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1.
Heliyon ; 10(5): e26754, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434305

RESUMO

Purpose: This study identified critical constraints in technology adoption for Direct Seeded Rice (DSR) compared with puddled transplanted rice (PTR) practices. We present the impact of DSR technology adoption on paddy yield, income generation, and cost incurred on various farm operations. Furthermore, the study investigates whether a dry DSR practice provides more economic and production benefits than a wet DSR. Methodology: We used a multi-stage sampling (from state to district-to-village-to-farmers) and conducted a face-to-face questionnaire survey to collect primary farm-level data. We collected 669 farm and household-level data and analyzed the impact of DSR and dry DSR adoption over PTR and wet DSR, respectively. Initially, the study employed probit regression analysis to identify the DSR adoption determinants. Subsequently, using the Propensity Score Matching approach, the study measures the impact of DSR adoption over PTR in terms of yield, income, and cost management. Finally, using the PSM approach, the study estimated the impact of dry DSR adoption over wet DSR. Findings: Probit estimates suggest that variables like education, membership in farmers' organizations, farm experience, institutional credit, crop insurance, off-farm income, and smartphone and television ownership positively regulate DSR adoption. The impact assessment analysis reveals that the adoption of DSR over PTR results in marginal yield improvement. However, the cost of irrigation, land preparation, and fertilization is significantly lower in DSR, resulting in an additional income of ₹5192/acre for DSR adopters. Moreover, a comparative analysis between dry DSR and wet DSR indicates that farmers can achieve ₹2467/acre by adopting dry DSR. Practical implications: Our research findings designate the necessity for implementing policies and strategies to promote the adoption of DSR among non-adopters. Besides economic benefits, adopting the DSR method can yield environmental benefits, improve soil health, mitigate soil erosion, and decrease water use.

2.
Bioresour Technol ; 399: 130641, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552861

RESUMO

This study presents a cost-effective strategy for producing organic acids from glucose and xylose using the acid-tolerant yeast, Issatchenkia orientalis. I. orientalis was engineered to produce lactic acid from xylose, and the resulting strain, SD108XL, successfully converted sorghum hydrolysates into lactic acid. In order to enable low-pH fermentation, a self-buffering strategy, where the lactic acid generated by the SD108XL strain during fermentation served as a buffer, was developed. As a result, the SD108 strain produced 67 g/L of lactic acid from 73 g/L of glucose and 40 g/L of xylose, simulating a sugar composition of sorghum biomass hydrolysates. Moreover, techno-economic analysis underscored the efficiency of the self-buffering strategy in streamlining the downstream process, thereby reducing production costs. These results demonstrate the potential of I. orientalis as a platform strain for the cost-effective production of organic acids from cellulosic hydrolysates.


Assuntos
Ácido Láctico , Pichia , Xilose , Glucose , Análise Custo-Benefício , Fermentação , Saccharomyces cerevisiae
3.
Environ Sci Pollut Res Int ; 31(15): 22319-22338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38430439

RESUMO

Advanced oxidation processes (AOPs) are wastewater treatment technologies that stand out for their ability to degrade Contaminants of Emerging Concern (CECs). The literature has extensively investigated these removal processes for different aqueous matrices. Once technically mature, some of these systems have become accredited to be applied on a large scale, and therefore, their systemic performances in the environmental and cost spheres have also become essential requirements. This study proposed corroborating this trend, analyzing the available literature on the subject to verify how experts in the AOP area investigated this integration during 2015-2023. For this purpose, a sample of publications was treated by applying the Systematic Review (SR) methodology. This resulted in an extract of 83 studies that adopted life-cycle logic to estimate environmental impacts and process costs or evaluated them as complementary to the technical dimension of each treatment technology. This analysis found that both dimensions can be used for selecting or sizing AOPs at the design scale. However, the appropriate choice of the impact categories for the environmental assessment and establishing a methodology for cost analysis can make the approach still more effective. In addition, a staggering number of processes would broaden the reality and applicability of the estimates, and adopting multicriteria analysis methodologies could address essential aspects of decision-making processes during the design of the arrangements. By meeting the original purposes, the study broadened the requirements for designing AOPs and disseminating their use in mitigating the discharge of CECs.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Animais , Poluentes Químicos da Água/análise , Oxirredução , Meio Ambiente , Purificação da Água/métodos , Bibliometria , Estágios do Ciclo de Vida
4.
Artigo em Inglês | MEDLINE | ID: mdl-38472580

