    Full Text Available Background: There is no clear data about the optimum time for chest tube removal after coronary artery bypass surgery. Aim: The aim of this study was to assess the impact of the chest tube removal time following coronary artery bypass grafting surgery on the clinical outcome of the patients. Material and Methods: An analysis of data from 307 patients was performed. The patients were randomized into two groups: in group 1 (N=107 chest tubes were removed within the first 24 hours after surgery, whereas in group 2 (N=200, chest tubes were removed in the second 24 hours after surgery. Demographics, lactate and pH at the beginning, during and after the operation, creatinine, left ventricular ejection fraction, inotropic drugs administration, length of ICU stay, and mortality data were collected. Respiratory rate and pain level was assessed. Results: In these surgeries, the mean± standard deviation for the aortic clamping time was 49.18±17.59 minutes and cardiopulmonary bypass time was 78.39±25.12 minutes. The amount of heparin consumed by the second group was higher (P <0.001 which could be considered as an important factor in increasing the drainage time after the surgery (P =0.047. The pain level evaluated 24 hours post-operation was lower in the first group, and the difference in the pain level between the 2 groups evaluated 30 hours post-operation was significant (P=0.016. The mean time of intensive care unit stay was longer in the second group but it was not statistically significant. Conclusion: Early extracting of chest tubes after coronary artery bypass graft surgery when there is no significant drainage can lead to pain reduction and consuming oxygen is an effective measure after surgery toward healing; it doesn′t increase the risk of creation of plural effusion and pericardial effusion.

  17. A 7-year, single-center research and long term follow-up of graft patency of robotic total arterial off-pump coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Guo-peng LIU

    2016-06-01

    Full Text Available Objective  The aim of the study was to explore the long-term benefits of coronary artery bypass grafting (CABG. Methods  From January 2007 to November 2014, 240 patients (187 males and 53 females, average age 59 years received robotic off-pump CABG assisted with da Vinci Surgical System (Intuitive Surgical, USA in our center. Totally endoscopic coronary artery bypass (totally robot-assisted TECAB, n=100 or mini-thoracotomy direct coronary artery bypass (free of internal mammary artery, IMA, by robot, MIDCAB, n=140 grafting was performed. Patients were followed-up regularly, and their graft patency was assessed every 6 months by coronary angiography or 64-multi-slide CT angiography. Results  All the procedures were completed successfully without conversion to median sternotomy or cardiopulmonary bypass , there was no operative mortality. 237 unilateral IMA grafts (98.7% and 3 bilateral IMA grafts (1.3% were used. Hybrid revascularization of non-left anterior descending vessels was performed in 24 patients (10%. In the follow-up of 41.1±12.9 months, no death, stroke or myocardial infarction occurred. All grafts were patent before discharge. The IMA graft patency was 97.1% in TECAB and 96.4 % in MIDCAB over 3 years (up to 91 months after surgery. Conclusions  Robotic off-pump CABG using IMA grafts is a safe and effective surgery method in selected patients. The long-term outcome and patency of IMA grafts are excellent. DOI: 10.11855/j.issn.0577-7402.2016.06.15

  18. 非体外冠状动脉移植术应用新斯的明控制心率对血流动力学的影响%Influence of controlling heart rate with Neostigmine for hemodynamics in off-pump coronary artery bypass grafting

    Institute of Scientific and Technical Information of China (English)

    刘建军

    2011-01-01

    目的 本研究采用经食道超声多普勒技术,比较新斯的明和艾司洛尔在非体外冠状动脉移植术中控制心率对血流动力学的影响.方法 40例常规非体外冠状动脉移植术中HR>80次/min的患者,随机选用这两种药物.新斯的明组(N组)每次静脉注射0.2 mg,直至心率降至65次/min左右,艾司洛尔组(A组)每次给予40 mg,心率降至65次/min止.用DATEX多功能监测仪HEMOSONICTM100经食管超声多普勒仪连续监测给药前后血流动力学各参数的变化.结果 给药后两组心率都明显减慢(P<0.01);两组相比,给药后A组较N组血压、SV、LVET、SVR、CO在1 min、2 min、3 min、5 min、7 min有明显下降,差异有统计学意义.结论 新斯的明通过间接增加乙酰胆碱的作用,使心率减慢,心输出量基本不变,较艾司洛尔更有优势.%Objective To compare the effect of controlling heart rate between Neostigmine and Esmolol Hydrochloride for hemodynamics by transesophageal Dopple technology in off-pump coronary artery bypass grafting. Methods 40 cases of patients underwent off-pump coronary artery bypass and HR>80 time points, random selection of the two types of drugs: Neostigmine of the group(N group) ,injecting Neostigmine 0. 2 mg every time, so heart rate dropped to around 65 times,the group of Esmolol Hydrochloride (A group ), injecting Esmolol Hydrochloride 40 mg every time, so heart rate dropped to a stop at 65. DATEX HEMOSONICTM100 with many functions of the transesophageal doppler,continuous monitoring to medicine and blood for a change of dynamics. Results The heart rate of two groups was significantly reduced( P<0.01) after treatment; compared with the N groups, the A group of pressure、SV、LVET、SVR、CO had noticeably in 1 min,2 min,3 min,5 min,7 min and had a significant gender difference. Conclusion Neostigmine increases the role of acetylcholine indirectly in order to decrease heart rate and steady the cardiac output and has more

  19. Assessing Patient bypass Behavior Using Taxi Trip Origin–Destination (OD Data

    Directory of Open Access Journals (Sweden)

    Gege Yang

    2016-09-01

    Full Text Available Many patients prefer to use the best hospitals even if there are one or more other hospitals closer to their homes; this behavior is called “hospital bypass behavior”. Because this behavior can be problematic in urban areas, it is important that it be reduced. In this paper, the taxi GPS data of Beijing and Suzhou were used to measure hospital bypass behavior. The “bypass behavior index” (BBI represents the bypass behavior for each hospital. The results indicated that the mean hospital bypass trip distance value ranges from 5.988 km to 9.754 km in Beijing and from 4.168 km to 10.283 km in Suzhou. In general, the bypass shares of both areas show a gradually increasing trend. The following hospitals exhibited significant patient bypass behavior: the 301 Hospital, Beijing Children’s Hospital, the Second Affiliated Hospital of Soochow University and the Suzhou Hospital of Traditional Chinese Medicine. The hospitals’ reputation, transport accessibility and spatial distribution were found to be the main factors affecting patient bypass behavior. Although the hospital bypass phenomena generally appeared to be more pronounced in Beijing, the bypass trip distances between hospitals were found to be more significant in Suzhou.

