Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of c...Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of cancer, and most of the patients in China are diagnosed at advanced stages, resulting in poor prognoses. Effective strategies to reduce the burden of gastric cancer include primary prevention through testing and treatment of Helicobacter pylori(H. pylori) and secondary prevention by screening and early detection. Although many countries have issued management guidelines and consensus reports concerning these strategies, the limited availability of healthcare resources often precludes their widespread implementation. Therefore, assessing the costs, benefits, and harms of population-based intervention measures through health economic evaluation is necessary for informed health policy decisions. Accordingly, we synthesize management approaches from different countries on H. pylori eradication and endoscopic screening, and also summarize recent advancements in health economic evaluations on population-based preventive strategies. The goal of the review is to provide empirical evidence supporting optimal resource allocation, maximizing benefits for the population, and ultimately reducing the burden of gastric cancer.展开更多
The invasive fall armyworm Spodoptera frugiperda(J.E.Smith)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and sum...The invasive fall armyworm Spodoptera frugiperda(J.E.Smith)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and summer.This has resulted in widespread infestations,with significant impacts on maize production in various Asian countries.Previous studies have shown that the invasion of this pest can alter the species relationships of maize pests,but the actual impact on maize pest management is still unclear.This study investigated the changes in maize pest occurrence and pesticide use in the annual breeding areas of S.frugiperda in Yunnan Province and the Guangxi Zhuang Autonomous Region of China during 2017-2021,based on surveys and interviews with small farmers in maize production.The results showed that S.frugiperda has emerged as the dominant species among maize pests after invasion and colonization,replacing traditional pests such as Ostrinia furnacalis,Spodoptera litura,Agrotis ypsilon,and Rhopalosiphum maidis.The variety of pesticides used for maize pest control has changed from chlorpyrifos,lambda-cyhalothrin,and acetamiprid to emamectin benzoate-based pesticides with high effectiveness against S.frugiperda.Furthermore,the frequency of maize pest chemical applications has increased from an average of 5.88 to 7.21 times per season,with the amounts of pesticides used in summer and autumn maize being significantly higher than in winter and spring maize,thereby increasing application costs by more than 35%.The results of this study clarified the impact of S.frugiperda invasion on maize pest community succession and chemical pesticide use in tropical and south subtropical China,thereby providing a baseline for modifying the regional control strategies for maize pests after the invasion of this relatively new pest.展开更多
Objectives: To assess the efficiency in terms of cost-effectiveness (CE) of oral Renalof® treatment versus extracorporeal shockwave lithotripsy (ESWL) in the treatment of kidney stones ≤ 1 cm in Nicaragua. Metho...Objectives: To assess the efficiency in terms of cost-effectiveness (CE) of oral Renalof® treatment versus extracorporeal shockwave lithotripsy (ESWL) in the treatment of kidney stones ≤ 1 cm in Nicaragua. Methods: A cost-effectiveness economic evaluation was carried out based on the results obtained in the randomised, prospective, observational, single-blind, prospective, phase 2 clinical trial. Cost-effectiveness and the incremental cost-effectiveness ratio (ICER) were calculated. Economic data were obtained from the Economics Department of Clínica Senior in Managua, Nicaragua. The monetary cost was expressed in US dollars (USD). Results: Treatment with Renalof® yielded a CE of $1,323.08/% remission, while ESWL was $9,498.54/% remission. The ICER shows that, in order to achieve a high percentage of kidney stone remission with ESWL, an extra $4,734.70 per patient must be invested. Conclusions: The use of Renalof® is shown to be a more cost-effective option than ESWL. It is recommended for the treatment of kidney stones ≤ 1 cm in size.展开更多
Because forecasting a development program during the target selection phase of exploration for coalbed methane (CBM) is impossible, the conventional method that relies on a conceptual (or detailed) development pro...Because forecasting a development program during the target selection phase of exploration for coalbed methane (CBM) is impossible, the conventional method that relies on a conceptual (or detailed) development pro- gram cannot be used during the economic evaluation of CBM resources. Hence, this study focuses on establishing an economic evaluation model based on the characteristics of the target selection phase. The discounted cashflow method is applied to the construction of the model with the assumption that there is a uniform distribution of produc- tion wells. The computational error generated by the assumption is corrected by introducing a correction factor based on the production profile of single CBM wells. The case study demonstrates that the blocks lacking economic value can be screened out, and the most advantageous targets can be found by computing the resource values in the best- and worst-case scenarios. This technique can help to reduce wasted investments and improve the quality of decision-making in selecting targets for exploration.展开更多
The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for...The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for further development and utilization of this classical agricultural technique. The effect of reducing methane emission and the economic benefits of rice-duck ecological system were studied by carrying out a field experiment and by using economic methodology. The daily variation of CH4 emission in late rice paddy field was basically consistent with the daily variation of atmospheric temperature. The highest emission occurred at the full tillering stage of late rice with a rate of 24.1 or 32.2 or 40.5 mg m^-2 h^-1 in no-tillage area with duck and no-tillage area without duck and conventional-tillage area without duck, respectively. The inhibition of methane emission was apparently effective in the rice-duck ecological system during the initial tillering stage and the full tillering stage. Compared to the no-tillage area without duck, methane emission decreased by 2.333 g