RESUMO

Herein, we explore the holistic integration of magnetite-based photocatalysts and techno-economic analysis (TEA) as a sustainable approach in wastewater treatment aligned with the Sustainable Development Goals (SDGs). While considerable attention has been devoted to photocatalytic dye degradation, the nexus between these processes and techno-economic considerations remains relatively unexplored. The review comprehensively examines the fundamental characteristics of magnetite-based photocatalysts, encompassing synthesis methods, composition, and unique properties. It investigates their efficacy in photocatalytic degradation, addressing homogeneous and heterogeneous aspects while discussing strategies to optimize photodegradation efficiency, including curbing electron-hole recombination and mitigating scavenging effects and interference by ions and humic acid. Moreover, the management aspects of magnetite-based photocatalysts are examined, focusing on their reusability and regeneration post-dye removal, along with the potential for reusing treated wastewater in relevant industrial applications. From a techno-economic perspective, the study evaluates the financial feasibility of deploying magnetite-based photocatalysts in wastewater treatment, correlating reduced pollution and the marketing of treated water with social, economic, and environmental objectives. By advocating the integration of magnetite-based photocatalysts and TEA, this paper contributes insights into scalable and profitable sustainable wastewater treatment practices. It underscores the alignment of these practices with SDGs, emphasizing a comprehensive and holistic approach to managing wastewater in ways that meet environmental, economic, and societal objectives.

5.
Surv Ophthalmol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492584

RESUMO

Artificial Intelligence (AI) has become a focus of research in the rapidly evolving field of ophthalmology. Nevertheless, there is a lack of systematic studies on the health economics of AI in this field. We examine studies from the PubMed, Google Scholar, and Web of Science databases that employed quantitative analysis, retrieved up to July 2023. Most of the studies indicate that AI leads to cost savings and improved efficiency in ophthalmology. On the other hand, some studies suggest that using AI in healthcare may raise costs for patients, especially when taking into account factors such as labor costs, infrastructure, and patient adherence. Future research should cover a wider range of ophthalmic diseases beyond common eye conditions. Moreover, conducting extensive health economic research, designed to collect data relevant to its own context, is imperative.

6.
Environ Sci Technol ; 58(11): 4957-4967, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38446013

RESUMO

Electrification and clean hydrogen are promising low-carbon options for decarbonizing industrial process heat, which is an essential target for reducing sector-wide emissions. However, industrial processes with heat demand vary significantly across industries in terms of temperature requirements, capacities, and equipment, making it challenging to determine applications for low-carbon technologies that are technically and economically feasible. In this analysis, we develop a framework for evaluating life cycle emissions, water use, and cost impacts of electric and clean hydrogen process heat technologies and apply it in several case studies for plastics and petrochemical manufacturing industries in the United States. Our results show that industrial heat pumps could reduce emissions by 12-17% in a typical poly(vinyl chloride) (PVC) facility in certain locations currently, compared to conventional natural gas combustion, and that other electric technologies in PVC and ethylene production could reduce emissions by nearly 90% with a sufficiently decarbonized electric grid. Life cycle water use increases significantly in all low-carbon technology cases. The levelized cost of heat of viable low-carbon technologies ranges from 15 to 100% higher than conventional heating systems, primarily due to energy costs. We discuss results in the context of relevant policies that could be useful to manufacturing facilities and policymakers for aiding the transition to low-carbon process heat technologies.


Assuntos
Cloreto de Vinil , Estados Unidos , Temperatura Alta , Carbono , Instalações Industriais e de Manufatura , Etilenos , Hidrogênio , Água
7.
J Environ Manage ; 355: 120525, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38437743

RESUMO

Activated carbon (AC), renowned for its versatile applications in water treatment, air purification, and industrial processes, is a critical component in environmental remediation and resource recovery strategies. This study encompasses the process modeling of AC production using anthracite coal as a precursor, involving multiple activation stages at different operating conditions, coupled with a detailed techno-economic analysis aimed at assessing the operational feasibility and financial viability of the plant. The economic analysis explores the investigation of economic feasibility by performing a detailed cashflow and sensitivity analysis to identify key parameters influencing the plant's economic performance, including raw material and energy prices, operational and process parameters. Capital and operational costs are meticulously evaluated, encompassing raw material acquisition, labor, energy consumption, and equipment investment. Financial metrics like Net Present Value (NPV), Internal Rate of Return (IRR), and payout period (POP) are employed, and the results show that AC selling price, raw material cost and plant capacity are the most influential parameters determining the plant's feasibility. The minimum AC production cost of 1.28 $/kg is obtained, corresponding to coal flow rate of 14,550 kg/h. These findings provide valuable insights for stakeholders, policymakers, and investors seeking to engage in activated carbon production from anthracite.


