AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quanti...AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quantitate the reduction of mean IOP and glaucoma medications for each surgical intervention in childhood glaucoma. A US perspective was adopted, using Medicare allowable costs to calculate cost/mm Hg IOP reduction($/mm Hg) at 1y postoperatively.RESULTS: At 1y postoperatively, the cost/mm Hg IOP reduction was $226/mm Hg for microcatheter-assisted circumferential trabeculotomy, $284/mm Hg for cyclophotocoagulation, $288/mm Hg for conventional ab-externo trabeculotomy, $338/mm Hg for Ahmed glaucoma valve, $350/mm Hg for Baerveldt glaucoma implant, $351/mm Hg for goniotomy, and $400/mm Hg for trabeculectomy.CONCLUSION: Microcatheter-assisted circumferential trabeculotomy is the most cost-efficient surgical method to lower IOP in childhood glaucoma, while trabeculectomy is the least cost-efficient surgical method.展开更多
For probabilistic programs,there is some work for qualitative and quantitative analysis about expec-tation or mean,such as expected termination time,and expected cost analysis.However,another non-trivial issue is abou...For probabilistic programs,there is some work for qualitative and quantitative analysis about expec-tation or mean,such as expected termination time,and expected cost analysis.However,another non-trivial issue is about tail bounds(i.e.,upper bounds of tail probabilities),which can provide high-probability guarantees to extreme events.In this work,we focus on the problem of tail-bound cost analysis over nondeterministic proba-bilistic programs,which aims to automatically obtain the tail bound of resource usages over such programs.To achieve this goal,we present a novel approach,combined with a suitable concentration inequality,to derive the tail bound of accumulated cost until program termination.Our approach can handle both positive and negative costs.Moreover,our approach enables an automated template-based synthesis of supermartingales and leads to an efficient polynomial-time algorithm.To show the effectiveness of our approach,we present experimental results on various programs and make a comparison with state-of-the-art tools.展开更多
BACKGROUND Laparoscopic Heller myotomy(LHM)has been the traditional surgical treatment for achalasia.Recently,peroral endoscopic myotomy(POEM)has demonstrated similar clinical outcomes with shorter procedure times.Stu...BACKGROUND Laparoscopic Heller myotomy(LHM)has been the traditional surgical treatment for achalasia.Recently,peroral endoscopic myotomy(POEM)has demonstrated similar clinical outcomes with shorter procedure times.Studies comparing the direct cost-effectiveness of POEM vs LHM are limited.AIM To compare costs of POEM vs LHM.METHODS Haider SA et al.Comparing costs:POEM vs Heller myotomy WJGE https://www.wjgnet.com 594 October 16,2023 Volume 15 Issue 10 This retrospective chart review aimed to compare the outcomes and cost of clinical care between patients who underwent POEM and LHM procedures for achalasia.The study was conducted at a tertiary academic center from January 2019 to December 2020.Clinical outcomes,including post-operative Eckardt scores and adverse events,were assessed and compared between the two groups.Direct cost variance analysis was utilized to evaluate the cost of clinical care incurred by patients undergoing POEM in the year preceding the procedure,during the index admission,and one year post-procedure,in comparison to patients undergoing LHM.RESULTS Of 30 patients were included(15 POEM and 15 LHM)in the study.Patients in the POEM group had a mean Eckardt score of 0.5±0.5 post-procedure,which was no different from patients in the LHM group(0.7±0.6,P=0.17)indicating comparative efficacy.However,the total costs of the admission for the procedure in the LHM group were on average$1827 more expensive than in the POEM group(P<0.01).Total healthcare costs one year prior to index procedure were$7777 higher in the LHM group,but not statistically different(P=0.34).The patients in the LHM group one year after the index procedure had accrued$19730.24 larger total cost,although this was not statistically different from POEM group(P=0.68).CONCLUSION Despite similar clinical outcomes,the cost of the index procedure admission for POEM was significantly lower than for LHM.The difference was primarily related to shorter time increments utilized in the operating room during the index procedure,and shorter length of hospital stay following POEM.展开更多
Objective:Treatment options for metastatic castration resistant prostate cancer(mCRPC)have expanded rapidly in recent years.Given the significant economic burden,we sought perform a cost-effectiveness analysis(CEA)of ...Objective:Treatment options for metastatic castration resistant prostate cancer(mCRPC)have expanded rapidly in recent years.Given the significant economic burden,we sought perform a cost-effectiveness analysis(CEA)of the contemporary treatment paradigm for mCRPC.Methods:We devised a treatment protocol consisting of sipuleucel-T,enzalutamide,abiraterone,docetaxel,radium-223,and cabazitaxel.We estimated number and length of treatments for each therapy using dosing schedules or progression free survival data from published clinical trials.We estimated treatment cost using billing data and Medicare reimbursement values and performed a CEA.Our analysis assumed US$100,000 per life year saved(LYS)as the threshold societal willingness to pay.Results:Incremental cost-effectiveness ratios(ICER)for strategies incorporating sipuleucel-T that were not eliminated by extended dominance exceeded the societal threshold willingnessto-pay of US$100,000 per LYS,the lowest of which was sipuleucel-T+enzalutamide+abiraterone+docetaxel at US$207,714 per LYS.Enzalutamide+abiraterone+docetaxel exhibited the most favorable ICER among strategies without sipuleucel-T at US$165,460 per LYS.Conclusion:Based on the available survival data and current costs of treatment,all treatment strategies greatly exceed a commonly assumed societal willingness-to-pay threshold of US$100,000 per LYS.Improvements in this regard can only comewith a reduction in pricing,better tailoring of treatment or significant enhancements in survival with clinical use of treatment combinations or sequences.展开更多
Background: Cervical cancer shows a growing incidence and medical cost in recent years that has increased severe financial pressure on patients and medical insurance institutions. This study aimed to investigate the ...Background: Cervical cancer shows a growing incidence and medical cost in recent years that has increased severe financial pressure on patients and medical insurance institutions. This study aimed to investigate the medical economic characteristics of cervical cancer patients with different payment modes within a Grade A tertiary hospital to provide evidence and suggestions for inpatient cost control and to verily the application of Gamma model in medical cost analysis. Methods: The basic and cost information of cervical cancer cases within a Grade A tertiary hospital in the year 2011-2016 were collected. The Gamma model was adopted to analyze the differences in each cost item between medical insured patient and uninsured patients. Meanwhile, the marginal means of different cost items were calculated to estimate the influence of payment modes toward different medical cost items among cervical cancer patients