  20. Vessel enhancing diffusion: a scale space representation of vessel

    NARCIS (Netherlands)

    R. Manniesing (Rashindra); M.A. Viergever; W.J. Niessen (Wiro)

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orient

  1. Modulation method of scroll compressor based on suction gas bypass

    International Nuclear Information System (INIS)

    The air conditioners and heat pumps tend to work in much mild environments and part load situations rather than provide the rated full capacity under severe rated testing conditions. Both the capacity and inner compression ratio of the compressor should be regulated according to the working condition for higher energy efficiency and occupants’ comfort. A potential modulating technology of the scroll compressor, suction gas bypass, is investigated in this paper. The principle and operation method are illuminated and the adaptability is validated by experiments and simulations. As a conclusion, an appropriate suction gas bypass can reduce the inner compression loss of the scroll compressor under over compression conditions, enhance the system COP and also largely decrease the heating/cooling capacity of the refrigeration/heat pump system. - Highlights: ► Suction gas bypass (SGB) is an effective regulating method of scroll compressor. ► SGB reduces the inner compression loss under over compression conditions. ► SGB largely decreases the heating/cooling capacity of the refrigeration system.

  2. Percutaneous mechanical thrombectomy for treatment of acute femoropopliteal bypass occlusion

    Directory of Open Access Journals (Sweden)

    Lichtenberg M

    2012-05-01

    Full Text Available Michael Lichtenberg1, Matthias Käunicke1, Birgit Hailer1,21Cardiovascular Clinic, Vascular Center, Katholisches Klinikum Essen, Germany; 2University of Witten/Herdecke, GermanyAbstract: Acute and subacute ischemia of the legs in acute and subacute femoropopliteal bypass occlusion is a dramatic situation that endangers the survival of the limbs, depending on the severity of the ischemia. Different therapy options like percutaneous mechanical thrombectomy procedures, which include rotational thrombectomy, have become available in recent years, in addition to local lysis and surgical thrombectomy. Surgical thrombectomy using the Fogarty catheter technique, in particular, shows an increased incidence of perioperative complications but only small technical success rates in randomized trials. On the other hand, local lysis is associated with increased costs due to resource-consuming measures, such as intensive monitoring and repeat angiographies, in addition to bleeding complications. In the past, further development of the Straub Rotarex® system as an endovascular therapy option has demonstrated good success leading to amputation-free survival in multiple studies. At the same time, a low rate of complications with use has been documented. Most examinations have been conducted in the thigh. To date, there are little investigational data on its use in acutely and subacutely occluded femoropopliteal bypasses. In this paper, the current study-based significance of the Rotarex system for this indication is analyzed based on the existing literature and the authors' own experiences with 22 patients.Keywords: acute limb ischemia, femoropopliteal bypass, local lysis, rotational thrombectomy

  3. Ileal loop interposition:an alternative biliar y bypass technique

    Institute of Scientific and Technical Information of China (English)

    Felipe JF Coimbra; Alessandro L Diniz; Heber SC Ribeiro; Wilson L Costa Jr.; Eduardo NP Lima; André L Montagnini

    2010-01-01

    BACKGROUND: Obstructive jaundice is a common condition in advanced digestive cancer. Palliative procedures can improve quality of life and allow patients to attempt a systemic treatment. Bilioenteric anastomosis is still the procedure of choice for patients in many centers. When a surgical bypass is not possible, biliary drainage can be done by placing endoscopic or transparietal stents, which are less durable methods even when an expandable stent is employed. METHODS: A 47-year-old male with an excellent clinical status and a previous cholecystectomy and an exploratory laparotomy for advanced gastric cancer was referred with obstructive jaundice. A preoperative CT scan showed a dilated bile duct and a small mass at the distal hepatic hilum. No other signs of metastasis were found. A surgical bilioenteric anastomosis was indicated. At surgery, a distal choledochal obstruction and a mesenteric retraction by a lymph node mass prevented the jejunum to ascend for a bilioenteric anastomosis. Surgically, an alternative bilioenteric bypass was performed by means of an ileal loop interposition between the bile duct and the jejunum. RESULT: The recovery of the patient was uneventful and his bilirubin levels normalized after one week. The patient was then referred for systemic chemotherapy. CONCLUSIONS: This alternative biliary bypass can be safely and easily performed, and may be a good alternative for patients already referred for surgery because of a better life expectancy and when the jejunum is not an alternative.

  4. The Limit of Large Vessels

    Institute of Scientific and Technical Information of China (English)

    Yang Peiju

    2011-01-01

    On Feb 21(st),the industry was shocked by the news that AP Moller-Maersk placed an order of 10 container ships of 18,000 TEU with the South Korean ship yards.The order brings the development of large vessels to a new climax and at the same time puts forward a series of research subjects to the industry,such as what is the limit for the development of large vessels,whether ship safety can be guaranteed,and etc.

  5. Vessel dilatation in coronary angiograms

    International Nuclear Information System (INIS)

    Amongst 166 patients with aneurysms, ectasia or megaloarteries shown on coronary angiograms, 86.1% had dilated vessels as part of generalised coronary sclerosis (usually in patients with three-vessel disease). In 9%, dilatation was of iatrogenic origin and in 4.8% it was idiopathic. One patient had Marfan's syndrome. Amongst 9 000 patients, there were eight with megalo-arteries without stenosis; six of these had atypical angina and three suffered an infarct. Patients with definite dilatation of the coronary artery and stagnation of contrast flow required treatment. (orig.)