Assuntos
Carvão Vegetal , Recuperação e Remediação Ambiental , Carvão Mineral , Investimentos em Saúde , Plantas
8.
Orthop Traumatol Surg Res ; : 103852, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38428486

RESUMO

INTRODUCTION: This study aimed to assess cost-effectiveness of shoulder arthroplasty for osteoarthritis (OA) and rotator cuff tear arthropathy (CTA) from the perspective of a publicly funded health care system using patient data, health utilities and costs from a real-world situation. HYPOTHESIS: Our hypothesis was that arthroplasty for OA is more cost-effective than for CTA. MATERIAL AND METHODS: We gathered a cohort of patients with 153 anatomic total shoulder arthroplasty (TSA) for OA and 107 reverse shoulder arthroplasty (RSA) for CTA between years 2016-2020 at a university hospital. Short-term (mean 2.8years) shoulder function, health utilities and costs were obtained from prospectively collected data, and a Markov cohort simulation was carried out to assess lifetime cost-utility. The primary outcome measures were change in 15D score to calculate gain in quality-adjusted life years (QALYs) and change in Western Ontario osteoarthritis score of the shoulder (WOOS). RESULTS: Both TSA and RSA restored shoulder function well, WOOS improvement was 59.7 (95% CI: 56.2-63.2) and 55.8 (95% CI: 50.4-61.2), respectively. The cost/QALY gained was 20,846.82 € for TSA and 38,711.90 € for RSA. The cost-utility was not remarkable sensitive to costs, discounting of future costs or estimated revision rates. However, the cost-effectiveness was very sensitive to change in 15D health utility scores and thus QALY gain, especially for RSA patients. DISCUSSION: Shoulder arthroplasty restores shoulder function well in both OA and CTA. In health economic terms, RSA is less cost-effective than TSA in an everyday setting, mainly due to inferior improvement of health-related quality-of-life and reduced life expectancy of CTA patients. LEVEL OF EVIDENCE: III; case series.

9.
Hum Reprod ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438132

RESUMO

STUDY QUESTION: Which assited reproductive technology (ART) interventions in high-income countries are cost-effective and which are not? SUMMARY ANSWER: Among all ART interventions assessed in economic evaluations, most high-cost interventions, including preimplantation genetic testing for aneuploidy (PGT-A) for a general population and ICSI for unexplained infertility, are unlikely to be cost-effective owing to minimal or no increase in effectiveness. WHAT IS KNOWN ALREADY: Approaches to reduce costs in order to increase access have been identified as a research priority for future infertility research. There has been an increasing number of ART interventions implemented in routine clinical practice globally, before robust assessments of evidence on economic evaluations. The extent of clinical effectiveness of some studied comparisons has been evaluated in high-quality research, allowing more informative decision making around cost-effectiveness. STUDY DESIGN, SIZE, DURATION: We performed a systematic review and searched seven databases (MEDLINE, PUBMED, EMBASE, COCHRANE, ECONLIT, SCOPUS, and CINAHL) for studies examining ART interventions for infertility together with an economic evaluation component (cost-effectiveness, cost-benefit, cost-utility, or cost-minimization assessment), in high-income countries, published since January 2011. The last search was 22 June 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two independent reviewers assessed publications and included those fulfilling the eligibility criteria. Studies were examined to assess the cost-effectiveness of the studied intervention, as well as the reporting quality of the study. The chosen outcome measure and payer perspective were also noted. Completeness of reporting was assessed against the Consolidated Health Economic Evaluation Reporting Standard. Results are presented and summarized based on the intervention studied. MAIN RESULTS AND THE ROLE OF CHANCE: The review included 40 studies which were conducted in 11 high-income countries. Most studies (n = 34) included a cost-effectiveness analysis. ART interventions included medication or strategies for controlled ovarian stimulation (n = 15), IVF (n = 9), PGT-A (n = 7), single embryo transfer (n = 5), ICSI (n = 3), and freeze-all embryo transfer (n = 1). Live birth was the mostly commonly reported primary outcome (n = 27), and quality-adjusted life years was reported in three studies. The health funder perspective was used in 85% (n = 34) of studies. None of the included studies measured patient preference for treatment. It remains uncertain whether PGT-A improves pregnancy rates compared to IVF cycles managed without PGT-A, and therefore cost-effectiveness could not be demonstrated for this intervention. Similarly, ICSI in non-male factor infertility appears not to be clinically effective compared to standard fertilization in an IVF cycle and is therefore not cost-effective. Interventions such as use of biosimilars or HMG for ovarian stimulation are cheaper but compromise clinical effectiveness. LIMITATIONS, REASONS FOR CAUTION: Lack of both preference-based and standardized outcomes limits the comparability of results across studies. The selection of efficacy evidence offered for some interventions for economic evaluations is not always based on high-quality randomized trials and systematic reviews. In addition, there is insufficient knowledge of the willingness to pay thresholds of individuals and state funders for treatment of infertility. There is variable quality of reporting scores, which might increase uncertainty around the cost-effectiveness results. WIDER IMPLICATIONS OF THE FINDINGS: Investment in strategies to help infertile people who utilize ART is justifiable at both personal and population levels. This systematic review may assist ART funders decide how to best invest to maximize the likelihood of delivery of a healthy child. STUDY FUNDING/COMPETING INTEREST(S): There was no funding for this study. E.C. and R.W. receive salary support from the National Health and Medical Research Council (NHMRC) through their fellowship scheme (EC GNT1159536, RW 2021/GNT2009767). M.D.-T. reports consulting fees from King Fahad Medical School. All other authors have no competing interests to declare. REGISTRATION NUMBER: Prospero CRD42021261537.