in the study. Results: A total of 1321 inpatients with cervical cancer between the 2011 and 2016 were collected through the medical records system. Of the 1321 cases~ 65.9% accounted for medical insured patients and 34.1% were uninsured patients. The total inpatient medical expenditure of insured patients was RMB 29,509.1 Yuan and uninsured patients was RMB 22,114.3 Yuan, respectively. Payment modes, therapeutic options as well as the recurrence and metastasis of tumor toward the inpatient medical expenditures between the two groups were statistically significant. To the specifics, drug costs accounted for 37.7% and 33.8% of the total, surgery costs accounted for 21.5% and 25.5%, treatment costs accounted for 18.7% and 16.4%, whereas the costs of imaging and laboratory examinations accounted for 16.4% and 15.2% for the insured patient and uninsured patients, respectively. As the effects of covariates were controlled, the total hospitalization costs, drug costs, treatment costs as well as imaging and laboratory exainination costs showed statistical significance. The total hospitalization costs, drug costs, treatment costs as well as imaging and laboratory examination costs of insured patient were 1.33, 1.42, 1.52, and 1.44 times of uninsured patients. Conclusions: The analysis of different payment modes toward the medical economic characteristics based on Gamma model is basically rational. Medical payment modes are having certain influence toward the hospitalization expenses of cervical cancer patients in an extent, as drug costs, treatment costs, and examination costs appear to be the main causes.展开更多
Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of ...Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China.Methods:A number of study sites(eight counties in five provinces)were selected from the malaria endemic area in China,representing the different levels of malaria incidence,risk classification,economic development.A number of households with malaria cases(n=923)were surveyed during the May to December in 2012 to collect information on malaria economic burden.Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender,age group,occupation and malaria type.The malaria economic costs were evaluated by direct and indirect costs.Comparisons were carried out by using the chi-square test(or Z-test)and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients,hospitalized/out patients,and treatment hospitals.Results:The average cost of malaria per case was 1691.23 CNY(direct cost was 735.41 CNY and indirect cost was 955.82 CNY),which accounted for 11.1%of a household’s total income.The average costs per case for local and imported malaria were 1087.58 CNY and 4271.93 CNY,respectively.The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above(3975.43 CNY)was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital(938.80 CNY).Conclusion:This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs.There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria,especially of imported infections,in order to eliminate the disease in China.展开更多
Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analy...Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analysis (LCCA) model to quantify the impact of pavement preservation on agency cost and vehicle operation cost (VOC) and analyzed the optimal timing of preservation treatments. The international roughness index (IRI) data were extracted from the long-term pavement performance (LTPP) program specific pavement studies 3 (SPS-3) to determine the long-term effectiveness of preservation treatments on IRI deterioration. The traffic loading and the initial IRI value significantly affects life extension and the benefit of agency cost caused by pavement preservation. The benefit in VOC is one to two orders greater in magnitude as compared to the benefit in agency cost. The optimal timing calculated based on VOC is always earlier than the optimal timing calculated based on agency cost. There are considerable differences among the optimal timing of three preservation treatments.展开更多
A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas r...A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.展开更多
Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.The economic feasibility becomes one of the greatest issues when we apply this new technology.Evaluation of economic fea...Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.The economic feasibility becomes one of the greatest issues when we apply this new technology.Evaluation of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift modes.The objective of this study was to evaluate the unit cost of biofuel products(Liquid HCs,Light HCs and Oxygenates CxHyOz)under different capacities using a modeling method.The cost analysis model was developed using Visual Basic Microsoft 2008,computer programming language and mathematical equations.The modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of facilities.As the facility capacity increased from 65 to 10,000 N m^3 h^-1,the biofuel production unit cost of gas(Light HCs),oil(Liquid HCs),and aqueous(Oxygenates CxHyOz)decreased from$38.92 per MMBTU,$30.89 per gallon and$25.74 per gallon to$2.01 per MMBTU,$1.59 per gallon,and$1.33 per gallon,respectively.The results of the sensitivity analysis showed that feedstock cost was the most sensitive cost factor on unit costs for all biofuel products at high capacity.The cost analysis model developed in this study could be used to optimize production unit costs of bio-fuel products from bio-gasification facility.展开更多
Formwork is the temporary moulds in the construction which is fabricated based on the drawing and design of the structure and into which the concrete is poured to form the required structure.Formwork is an essential p...Formwork is the temporary moulds in the construction which is fabricated based on the drawing and design of the structure and into which the concrete is poured to form the required structure.Formwork is an essential part of the construction as it has been used by the Romans.The formworks must be strong enough to withstand all types of loads.The joint must be in proper condition to avoid any kind of leakages.The materials used for the formworks should be economical,easily available and durable.The formworks can be made up of different materials such as plywood,steel,aluminum,composite material,etc.In steel formwork the plates used for the slab support are made up of galvanized steel and these are fabricated as per the requirements.Aluminum plates are used in the aluminum framework along with the other components made up of aluminum.The selection of a suitable framework is important in any project because it bears about 25%to 30%cost of the total cost of construction.In the present study,different types of formworks such as steel,plywood and aluminum were studied in a project and a comparison was made on the reusability and easiness in handling and maintenance.Also,a comparison of the formwork used in the construction of the 5th and 11th-floor tower based on the specific plan and drawing was done.The results showed that the aluminum formwork was found to be efficient and suitable among all formworks,although the cost was higher compared to other formwork materials.展开更多
Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span...Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs.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