m^-2. Compared to the conventional-tillage area without duck, methane emission decreased by 4.723 g m^-2. During the production period of late rice, the amount of methane emission in no-tillage area with duck was 3.373 g m^-2 lesser than that of no-tillage area without duck, and 5.59 g m^-2 less than that of conventional-tillage without duck area. The economic significance was analyzed. Farmers adopting the rice-duck ecological system obtained 2 166 and 4 207 RMB yuan ha^-1 more income than those who adopted a no-tillage without duck technique or conventional-tillage without duck technique, respectively. In addition to the reduction of the environmental pollution by methane emission, the farmers who adopted the rice-duck ecological system achieved economic benefits of 5 000 RMB yuan ha^-1, which was 2 206 and 4 274 RMB yuan ha^-1 more than those who adopted a no-tillage without duck technique and a conventional-tillage without duck technique, respectively. The rice-duck ecological system not only increased the economic benefits for farmers, but also reduced methane emission in rice paddy field. A sustainable agricultural production mode was formed.展开更多
Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban China.Methods:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 ye...Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban China.Methods:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 years in a 20-year period.Screening strategies included liquid-based cytology(LBC)every three years,human papillomavirus(HPV)DNA testing every three and five years,respectively,and a combination of HPV DNA testing and LBC(HPV+LBC)every three and five years,respectively.Model outcomes included cumulative incidence over 20 years,cumulative risk of cervical cancer,costs,life year saved(LYS),quality-adjusted life years(QALYs)and benefits.The cost-effectiveness ratios(CERs),incremental cost-effectiveness ratios(ICERs),costutility ratios(CURs),and benefit-cost ratios(BCRs)were used as outcomes in the health economic evaluation analysis.Univariate sensitivity analyses were performed to examine the stability of the results.Results:The cumulative incidence of the five screening strategies ranged from 833.02 to 1,158.07 cases per100,000 females.HPV DNA testing was most effective in reducing the cumulative risk of cervical cancer,saving life years and QALYs and gaining benefits.The CERs of HPV DNA testing every three and five years,and LBC every three years were considered to be very cost-effective if they were below China's GDP per capita.The CERs of HPV+LBC were considered to be cost-effective if they were below three times GDP per capita.The incremental cost-effectiveness analysis showed that HPV DNA testing every three and five years,LBC every three years and HPV+LBC every five years were dominant strategies.Conclusions:The findings of this study indicated that HPV DNA testing every five years or LBC every three years should be recommended in urban China.展开更多
This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristic...This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption (PSA), chemical absorption (CA), and membrane absorption (MA). Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.展开更多
Energy storage system is an important means to improve the flexibility and safety of traditional power system,but it has the problem of high cost and unclear value recovery path.In this paper,the typical application s...Energy storage system is an important means to improve the flexibility and safety of traditional power system,but it has the problem of high cost and unclear value recovery path.In this paper,the typical application scenarios of energy storage system are summarized and analyzed from the perspectives of user side,power grid side and power generation side.Based on the typical application scenarios,the economic benefit assessment framework of energy storage system including value,time and efficiency indicators is proposed.Typical battery energy storage projects are selected for economic benefit calculation according to different scenarios,and key factors are selected for sensitivity analysis.Finally,the key factors affecting economic benefit of the energy storage system are analyzed.展开更多
The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This stu...The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.展开更多
Objective To evaluate the economy of detecting gastric cancer by electronic gastroscope in Chinese natural population of different ages and genders.Methods A Markov model was constructed for the population,including b...Objective To evaluate the economy of detecting gastric cancer by electronic gastroscope in Chinese natural population of different ages and genders.Methods A Markov model was constructed for the population,including both men and women of different ages.The model cycle was one year and the simulation time was 60 years.The cost-effectiveness of electronic gastroscopy in detecting gastric cancer of general population in China was analyzed from the perspective of the whole society,and the stability of the results was verified by sensitivity analysis.Results and Conclusion For the general population,the incremental cost-effectiveness ratio(ICER)of gastric cancer screening from the age of 50 is 50143 yuan/QALY(quality-adjusted life-year),which is less than two times of per capita gross domestic product(GDP)compared with the screening from the age of 55.For men who start gastric cancer screening at the age of 50,the ICER is 38525 yuan/QALY,which is less than two times of per capita GDP,and it is economical.For women who start the screening from the age of 55,the ICER is 47814 yuan/QALY,which is less than two times of per capita GDP,so it is economical.The results of sensitivity analysis are consistent with the conclusions of basic analysis,and the results of basic analysis are stable.For the general population,it is more economical to start gastric cancer screening from the age of 50,while for men and women,it is more economical to start gastric cancer screening from the age of 50 and 55,respectively.展开更多