10.
Stereotact Funct Neurosurg ; : 1-17, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513625

RESUMO

INTRODUCTION: Despite the known benefits of deep brain stimulation (DBS), the cost of the procedure can limit access and can vary widely. Our aim was to conduct a systematic review of the reported costs associated with DBS, as well as the variability in reporting cost-associated factors to ultimately increase patient access to this therapy. METHODS: A systematic review of the literature for cost of DBS treatment was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed and Embase databases were queried. Olsen & Associates (OANDA) was used to convert all reported rates to USD. Cost was corrected for inflation using the US Bureau of Labor Statistics Inflation Calculator, correcting to April 2022. RESULTS: Twenty-six articles on the cost of DBS surgery from 2001 to 2021 were included. The median number of patients across studies was 193, the mean reported age was 60.5 ± 5.6 years, and median female prevalence was 38.9%. The inflation- and currency-adjusted mean cost of the DBS device was USD 21,496.07 ± USD 8,944.16, the cost of surgery alone was USD 14,685.22 ± USD 8,479.66, the total cost of surgery was USD 40,942.85 ± USD 17,987.43, and the total cost of treatment until 1 year of follow-up was USD 47,632.27 ± USD 23,067.08. There were no differences in costs observed across surgical indication or country. CONCLUSION: Our report describes the large variation in DBS costs and the manner of reporting costs. The current lack of standardization impedes productive discourse as comparisons are hindered by both geographic and chronological variations. Emphasis should be put on standardized reporting and analysis of reimbursement costs to better assess the variability of DBS-associated costs in order to make this procedure more cost-effective and address areas for improvement to increase patient access to DBS.

11.
Bioresour Technol ; 399: 130572, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492651

RESUMO

Aqueous phase reforming has been explored for renewable H2 production from waste biomass. Promising results have been reported for pyrolysis bio-oil aqueous fractions (AFB), but economical assessments are needed to determine process feasibility, which requires both energy consumption minimization and optimal H2 valorization. This work compares different alternatives using process simulation and economic evaluation computational tools. Experimental results and a specific thermodynamic model are used to set mass balances. An adequate heat integration allows to reduce the process energy demand, covering the 100 % of the reactor duty. Optimal H2 unit cost is achieved if part of the produced H2 is valorized for energy self-covering and the rest is commercialized. Renewable H2 net production of c.a. 3.3 kgH2/m3 of treated AFB at a preliminary 1-2 €/kg unit cost is estimated, which can be considered as competitive with green H2, even though a case of diluted AFB is considered.