The shortage of natural aggregates is becoming a severe problem in the pavement industry globally.To address this issue,in this study,an effort was made to use reclaimed asphalt pavement(RAP)and coal gangue(CG)as coar...The shortage of natural aggregates is becoming a severe problem in the pavement industry globally.To address this issue,in this study,an effort was made to use reclaimed asphalt pavement(RAP)and coal gangue(CG)as coarse and fine aggregate,respectively for producing the hot mix asphalt(HMA).As the replacement of natural aggregate,there were seven types of HMA containing 20%and 40%RAP coarse aggregate content,and 10%and 25%CG fine aggregate content were designed and prepared.In addition,Marshall Stability test,rutting resistance test,immersion Marshall test,freezing-thaw splitting test,moisture-induced sensitivity test,and low-temperature semicircle bending test were conducted.The results show that the properties of the asphalt mixture containing both RAP and CG meet the Chinese specification through it is slightly lower than the virgin asphalt mixture.Furthermore,the addition of 40%RAP coarse aggregate and 25%CG fine aggregate to asphalt mixes can significantly reduce manufacturing costs,energy consumption,and CO_(2)emissions by 29.4%,19.8%,and 21.9%,respectively,compared to the virgin asphalt mixture.The finding of this study contributes to current knowledge by investigating the feasibility of jointly using the RAP and CG in asphalt mixture,which could be interested by both industry and academic society.展开更多
The environmental and energy problems that have arisen in Turkey because of the dramatically increase in energy consumption require the implementation of energy efficiency and microgeneration measures in the building ...The environmental and energy problems that have arisen in Turkey because of the dramatically increase in energy consumption require the implementation of energy efficiency and microgeneration measures in the building sector which is the main sector of primary energy consumption. Since Turkey is highly dependent on exported energy resources, the basic energy policy approach is based on providing the supply security. In this regard, supporting for in situ energy production, encouraging the use of renewable energy sources and the systems such as microgeneration systems in order to meet the energy requirements of buildings would be considered as a key measure for resolving the energy related challenges of Turkey and dealing with the sustainability issues. Turkey’s geographical location has several advantages for extensive use of most of the renewable energy sources such as especially solar energy. However, this huge solar energy potential is not being used sufficiently in residential building sector which is responsible for the great energy consumption of Turkey. Therefore, this paper aims to introduce a study which investigates, on a life cycle basis, the environmental and the economic sustainability of solar Photovoltaic (PV) microgenerators to promote the implementation of this system as an option for the renovation of existing residential buildings in Turkey. In this study, main parameters which were related to the distribution of modules to be installed in flat roofs and facades and the evaluation of the PV systems were taken into account. The effect of these parameters on energy generation of PV systems was analyzed in a case study considering different climate zones of Turkey;and the decrease in the existing energy consumption of the reference building was calculated.展开更多
Purpose: To compare the strategy for mild stimulation IVF versus conventional stimulation IVF. Methods: A decision tree analytic model was created to compare IVF with mild stimulation versus convention stimulation in ...Purpose: To compare the strategy for mild stimulation IVF versus conventional stimulation IVF. Methods: A decision tree analytic model was created to compare IVF with mild stimulation versus convention stimulation in infertile women <38 years of age to evaluate which strategy is the least costly per live birth. Results: Using base-case estimates of costs and probabilities in women <38 years old with unexplained infertility, the cumulative live birth rate in the mild versus conventional stimulation group was 15.8% versus 28.6%, respectively. The average cost for mild and convention IVF was $8789 and $14,364 per arm, respectively. In base case analysis, the ICER was $43,516 representing the additional cost per live birth with conventional IVF. One-way sensitivity analysis evaluated the robustness of the data and revealed a tradeoff in which mild IVF stimulation had lower total costs and also lower live births versus conventional stimulation. Conclusions: Mild stimulation IVF has a lower cost per cycle but is also associated with lower live birth rates. Patient care decisions should be individualized irrespective of cost.展开更多
In this technical and educational research endeavor, a diverse group of civil engineering students took on the role of creating the means and methods of producing a successful building design. Architectural, structura...In this technical and educational research endeavor, a diverse group of civil engineering students took on the role of creating the means and methods of producing a successful building design. Architectural, structural, and environmental designs were primarily performed. This was followed by detailed cost analysis with the intent of providing a realistic cost comparison by pricing the intended building, using traditional material and typical building methods, versus pricing the building using recycled material and new present-day technology. Some green features needed to achieve a LEED (Leadership in Energy and Environmental Design) gold certification were considered and applied. It is shown that producing a green building is more costly in present circumstances;however, the additional cost due to greenification pays itself off throughout the years giving in return saving features. Even though the design of a green building comes with detailed planning and costly material, it does generate benefits for the building owner, the society, and most importantly the environment.展开更多
Background: Various psychotherapies are used extensively in treating different mental disorders, but still relatively little is known about the long-term health and cost effects of different therapies. The aim of this...Background: Various psychotherapies are used extensively in treating different mental disorders, but still relatively little is known about the long-term health and cost effects of different therapies. The aim of this study is to compare the cost-effectiveness of short-term psychodynamic psychotherapy (SPP) and solution-focused therapy (SFT) in the treatment of depressive and anxiety disorders during a three-year follow-up. Methods: A total of 198 outpatients suffering from mood or anxiety disorder were randomized to SPP or SFT. Symptoms were assessed using the Beck Depression Inventory, the Hamilton Depression Rating Scale, the Symptom Check List Anxiety Scale, the Hamilton Anxiety Rating Scale, and the Symptom Check List Global Severity Index. Both direct and indirect costs due to mental health problems were measured. Results: The symptoms of depression and anxiety were reduced statistically significantly according to all 5 psychiatric outcome measures during the first 7 months, after which only minor changes were observed. The differences between the two groups were small and not statistically significant. The direct costs were about equal in both groups but the indirect costs were somewhat higher in the SPP group, although not statistically significantly. The costs of auxiliary treatments were much higher than the cost of SPP or SFT. Conclusions: With regard to cost-effectiveness, there is little difference between SPP and SFT.展开更多
Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and proper...Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and property value. Additional benefits may result from the potential recovery of valuable resources from wastewater and solid waste, such as compost, energy, phosphorus, plastics and paper. Improving water quality through implementation of wastewater and solid waste interventions requires, among others, an analysis of i) sources of pollution, ii) mitigating measures and resource recovery potentials and their effect on water quality and health, and iii) benefits and costs of interventions. We present an integrated approach to evaluate costs and benefits of domestic and industrial wastewater and solid waste interventions. To support a policy maker in formulating a cost and environmentally effective approach, we quantified the impact of these interventions on 1) water quality improvement, 2) resource recovery potential, and 3) monetized benefits versus costs. The integration of technical, hydrological, agronomical and socio-economic elements to derive these three tangible outputs in a joint approach is a novelty. The approach is demonstrated using the heavily polluted Indonesian Upper Citarum River in the Bandung region. Domestic interventions, applying simple (anaerobic filter) technologies, were economically most attractive with a benefit cost ratio (BCR) of 3.2, but could not reach target water quality standards. To approach the target water quality, both advanced domestic (nutrient removal systems) and industrial wastewater treatment interventions were required, leading to a BCR of 2. We showed that benefits from selling recovered resources represent here an additional driver for improving water quality and outweigh the additional costs for resource recovery facilities. While included benefits captured some of the major items, these may have been undervalued. Based on these findings, water quality interventions justify their costs and are socially and economically beneficial.展开更多
In 2012, genetically engineered (GE) crops were grown by 17.3 million farmers on over 170 million hectares. Over 70% of harvested GE biomass is fed to food producing animals, making them the major consumers of GE cr...In 2012, genetically engineered (GE) crops were grown by 17.3 million farmers on over 170 million hectares. Over 70% of harvested GE biomass is fed to food producing animals, making them the major consumers of GE crops for the past 15 plus years. Prior to commercialization, GE crops go through an extensive regulatory evaluation. Over one hundred regulatory submissions have shown compositional equivalence, and comparable levels of safety, between GE crops and their conventional counterparts. One component of regulatory compliance is whole GE food/feed animal feeding studies. Both regulatory studies and independent peer-reviewed studies have shown that GE crops can be safely used in animal feed, and rDNA fragments have never been detected in products (e.g. milk, meat, eggs) derived from animals that consumed GE feed. Despite the fact that the scientific weight of evidence from these hundreds of studies have not revealed unique risks associated with GE feed, some groups are calling for more animal feeding studies, including long-term rodent studies and studies in target livestock species for the approval of GE crops. It is an opportune time to review the results of such studies as have been done to date to evaluate the value of the additional information obtained. Requiring long-term and target animal feeding studies would sharply increase regulatory compliance costs and prolong the regulatory process associated with the commercialization of GE crops. Such costs may impede the development of feed crops with enhanced nutritional characteristics and durability, particularly in the local varieties in small and poor developing countries. More generally it is time for regulatory evaluations to more explicitly consider both the reasonable and unique risks and benefits associated with the use of both GE plants and animals in agricultural systems, and weigh them against those associated with existing systems, and those of regulatory inaction. This would represent a shift away from a GE evaluation process that currently focuses only on risk assessment and identifying ever diminishing marginal hazards, to a regulatory approach that more objectively evaluates and communicates the likely impact of approving a new GE plant or animal on agricultural production systems.展开更多
Protecting groundwater from lead contamination is an important public-health concern and a major national environmental issue worldwide. This article addresses myGeoffice Web Internet service for geographers, in gener...Protecting groundwater from lead contamination is an important public-health concern and a major national environmental issue worldwide. This article addresses myGeoffice Web Internet service for geographers, in general, and geo-statistics researchers, in particular, with the famous water contamination case at Jura lake, Switzerland (a typical rural-urban region). Based on 189 samples of lead (Pb), five key investigation steps for a scientific perspective of any pollution incident are presented: Descriptive analysis (including nearest neighborhood, G(h) and Kernel techniques), spatial autocorrelation (Moran location scatterplot and Moran I) and Ordinary Kriging (OK) interpolation. The uncertainty and cost assessments issues are exceptionally tackled with Indicator Kriging (including the conditional cumulative distribution function, Shannon local entropy, probabilistic intervals and E-type estimation) and Gaussian geo-simulation. The total lead pollution exhibited patterns of high and low levels of concentrations along the all lake, leading to the conclusion that water is unsuitable for human consumption, in general, and unsuitable for any living organism, in particular sub-areas. It is also hoped that future GIS readers will follow this approach for their spatial cases with myGeoffice.展开更多
文摘AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quantitate the reduction of mean IOP and glaucoma medications for each surgical intervention in childhood glaucoma. A US perspective was adopted, using Medicare allowable costs to calculate cost/mm Hg IOP reduction($/mm Hg) at 1y postoperatively.RESULTS: At 1y postoperatively, the cost/mm Hg IOP reduction was $226/mm Hg for microcatheter-assisted circumferential trabeculotomy, $284/mm Hg for cyclophotocoagulation, $288/mm Hg for conventional ab-externo trabeculotomy, $338/mm Hg for Ahmed glaucoma valve, $350/mm Hg for Baerveldt glaucoma implant, $351/mm Hg for goniotomy, and $400/mm Hg for trabeculectomy.CONCLUSION: Microcatheter-assisted circumferential trabeculotomy is the most cost-efficient surgical method to lower IOP in childhood glaucoma, while trabeculectomy is the least cost-efficient surgical method.