Hydraulic fracturing is among the approaches used to optimize production from a gas condensate reservoir. A detailed economic analysis is required to evaluate the profitability and feasibility of hydraulic fracturing ...Hydraulic fracturing is among the approaches used to optimize production from a gas condensate reservoir. A detailed economic analysis is required to evaluate the profitability and feasibility of hydraulic fracturing as an optimization option in a gas condensate reservoir operating below dewpoint. The objective of this research is to evaluate the economic benefits derivable from the use of hydraulic fracturing to improve gas and liquid recovery from a gas condensate reservoir operating below dewpoint. This research considers the use of four profit indicators to ascertain the profitability of hydraulic fracturing in a gas condensate reservoir operating below dewpoint by increasing the fracture halflength, fracture width and fracture permeability. The production data of the reservoir was obtained and the economic calculations done on excel spreadsheet and plots generated. The four profit indicators considered in the research are Net Present Value, Payout, Discounted Cash Flow Rate of Return and Profit per Dollar Invested. The economic justification was done by carrying out a comparative economic analysis from the result obtained when the reservoir of study was unfractured with that obtained when the reservoir was fractured at various fracture parameters. The economic analysis was done considering a royalty and tax rate of 18.5% and 30% respectively and a gas price of $2/MSCF and condensate price of $30/bbl. This is done so as to find out if the additional cost of hydraulic fracturing can be offset by the recovery from the reservoir when its pressure declined below dewpoint. The result obtained showed that the additional recovery due to hydraulic fracturing by increasing the fracture halflength, fracture width and fracture permeability was not enough to justify the application of hydraulic fracturing when the reservoir pressure declined below dewpoint.展开更多
Objective To systematically review the published clinical and economic research on liposomal irinotecan in combination with 5-FU/LV for metastatic pancreatic ductal adenocarcinoma(mPDAC)at home and abroad.Methods PubM...Objective To systematically review the published clinical and economic research on liposomal irinotecan in combination with 5-FU/LV for metastatic pancreatic ductal adenocarcinoma(mPDAC)at home and abroad.Methods PubMed,Cochrane Library,Embase,CBM,CNKI,Wan Fang data,CRD database and health technology assessment official websites were searched to collect clinical and economic studies on liposomal irinotecan for mPDAC.Results and Conclusion Nine clinical studies and four economic studies were included.The result of clinical studies showed that liposomal irinotecan in combination with 5-FU/LV could extend survival with good drug compliance in patients with mPDAC who progressed on prior gemcitabine-based therapy.This agent represented a new treatment option for second-line chemotherapy in these patients.The results of the economic evaluations failed to reach a consistent conclusion due to different economic levels in various countries.展开更多
目的对经外周置入中心静脉导管(peripherally inserted central catheter,PICC)置管、维护及拔管的单项操作成本进行核算,为制定合理的操作收费价格提供依据。方法通过横断面调查,采用项目成本阶梯分摊法,于2019年1—5月在复旦大学附属...目的对经外周置入中心静脉导管(peripherally inserted central catheter,PICC)置管、维护及拔管的单项操作成本进行核算,为制定合理的操作收费价格提供依据。方法通过横断面调查,采用项目成本阶梯分摊法,于2019年1—5月在复旦大学附属肿瘤医院血管通路门诊测算PICC各单项操作人力成本、设备折旧费及未单独计价材料费,测算直接成本,并通过分摊测算间接成本,最后测算PICC置管、维护及拔管的单项操作成本。结果PICC置管、维护及拔管的各单项操作实际成本分别为(157.03±4.73)元、(33.66±3.04)元、(32.38±3.11)元,与上海市医疗机构对PICC各项操作的收费标准(分别为150元、30元、30元)基本相符。结论建议将PICC维护及拔管的操作收费纳入收费标准中,促进PICC输液技术的可持续发展并确保护理服务的持续供给。展开更多
This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically deter...This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically determine the weight coefficients among the multiindices and also can obtain the exact and reliable evaluation results without subjectivity.展开更多
Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs.Most studies that have assessed the co...Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs.Most studies that have assessed the cost of PC suffer from poor quality and a lack of transparency and consistency.The payment system in place often rewards the volume of services provided rather than the quality of patients’clinical outcomes.Without a thorough registration of PC,the economic costs involved cannot be determined.An accurate,reliable appraisal would help identify areas for investment in order to reduce the incidence of PC,improve surgical results,and bring down the economic costs.This article describes how to quantify and classify PC using the Clavien-Dindo classification and the comprehensive complication index,discusses the perspectives from which economic evaluations are performed and the minimum postoperative follow-up established,and makes various recommendations.The availability of accurate and impartially audited data on PC will help reduce their incidence and bring down costs.Patients,the health authorities,and society as a whole are sure to benefit.展开更多
In this work,a model of hydrogen production by double chemical looping is introduced.The efficiency benefit obtained was investigated.The chemical looping hydrogen generation unit is connected in series to the downstr...In this work,a model of hydrogen production by double chemical looping is introduced.The efficiency benefit obtained was investigated.The chemical looping hydrogen generation unit is connected in series to the downstream of a chemical looping gasification unit as an additional system for 100 MWh coal gasification,with the function of supplementary combustion to produce hydrogen.Using Aspen Plus software for process simulation,the production of H_(2) and N_(2) in the series system is higher than that in the independent Chemical looping gasification and Chemical looping hydrogen generation systems,and the production of hydrogen is approximately 25.63%and 12.90%higher,respectively;The study found that when the gasification temperature is 900C,steam-carbon ratio is 0.84 and oxygen-carbon ratio is 1.5,the hydrogen production rate of the system was the maximum.At the same time,through heat exchange between logistics,high-pressure steam at 8.010×10^(4) kg·h^(-1) and medium-pressure steam at 1.101×10^(4) kg·h^(-1) are generated,and utility consumption is reduced by 61.58%,with utility costs decreasing by 48.69%.An economic estimation study found that the production cost of ammonia is 108.66 USD(t NH_(3))^(-1).Finally,cost of equipment is the main factors influencing ammonia production cost were proposed by sensitivity analysis.展开更多