  6. Vessel dilatation in coronary angiograms

    Energy Technology Data Exchange (ETDEWEB)

    Hinterauer, L.; Goebel, N.

    1983-11-01

    Amongst 166 patients with aneurysms, ectasia or megaloarteries shown on coronary angiograms, 86.1% had dilated vessels as part of generalised coronary sclerosis (usually in patients with three-vessel disease). In 9%, dilatation was of iatrogenic origin and in 4.8% it was idiopathic. One patient had Marfan's syndrome. Amongst 9 000 patients, there were eight with megalo-arteries without stenosis; six of these had atypical angina and three suffered an infarct. Patients with definite dilatation of the coronary artery and stagnation of contrast flow required treatment.

  7. WWER reactor pressure vessel design

    International Nuclear Information System (INIS)

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. The details of WWER reactor pressure vessel design, as used in the PWR type reactors of the former USSR are given in chapter 4. General design concepts are given as well as specific material requirements. Safety concepts and lifetime assurance are discussed briefly

  8. [Pulmonary blood vessels in goats].

    Science.gov (United States)

    Roos, H; Hegner, K; Vollmerhaus, B

    1999-05-01

    The blood vessels in the lung of the goat, which until now have received little attention, are described in detail for the first time. With regard to the segments of the lung, blood vessels are bronchovascular units in the lobi craniales, lobus medius and lobus accessorius, but bronchoartery units in the lobi caudales. We investigated the types of branches of the Aa. pulmonales dextra et sinistra, the inter- and intraspecific principles of the outlet of the pulmonary veins and the importance of bronchopulmonary segmentation of the lungs. PMID:10386009

  9. 体外循环术对先天性心脏病患儿手术前后神经系统发育障碍的影响%Influence of cardiopulmonary bypass on neurodevelopmental disorder in congenital heart disease children before and after operation

    Institute of Scientific and Technical Information of China (English)

    李稼

    2014-01-01

    With the advances of medical management and surgical techniques during cardiopulmonary bypass,children with congenital heart disease are increasingly surviving to adulthood.Research into their neurodevelopmental outcomes in the past 20 years had revealed sobering realizations about the adverse impact on the quality of life of these surgical survivors.A multitude of factors contribute to the incidence and severity of neurodevelopmental abnormalities and can be separated into preoperative,intraoperative,and postoperative events,in addition to genetic contributions and socioeconomic factors.This article highlight some of current understanding of these protean factors.Understanding should lead to modification of current techniques and management strategies,all with the ultimate goal of improving patients' quality of life.%随着临床治疗和外科技术的改善,先天性心脏病患儿体外循环术后早期和长期成活率显著增加.因此,已有越来越多的患儿进入学校学习.在过去20年中,对于这些术后存活患儿神经发育的研究结果证实这些患儿的学习和生活质量受到严重影响.神经发育障碍由多种因素引起,可大致分为术前、术中和术后3类,另有基因及社会经济条件等因素.现着重阐述先天性心脏病患儿体外循环后,导致神经发育异常影响因素的最新研究进展.理解这些才能改善现有技术和治疗方法,最终改善患儿生活质量.

  10. Assessment of flow quantification in coronary bypass grafts and coronary arteries with velocity-encoded cine MR imaging; Flussquantifizierung in Koronar- und Bypassgefaessen mit der MR-Phasenkontrasttechnik

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F.; Kalden, P.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Voigtlaender, T.; Wittlinger, T.; Meyer, J. [Mainz Univ. (Germany). 2. Medizinische Klinik und Poliklinik; Dahm, M. [Mainz Univ. (Germany). Klinik fuer Herz-, Thorax-, und Gefaesschirurgie

    2000-02-01

    Materials and methods: 12 patients with 22 coronary bypass grafts underwent intraoperative flow quantification using the transit time ultrasound method. These values were compared to postoperative MR phase shift measurements. Flow measurements were performed preoperatively in 28 coronary arteries of 20 patients. For flow measurement, we used a velocity-encoded k-space segmented gradient echo sequence with a temporal resolution of 110 or 125 ms, respectively. 6-8 pase shift images could be acquired during one cardiac cycle. Results: There was a significant correlation between intraoperative and flow measurements using velocity-encoded MR imaging (r=0.76, p<0.0001, t-test). Flow volumes determined by MR imaging were systematically larger than those determined by the transit time ultrasound method. Mean flow in coronary arteries was reduced in severely stenosed vessels (>70%) compared to normal vessels. Intra- and interobserver variability were 10.5 and 15% (coronary bypass grafts), and 12.3 and 15.8% (coronary arteries), respectively. (orig.) [German] Material und Methode: Die MRT-Flussmessungen von 12 Patienten mit 22 Bypassgefaessen wurden mit intraoperativ mittels Ultraschalldurchflussmethode bestimmten Fluessen verglichen. Praeoperativ wurden zusaetzlich Flussmessungen in 28 Koronararterien von 20 Patienten durchgefuehrt. Zur MRT-Flussmessung wurde eine segmentierte 2D-Flash-Sequenz verwendet, die eine zeitliche Aufloesung von 110 bzw. 125 ms aufwies. Dies ermoeglichte die Akquisition von 6-8 Bildpaaren pro Herzzyklus. Ergebnisse: Es bestand eine signifikante Korrelation zwischen den Ergebnissen der intraoperativen und denen der postoperativen MRT-Flussmessung (r=0,76, p<0,0001, t-Test). Das mit der MRT gemessene Flussvolumen lag ueber dem bei der Ultraschallmessung ermittelten. Die Bestimmung des mittleren Flusses in den Koronararterien zeigte deutliche Unterschiede zwischen Gefaessen mit hoehergradiger Stenose (>70%) und Gefaessen ohne Stenose. Die Intra- und

  11. Quench of molten aluminum oxide associated with in-vessel debris retention by RPV internal water

    International Nuclear Information System (INIS)