基金the National Natural Science Foundation of China(Nos.61802254,62072299,and 61772336)。
文摘For probabilistic programs,there is some work for qualitative and quantitative analysis about expec-tation or mean,such as expected termination time,and expected cost analysis.However,another non-trivial issue is about tail bounds(i.e.,upper bounds of tail probabilities),which can provide high-probability guarantees to extreme events.In this work,we focus on the problem of tail-bound cost analysis over nondeterministic proba-bilistic programs,which aims to automatically obtain the tail bound of resource usages over such programs.To achieve this goal,we present a novel approach,combined with a suitable concentration inequality,to derive the tail bound of accumulated cost until program termination.Our approach can handle both positive and negative costs.Moreover,our approach enables an automated template-based synthesis of supermartingales and leads to an efficient polynomial-time algorithm.To show the effectiveness of our approach,we present experimental results on various programs and make a comparison with state-of-the-art tools.
文摘BACKGROUND Laparoscopic Heller myotomy(LHM)has been the traditional surgical treatment for achalasia.Recently,peroral endoscopic myotomy(POEM)has demonstrated similar clinical outcomes with shorter procedure times.Studies comparing the direct cost-effectiveness of POEM vs LHM are limited.AIM To compare costs of POEM vs LHM.METHODS Haider SA et al.Comparing costs:POEM vs Heller myotomy WJGE https://www.wjgnet.com 594 October 16,2023 Volume 15 Issue 10 This retrospective chart review aimed to compare the outcomes and cost of clinical care between patients who underwent POEM and LHM procedures for achalasia.The study was conducted at a tertiary academic center from January 2019 to December 2020.Clinical outcomes,including post-operative Eckardt scores and adverse events,were assessed and compared between the two groups.Direct cost variance analysis was utilized to evaluate the cost of clinical care incurred by patients undergoing POEM in the year preceding the procedure,during the index admission,and one year post-procedure,in comparison to patients undergoing LHM.RESULTS Of 30 patients were included(15 POEM and 15 LHM)in the study.Patients in the POEM group had a mean Eckardt score of 0.5±0.5 post-procedure,which was no different from patients in the LHM group(0.7±0.6,P=0.17)indicating comparative efficacy.However,the total costs of the admission for the procedure in the LHM group were on average$1827 more expensive than in the POEM group(P<0.01).Total healthcare costs one year prior to index procedure were$7777 higher in the LHM group,but not statistically different(P=0.34).The patients in the LHM group one year after the index procedure had accrued$19730.24 larger total cost,although this was not statistically different from POEM group(P=0.68).CONCLUSION Despite similar clinical outcomes,the cost of the index procedure admission for POEM was significantly lower than for LHM.The difference was primarily related to shorter time increments utilized in the operating room during the index procedure,and shorter length of hospital stay following POEM.
文摘Objective:Treatment options for metastatic castration resistant prostate cancer(mCRPC)have expanded rapidly in recent years.Given the significant economic burden,we sought perform a cost-effectiveness analysis(CEA)of the contemporary treatment paradigm for mCRPC.Methods:We devised a treatment protocol consisting of sipuleucel-T,enzalutamide,abiraterone,docetaxel,radium-223,and cabazitaxel.We estimated number and length of treatments for each therapy using dosing schedules or progression free survival data from published clinical trials.We estimated treatment cost using billing data and Medicare reimbursement values and performed a CEA.Our analysis assumed US$100,000 per life year saved(LYS)as the threshold societal willingness to pay.Results:Incremental cost-effectiveness ratios(ICER)for strategies incorporating sipuleucel-T that were not eliminated by extended dominance exceeded the societal threshold willingnessto-pay of US$100,000 per LYS,the lowest of which was sipuleucel-T+enzalutamide+abiraterone+docetaxel at US$207,714 per LYS.Enzalutamide+abiraterone+docetaxel exhibited the most favorable ICER among strategies without sipuleucel-T at US$165,460 per LYS.Conclusion:Based on the available survival data and current costs of treatment,all treatment strategies greatly exceed a commonly assumed societal willingness-to-pay threshold of US$100,000 per LYS.Improvements in this regard can only comewith a reduction in pricing,better tailoring of treatment or significant enhancements in survival with clinical use of treatment combinations or sequences.