Assuntos
Hidrogênio , Polifenóis , Pirólise , Rios , Óleos de Plantas , Água , Biomassa
12.
Environ Sci Technol ; 58(8): 3823-3829, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38366998

RESUMO

Despite the large carbon footprint of livestock production, animal protein consumption has grown over the past several decades, necessitating new approaches to sustainable animal protein production. In this techno-economic analysis, single cell protein (SCP) produced via gas fermentation of carbon dioxide, oxygen, and hydrogen is studied as an animal feed source to replace fishmeal or soybean meal. Using wind-powered water electrolysis to produce hydrogen and oxygen with carbon dioxide captured from corn ethanol, the minimum selling price (MSP) of SCP is determined to be $2070 per metric ton. An emissions comparison between SCP, fishmeal, and soybean meal shows that SCP has a carbon intensity as low as 0.73 kg CO2-equiv/kg protein, while fishmeal and soybean meal have an average carbon intensity of 2.72 kg CO2-equiv/kg protein and 0.85 kg CO2-equiv/kg protein, respectively. Moreover, SCP production would occupy 0.4% of the land per ton of protein produced compared to soybean meal and would disturb less than 0.1% of the marine ecosystem currently disturbed by fishmeal harvesting practices. These results show promise for the future economic viability of SCP as a protein source in animal feed and indicate significant environmental benefits compared to other animal feed protein sources.


Assuntos
Dióxido de Carbono , Proteínas na Dieta , Ecossistema , Animais , Fermentação , Soja , Hidrogênio , Oxigênio
13.
Bioresour Technol ; 397: 130456, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369081

RESUMO

Microorganisms, such as yeasts, filamentous fungi, bacteria, and microalgae, have gained significant attention due to their potential in producing commercially valuable natural carotenoids. In recent years, Phaffia rhodozyma yeasts have emerged as intriguing non-conventional sources of carotenoids, particularly astaxanthin and ß-carotene. However, the shift from academic exploration to effective industrial implementation has been challenging to achieve. This study aims to bridge this gap by assessing various scenarios for carotenoid production and recovery. It explores the use of ionic liquids (ILs) and bio-based solvents (ethanol) to ensure safe extraction. The evaluation includes a comprehensive analysis involving Life Cycle Assessment (LCA), biocompatibility assessment, and Techno-Economic Analysis (TEA) of two integrated technologies that utilize choline-based ILs and ethanol (EtOH) for astaxanthin (+ß-carotene) recovery from P. rhodozyma cells. This work evaluates the potential sustainability of integrating these alternative solvents within a yeast-based bioeconomy.


Assuntos
Basidiomycota , beta Caroteno , Saccharomyces cerevisiae , Carotenoides , Etanol , Solventes , Xantofilas
14.
Environ Sci Pollut Res Int ; 31(13): 19244-19256, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38355862

RESUMO

Solar water heaters are a type of renewable energy technology that converts solar energy into heat to warm water. Solar water heaters are becoming increasingly popular due to their eco-friendliness, cost-effectiveness, and low maintenance requirements. In this study, low-cost solar collectors were developed using date palm waste (dried leaves) as thermal insulation. Date palm waste is a readily available and abundant resource in many regions, and using it in solar collectors can help reduce waste and promote sustainability. Two solar collectors were fabricated using crushed date palm waste, with one collector using the waste alone and the other mixed with starch. Tests were conducted in accordance with the European standard EN 12975-2-2006 and modeled the thermal behavior of the collectors. The results obtained showed that the prototypes of solar collectors performed well and exhibited behavior comparable to that of a commercial solar collector, with a production cost up to three times less. The use of date palm waste as thermal insulation in solar collectors is an innovative approach that aligns with the principles of sustainability and environmental friendliness. Furthermore, it was found that the leveled heating cost (LCOH) and the simple payback period (SPP) were 0.952 US$ kWh-1 and 2.472 years for the prototype without starch and 0.926 US$ kWh-1 and 2.397 years for the prototype with starch.