    In-vessel debris coolability experiments were performed in ALPHA program at JAERI. Molten aluminum oxide (Al2O3) was poured into a pool of water in a lower head experimental vessel. Post-test observation and measurement using an ultrasonic technique indicated the formation of the interfacial gap between the solidified Al2O3 and the vessel wall. Thermal responses of the vessel wall implied that the interfacial gap acted initially as a thermal resistance and water subsequently penetrated into the interfacial gap. The maximum heat flux at the inner surface of the vessel facing to the solidified Al2O3 was roughly evaluated to be ranged from 320 kW/m2 to 600 kW/m2. A post-test analysis was conducted with CAMP code. The influence of the interfacial gap on thermal behavior of Al2O3 and the vessel wall was examined. (authors)

  12. 30 seismic analysis of FBR vessels: Coupling between components and vessels, fluid communications, imperfections

    International Nuclear Information System (INIS)

    The internal structures of a loop type breeder reactors such as SUPERPHENIX are composed of axisymmetrical shells separated by fluid volumes. Seismic analysis is usually performed by axisymmetric finite element model taking into account fluid structure interaction but the geometry is in fact 3D due to components, small communications between fluid volumes and imperfections in the vessels. The methods to take this 3D behaviour into account are based on Fourier decomposition of the motion and substructuration. They are briefly described in the following chapters. The influence of components and of small communications on a block reactor similar to SPX1 will also be presented. 15 refs, 20 figs

  13. Laparoscopic gastric bypass to robotic gastric bypass: time and cost commitment involved in training and transitioning an academic surgical practice.

    Science.gov (United States)

    Lyn-Sue, Jerome R; Winder, Josh S; Kotch, Shannon; Colello, Jacob; Docimo, Salvatore

    2016-06-01

    The Roux-en-Y gastric bypass is the gold standard procedure for weight loss. This relatively complex procedure has excellent outcomes when performed via laparoscopy. The advent of the DaVinci robotic platform has been a technological advancement. Our goal is to provide information regarding the cost, time commitment, and advantages of transitioning an LRYGB program to an RRYGB program in an academic setting. We retrospectively reviewed the last 25 laparoscopic gastric bypass procedures and the first 25 robotic gastric bypass procedures performed by a single surgeon. We compared clinical outcomes and focused on time and hospital cost during this transition phase. There was no significant demographic difference between the groups. The mean age was 41.7 (RRYGB) years vs 43.4 (LRYGM) years. The mean BMI were similar between groups, 45.3 vs 46.5 kg/m(2) for RRYGB and LRYGB. No anastomotic leaks or mortalities were noted. There was one anastomotic stricture in both groups. Excess weight loss was similar in both groups at 1 year. There was a significant increase in operative time with RRYGB, mean 241 min vs mean 174 min (p = 0.0005). Operative time fell by 25 min after the first 10 cases. The hospital cost was also increased with RRYGB mean $5922 vs $4395 (p = 0.03). Transitioning from a laparoscopic to a robotic practice can be done safely, however, the initial operative times were longer and the hospital cost was higher for robotic gastric bypass. We hope in the future that these will decrease after overcoming the learning and as the technology becomes widespread. PMID:26983848

  14. Stress analysis of the JT-60 vacuum vessel

    International Nuclear Information System (INIS)

    Stress analysis of the JT-60 vacuum vessel is reported in the parameter ranges of rigid ring thickness 40 - 70 mm and bellows thickness 2.0 - 2.5 mm for the structure in detailed design. The needs of stiffening ribs and dash-pots against the electromagnetic forces are discussed and also integrity of the vacuum vessel in plasma disruptions with time constant shorter than 50 msec. Calculations show that the maximum stress intensity produced in the vacuum vessel is below the allowable one even without the stiffening ribs and dash-pots. And, the larger the bellows thickness the higher becomes the safety margin; thickness of the rigid ring little influences the stress intensity. In plasma disruptions with time constant shorter than 1 msec, the stress intensity exceeds the allowable one. (author)

  15. Aging of reactor vessels in LWR type reactors

    International Nuclear Information System (INIS)

    Most of the degradation mechanisms of nuclear components were not included on the design so they have to be treated a posteriori, and that imply a loss of capacity. In this paper the state of the art on the reactor pressure vessel neutron embrittlement and on the irradiation assisted stress corrosion cracking that affects internal components, are explained. Special attention is devoted on the influence of the neutron fluence on IASCC process, on the material alterations promoted by irradiation and their consequences on the susceptibility to this phenomenon. Regarding the reactor pressure vessel degradation, this paper discuss the application of the Master Curve on the structural integrity evaluation of the vessel. Other aspects related to further developments are also mentioned and the importance of a good materials ageing management on the operation of the plant is pointed out. (Author) 12 refs

  16. Risk of collision between service vessels and offshore wind turbines

    International Nuclear Information System (INIS)

    Offshore wind farms are growing in size and are situated farther and farther away from shore. The demand for service visits to transfer personnel and equipment to the wind turbines is increasing, and safe operation of the vessels is essential. Currently, collisions between service vessels and offshore wind turbines are paid little attention to in the offshore wind energy industry. This paper proposes a risk assessment framework for such collisions and investigates the magnitude of the collision risk and important risk-influencing factors. The paper concludes that collisions between turbines and service vessels even at low speed may cause structural damage to the turbines. There is a need for improved consideration of this kind of collision risk when designing offshore wind turbines and wind farms.

  17. Aircraft crash analysis of the proposed sizewell B containment vessel

    International Nuclear Information System (INIS)

    This paper attempts to examine the behaviour of the proposed sizewell B containment vessel under the impact of a multi-role combat aircraft such as a Tornado and Phantom RF-4E. A 600 section of the containment vessel is analysed using three dimensional 20 noded isoparametric finite elements adopted in Program CRASH. The impact area under consideration is 28 m2 which is evaluated from the data obtained from these two aircraft. The vessel is assumed to have unbonded tendons both in the dome and in the barrel wall. The influence of the liner is included in evaluating resistance to the impact. A three-dimensional time dependent impact analysis is carried out which incorporates, direct integration concept. The final results obtained include displacements, velocities, accelerations; concrete scabbing, perforation and general cracking. The final damage is shown in a specially prepared post-mortem diagram. The paper has an appendix summarising the constitutive equations for the proposed numerical model. (orig.)