文摘Background: Cervical cancer shows a growing incidence and medical cost in recent years that has increased severe financial pressure on patients and medical insurance institutions. This study aimed to investigate the medical economic characteristics of cervical cancer patients with different payment modes within a Grade A tertiary hospital to provide evidence and suggestions for inpatient cost control and to verily the application of Gamma model in medical cost analysis. Methods: The basic and cost information of cervical cancer cases within a Grade A tertiary hospital in the year 2011-2016 were collected. The Gamma model was adopted to analyze the differences in each cost item between medical insured patient and uninsured patients. Meanwhile, the marginal means of different cost items were calculated to estimate the influence of payment modes toward different medical cost items among cervical cancer patients in the study. Results: A total of 1321 inpatients with cervical cancer between the 2011 and 2016 were collected through the medical records system. Of the 1321 cases~ 65.9% accounted for medical insured patients and 34.1% were uninsured patients. The total inpatient medical expenditure of insured patients was RMB 29,509.1 Yuan and uninsured patients was RMB 22,114.3 Yuan, respectively. Payment modes, therapeutic options as well as the recurrence and metastasis of tumor toward the inpatient medical expenditures between the two groups were statistically significant. To the specifics, drug costs accounted for 37.7% and 33.8% of the total, surgery costs accounted for 21.5% and 25.5%, treatment costs accounted for 18.7% and 16.4%, whereas the costs of imaging and laboratory examinations accounted for 16.4% and 15.2% for the insured patient and uninsured patients, respectively. As the effects of covariates were controlled, the total hospitalization costs, drug costs, treatment costs as well as imaging and laboratory exainination costs showed statistical significance. The total hospitalization costs, drug costs, treatment costs as well as imaging and laboratory examination costs of insured patient were 1.33, 1.42, 1.52, and 1.44 times of uninsured patients. Conclusions: The analysis of different payment modes toward the medical economic characteristics based on Gamma model is basically rational. Medical payment modes are having certain influence toward the hospitalization expenses of cervical cancer patients in an extent, as drug costs, treatment costs, and examination costs appear to be the main causes.
基金supported by the National Natural Science Foundation of China(No.81101280)the National Special Science and Technology Project for Major Infectious Diseases of China(Grant Nos.2012ZX10004-220,2008ZX10004-011,and 2012ZX10004-201)+1 种基金the China UK Global Health Support Programme(GHSP-CS-OP101)-China’s Experiences in Control of Malaria and Schistosomiasis:Relevant to LMICs through Distillation,Synthesis and Dissemination Approaches,the Public Health Overseas Fund,the Bureau of Health,Shanghai(Grant No.GWHW201216)the Shanghai Public Health Improvement Action Plan 2015–2017,and the Global Fund Project in China.The funders had no role in the study design,data collection and analysis,decision to publish,or preparation of the paper.
文摘Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China.Methods:A number of study sites(eight counties in five provinces)were selected from the malaria endemic area in China,representing the different levels of malaria incidence,risk classification,economic development.A number of households with malaria cases(n=923)were surveyed during the May to December in 2012 to collect information on malaria economic burden.Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender,age group,occupation and malaria type.The malaria economic costs were evaluated by direct and indirect costs.Comparisons were carried out by using the chi-square test(or Z-test)and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients,hospitalized/out patients,and treatment hospitals.Results:The average cost of malaria per case was 1691.23 CNY(direct cost was 735.41 CNY and indirect cost was 955.82 CNY),which accounted for 11.1%of a household’s total income.The average costs per case for local and imported malaria were 1087.58 CNY and 4271.93 CNY,respectively.The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above(3975.43 CNY)was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital(938.80 CNY).Conclusion:This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs.There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria,especially of imported infections,in order to eliminate the disease in China.
文摘Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analysis (LCCA) model to quantify the impact of pavement preservation on agency cost and vehicle operation cost (VOC) and analyzed the optimal timing of preservation treatments. The international roughness index (IRI) data were extracted from the long-term pavement performance (LTPP) program specific pavement studies 3 (SPS-3) to determine the long-term effectiveness of preservation treatments on IRI deterioration. The traffic loading and the initial IRI value significantly affects life extension and the benefit of agency cost caused by pavement preservation. The benefit in VOC is one to two orders greater in magnitude as compared to the benefit in agency cost. The optimal timing calculated based on VOC is always earlier than the optimal timing calculated based on agency cost. There are considerable differences among the optimal timing of three preservation treatments.
文摘A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.
基金This material is based upon work performed through the Sustainable Energy Research Center at Mississippi State University,and is supported by the Department of Energy under Award Number DE-FG3606GO86025Micro CHP and Biofuel Center.
文摘Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.The economic feasibility becomes one of the greatest issues when we apply this new technology.Evaluation of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift modes.The objective of this study was to evaluate the unit cost of biofuel products(Liquid HCs,Light HCs and Oxygenates CxHyOz)under different capacities using a modeling method.The cost analysis model was developed using Visual Basic Microsoft 2008,computer programming language and mathematical equations.The modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of facilities.As the facility capacity increased from 65 to 10,000 N m^3 h^-1,the biofuel production unit cost of gas(Light HCs),oil(Liquid HCs),and aqueous(Oxygenates CxHyOz)decreased from$38.92 per MMBTU,$30.89 per gallon and$25.74 per gallon to$2.01 per MMBTU,$1.59 per gallon,and$1.33 per gallon,respectively.The results of the sensitivity analysis showed that feedstock cost was the most sensitive cost factor on unit costs for all biofuel products at high capacity.The cost analysis model developed in this study could be used to optimize production unit costs of bio-fuel products from bio-gasification facility.