This paper proposes a comprehensive framework for estimating the regional rooftop photovoltaic(PV)potential.The required rooftop information is extracted from Gao Fen-7 satellite images.In particular,the rooftop area ...This paper proposes a comprehensive framework for estimating the regional rooftop photovoltaic(PV)potential.The required rooftop information is extracted from Gao Fen-7 satellite images.In particular,the rooftop area is obtained using a semantic segmentation network.The azimuth and inclination angles are calculated based on the digital surface model.In addition,to improve the accuracy of the economic evaluation,buildings are divided into commercial and industrial buildings and residential buildings.Based on the difference in the roof inclination,the rooftops can be divided into flat roofs,on which the PV panels are installed with the optimal inclination angle,and sloped rooftops,on which the PV panels are installed in a lay-flat manner.The solar irradiation on the plane-of-array is calculated using the isotropic sky translocation model.Then,the available installed capacity and generation potential of the rooftop PV is obtained.Finally,the net present value,dynamic payback period,and internal rate of return are used to evaluate the economic efficiency of the rooftop PV project.The proposed framework is applied in the Da Xing district of Beijing,China,with a total area of 546.84 km^(2).The results show that the rooftop area and available installed capacity of PV are 25.63 km^(2)and 1487.45 MWp,respectively.The annual rooftop PV generation potential is 2832.23 GWh,with significant economic returns.展开更多
The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1...The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1980-2014 across China.The results indicated that the ESV of the paddy field in China showed an upward trend during this period.The share of ESV on CO_(2)sequestration was the highest,followed by ESV on temperature cooling and greenhouse gas(GHG)emission.The yield-scaled ESVs of ZonesⅡ(southern rice-upland crops rotation regions)andⅢ(southern double rice production regions)were similar and significantly higher than the ESVs of ZonesⅠ(northeastern single rice production regions)and IV(Southwest rice-upland crops rotation regions).Between 1980 and 2014,the ESV of each region increased to varying degrees,except for the ESVs of Guangxi,Zhejiang,Fujian,and Guangdong.Such effects suggest the existence of a significant spatial-temporal variation in the total amount,structure,and density of ESV of paddy fields in China,which can further guide the development of future options for the adaptation of healthy rice production in China.展开更多
LHD's are expensive vehicles; therefore, it is important to accurately define the financial consequences associated with the investment of purchasing the mining equipment. This study concentrates on longterm incre...LHD's are expensive vehicles; therefore, it is important to accurately define the financial consequences associated with the investment of purchasing the mining equipment. This study concentrates on longterm incremental and sensitivity analysis to determine whether it is feasible to incorporate current battery technology into these machines. When revenue was taken into account, decreasing the amount of haulage in battery operated equipment by 5% or 200 kg per h amounts to a $4.0 × 10~4 loss of profit per year. On average it was found that using battery operated equipment generated $9.5 × 10~4 more in income annually, reducing the payback period from seven to two years to pay back the additional $1.0 × 10~5 investment of buying battery powered equipment over cheaper diesel equipment. Due to the estimated 5% increase in capital, it was observed that electric vehicles must possess a lifetime that is a minimum of one year longer than that of diesel equipment.展开更多
Key parameters and evaluation methods of shale gas show that it is not possible to guarantee the commercial and economic development of shale gas by sorting out geological sweet spots only according to technical indic...Key parameters and evaluation methods of shale gas show that it is not possible to guarantee the commercial and economic development of shale gas by sorting out geological sweet spots only according to technical indicators.A research method combining technical indicators including total organic carbon content and vitrinite reflectance with economic indicators including internal rate of return and investment payback period is proposed to screen the best technological and economic development sweet spots in undeveloped areas.This method was used to evaluate the best technological and economic development sweet spots in Cretaceous shale gas reservoirs S_(1) and S_(2) of Lurestan area,Iran.Twenty-one geologic sweet spots were picked out based on effective reservoir thickness,vitrinite reflectance and gas content.Based on analogy method,the pressure gradient,clay mineral content,buried depth and other parameters were taken as comparative indicators,the Eagle Ford shale as comparison object,recovery factor and production curve were extracted to estimate the technologically recoverable reserves of the study area.On this basis,the economic indexes such as internal rate of return and investment payback period were used to evaluate the economy of the geological sweet spots.In the case of P_(10) distribution,the total technologically recoverable reserves and economically recoverable reserves are 7875×10^(8)m^(3) and 4306×10^(8)m^(3) respectively,11 geological sweet spots have commercial development value,among which,No.1 sweet spot has the highest value,with a net present value of 35×10^(8) USD.展开更多
基金supported in part by the Beijing Hospitals Authority Clinical Medicine Development of Special Funding Support (No. ZLRK202325)a grant from National Key R&D Program of China (No. 2018YFC 1313105)。
文摘Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of cancer, and most of the patients in China are diagnosed at advanced stages, resulting in poor prognoses. Effective strategies to reduce the burden of gastric cancer include primary prevention through testing and treatment of Helicobacter pylori(H. pylori) and secondary prevention by screening and early detection. Although many countries have issued management guidelines and consensus reports concerning these strategies, the limited availability of healthcare resources often precludes their widespread implementation. Therefore, assessing the costs, benefits, and harms of population-based intervention measures through health economic evaluation is necessary for informed health policy decisions. Accordingly, we synthesize management approaches from different countries on H. pylori eradication and endoscopic screening, and also summarize recent advancements in health economic evaluations on population-based preventive strategies. The goal of the review is to provide empirical evidence supporting optimal resource allocation, maximizing benefits for the population, and ultimately reducing the burden of gastric cancer.
