AIM:To assess the cost savings of reloading the multiband ligator in endoscopic esophageal variceal ligation (EVL) used on the same patient for subsequent sessions. METHODS:This single centre retrospective descriptive...AIM:To assess the cost savings of reloading the multiband ligator in endoscopic esophageal variceal ligation (EVL) used on the same patient for subsequent sessions. METHODS:This single centre retrospective descriptive study analysed patients undergoing variceal ligation at a tertiary care centre between 1st January, 2003 and 30th June, 2006. The multiband ligator was reloaded with six hemorrhoidal bands using hemorrhoidal ligator for the second and subsequent sessions. Analysis of cost saving was done for the number of follow-up sessions for the variceal eradication. RESULTS:A total of 261 patients underwent at least one session of endoscopic esophageal variceal ligation between January 2003 and June 2006. Out of 261, 108 patients (males 67) agreed to follow the eradication program and underwent repeated sessions. A total of 304 sessions was performed with 2.81 sessions per patient on average. Thirty-two patients could not complete the programm. In 76 patients (70%), variceal obliteration was achieved. The ratio of the costs for the session with reloaded ligator versus a session with a new ligator was 1:2.37. Among the patients who completed esophageal varices eradication, cost saving with reloaded ligator was 58%. CONCLUSION:EVL using reloaded multiband ligators for the follow-up sessions on patients undergoing variceal eradication is a cost saving procedure. Reloading the ligator thus is recommended especially for developing countries where most of the patients are not health insured.展开更多
This research presents an experimental and analytical study of the structural state of the 60/40 brass cartridge case, (BCC) after being fired. The oral section of the BCC has the function of confining the gases of fi...This research presents an experimental and analytical study of the structural state of the 60/40 brass cartridge case, (BCC) after being fired. The oral section of the BCC has the function of confining the gases of firing by expanding against the chamber and sealing the gases. Firing conditions, namely, high pressure and temperature, 3000 bar and 2727°C, respectively, affect performance properties of the (BCC). These are confining and crack strengths. Experimental study was done on the oral section to address these effects on the structural and mechanical properties of this brass. This alloy is a 60% copper (Cu) and 40% zinc (Zn) alloy and has a two-phase structure, alpha, (α) and beta, (β). Using “before and after” comparison approach;performance properties were tested in cartridge cases prepared before and after firing. These properties are hardness, tensile strength, micro-structural and chemical composition. Comparing the tests’ results, after firing demonstrated considerable degrading in performance properties, micro-structural disorder and a remarkable deficiency in the zinc element in the brass structure. This deficiency affects the percentage of beta phase in the alloy which governs the strength of the brass. According to the required properties before firing, it was found that after firing, the brass cartridge case is not qualified for reloading.展开更多
In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high mag...In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high magnitude(such that the solid medium can be under plastic compression)to a subsequently very low quantity(so that cavitation can occur in the fluid).New techniques are also developed in the definition of the ghost fluid status when the structure is under plastic deformation or when the flow is under cavitation next to the structure.Numerical results show that the improved MGFM for treatment of the fluid-deformable structure coupling works efficiently for all pressure ranges and is capable of simulating cavitation evolution and cavitation re-loading in conjunction with the employment of the isentropic one-fluid cavitation model.展开更多
We use an actuarial approach to estimate the valuation of the reload option for a non-tradable risk asset under the jump-diffusion processes and Hull-White interest rate. We verify the validity of the actuarial approa...We use an actuarial approach to estimate the valuation of the reload option for a non-tradable risk asset under the jump-diffusion processes and Hull-White interest rate. We verify the validity of the actuarial approach to the European vanilla option for non-tradable assets. The formulas of the actuarial approach to the reload option are derived from the fair premium principle and the obtained results are arbitrage. Numerical experiments are conducted to analyze the effects of different parameters on the results of valuation as well as their differences from those obtained by the no-arbitrage approach. Finally, we give the valuations of the reload options under different parameters.展开更多
文摘AIM:To assess the cost savings of reloading the multiband ligator in endoscopic esophageal variceal ligation (EVL) used on the same patient for subsequent sessions. METHODS:This single centre retrospective descriptive study analysed patients undergoing variceal ligation at a tertiary care centre between 1st January, 2003 and 30th June, 2006. The multiband ligator was reloaded with six hemorrhoidal bands using hemorrhoidal ligator for the second and subsequent sessions. Analysis of cost saving was done for the number of follow-up sessions for the variceal eradication. RESULTS:A total of 261 patients underwent at least one session of endoscopic esophageal variceal ligation between January 2003 and June 2006. Out of 261, 108 patients (males 67) agreed to follow the eradication program and underwent repeated sessions. A total of 304 sessions was performed with 2.81 sessions per patient on average. Thirty-two patients could not complete the programm. In 76 patients (70%), variceal obliteration was achieved. The ratio of the costs for the session with reloaded ligator versus a session with a new ligator was 1:2.37. Among the patients who completed esophageal varices eradication, cost saving with reloaded ligator was 58%. CONCLUSION:EVL using reloaded multiband ligators for the follow-up sessions on patients undergoing variceal eradication is a cost saving procedure. Reloading the ligator thus is recommended especially for developing countries where most of the patients are not health insured.
文摘This research presents an experimental and analytical study of the structural state of the 60/40 brass cartridge case, (BCC) after being fired. The oral section of the BCC has the function of confining the gases of firing by expanding against the chamber and sealing the gases. Firing conditions, namely, high pressure and temperature, 3000 bar and 2727°C, respectively, affect performance properties of the (BCC). These are confining and crack strengths. Experimental study was done on the oral section to address these effects on the structural and mechanical properties of this brass. This alloy is a 60% copper (Cu) and 40% zinc (Zn) alloy and has a two-phase structure, alpha, (α) and beta, (β). Using “before and after” comparison approach;performance properties were tested in cartridge cases prepared before and after firing. These properties are hardness, tensile strength, micro-structural and chemical composition. Comparing the tests’ results, after firing demonstrated considerable degrading in performance properties, micro-structural disorder and a remarkable deficiency in the zinc element in the brass structure. This deficiency affects the percentage of beta phase in the alloy which governs the strength of the brass. According to the required properties before firing, it was found that after firing, the brass cartridge case is not qualified for reloading.
文摘In this work,the modified Ghost Fluid Method is further developed to ap-ply to compressible fluid coupled to deformable structure,where the pressure in the structure or flow can vary from an initial extremely high magnitude(such that the solid medium can be under plastic compression)to a subsequently very low quantity(so that cavitation can occur in the fluid).New techniques are also developed in the definition of the ghost fluid status when the structure is under plastic deformation or when the flow is under cavitation next to the structure.Numerical results show that the improved MGFM for treatment of the fluid-deformable structure coupling works efficiently for all pressure ranges and is capable of simulating cavitation evolution and cavitation re-loading in conjunction with the employment of the isentropic one-fluid cavitation model.
基金Supported by the National Natural Science Foundation of China(No.11571365,11171349)
文摘We use an actuarial approach to estimate the valuation of the reload option for a non-tradable risk asset under the jump-diffusion processes and Hull-White interest rate. We verify the validity of the actuarial approach to the European vanilla option for non-tradable assets. The formulas of the actuarial approach to the reload option are derived from the fair premium principle and the obtained results are arbitrage. Numerical experiments are conducted to analyze the effects of different parameters on the results of valuation as well as their differences from those obtained by the no-arbitrage approach. Finally, we give the valuations of the reload options under different parameters.