文摘Formwork is the temporary moulds in the construction which is fabricated based on the drawing and design of the structure and into which the concrete is poured to form the required structure.Formwork is an essential part of the construction as it has been used by the Romans.The formworks must be strong enough to withstand all types of loads.The joint must be in proper condition to avoid any kind of leakages.The materials used for the formworks should be economical,easily available and durable.The formworks can be made up of different materials such as plywood,steel,aluminum,composite material,etc.In steel formwork the plates used for the slab support are made up of galvanized steel and these are fabricated as per the requirements.Aluminum plates are used in the aluminum framework along with the other components made up of aluminum.The selection of a suitable framework is important in any project because it bears about 25%to 30%cost of the total cost of construction.In the present study,different types of formworks such as steel,plywood and aluminum were studied in a project and a comparison was made on the reusability and easiness in handling and maintenance.Also,a comparison of the formwork used in the construction of the 5th and 11th-floor tower based on the specific plan and drawing was done.The results showed that the aluminum formwork was found to be efficient and suitable among all formworks,although the cost was higher compared to other formwork materials.
文摘Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs.
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the Natural Science Foundation of Jiangxi Province of China(Grant No.20202BABL214046)lthe Natural Science Foundation of Uygur Autonomous Region of China(Grant No.2020D01A92)l the China Postdoctoral Science Foundation(2020M683709XB).
文摘The shortage of natural aggregates is becoming a severe problem in the pavement industry globally.To address this issue,in this study,an effort was made to use reclaimed asphalt pavement(RAP)and coal gangue(CG)as coarse and fine aggregate,respectively for producing the hot mix asphalt(HMA).As the replacement of natural aggregate,there were seven types of HMA containing 20%and 40%RAP coarse aggregate content,and 10%and 25%CG fine aggregate content were designed and prepared.In addition,Marshall Stability test,rutting resistance test,immersion Marshall test,freezing-thaw splitting test,moisture-induced sensitivity test,and low-temperature semicircle bending test were conducted.The results show that the properties of the asphalt mixture containing both RAP and CG meet the Chinese specification through it is slightly lower than the virgin asphalt mixture.Furthermore,the addition of 40%RAP coarse aggregate and 25%CG fine aggregate to asphalt mixes can significantly reduce manufacturing costs,energy consumption,and CO_(2)emissions by 29.4%,19.8%,and 21.9%,respectively,compared to the virgin asphalt mixture.The finding of this study contributes to current knowledge by investigating the feasibility of jointly using the RAP and CG in asphalt mixture,which could be interested by both industry and academic society.
文摘The environmental and energy problems that have arisen in Turkey because of the dramatically increase in energy consumption require the implementation of energy efficiency and microgeneration measures in the building sector which is the main sector of primary energy consumption. Since Turkey is highly dependent on exported energy resources, the basic energy policy approach is based on providing the supply security. In this regard, supporting for in situ energy production, encouraging the use of renewable energy sources and the systems such as microgeneration systems in order to meet the energy requirements of buildings would be considered as a key measure for resolving the energy related challenges of Turkey and dealing with the sustainability issues. Turkey’s geographical location has several advantages for extensive use of most of the renewable energy sources such as especially solar energy. However, this huge solar energy potential is not being used sufficiently in residential building sector which is responsible for the great energy consumption of Turkey. Therefore, this paper aims to introduce a study which investigates, on a life cycle basis, the environmental and the economic sustainability of solar Photovoltaic (PV) microgenerators to promote the implementation of this system as an option for the renovation of existing residential buildings in Turkey. In this study, main parameters which were related to the distribution of modules to be installed in flat roofs and facades and the evaluation of the PV systems were taken into account. The effect of these parameters on energy generation of PV systems was analyzed in a case study considering different climate zones of Turkey;and the decrease in the existing energy consumption of the reference building was calculated.
文摘Purpose: To compare the strategy for mild stimulation IVF versus conventional stimulation IVF. Methods: A decision tree analytic model was created to compare IVF with mild stimulation versus convention stimulation in infertile women <38 years of age to evaluate which strategy is the least costly per live birth. Results: Using base-case estimates of costs and probabilities in women <38 years old with unexplained infertility, the cumulative live birth rate in the mild versus conventional stimulation group was 15.8% versus 28.6%, respectively. The average cost for mild and convention IVF was $8789 and $14,364 per arm, respectively. In base case analysis, the ICER was $43,516 representing the additional cost per live birth with conventional IVF. One-way sensitivity analysis evaluated the robustness of the data and revealed a tradeoff in which mild IVF stimulation had lower total costs and also lower live births versus conventional stimulation. Conclusions: Mild stimulation IVF has a lower cost per cycle but is also associated with lower live birth rates. Patient care decisions should be individualized irrespective of cost.
文摘In this technical and educational research endeavor, a diverse group of civil engineering students took on the role of creating the means and methods of producing a successful building design. Architectural, structural, and environmental designs were primarily performed. This was followed by detailed cost analysis with the intent of providing a realistic cost comparison by pricing the intended building, using traditional material and typical building methods, versus pricing the building using recycled material and new present-day technology. Some green features needed to achieve a LEED (Leadership in Energy and Environmental Design) gold certification were considered and applied. It is shown that producing a green building is more costly in present circumstances;however, the additional cost due to greenification pays itself off throughout the years giving in return saving features. Even though the design of a green building comes with detailed planning and costly material, it does generate benefits for the building owner, the society, and most importantly the environment.