  18. Reactor pressure vessel structural integrity research

    Energy Technology Data Exchange (ETDEWEB)

    Pennell, W.E.; Corwin, W.R. [Oak Ridge National Lab., TN (United States)

    1995-04-01

    Development continues on the technology used to assess the safety of irradiation-embrittled nuclear reactor pressure vessels (RPVs) containing flaws. Fracture mechanics tests on RPV steel, coupled with detailed elastic-plastic finite-element analyses of the crack-tip stress fields, have shown that (1) constraint relaxation at the crack tip of shallows surface flaws results in increased data scatter but no increase in the lower-bound fracture toughness, (2) the nil ductility temperature (NDT) performs better than the reference temperature for nil ductility transition (RT{sub NDT}) as a normalizing parameter for shallow-flaw fracture toughness data, (3) biaxial loading can reduce the shallow-flaw fracture toughness, (4) stress-based dual-parameter fracture toughness correlations cannot predict the effect of biaxial loading on a shallow-flaw fracture toughness because in-plane stresses at the crack tip are not influenced by biaxial loading, and (5) an implicit strain-based dual-parameter fracture toughness correlation can predict the effect of biaxial loading on shallow-flaw fracture toughness. Experimental irradiation investigations have shown that (1) the irradiation-induced shift in Charpy V-notch vs temperature behavior may not be adequate to conservatively assess fracture toughness shifts due to embrittlement, and (2) the wide global variations of initial chemistry and fracture properties of a nominally uniform material within a pressure vessel may confound accurate integrity assessments that require baseline properties.

  19. Passage of downstream migrant American eels through an airlift-assisted deep bypass

    Science.gov (United States)

    Haro, Alexander J.; Watten, Barnaby J.; Noreika, John

    2016-01-01

    Traditional downstream guidance and bypass facilities for anadromous fishes (i.e., surface bypasses, surface guidance structures, and behavioral barriers) have frequently been ineffective for anguillid eels. Because eels typically spend the majority of their time near the bottom in the vicinity of intake structures, deep bypass structures with entrances near the bottom hold promise for increased effectiveness, thereby aiding in the recovery of this important species. A new design of a deep bypass system that uses airlift technology (the Conte Airlift Bypass) to induce flow in a bypass pipe was tested in a simulated intake entrance environment under controlled laboratory conditions. Water velocities of 0.9–1.5 m s−1 could be generated at the bypass entrance (opening with 0.073 m2 area), with corresponding flows through the bypass pipe of 0.07–0.11 m3 s−1. Gas saturation and hydrostatic pressure within the bypass pipe did not vary appreciably from a control (no air) condition under tested airflows. Migratory silver-phase American eels (Anguilla rostrata) tested during dark conditions readily located, entered, and passed through the bypass; initial avoidance rates (eels approaching but not entering the bypass entrance) were lower at higher entrance velocities. Eels that investigated the bypass pipe entrance tended to enter headfirst, but those that then exited the pipe upstream did so more frequently at lower entrance velocities. Eels appeared to swim against the flow while being transported downstream through the pipe; median transit times through the bypass for each test velocity ranged from 5.8 to 12.2 s, with transit time decreasing with increasing entrance velocity. Eels did not show strong avoidance of the vertical section of the pipe which contained injected air. No mortality or injury of bypassed eels was observed, and individual eels repeatedly passed through the bypass at rates of up to 40 passes per hour, suggesting that individuals do not

  20. Perioperative risk factors for prolonged mechanical ventilation and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Zahra S Faritous

    2011-01-01

    Full Text Available Background: Prolonged mechanical ventilation is an important recognized complication occurring during cardiovascular surgery procedures. This study was done to assess the perioperative risk factors related to postoperative pulmonary complications and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass. Methods: It was a retrospective study on 5,497 patients, including 31 patients with prolonged ventilatory support and 5,466 patients without it; from the latter group, 350 patients with normal condition (extubated in 6-8 hours without any complication were selected randomly. Possible perioperative risk factors were compared between the two groups using a binary logistic regression model. Results: Among the 5,497 women undergoing coronary artery bypass graft (CABG, 31 women needed prolonged mechanical ventilation (PMV, and 15 underwent tracheostomy. After logistic regression, 7 factors were determined as being independent perioperative risk factors for PMV. Discussion: Age ≥70 years old, left ventricular ejection fraction (LVEF ≤30%, preexisting respiratory or renal disease, emergency or re-do operation and use of preoperative inotropic agents are the main risk factors determined in this study on women undergoing CABG.

  1. Commercial Passenger Fishing Vessel Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the logbook data from U.S.A. Commercial Passenger Fishing Vessels (CPFV) fishing in the U.S.A. EEZ and in waters off of Baja California, from...

  2. Vacuum vessel of thermonuclear device

    International Nuclear Information System (INIS)

    An innermost wall joining portion and an outermost wall joining portion are disposed at the innermost and the outermost walls of ribs secured to sector pieces at both ends which constitutes a vacuum vessel, to which first inner wall pieces and first outer wall pieces used for walls of a vacuum vessel at a first stage of assembling are connected. In addition, an inner wall joining portion and an outer wall joining portion are disposed to a portion inner than the innermost and the outermost walls of the rib, to which second inner wall pieces and, outer wall pieces to be used as walls of the vacuum vessel are connected upon reassembling of walls. Since robots can access easily from the inner side of the vacuum vessel, the first inner wall pieces and the outer wall pieces are each connected to the innermost and the outermost wall connection portions upon initial stage of the assembly, and the second inner wall pieces and outer wall pieces are connected to the inner and outer wall connection portions previously fabricated other than cutting portions at high accuracy and high strength upon reassembling of walls. (N.H.)