Assuntos
Phoeniceae , Energia Solar , Água , Amido , Luz Solar
15.
Int J Biol Macromol ; 263(Pt 1): 130253, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368976

RESUMO

This study involves the synthesis of a magnetic­sodium alginate bio-composite embedded with carbon dots, designed to eliminate pollutants like dyes and metal ions and tackle environmental issues. The modified particles are effectively incorporated into the biopolymers for improved adsorption and regeneration performance using an economically viable and environmentally sustainable process. The composite's surface morphology and chemical structure have been extensively characterized through various analytical techniques. It has been found that CD-modified nanoparticles demonstrate good dispersion, abundance in functional groups, and excellent adsorption performance. The adsorption process variables have been optimized using Response Surface Methodology (RSM), resulting in a maximum adsorption capacity of 232.44 mg/g achieved under optimal conditions. An Artificial Neural Network (ANN) model with a topology of 3-5-5-1 is constructed to predict the adsorption capacity of composite, exhibiting superior predictive performance. The statistical physical model was also performed to understand the adsorption mechanism and orientation of dye molecules attached to the surface of the composite. The adsorption capacity using statistical physical method was found to be 467.57 mg/g. The composite exhibits good adsorption and regeneration performance in the column adsorption study. Furthermore, a detailed cost analysis of the synthesized composite was performed, ensuring its economic viability in real-world applications.


Assuntos
Carbono , Poluentes Químicos da Água , Alginatos/química , Água , Corantes , Adsorção , Redes Neurais de Computação , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
16.
Artigo em Inglês | MEDLINE | ID: mdl-38308804

RESUMO

INTRODUCTION: Familial hypercholesterolemia is a common genetic condition that significantly increases an individual's risk of cardiovascular events such as heart attack, stroke, and cardiac death and is a candidate for population-wide screening programs. Economic analyses of strategies to identify and treat familial hypercholesterolemia are limited by a lack of real-world cost estimates for screening services and medications for reducing cardiovascular risk in this population. METHODS: We estimated the cost of lipid panel testing in patients with hyperlipidemia and the cost of statins, ezetimibe, and PCKS9 inhibitors in patients with familial hypercholesterolemia from a commercial claims database and report costs and charges per panel and prescription by days' supply. RESULTS: The mean cost for a 90-day supply for statins was $183.33, 2.3 times the mean cost for a 30-day supply at $79.35. PCSK9 inhibitors generated the highest mean costs among medications used by patients with familial hypercholesterolemia. CONCLUSIONS: Lipid testing and lipid-lowering medications for cardiovascular disease prevention generate substantial real-world costs which can be used to improve cost-effectiveness models of familial hypercholesterolemia screening and care management.

17.
Heliyon ; 10(4): e26084, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390131

RESUMO

Pumps as Turbines (PATs) are known for their ability to replace conventional turbines in Pico/micro-hydropower plants. However, selecting a suitable pump and estimating its performance in reverse mode is a challenging task. The overall efficiency of PATs is also lower when compared to purpose-made turbines. Numerous attempts have been made to analyze the performance of PAT in power-generating applications, and many scholars have presented their research on performance improvement and economic analysis. In this paper, a detailed review is conducted to show the historical development and current status of PAT technology. The review also presents the findings of performance prediction, performance improvement techniques, and economic analysis. The results of the literature survey demonstrate that the choice of an appropriate pump for a specific application significantly affects the performance of the PAT system. Among the various options, the Shear Stress Transport (SST) k-ω and standard k-ε turbulence models are widely used for simulating the pump as a turbine. Blade grooving and blade tip rounding are recognized as the most promising techniques for improving efficiency, with gains of 4.91% and 4.00%, respectively. Except for impeller diameter trimming, blade modification techniques proposed by various scholars have a significant impact on the efficiency of PATs; however, further research is needed to investigate the economic advantages of impeller modification.

18.
Environ Sci Ecotechnol ; 21: 100395, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38357481

RESUMO

China is the largest coke producer and consumer. There is a pressing need to address the high emissions of air pollutants and carbon dioxide associated with traditional coking production. As the nation pursues a transition towards carbon neutrality, expanding supply chains for coking plants to produce hydrogen, methanol, and other green alternatives has garnered significant attention. However, the relative advantages of these strategies have remained uncertain. In this study, we integrate a life cycle assessment-economic analysis-scenario analysis model to evaluate various coke oven gas (COG) utilization routes (COGtM: COG-to-methanol, COGtLNG: COG-to-liquefied natural gas, COGtSA: COG-to-synthetic ammonia, and COGtH: COG-to-hydrogen). The results indicate that COGtSA emerges as the preferred option for balancing environmental and economic benefits. Meanwhile, COGtM demonstrates economic viability but is associated with higher environmental impacts. Despite being recognized as a significant strategic direction under carbon neutrality initiatives, COGtH faces economic feasibility and risk resilience limitations. COGtLNG encounters both financial and environmental challenges, necessitating strategic development from an energy security perspective. The projected coking capacity is anticipated to experience a slight increase in the mid-term yet a significant decline in the long term, influenced by steel production capacity. In potential future markets, COGtM is estimated to potentially capture a maximum market share of 16-34% in the methanol market. Furthermore, against the backdrop of continuously expanding potential demand for hydrogen, COGtH holds advantages as a transitional solution, but in the long run, it can only meet a small portion of the market. COGtSA can meet 7-14% of market demand and emerges as the most viable pathway from the viewpoint of balancing environmental and economic aspects and covering future markets.