基金The Academy of Finland (Grant No. 138876) the Social Insurance Institution of Finland
文摘Background: Various psychotherapies are used extensively in treating different mental disorders, but still relatively little is known about the long-term health and cost effects of different therapies. The aim of this study is to compare the cost-effectiveness of short-term psychodynamic psychotherapy (SPP) and solution-focused therapy (SFT) in the treatment of depressive and anxiety disorders during a three-year follow-up. Methods: A total of 198 outpatients suffering from mood or anxiety disorder were randomized to SPP or SFT. Symptoms were assessed using the Beck Depression Inventory, the Hamilton Depression Rating Scale, the Symptom Check List Anxiety Scale, the Hamilton Anxiety Rating Scale, and the Symptom Check List Global Severity Index. Both direct and indirect costs due to mental health problems were measured. Results: The symptoms of depression and anxiety were reduced statistically significantly according to all 5 psychiatric outcome measures during the first 7 months, after which only minor changes were observed. The differences between the two groups were small and not statistically significant. The direct costs were about equal in both groups but the indirect costs were somewhat higher in the SPP group, although not statistically significantly. The costs of auxiliary treatments were much higher than the cost of SPP or SFT. Conclusions: With regard to cost-effectiveness, there is little difference between SPP and SFT.
文摘Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and property value. Additional benefits may result from the potential recovery of valuable resources from wastewater and solid waste, such as compost, energy, phosphorus, plastics and paper. Improving water quality through implementation of wastewater and solid waste interventions requires, among others, an analysis of i) sources of pollution, ii) mitigating measures and resource recovery potentials and their effect on water quality and health, and iii) benefits and costs of interventions. We present an integrated approach to evaluate costs and benefits of domestic and industrial wastewater and solid waste interventions. To support a policy maker in formulating a cost and environmentally effective approach, we quantified the impact of these interventions on 1) water quality improvement, 2) resource recovery potential, and 3) monetized benefits versus costs. The integration of technical, hydrological, agronomical and socio-economic elements to derive these three tangible outputs in a joint approach is a novelty. The approach is demonstrated using the heavily polluted Indonesian Upper Citarum River in the Bandung region. Domestic interventions, applying simple (anaerobic filter) technologies, were economically most attractive with a benefit cost ratio (BCR) of 3.2, but could not reach target water quality standards. To approach the target water quality, both advanced domestic (nutrient removal systems) and industrial wastewater treatment interventions were required, leading to a BCR of 2. We showed that benefits from selling recovered resources represent here an additional driver for improving water quality and outweigh the additional costs for resource recovery facilities. While included benefits captured some of the major items, these may have been undervalued. Based on these findings, water quality interventions justify their costs and are socially and economically beneficial.
基金support from National Research Initiative Competitive Grant no.2009-55205-05057Agriculture and Food Research Initiative Competitive Grant no.2011-68004-30367 and 2013-68004-20364 from the USDA National Institute of Food and Agriculturesupported by funds from the W.K.Kellogg endowment to the UC Davis Department of Animal Science
文摘In 2012, genetically engineered (GE) crops were grown by 17.3 million farmers on over 170 million hectares. Over 70% of harvested GE biomass is fed to food producing animals, making them the major consumers of GE crops for the past 15 plus years. Prior to commercialization, GE crops go through an extensive regulatory evaluation. Over one hundred regulatory submissions have shown compositional equivalence, and comparable levels of safety, between GE crops and their conventional counterparts. One component of regulatory compliance is whole GE food/feed animal feeding studies. Both regulatory studies and independent peer-reviewed studies have shown that GE crops can be safely used in animal feed, and rDNA fragments have never been detected in products (e.g. milk, meat, eggs) derived from animals that consumed GE feed. Despite the fact that the scientific weight of evidence from these hundreds of studies have not revealed unique risks associated with GE feed, some groups are calling for more animal feeding studies, including long-term rodent studies and studies in target livestock species for the approval of GE crops. It is an opportune time to review the results of such studies as have been done to date to evaluate the value of the additional information obtained. Requiring long-term and target animal feeding studies would sharply increase regulatory compliance costs and prolong the regulatory process associated with the commercialization of GE crops. Such costs may impede the development of feed crops with enhanced nutritional characteristics and durability, particularly in the local varieties in small and poor developing countries. More generally it is time for regulatory evaluations to more explicitly consider both the reasonable and unique risks and benefits associated with the use of both GE plants and animals in agricultural systems, and weigh them against those associated with existing systems, and those of regulatory inaction. This would represent a shift away from a GE evaluation process that currently focuses only on risk assessment and identifying ever diminishing marginal hazards, to a regulatory approach that more objectively evaluates and communicates the likely impact of approving a new GE plant or animal on agricultural production systems.
文摘Protecting groundwater from lead contamination is an important public-health concern and a major national environmental issue worldwide. This article addresses myGeoffice Web Internet service for geographers, in general, and geo-statistics researchers, in particular, with the famous water contamination case at Jura lake, Switzerland (a typical rural-urban region). Based on 189 samples of lead (Pb), five key investigation steps for a scientific perspective of any pollution incident are presented: Descriptive analysis (including nearest neighborhood, G(h) and Kernel techniques), spatial autocorrelation (Moran location scatterplot and Moran I) and Ordinary Kriging (OK) interpolation. The uncertainty and cost assessments issues are exceptionally tackled with Indicator Kriging (including the conditional cumulative distribution function, Shannon local entropy, probabilistic intervals and E-type estimation) and Gaussian geo-simulation. The total lead pollution exhibited patterns of high and low levels of concentrations along the all lake, leading to the conclusion that water is unsuitable for human consumption, in general, and unsuitable for any living organism, in particular sub-areas. It is also hoped that future GIS readers will follow this approach for their spatial cases with myGeoffice.