  3. The Vessel Schedule Recovery Problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Plum, Christian Edinger Munk; Vaaben, Bo;

    Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker...

  4. Effects of different levels of positive airway pressure on breathing pattern and heart rate variability after coronary artery bypass grafting surgery

    OpenAIRE

    C.B.F. Pantoni; L. Di Thommazo; R.G. Mendes; A.M. Catai; Luzzi, S.; O. Amaral Neto; A. Borghi-Silva

    2011-01-01

    The application of continuous positive airway pressure (CPAP) produces important hemodynamic alterations, which can influence breathing pattern (BP) and heart rate variability (HRV). The aim of this study was to evaluate the effects of different levels of CPAP on postoperative BP and HRV after coronary artery bypass grafting (CABG) surgery and the impact of CABG surgery on these variables. Eighteen patients undergoing CABG were evaluated postoperatively during spontaneous breathing (SB) and a...

  5. Thermal hydraulic design of the mercury target vessel

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency (JAEA) has completed the mercury target system as the pulsed spallation neutron source of J-PARC project, which has the highest level power of 1MW in the world. The basic design of the flow channel and structure of the mercury target vessel, which is the core of the neutron source, was carried out by JAEA, and the detail design, parts fabrication and assembling have been carried out by the vendor from 2003. Taking these fabrication designs and assembling conditions into consideration, the final performance evaluation of the mercury target vessel was carried out from the viewpoint of thermal hydraulics. The general thermal hydraulic analyses code, STAR-CD, was used, and the thermal hydraulic analyses were carried out for the mercury flow in the mercury vessel and the heavy water flow in the safety hull, taking the nuclear heating and the heat transportation into consideration. The analytical model was three dimensional. The total cell number of the mercury vessel and mercury was 1.78 x 106 and that of the safety hull was 2.39 x 106. The standard k-ε model and MARS were adopted as the basic combination of the turbulence model and the differential scheme, but other combinations, such as RNG k-ε model and UD were also used as a reference. Comparing these analytical results, it was confirmed that the mercury target vessel fulfills the design requirements such as the fluid inlet velocity, the maximum temperature of fluid, the maximum temperature of the vessel, the pressure drop of fluid, etc. The influence of the welding deformation of the mercury target vessel was also evaluated. Mercury flow and heavy water flow are affected a little, but they do not much extend the required condition, and the structural integrity was confirmed. (author)

  6. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63... BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s) and vessel(s) are interchangeable or synonymous words, and include every description of...

  7. Coronary artery bypass grafting versus percutaneous intervention in coronary revascularization: a historical perspective and review

    Directory of Open Access Journals (Sweden)

    Burgess SN

    2015-06-01

    Full Text Available Sonya N Burgess,1 John J Edmond,2 Craig P Juergens,1 John K French11Department of Cardiology, Liverpool Hospital and South Western Sydney Clinical School, The University of New South Wales, Sydney, NSW, Australia; 2Department of Cardiology, Dunedin Public Hospital, Dunedin, New Zealand Background: Coronary artery bypass graft surgery is arguably the most intensively studied surgical procedure, and percutaneous coronary intervention (PCI has been subjected to more randomized clinical trials than any other interventional procedure. Changes seen in revascularization techniques have been numerous. The rapid evolution of evidence-based revascularization procedures has occurred as a result of many pivotal large randomized clinical trials. Objective: This review compares and contrasts outcomes from two coronary revascularization techniques, coronary artery bypass grafting (CABG and PCI, with particular reference to the landmark trials that inform practice guidelines. Methods: We undertook a comprehensive review of published literature addressing trials in this field performed to address current knowledge both in the predrug-eluting stent and postdrug-eluting stent era. Results and discussion: Surgical and percutaneous revascularization strategies have different strengths and weaknesses, and neither strategy is superior in all patients, clinical presentations, or anatomical subgroups. Current data support the use of percutaneous intervention in ST elevation myocardial infarction and in single-vessel disease. In noncomplex multivessel disease and isolated left main stem PCI, the data support non-inferiority of PCI compared to CABG as reflected in the 2014 European Society of Cardiology guidelines. Landmark revascularization trials of multivessel disease comparing CABG to PCI found no survival benefit to CABG over PCI, except in patients with complex disease. In these trials, revascularization drove differences in primary endpoints and in all but the

  8. Reactor vessel lower head integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, A.M.

    1997-02-01

    On March 28, 1979, the Three Mile Island Unit 2 (TMI-2) nuclear power plant underwent a prolonged small break loss-of-coolant accident that resulted in severe damage to the reactor core. Post-accident examinations of the TMI-2 reactor core and lower plenum found that approximately 19,000 kg (19 metric tons) of molten material had relocated onto the lower head of the reactor vessel. Results of the OECD TMI-2 Vessel Investigation Project concluded that a localized hot spot of approximately 1 meter diameter had existed on the lower head. The maximum temperature on the inner surface of the reactor pressure vessel (RPV) in this region reached 1100{degrees}C and remained at that temperature for approximately 30 minutes before cooling occurred. Even under the combined loads of high temperature and high primary system pressure, the TMI-2 RPV did not fail. (i.e. The pressure varied from about 8.5 to 15 MPa during the four-hour period following the relocation of melt to the lower plenum.) Analyses of RPV failure under these conditions, using state-of-the-art computer codes, predicted that the RPV should have failed via local or global creep rupture. However, the vessel did not fail; and it has been hypothesized that rapid cooling of the debris and the vessel wall by water that was present in the lower plenum played an important role in maintaining RPV integrity during the accident. Although the exact mechanism(s) of how such cooling occurs is not known, it has been speculated that cooling in a small gap between the RPV wall and the crust, and/or in cracks within the debris itself, could result in sufficient cooling to maintain RPV integrity. Experimental data are needed to provide the basis to better understand these phenomena and improve models of RPV failure in severe accident codes.