19.
Food Sci Nutr ; 12(2): 952-970, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38370039

RESUMO

Postharvest losses (PHLs) of biomaterials, such as vegetables and fruits, significantly impact food security and economic stability in developing nations. In Tanzania, PHLs are estimated to range between 30% and 40% for cereal crops and even higher for perishable crops such as fruits and vegetables. Open-sun drying (OSD) is the most extensively employed method because of its affordability and simplicity. However, OSD has several drawbacks, including difficulties in managing drying parameters, long drying times owing to adverse weather, and product contamination. The solar-assisted heat pump dryer (SAHPD) is a technology designed as an alternative solution for drying biomaterials and reducing PHL. A limited number of SAHPDs have been constructed in developing nations. Most of the works have concentrated on the performance analysis of the systems. This neglects the techno-economic assessment, which is important to provide both a quantitative and qualitative understanding of the financial viability of the technology. The present study therefore investigates the techno-economic analysis of a novel SAHPD for drying agricultural products, particularly vegetables and fruits. To determine whether the SAHPD technology is technically and economically viable, tomatoes and carrots were dried and analyzed to determine their thermal and economic performance. The results show that the initial moisture contents of tomatoes (Lycopersicum esculentum) and carrots (Daucus carota) were reduced from 93% and 88% to 10% in 11 and 12 h, respectively. The coefficient of performance (COP), drying time (DT), specific moisture extraction ration (SMER) and thermal efficiency (ηT) were found to be 3.4, 2.3 kg/h, 1.33 kg/kWh and 54.0%, respectively. The economic analysis was assessed using the annualized cost, lifecycle savings, and payback period for the dryer's life span of 15 years. The initial investment of the SAHPD was $5221.8 and the annualized cost was $1076.5. The cumulative present worth for 15 years was found to be $23,828.8 and $27,553.1 for tomatoes and carrots, respectively. The payback period for tomatoes was found to be 3 years, whereas for carrots it was 2.6 years. Based on thermal and economic performance assessment results, the developed SAHPD is technically and economically viable to be considered for further investments.

20.
Clinicoecon Outcomes Res ; 16: 81-96, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374959

RESUMO

Background: As healthcare costs are increasingly being shifted from payers to patients, it is important to understand the economic consequences of therapeutic strategies to both payers and patients. Objective: To determine the relative costs to Medicare and Medicare beneficiaries (patients) of warfarin, non-vitamin K oral anticoagulants (NOACs), and left atrial appendage closure (LAAC) for stroke risk reduction in nonvalvular atrial fibrillation. Methods: An economic model was developed to assess costs at 5 and 10 years. For warfarin and NOACs, inputs were derived from published meta-analyses; for LAAC with the Watchman device, inputs were derived from pooled 5-year PROTECT AF and PREVAIL trial results. The model captured therapy costs vs clinical event costs, including procedural complications and follow-up clinical outcomes. Costs were based on 2023 Medicare reimbursement and copayment rates. Results: At 10 years, overall LAAC costs ($48,337) were lower than those of NOACs ($81,198) and warfarin ($52,359). Overall LAAC costs were lower than those of NOACs by year 5 and warfarin by year 9. At 5 years, patient LAAC costs were lowest at $4,764, compared to $7,146 and $6,453 for NOACs and warfarin, respectively. LAAC patient costs were lower than those of NOACs by year 3 and warfarin by year 4. Clinical events comprised 96% of overall warfarin costs vs 48% for LAAC and 40% for NOACs. Conclusion: LAAC yielded the lowest overall and patient costs. Warfarin costs were largely driven by clinical events, which may represent an unplanned financial burden for patients. These considerations should be incorporated into shared decision-making discussions about stroke prophylaxis strategies.

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