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For papers to have scientific impact, they need to impress our peers in their role as referees, journal editors, and members of conference committees. Does better writing help our papers make it past these gatekeepers? In this study, we estimate the effect of writing quality by comparing how 30 economists judge the quality of papers written by PhD students in economics. Each economist judged five papers in their original version and five different papers that had been language edited. No economist saw both versions of the same paper. Our results show that writing matters. Compared to the original versions, economists judge edited versions as higher quality; they are more likely to accept edited versions for a conference; and they believe that edited versions have a better chance of being accepted at a good journal. [ABSTRACT FROM AUTHOR]

This paper introduces a type of circular causation called Congestive Mode-Switching (CMS) that may arise when an increase in congestion penalizes transit relative to driving. In turn, rising congestion persuades some transit riders to drive, which exacerbates congestion further, and so on. This circular causation can beget multiple equilibria with different levels of congestion and transit ridership. The paper explores this logic with a static model of a bus route. When the bus fleet size is fixed, CMS applies because congestion raises the bus cycle time and thus lowers bus frequency, resulting in higher wait times. When the fleet size depends on bus ridership, CMS is joined by economies of scale as a second source of circular causation. We derive the system's equilibria using a static model in the vein of Walters (1961), which permits us to graphically characterize equilibria in useful ways. The comparative statics of a road improvement show how feedback alters first-order effects. A Downs-Thomson paradox is not possible, because a road improvement aids buses even more than cars. Continuous-time stability analysis shows that multiple equilibria may be stable. • Introduces a type of circular causation for mixed-traffic transit systems called Congestive Mode-Switching (CMS). • Shows CMS can lead to multiple equilibria in a model of a bus route with mode choice. • Characterizes comparative statics and stability of equilibria. • Shows how CMS interacts with economies of scale, another source of circular causation. [ABSTRACT FROM AUTHOR]

Decision makers are increasingly requesting that environmental and climate drivers be included in stock assessments and subsequent projections that provide managers with advice on the consequences of applying harvest control rules. Another key direction in stock assessment science is to capture the full range of uncertainty (model, process, and estimation). However, multiple sources of uncertainty are rarely accounted for when conducting projections based on environmental and climate drivers. We describe a framework for conducting projections that allows for structural model uncertainty (in the structure of the population dynamics model on which the assessment is based, and the Earth System Models and emission scenarios used to drive future recruitment and growth), for process error in future recruitment, and for uncertainty in the parameter estimates of the population dynamics model. We then apply the framework to data for Pacific cod, Gadus macrocephalus , in the eastern Bering Sea, with projections based on a harvest control rule that attempts to maximize the difference between revenue and variable costs based on the current growth and recruitment dynamics of the stock. Increases in temperature are found to increase weight-at-age but reduce recruitment. However, the negative effects on recruitment outweigh the positive effects on weight-at-age. In many cases, the harvest control rules considered in this paper, particularly those based on the assumption of no future environmental effects on population parameters, fail to conserve the stock if the inferred catch limits are taken, which suggests that declines in biomass and catch will take place if the current harvest control rules continue to be used. The strategies that lead to reductions in catch and biomass also lead to much lower profits for the fishery, particularly over the long-term. However, basing future catches on the environmental scenario that leads to the poorest outcomes (GFDL ssp585) generally keeps the stock above the threshold of 20 % of unfished spawning biomass under most climate scenarios and also achieves long-term profits at or greater than those expected in the next ten years. [ABSTRACT FROM AUTHOR]

Studies of transit dwell times suggest that the delay caused by passengers boarding and alighting rises with the number of passengers on each vehicle. This paper incorporates such a "friction effect" into an isotropic model of a transit route with elastic demand. We derive a strongly unimodal "Network Alighting Function" giving the steady-state rate of passenger flows in terms of the accumulation of passengers on vehicles. Like the Network Exit Function developed for isotropic models of vehicle traffic, the system may exhibit hypercongestion. Since ridership depends on travel times, wait times and the level of crowding, the physical model is used to solve for (possibly multiple) equilibria as well as the social optimum. Using replicator dynamics to describe the evolution of demand, we also investigate the asymptotic local stability of different kinds of equilibria. • Incorporates "friction effects" into an isotropic model of a transit route. • Derives a strongly unimodal Network Alighting Function with hypercongested states. • The route exhibits multiple equilibria for a given fare and fleet size. • Derives optimal fares and fleet size. • Investigates the local asymptotic stability of equilibria. [ABSTRACT FROM AUTHOR]

• Alkaline Water Electrolysis functions best between 65 and 100 °C at 2–10 bar pressure. • Solid Oxide Electrolysis Cells operate at higher temperatures of 600–1200 °C. • Proton exchange membrane electrolyzers work at current densities >2 A cm−2. • Transition metal-based catalysts demonstrate high performance for HER and OER. • Photocatalysts such as Zn 0.5 Cd 0.5 S/Ti 2 C/TiO 2 have excellent catalytic activity. Hydrogen energy is essential to building a sustainable society with net zero carbon emissions in the face of global climate change and the energy revolution. Hydrogen generation begins with most Power-to-X methods that shape the future energy market. Electrolysis systems that use water/steam to make hydrogen have their own benefits and downsides. Electrolysis and photocatalysis are the main water-splitting methods employed to produce hydrogen. This study outlines these technologies and their future problems and potential. The literature suggests that Alkaline Water Electrolysis (AWE) is a commercial technology that can produce hydrogen on a large scale, whereas Proton Exchange Membrane Electrolysis (PEME) and Solid Oxide Electrolysis Cells (SOEC) are very efficient. Energy-efficient and economically feasible water electrolysis face several challenges. It requires effective, long-lasting catalysts to boost Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) efficiency. This publication includes a table of electrocatalyst groups. Transition metal catalysts are cheaper and as efficient as noble metal catalysts such as IrO 2 , RuO 2 , Pt, and Pd. It also highlights the challenges of electrocatalyst industrialization and commercialization and suggests solutions. The latter half of the paper reviews photocatalysis as an efficient method to produce hydrogen. It also discusses photocatalysts developed to increase H 2 production efficiency. The photocatalytic water splitting activity of pure photocatalysts is enhanced by manipulating morphology, cationic/anionic doping, heterojunction/nanocomposite constructions, and defect formation. The report also covers other alternative renewable energy sources for hydrogen generation. [ABSTRACT FROM AUTHOR]