  9. Adherence to treatment after coronary bypass surgery: Psychological aspects

    Directory of Open Access Journals (Sweden)

    Maria V. Iakovleva

    2016-01-01

    Full Text Available Poor adherence to treatment is a problem of great importance and striking magnitude. Its consequences are increased health care costs and poor health outcomes. It defined the objective of this research, which is the study of psychological characteristics of patients with different degrees of adherence to rehabilitation treatment after coronary bypass surgery. Ninety male and female patients with CHD, aged 46---71, were examined. The study was carried out using the questionnaire of ways of coping and the technique for diagnosing the types of attitude toward the disease, and the study of medical history. The analysis of the types of attitude toward the disease revealed that adherent patients show higher values on the harmonious type; patients with poor adherence show higher values on the apathetic, as well as the melancholic type of attitude toward illness. This study shows that wide range of psychological characteristics is significant for the definition of adherence to treatment. It is essential to consider the patient’s personality and his characteristics, such as attitude toward the disease, because they influence the adherence and, therefore, the effectiveness of therapy in the postoperative period. La escasa adherencia a la terapia es un problema de gran importancia ampliamente extendido. Sus consecuencias son el aumento de costes del tratamiento y su baja eficacia. El objetivo de la investigación fue el estudio de las características psicológicas de pacientes con diferentes grados de adherencia al tratamiento de rehabilitación después de la cirugía de derivación coronaria. Se recogieron datos clínicos de 90 pacientes de ambos sexos con cardiopatía coronaria, sometidos a cirugía de derivación coronaria, con edades comprendidas entre 46-71 a˜nos. Los cuestionarios administrados fueron el cuestionario de estilos de afrontamiento y la técnica de diagnóstico de tipos de actitud hacia la enfermedad. Además se realizó un estudio

  10. Effects of topical hypothermia on postoperative inflammatory markers in patients undergoing coronary artery bypass surgery

    OpenAIRE

    Kadan, Murat; Erol, Gokhan; Savas Oz, Bilgehan; Arslan, Mehmet

    2014-01-01

    Summary Background We aimed to examine the effects of topical hypothermia on inflammatory markers in patients undergoing coronary artery bypass surgery. Methods Fifty patients undergoing isolated coronary artery bypass surgery were included the study. They were randomised to two groups. Mild hypothermic cardiopulmonary bypass (28–32°C) was performed on both groups using standardised anaesthesiology and surgical techniques. Furthermore, topical cooling with 4°C saline was performed on patients...

  11. Why caretakers bypass Primary Health Care facilities for child care - a case from rural Tanzania

    OpenAIRE

    Kahabuka Catherine; Kvåle Gunnar; Moland Karen; Hinderaker Sven

    2011-01-01

    Abstract Background Research on health care utilization in low income countries suggests that patients frequently bypass PHC facilities in favour of higher-level hospitals - despite substantial additional time and financial costs. There are limited number of studies focusing on user's experiences at such facilities and reasons for bypassing them. This study aimed to identify factors associated with bypassing PHC facilities among caretakers seeking care for their underfive children and to expl...

  12. Cost Performance and Efficacy of Off-pump Coronary Artery Bypass Grafting

    OpenAIRE

    Nomura, Fumikazu; Mukai, Shogo; Tamura, Kentaro; Shimazutsu, Kazufumi; Okuma, Kazuhide; Ihara, Katsuhiko

    2002-01-01

    Off-pump coronary artery bypass grafting (Off-Pump CABG) may provide an alternative form of surgical revascularization by avoiding the unwanted complications of cardiopulmonary bypass, particularly in high-risk patients. To clarify the efficacy and cost performance of Off- Pump CABG, we studied the postoperative course of Off-Pump CABG and compared it to On- pump coronary artery bypass grafting (On-Pump CABG). From Aug. 1998 to Feb. 2002, twenty-eight patients who had preoperative complicatio...

  13. Multiple Rad5 activities mediate sister chromatid recombination to bypass DNA damage at stalled replication forks

    OpenAIRE

    Minca, Eugen C; Kowalski, David

    2010-01-01

    DNA damage that blocks replication is bypassed in order to complete chromosome duplication and preserve cell viability and genome stability. Rad5, a PCNA polyubiquitin ligase and DNA-dependent ATPase in yeast, is orthologous to putative tumor suppressors and controls error-free damage bypass by an unknown mechanism. To identify the mechanism in vivo, we investigated the roles of Rad5 and analyzed the DNA structures that form during damage bypass at site-specific stalled forks present at repli...

  14. Dopexamine increases internal mammary artery blood flow following coronary artery bypass grafting.

    LENUS (Irish Health Repository)

    Flynn, Michael J

    2012-02-03

    OBJECTIVE: Vasoactive agents and inotropes influence conduit-coronary blood flow following coronary artery bypass grafting (CABG). It was hypothesized that dopexamine hydrochloride, a dopamine A-1 (DA-1) and beta(2) agonist would increase conduit-coronary blood flow. A prospective randomized double blind clinical trial was carried out to test this hypothesis. DA-1 receptors have previously been localized to human left ventricle. METHODS: Twenty-six American Society of Anaesthesiology class 2-3 elective coronary artery bypass graft patients who did not require inotropic support on separation from cardiopulmonary bypass (CPB) were studied. According to a randomized allocation patients received either dopexamine (1 microg\\/kg per min) or placebo (saline) by intravenous infusion for 15 min. Immediately prior to and at 5,10 and 15 min of infusion, blood flow through the internal mammary and vein grafts (Transit time flow probes, Transonic Ltd.), heart rate, cardiac index, mean arterial pressure and pulmonary haemodynamics were noted. The data were analysed using multivariate analysis of variance. RESULTS: Low-dose dopexamine (1 microg\\/kg per min) caused a significant increase in mammary graft blood flow compared to placebo at 15 min of infusion (P=0.028, dopexamine group left internal mammary artery (LIMA) flow of 43.3+\\/-14.2 ml\\/min, placebo group LIMA flow at 26.1+\\/-16.3 ml\\/min). Dopexamine recipients demonstrated a non-significant trend to increased saphenous vein graft flow (P=0.059). Increased heart rate was the only haemodynamic change induced by dopexamine (P=0.004, dopexamine group at 85.2+\\/-9.6 beats\\/min and placebo group at 71.1+\\/-7.6 beats\\/min after 15 min of infusion). CONCLUSION: This study demonstrates that administration of dopexamine (1 microg\\/kg per min) was associated with a significant increase in internal mammary artery graft blood flow with mild increase in heart rate being the only haemodynamic change. Low-dose dopexamine may

