The aim of this paper is to analyse the situation of aviation and air traffic in European Union and to present the relation between the number of passengers of counties on the Old Continent, which ...will make it possible to observe the relationship and identify the causes of changes. The average growth rate is also presented in this contribution. Such an analysis may be helpful in preparing airports for increasing traffic in the future. A statistical analysis of selected aspects may enable to reveal the situation related to air transport in Europe and the predictions might visualise expectations in the following years. In this paper, the methods of statistical analysis and interpretations of studies presented in a graphical way, were used. The aim of the research was to understand the dependences between countries, trends of annual growth as well as relations between number of passengers with the gross domestic product. It was observed that the number of travelled people is growing as a function of time and it is dependent with the gross domestic product. The analyzed lands have been divided into five group according the average number of passengers. Similar tendencies have been observed in most of the cases.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An adaptive boundary control strategy is developed for the suppression of store induced oscillations in the bending and twisting deflections of an uncertain flexible aircraft wing. A Lyapunov-based ...stability analysis is used to show that the total energy in the system, and hence the distributed states of the system, remains bounded and decays asymptotically to zero. Simulation results illustrate the performance of the developed controller.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Objectives: The outcome of patients undergoing aortic valve replacement (AVR) may be affected by the influence of prosthesis–patient mismatch on left ventricular mass regression. However, due to the ...discrepancies in labeled valve size, size of sizer and actual valve dimension, it is difficult to compare different valve types. In order to perform an objective comparison, this study was designed to compare the hemodynamics of the Edwards Lifescience pericardial (ELP) and the Medtronic Mosaic porcine (MM) bioprosthesis between patients receiving the same valve size and between patients with the same aortic annulus diameter. Methods: This prospective, randomized study was performed on 81 hospital survivors out of 86 patients undergoing AVR with either the ELP (n=39) or the MM (n=42) bioprosthesis. Intra-operative randomization was performed after the surgeon had excised the aortic valve, measured the size of the aortic annulus with three different sizers (ELP, MM and a set of metric sizers), and decided which size he would implant for either of the valve types. All valves were implanted in supra-annular position with the same implantation technique. Echocardiographic follow-up was performed early postoperatively and 6 months thereafter. Results: In 12 (31%) of the patients receiving the ELP-valve, as compared to 3 (7.1%) of the patients receiving the MM-valve, the labeled valve size was smaller than the aortic annulus diameter (P<0.05). Early postoperatively, mean (17.4±3.1 vs 20.3±3.6 mmHg) and peak gradients (30.1±4.8 vs 37.6±9.6 mmHg) for the 21 mm ELP-valve were lower than for the 21 mm MM-valve (P<0.05). All other hemodynamic parameters did not show significant differences at any time point. When the same aortic annulus diameter was taken as a reference, there were no significant hemodynamic differences between either valve type at any time point, regardless of the valve size implanted. Conclusions: This study demonstrates that the hemodynamic performance of the ELP and the MM bioprosthesis are comparable when the same aortic annulus diameter is taken as a reference. The significant variabilities between different valve types with regard to labeled valve size, valve-sizer size and actual valve size have to be taken into account, when hemodynamic comparisons are performed.
Objective: Structural differences of the pulmonary root may predispose it to progressive dilatation in the systemic circulation after the Ross operation. We identified the incidence and risk factors ...of pulmonary autograft root dilatation. Methods: One hundred and seven adult patients (mean age of 36±11 years) were followed after the Ross operation since 1991 including an echocardiogram within 3 months of surgery and yearly clinical assessment and echocardiography. The autograft was measured at the maximum diameter of the sinus (SV) and aortic insufficiency (AI) assessed. A SV of ≫37 mm was considered as root dilatation and the incidence over time was calculated using the Kaplan–Meier method. Clinically relevant dilatation was defined as a root diameter of ≫42 mm. In addition, we determined the percentage change of the sinus diameter between the early and latest echocardiogram. Furthermore we tested the influence of patient variables and risk factors on dilatation. Results: By 1 year, dilatation was found in 21 patients (20%). The SV was ≫42 mm in eight patients (7%). By 7 years, only 45% of patients were free of dilatation. Eleven patients (10%) had a SV of ≫42 mm. Increase in SV was time related and linear. However, 90% of patients showed ≪25% dilatation during follow-up. Time from operation, early SV diameter, male gender and surgical technique were identified as significant risk factors of dilatation. However, dilatation has not lead to reoperation due to aneurysm formation or development of significant AI. Conclusions: We conclude that time dependent autograft root dilation occurs but does not cause an increase in AI and need for reoperation up to 7 years. These findings warrant the pursuit of the concept of the Ross operation in young patients who regain excellent functional status and life style without anticoagulation.