基金supported by the Lingnan Modern Agriculture Project China(NT2021003)the earmarked fund for China Agricultural Research System(CARS-02)。
文摘The invasive fall armyworm Spodoptera frugiperda(J.E.Smith)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and summer.This has resulted in widespread infestations,with significant impacts on maize production in various Asian countries.Previous studies have shown that the invasion of this pest can alter the species relationships of maize pests,but the actual impact on maize pest management is still unclear.This study investigated the changes in maize pest occurrence and pesticide use in the annual breeding areas of S.frugiperda in Yunnan Province and the Guangxi Zhuang Autonomous Region of China during 2017-2021,based on surveys and interviews with small farmers in maize production.The results showed that S.frugiperda has emerged as the dominant species among maize pests after invasion and colonization,replacing traditional pests such as Ostrinia furnacalis,Spodoptera litura,Agrotis ypsilon,and Rhopalosiphum maidis.The variety of pesticides used for maize pest control has changed from chlorpyrifos,lambda-cyhalothrin,and acetamiprid to emamectin benzoate-based pesticides with high effectiveness against S.frugiperda.Furthermore,the frequency of maize pest chemical applications has increased from an average of 5.88 to 7.21 times per season,with the amounts of pesticides used in summer and autumn maize being significantly higher than in winter and spring maize,thereby increasing application costs by more than 35%.The results of this study clarified the impact of S.frugiperda invasion on maize pest community succession and chemical pesticide use in tropical and south subtropical China,thereby providing a baseline for modifying the regional control strategies for maize pests after the invasion of this relatively new pest.
文摘Objectives: To assess the efficiency in terms of cost-effectiveness (CE) of oral Renalof® treatment versus extracorporeal shockwave lithotripsy (ESWL) in the treatment of kidney stones ≤ 1 cm in Nicaragua. Methods: A cost-effectiveness economic evaluation was carried out based on the results obtained in the randomised, prospective, observational, single-blind, prospective, phase 2 clinical trial. Cost-effectiveness and the incremental cost-effectiveness ratio (ICER) were calculated. Economic data were obtained from the Economics Department of Clínica Senior in Managua, Nicaragua. The monetary cost was expressed in US dollars (USD). Results: Treatment with Renalof® yielded a CE of $1,323.08/% remission, while ESWL was $9,498.54/% remission. The ICER shows that, in order to achieve a high percentage of kidney stone remission with ESWL, an extra $4,734.70 per patient must be invested. Conclusions: The use of Renalof® is shown to be a more cost-effective option than ESWL. It is recommended for the treatment of kidney stones ≤ 1 cm in size.
基金funded by the Beijing Natural Science Foundation (9144033)the National Social Science Fund for Major Projects (11&ZD164)
文摘Because forecasting a development program during the target selection phase of exploration for coalbed methane (CBM) is impossible, the conventional method that relies on a conceptual (or detailed) development pro- gram cannot be used during the economic evaluation of CBM resources. Hence, this study focuses on establishing an economic evaluation model based on the characteristics of the target selection phase. The discounted cashflow method is applied to the construction of the model with the assumption that there is a uniform distribution of produc- tion wells. The computational error generated by the assumption is corrected by introducing a correction factor based on the production profile of single CBM wells. The case study demonstrates that the blocks lacking economic value can be screened out, and the most advantageous targets can be found by computing the resource values in the best- and worst-case scenarios. This technique can help to reduce wasted investments and improve the quality of decision-making in selecting targets for exploration.
