Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing...Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing of large capital investment towards research and development of sustainable alternative energy sources. One of the most promising and abundant of these sources is hydrogen. Firstly, the use of current fossil fuels is. discussed focusing on the emissions and economic sides to emphasize the need for a new, cleaner and renewable fuel with particular reference to hydrogen as a suitable possible alternative. Hydrogen properties, production and storage methods are then reviewed along with its suitability from the economical point of view. Finally, a cost analysis for the use of hydrogen in internal combustion engines is carried out to illustrate the benefits of its use as a replacement for diesel. The outcome of this cost analysis shows that 98% of the capital expenditure is consumed by the equipment, and 68.3% of the total cost of the equipment is spent on the solar photovoltaic cells. The hydrogen plant is classified as a large investment project because of its high initial cost which is about 1 billion US$; but this is justified because hydrogen is produced in a totally green way. When hydrogen is used as a fuel, no harmful emissions are obtained.展开更多
AIM:To compare reverse-total shoulder arthroplasty(RSA)cost-effectiveness with total hip arthroplasty cost-effectiveness.METHODS:This study used a stochastic model and decision-making algorithm to compare the costeffe...AIM:To compare reverse-total shoulder arthroplasty(RSA)cost-effectiveness with total hip arthroplasty cost-effectiveness.METHODS:This study used a stochastic model and decision-making algorithm to compare the costeffectiveness of RSA and total hip arthroplasty.Fifteen patients underwent pre-operative,and 3,6,and 12 mo post-operative clinical examinations and Short Form-36 Health Survey completion.Short form-36 Health Survey subscale scores were converted to EuroQ ual Group Five Dimension Health Outcome scores and compared with historical data from age-matched patients who had undergone total hip arthroplasty.Quality-adjusted life year(QALY)improvements based on life expectancies were calculated.RESULTS:The cost/QALY was $3900 for total hip arthroplasty and $11100 for RSA.After adjusting the model to only include shoulder-specific physical function subscale items,the RSA QALY improved to 2.8years,and its cost/QALY decreased to $8100.CONCLUSION:Based on industry accepted standards,cost/QALY estimates supported both RSA and total hip arthroplasty cost-effectiveness.Although total hip arthroplasty remains the quality of life improvement "gold standard" among arthroplasty procedures,cost/QALY estimates identified in this study support the growing use of RSA to improve patient quality of life.展开更多
文摘Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing of large capital investment towards research and development of sustainable alternative energy sources. One of the most promising and abundant of these sources is hydrogen. Firstly, the use of current fossil fuels is. discussed focusing on the emissions and economic sides to emphasize the need for a new, cleaner and renewable fuel with particular reference to hydrogen as a suitable possible alternative. Hydrogen properties, production and storage methods are then reviewed along with its suitability from the economical point of view. Finally, a cost analysis for the use of hydrogen in internal combustion engines is carried out to illustrate the benefits of its use as a replacement for diesel. The outcome of this cost analysis shows that 98% of the capital expenditure is consumed by the equipment, and 68.3% of the total cost of the equipment is spent on the solar photovoltaic cells. The hydrogen plant is classified as a large investment project because of its high initial cost which is about 1 billion US$; but this is justified because hydrogen is produced in a totally green way. When hydrogen is used as a fuel, no harmful emissions are obtained.
文摘AIM:To compare reverse-total shoulder arthroplasty(RSA)cost-effectiveness with total hip arthroplasty cost-effectiveness.METHODS:This study used a stochastic model and decision-making algorithm to compare the costeffectiveness of RSA and total hip arthroplasty.Fifteen patients underwent pre-operative,and 3,6,and 12 mo post-operative clinical examinations and Short Form-36 Health Survey completion.Short form-36 Health Survey subscale scores were converted to EuroQ ual Group Five Dimension Health Outcome scores and compared with historical data from age-matched patients who had undergone total hip arthroplasty.Quality-adjusted life year(QALY)improvements based on life expectancies were calculated.RESULTS:The cost/QALY was $3900 for total hip arthroplasty and $11100 for RSA.After adjusting the model to only include shoulder-specific physical function subscale items,the RSA QALY improved to 2.8years,and its cost/QALY decreased to $8100.CONCLUSION:Based on industry accepted standards,cost/QALY estimates supported both RSA and total hip arthroplasty cost-effectiveness.Although total hip arthroplasty remains the quality of life improvement "gold standard" among arthroplasty procedures,cost/QALY estimates identified in this study support the growing use of RSA to improve patient quality of life.