In murine and rat cardiac myocytes the gp130 system transduces survival as well as hypertrophic signals and via induction of the expression of the potent angiogenic factor VEGF in these cells also ...indirectly contributes to cardiac repair processes through the development of new blood vessels. There are, however, species differences in receptor specificity and receptor crossreactivity in the gp130-gp130 ligand system. We asked whether gp130 signaling is also involved in the regulation of VEGF in human cardiac myocytes and if so which gp130 ligands are critical for such an effect.
Human adult cardiac myocytes (HACMs) were isolated from myocardial tissue and characterised by positive staining for myocardial actin, troponin-I and cardiotin. HACMs were treated with the gp130 ligands CT-1, IL-6, LIF or OSM and VEGF-1 was determined by a specific ELISA in the conditioned media of these cells. RT-PCR and Western blot analysis was used in order to detect gp130, IL-6-receptor, LIF-receptor or OSM-receptor specific protein and mRNA in human adult cardiac myocytes and for detection of VEGF-1 specific mRNA in cardiac myocytes after incubation with OSM. Pieces of myocardial tissue were incubated ex vivo in the presence and absence of OSM and VEGF was determined in supernatants of these cultures and immunohistochemistry was performed on the tissue using specific antibodies for VEGF-1. Immunohistochemistry was also employed to detect VEGF in sections from a healthy human heart and in a heart from a patient suffering from acute myocarditis.
OSM, but not CT-1, IL-6 or LIF increased VEGF-1 production in human adult cardiac myocytes dose-dependently derived from five different donors. This selective stimulation of VEGF by gp130 ligands was also reflected by a specific receptor expression on these cells. We detected high levels of mRNA for gp130 and the OSM receptor in freshly isolated human cardiac myocytes but only low amounts of mRNA for the IL-6 receptor whereas mRNA for the LIF receptor was hardly detectable by RT-PCR. OSM receptor and IL-6 receptor were also detectable by Western blotting whereas LIF receptor was only present as a faint band. OSM also increased the expression of VEGF-1 mRNA in cardiac myocytes. When pieces of human myocardial tissue were incubated with the gp130 ligands in an ex vivo model only OSM resulted in an increase in VEGF-1 in the supernatants of these cultures. Furthermore, VEGF increased in tissue samples treated with OSM in cardiac myocytes as evidenced by immunohistochemistry. In addition, we found increased VEGF-1 expression in myocardial tissue from a patient suffering from acute myocarditis.
The gp130-gp130 ligand system is also involved in VEGF regulation in human cardiac myocytes and OSM is the gp130 ligand responsible for this effect in the human system whereas LIF and CT-1 which had been shown to regulate VEGF expression in mouse and rat cardiac myocytes had no effect. Thus we have added OSM, which is produced by activated T lymphocytes and monocytes, to the list of regulatory molecules of VEGF production in the human heart. Our results lend further support to the notion that besides hypoxia, inflammation via induction of VEGF through autocrine or paracrine pathways plays a key role in (re)vascularisation of the myocardium.
The surgical management of a 56-year-old patient with a single thoracic stab wound penetrating the left innominate vein and the aortic arch is described. Repair was successfully achieved using ...extracorporal circulation and circulatory arrest during deep hypothermia. Clinical features and surgical approach are described and discussed in detail.
EuroSCORE is widely used to assess operative risk. Combined cardiac procedures carry increased perioperative mortality, but the influence of preoperative factors on mid-term outcome is not well known ...for these patients. The study aim was to determine if EuroSCORE risk influences mid-term survival after combined coronary artery bypass grafting (CABG) and valve surgery.
Follow up (mean 23.7 months) was obtained in 258 consecutive hospital survivors (148 males, 110 females; median age 72.29 years; mean EuroSCORE 7 points) operated on between January 1998 and March 2001. CABG + aortic valve replacement (AVR) was performed in 171 patients, CABG + mitral surgery in 72, and CABG + double valve surgery in 15. Kaplan-Meier estimates were calculated for survival and combined freedom from death and NYHA class III/IV. The Cox regression model was applied to prove the influence of EuroSCORE risk and a number of preoperative and operative variables on mid-term outcome.
Thirty patients (11.63%) died during follow up, and 34 (13.17%) were in NYHA class III/IV. Freedom from death and NYHA class III/IV was 89.3%, 74.7% and 55.2% at 12, 24 and 36 months, respectively. The significant predictor for combined death and NYHA class III/IV was EuroSCORE risk (p = 0.0004). In the subgroup of patients with CABG + mitral valve surgery, age was identified as a significant risk factor for death (p = 0.0346), whereas in the subgroup of patients with CABG + AVR EuroSCORE was detected as significant risk factor for combined death and NYHA class III/IV.
EuroSCORE is an important predictor for poor mid-term outcome after combined CABG and valve surgery.
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