文摘The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for further development and utilization of this classical agricultural technique. The effect of reducing methane emission and the economic benefits of rice-duck ecological system were studied by carrying out a field experiment and by using economic methodology. The daily variation of CH4 emission in late rice paddy field was basically consistent with the daily variation of atmospheric temperature. The highest emission occurred at the full tillering stage of late rice with a rate of 24.1 or 32.2 or 40.5 mg m^-2 h^-1 in no-tillage area with duck and no-tillage area without duck and conventional-tillage area without duck, respectively. The inhibition of methane emission was apparently effective in the rice-duck ecological system during the initial tillering stage and the full tillering stage. Compared to the no-tillage area without duck, methane emission decreased by 2.333 g m^-2. Compared to the conventional-tillage area without duck, methane emission decreased by 4.723 g m^-2. During the production period of late rice, the amount of methane emission in no-tillage area with duck was 3.373 g m^-2 lesser than that of no-tillage area without duck, and 5.59 g m^-2 less than that of conventional-tillage without duck area. The economic significance was analyzed. Farmers adopting the rice-duck ecological system obtained 2 166 and 4 207 RMB yuan ha^-1 more income than those who adopted a no-tillage without duck technique or conventional-tillage without duck technique, respectively. In addition to the reduction of the environmental pollution by methane emission, the farmers who adopted the rice-duck ecological system achieved economic benefits of 5 000 RMB yuan ha^-1, which was 2 206 and 4 274 RMB yuan ha^-1 more than those who adopted a no-tillage without duck technique and a conventional-tillage without duck technique, respectively. The rice-duck ecological system not only increased the economic benefits for farmers, but also reduced methane emission in rice paddy field. A sustainable agricultural production mode was formed.
基金supported by the National Health Commission of the People’s Republic of China (formerly the Health and Family Planning Commission) of China (No. 201502004)
文摘Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban China.Methods:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 years in a 20-year period.Screening strategies included liquid-based cytology(LBC)every three years,human papillomavirus(HPV)DNA testing every three and five years,respectively,and a combination of HPV DNA testing and LBC(HPV+LBC)every three and five years,respectively.Model outcomes included cumulative incidence over 20 years,cumulative risk of cervical cancer,costs,life year saved(LYS),quality-adjusted life years(QALYs)and benefits.The cost-effectiveness ratios(CERs),incremental cost-effectiveness ratios(ICERs),costutility ratios(CURs),and benefit-cost ratios(BCRs)were used as outcomes in the health economic evaluation analysis.Univariate sensitivity analyses were performed to examine the stability of the results.Results:The cumulative incidence of the five screening strategies ranged from 833.02 to 1,158.07 cases per100,000 females.HPV DNA testing was most effective in reducing the cumulative risk of cervical cancer,saving life years and QALYs and gaining benefits.The CERs of HPV DNA testing every three and five years,and LBC every three years were considered to be very cost-effective if they were below China's GDP per capita.The CERs of HPV+LBC were considered to be cost-effective if they were below three times GDP per capita.The incremental cost-effectiveness analysis showed that HPV DNA testing every three and five years,LBC every three years and HPV+LBC every five years were dominant strategies.Conclusions:The findings of this study indicated that HPV DNA testing every five years or LBC every three years should be recommended in urban China.
基金the China University of Petroleum Foundationthe Research Institute of Safety and Environment TechnologyChina National Petroleum Corporation
文摘This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption (PSA), chemical absorption (CA), and membrane absorption (MA). Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.
基金supported by State Grid Zhejiang Electric Power Co.,Ltd.(Project of Research on interactive operation control technology and business model of 5G base station energy storage and power grid(B311JX210006)).
文摘Energy storage system is an important means to improve the flexibility and safety of traditional power system,but it has the problem of high cost and unclear value recovery path.In this paper,the typical application scenarios of energy storage system are summarized and analyzed from the perspectives of user side,power grid side and power generation side.Based on the typical application scenarios,the economic benefit assessment framework of energy storage system including value,time and efficiency indicators is proposed.Typical battery energy storage projects are selected for economic benefit calculation according to different scenarios,and key factors are selected for sensitivity analysis.Finally,the key factors affecting economic benefit of the energy storage system are analyzed.
文摘The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.
文摘Objective To evaluate the economy of detecting gastric cancer by electronic gastroscope in Chinese natural population of different ages and genders.Methods A Markov model was constructed for the population,including both men and women of different ages.The model cycle was one year and the simulation time was 60 years.The cost-effectiveness of electronic gastroscopy in detecting gastric cancer of general population in China was analyzed from the perspective of the whole society,and the stability of the results was verified by sensitivity analysis.Results and Conclusion For the general population,the incremental cost-effectiveness ratio(ICER)of gastric cancer screening from the age of 50 is 50143 yuan/QALY(quality-adjusted life-year),which is less than two times of per capita gross domestic product(GDP)compared with the screening from the age of 55.For men who start gastric cancer screening at the age of 50,the ICER is 38525 yuan/QALY,which is less than two times of per capita GDP,and it is economical.For women who start the screening from the age of 55,the ICER is 47814 yuan/QALY,which is less than two times of per capita GDP,so it is economical.The results of sensitivity analysis are consistent with the conclusions of basic analysis,and the results of basic analysis are stable.For the general population,it is more economical to start gastric cancer screening from the age of 50,while for men and women,it is more economical to start gastric cancer screening from the age of 50 and 55,respectively.