  15. Iterative Vessel Segmentation of Fundus Images.

    Science.gov (United States)

    Roychowdhury, Sohini; Koozekanani, Dara D; Parhi, Keshab K

    2015-07-01

    This paper presents a novel unsupervised iterative blood vessel segmentation algorithm using fundus images. First, a vessel enhanced image is generated by tophat reconstruction of the negative green plane image. An initial estimate of the segmented vasculature is extracted by global thresholding the vessel enhanced image. Next, new vessel pixels are identified iteratively by adaptive thresholding of the residual image generated by masking out the existing segmented vessel estimate from the vessel enhanced image. The new vessel pixels are, then, region grown into the existing vessel, thereby resulting in an iterative enhancement of the segmented vessel structure. As the iterations progress, the number of false edge pixels identified as new vessel pixels increases compared to the number of actual vessel pixels. A key contribution of this paper is a novel stopping criterion that terminates the iterative process leading to higher vessel segmentation accuracy. This iterative algorithm is robust to the rate of new vessel pixel addition since it achieves 93.2-95.35% vessel segmentation accuracy with 0.9577-0.9638 area under ROC curve (AUC) on abnormal retinal images from the STARE dataset. The proposed algorithm is computationally efficient and consistent in vessel segmentation performance for retinal images with variations due to pathology, uneven illumination, pigmentation, and fields of view since it achieves a vessel segmentation accuracy of about 95% in an average time of 2.45, 3.95, and 8 s on images from three public datasets DRIVE, STARE, and CHASE_DB1, respectively. Additionally, the proposed algorithm has more than 90% segmentation accuracy for segmenting peripapillary blood vessels in the images from the DRIVE and CHASE_DB1 datasets. PMID:25700436

  16. Effects of parent vessel geometry on intraaneurysmal flow patterns

    Science.gov (United States)

    Castro, Marcelo A.; Putman, Christopher M.; Cebral, Juan R.

    2006-03-01

    This study shows the influence of the upstream parent artery geometry on intra-aneurysmal hemodynamics of cerebral aneurysms. Patient-specific models of four cerebral aneurysms at four typical locations were constructed from 3D rotational angiography images. Two geometrical models were constructed for each patient, one with the native parent vessel geometry and another with the parent vessel truncated approximately 1cm upstream from the aneurysm. For one aneurysm, two images were used to construct a model as realistic and large as possible - down to the carotid bifurcation - which was cut at seven different locations. Corresponding finite element grids were generated and computational fluid dynamics simulations were carried out under pulsatile flow conditions. It was found that truncated models tended to underestimate the wall shear stress in the aneurysm and to shift the impaction zone to the neck when compared with the native geometry. In one aneurysm the parent vessel included a tortuous segment close to the neck that strongly influenced the flow pattern entering the aneurysm. Thus, including longer portions of the parent vessel beyond this segment did not have a substantial effect. Depending on the dominant geometrical features the length of the parent artery needed for an accurate representation of the intraaneurysmal hemodynamics may vary among individuals. In conclusion, failure to properly model the inflow stream determined by the upstream parent artery can significantly influence the results of intra-aneurysmal hemodynamic models. The upstream portion of the parent vessel of cerebral aneurysms should be included in order to accurately represent the intraaneurysmal hemodynamics.

  17. Numerical simulation of magnetic nanoparticles targeting in a bifurcation vessel

    Energy Technology Data Exchange (ETDEWEB)

    Larimi, M.M.; Ramiar, A., E-mail: aramiar@nit.ac.ir; Ranjbar, A.A.

    2014-08-01

    Guiding magnetic iron oxide nanoparticles with the help of an external magnetic field to its target is the principle behind the development of super paramagnetic iron oxide nanoparticles (SPIONs) as novel drug delivery vehicles. The present paper is devoted to study on MDT (Magnetic Drug Targeting) technique by particle tracking in the presence of magnetic field in a bifurcation vessel. The blood flow in bifurcation is considered incompressible, unsteady and Newtonian. The flow analysis applies the time dependent, two dimensional, incompressible Navier–Stokes equations for Newtonian fluids. The Lagrangian particle tracking is performed to estimate particle behavior under influence of imposed magnetic field gradients along the bifurcation. According to the results, the magnetic field increased the volume fraction of particle in target region, but in vessels with high Reynolds number, the efficiency of MDT technique is very low. Also the results showed that in the bifurcation vessels with lower angles, wall shear stress is higher and consequently the risk of the vessel wall rupture increases. - Highlights: • Fluid flow and magnetic nanoparticles behavior under influence of external magnetic field are modeled in this study. • Increasing magnetic number increases size and number of recirculation zones. • Increasing Reynolds number reduces the efficiency of magnetic drug targeting. • Number of particles delivered to target region decreases with reducing the diameter of nanoparticles. • Decreasing the ratio of particle diameter to magnetic core diameter (D{sub p}/D{sub m}) will increase magnetic drug targeting efficiency.

  18. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... open-heart surgery, you would use a heart team. Most people rotate through and they do fine. ... newer concept of hybrid revascularization where the cardiologist manages one or two vessels and the surgeon manages ...

  19. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... that you need to be a proficient off-pump surgeon, meaning a beating heart surgeon. To me, ... circumflex vessel. Here, we're doing this off-pump, using a stabilizing technique and I have the ...

  20. Robot-Assisted Minimally Invasive Coronary Artery Bypass Surgery Operation

    Medline Plus

    Full Text Available ... I'm freeing up the vein and this white vessel here is actually the artery. 00:24: ... going to the circumflex artery, which is the white straight line underneath. Off. That tells me that ...