文摘Hydraulic fracturing is among the approaches used to optimize production from a gas condensate reservoir. A detailed economic analysis is required to evaluate the profitability and feasibility of hydraulic fracturing as an optimization option in a gas condensate reservoir operating below dewpoint. The objective of this research is to evaluate the economic benefits derivable from the use of hydraulic fracturing to improve gas and liquid recovery from a gas condensate reservoir operating below dewpoint. This research considers the use of four profit indicators to ascertain the profitability of hydraulic fracturing in a gas condensate reservoir operating below dewpoint by increasing the fracture halflength, fracture width and fracture permeability. The production data of the reservoir was obtained and the economic calculations done on excel spreadsheet and plots generated. The four profit indicators considered in the research are Net Present Value, Payout, Discounted Cash Flow Rate of Return and Profit per Dollar Invested. The economic justification was done by carrying out a comparative economic analysis from the result obtained when the reservoir of study was unfractured with that obtained when the reservoir was fractured at various fracture parameters. The economic analysis was done considering a royalty and tax rate of 18.5% and 30% respectively and a gas price of $2/MSCF and condensate price of $30/bbl. This is done so as to find out if the additional cost of hydraulic fracturing can be offset by the recovery from the reservoir when its pressure declined below dewpoint. The result obtained showed that the additional recovery due to hydraulic fracturing by increasing the fracture halflength, fracture width and fracture permeability was not enough to justify the application of hydraulic fracturing when the reservoir pressure declined below dewpoint.
文摘Objective To systematically review the published clinical and economic research on liposomal irinotecan in combination with 5-FU/LV for metastatic pancreatic ductal adenocarcinoma(mPDAC)at home and abroad.Methods PubMed,Cochrane Library,Embase,CBM,CNKI,Wan Fang data,CRD database and health technology assessment official websites were searched to collect clinical and economic studies on liposomal irinotecan for mPDAC.Results and Conclusion Nine clinical studies and four economic studies were included.The result of clinical studies showed that liposomal irinotecan in combination with 5-FU/LV could extend survival with good drug compliance in patients with mPDAC who progressed on prior gemcitabine-based therapy.This agent represented a new treatment option for second-line chemotherapy in these patients.The results of the economic evaluations failed to reach a consistent conclusion due to different economic levels in various countries.
文摘目的对经外周置入中心静脉导管(peripherally inserted central catheter,PICC)置管、维护及拔管的单项操作成本进行核算,为制定合理的操作收费价格提供依据。方法通过横断面调查,采用项目成本阶梯分摊法,于2019年1—5月在复旦大学附属肿瘤医院血管通路门诊测算PICC各单项操作人力成本、设备折旧费及未单独计价材料费,测算直接成本,并通过分摊测算间接成本,最后测算PICC置管、维护及拔管的单项操作成本。结果PICC置管、维护及拔管的各单项操作实际成本分别为(157.03±4.73)元、(33.66±3.04)元、(32.38±3.11)元,与上海市医疗机构对PICC各项操作的收费标准(分别为150元、30元、30元)基本相符。结论建议将PICC维护及拔管的操作收费纳入收费标准中,促进PICC输液技术的可持续发展并确保护理服务的持续供给。
文摘This paper takes the synthesizing evaluation about industrial economic benefits by examples and proposes a new method named maximizing deviation method for multiindices decision. The new method can automatically determine the weight coefficients among the multiindices and also can obtain the exact and reliable evaluation results without subjectivity.
文摘Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs.Most studies that have assessed the cost of PC suffer from poor quality and a lack of transparency and consistency.The payment system in place often rewards the volume of services provided rather than the quality of patients’clinical outcomes.Without a thorough registration of PC,the economic costs involved cannot be determined.An accurate,reliable appraisal would help identify areas for investment in order to reduce the incidence of PC,improve surgical results,and bring down the economic costs.This article describes how to quantify and classify PC using the Clavien-Dindo classification and the comprehensive complication index,discusses the perspectives from which economic evaluations are performed and the minimum postoperative follow-up established,and makes various recommendations.The availability of accurate and impartially audited data on PC will help reduce their incidence and bring down costs.Patients,the health authorities,and society as a whole are sure to benefit.
基金supported by the National Key Research and Development Program of China(2018YFB0605401)the National Key Research and Development Program Project of Ningxia(2018BEE03009)+1 种基金the National Natural Science Foundation of China(21868025)Major Program of Key Research and Development Program of Ningxia Province of China(2018BCE01002).
文摘In this work,a model of hydrogen production by double chemical looping is introduced.The efficiency benefit obtained was investigated.The chemical looping hydrogen generation unit is connected in series to the downstream of a chemical looping gasification unit as an additional system for 100 MWh coal gasification,with the function of supplementary combustion to produce hydrogen.Using Aspen Plus software for process simulation,the production of H_(2) and N_(2) in the series system is higher than that in the independent Chemical looping gasification and Chemical looping hydrogen generation systems,and the production of hydrogen is approximately 25.63%and 12.90%higher,respectively;The study found that when the gasification temperature is 900C,steam-carbon ratio is 0.84 and oxygen-carbon ratio is 1.5,the hydrogen production rate of the system was the maximum.At the same time,through heat exchange between logistics,high-pressure steam at 8.010×10^(4) kg·h^(-1) and medium-pressure steam at 1.101×10^(4) kg·h^(-1) are generated,and utility consumption is reduced by 61.58%,with utility costs decreasing by 48.69%.An economic estimation study found that the production cost of ammonia is 108.66 USD(t NH_(3))^(-1).Finally,cost of equipment is the main factors influencing ammonia production cost were proposed by sensitivity analysis.
基金supported by the Global Energy Interconnection Group Co.,Ltd.,Science and Technology Project(SGGEIG00JYJS2100032)。
文摘This paper proposes a comprehensive framework for estimating the regional rooftop photovoltaic(PV)potential.The required rooftop information is extracted from Gao Fen-7 satellite images.In particular,the rooftop area is obtained using a semantic segmentation network.The azimuth and inclination angles are calculated based on the digital surface model.In addition,to improve the accuracy of the economic evaluation,buildings are divided into commercial and industrial buildings and residential buildings.Based on the difference in the roof inclination,the rooftops can be divided into flat roofs,on which the PV panels are installed with the optimal inclination angle,and sloped rooftops,on which the PV panels are installed in a lay-flat manner.The solar irradiation on the plane-of-array is calculated using the isotropic sky translocation model.Then,the available installed capacity and generation potential of the rooftop PV is obtained.Finally,the net present value,dynamic payback period,and internal rate of return are used to evaluate the economic efficiency of the rooftop PV project.The proposed framework is applied in the Da Xing district of Beijing,China,with a total area of 546.84 km^(2).The results show that the rooftop area and available installed capacity of PV are 25.63 km^(2)and 1487.45 MWp,respectively.The annual rooftop PV generation potential is 2832.23 GWh,with significant economic returns.
基金supported by the Natural Science Foundation of Zhejiang,China(Q21C130007)the National Key Research and Development Program of China(2016YFD0300210)。
文摘The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1980-2014 across China.The results indicated that the ESV of the paddy field in China showed an upward trend during this period.The share of ESV on CO_(2)sequestration was the highest,followed by ESV on temperature cooling and greenhouse gas(GHG)emission.The yield-scaled ESVs of ZonesⅡ(southern rice-upland crops rotation regions)andⅢ(southern double rice production regions)were similar and significantly higher than the ESVs of ZonesⅠ(northeastern single rice production regions)and IV(Southwest rice-upland crops rotation regions).Between 1980 and 2014,the ESV of each region increased to varying degrees,except for the ESVs of Guangxi,Zhejiang,Fujian,and Guangdong.Such effects suggest the existence of a significant spatial-temporal variation in the total amount,structure,and density of ESV of paddy fields in China,which can further guide the development of future options for the adaptation of healthy rice production in China.
文摘LHD's are expensive vehicles; therefore, it is important to accurately define the financial consequences associated with the investment of purchasing the mining equipment. This study concentrates on longterm incremental and sensitivity analysis to determine whether it is feasible to incorporate current battery technology into these machines. When revenue was taken into account, decreasing the amount of haulage in battery operated equipment by 5% or 200 kg per h amounts to a $4.0 × 10~4 loss of profit per year. On average it was found that using battery operated equipment generated $9.5 × 10~4 more in income annually, reducing the payback period from seven to two years to pay back the additional $1.0 × 10~5 investment of buying battery powered equipment over cheaper diesel equipment. Due to the estimated 5% increase in capital, it was observed that electric vehicles must possess a lifetime that is a minimum of one year longer than that of diesel equipment.
文摘Key parameters and evaluation methods of shale gas show that it is not possible to guarantee the commercial and economic development of shale gas by sorting out geological sweet spots only according to technical indicators.A research method combining technical indicators including total organic carbon content and vitrinite reflectance with economic indicators including internal rate of return and investment payback period is proposed to screen the best technological and economic development sweet spots in undeveloped areas.This method was used to evaluate the best technological and economic development sweet spots in Cretaceous shale gas reservoirs S_(1) and S_(2) of Lurestan area,Iran.Twenty-one geologic sweet spots were picked out based on effective reservoir thickness,vitrinite reflectance and gas content.Based on analogy method,the pressure gradient,clay mineral content,buried depth and other parameters were taken as comparative indicators,the Eagle Ford shale as comparison object,recovery factor and production curve were extracted to estimate the technologically recoverable reserves of the study area.On this basis,the economic indexes such as internal rate of return and investment payback period were used to evaluate the economy of the geological sweet spots.In the case of P_(10) distribution,the total technologically recoverable reserves and economically recoverable reserves are 7875×10^(8)m^(3) and 4306×10^(8)m^(3) respectively,11 geological sweet spots have commercial development value,among which,No.1 sweet spot has the highest value,with a net present value of 35×10^(8) USD.