Microalgae are a source of a range of natural products, including biofuels, but financial and technical limitations can make large-scale production challenging to commercialize. A significant limitation is the practical and economical bulk harvesting of microalgae from the cultivation medium. Based on chemical and energy demands, common harvesting processes can have high costs due to microalgae having a similar specific gravity as their medium, negative surface charges and significant variability between strains. Determining the cost-effectiveness of harvesting methods is complicated as many publications commonly quote harvesting as costing 20–30 % of the operational cost, regardless of the method of biomass production (e.g., open ponds, bioreactors, etc.) or the harvesting method selected. This non-specific statement does not reflect that specific harvesting methods will have different operational costs. This paper aims to provide a more accurate, method-specific cost analysis of the harvesting stage operating costs to help in the economic analysis of microalgae production systems. The four primary harvesting mechanisms currently used, centrifugation, flocculation, flotation, and filtration, are assessed for their energy and chemical consumption. Centrifugation, flocculation, flotation, and filtration had an average biomass recovery of 92 %, 95 %, 92 % and 91 % and an energy requirement range of 1–8 kWh m−3, 0.1–6.7 kWh m−3, 0.015–7.6 kWh m−3 and 0.1–5.9 kWh m−3, respectively. Furthermore, the operational costs, based on energy requirements and the use of flocculants, were 0.448–1.086 USD m−3, 0.014–16.65 USD m−3, 0.08–31.3 USD m−3 and 0.013–0.791 USD m−3, respectively. Finally, the biomass production costs were calculated as ranging between 0.02–0.177 USD kg−1, 0.006–35.05 USD kg−1, 0.169–26.95 USD kg−1 and 0.02–3.00 USD kg−1 for centrifugation, flocculation, flotation, and filtration microalgae harvesting technologies, respectively. [Display omitted] • Microalgae harvesting is often quoted as a generic 20–30 % of total production costs. • Harvesting options are centrifugation, flocculation, flotation, and filtration. • Harvesting economics are based on processing time, energy and chemical requirements. • Chemical harvesting has lower energy requirements, but often requires flocculants. [ABSTRACT FROM AUTHOR]

Governments and the food industry make major efforts to ensure food safety throughout the global supply chain and support food availability. Experiences with Coronavirus disease 2019 (COVID-19) have re-emphasized the need for preparedness in many sectors, including the food sector. This position paper analyzes the potential introduction and transmission of pandemic viruses via the food chain and hypothesizes which new food safety issues could arise. Two scenarios, a gastrointestinal virus and a respiratory virus, were explored. Possible risks and economic costs of introduction and transmission, regulatory and analytical needs, and control strategies associated with such scenarios are described. Overall, if a pandemic virus associated with the food chain was to occur, our preparedness is currently lacking given our potentially limited knowledge of introduction and transmission pathways, as well as access to methods to detect the viral presence and infectivity and model the transmission of the pathogens, even though the economic and societal impact of such a scenario is likely extensive. The food and fomite component could be easily neglected or underestimated in a future pandemic. On the other hand, better tools to prove the lack of food chain transmissibility of a pandemic virus could also prevent unnecessary economic losses across the sector. In the event of a foodborne pandemic virus, food safety testing would provide a clear purpose to detect deviating batches, obtain monitoring data, and assess compliance to hygiene criteria; however, providing complete safety through enforcement criteria is demonstrated to be economically unfeasible; therefore, other control interventions will be needed. These messages are important for food business operators and governments to understand the possible analytical needs, opportunities, and caveats for food safety testing. Narrowing the knowledge gaps on introduction and transmission, and improvement of analytical feasibility is required to benefit our preparedness against the emergence and spread of future foodborne pandemic pathogens. • Knowledge of the transmission and introduction of viruses via food is incomplete. • Current methods to detect and model viral presence and infectivity are limited. • The economic impact of a pandemic food-borne virus would be extensive. • The role of food and fomites in future pandemics may be underestimated. • Food safety testing has limitations; other control interventions will be needed. [ABSTRACT FROM AUTHOR]

For a static economic model of auto traffic in an isotropic zone, this paper classifies possible equilibria into three types, by whether traffic is hypercongested and by the relative slopes of "supply" and "demand" curves. We then conduct a local stability analysis of each type when density, demand and the unit travel time (inverse speed) evolve gradually and simultaneously according to dynamical systems of differential equations. Some hypercongested equilibria may be stable when demand adjusts quickly enough to congestion. Other hypercongested equilibria, which have counterintuitive comparative statics, are never stable. Non-hypercongested equilibria can be unstable under special circumstances. A discrete event simulation with a dynamic Poisson arrival process supports the results of the formal analysis. • Examines equilibrium stability for a static model of traffic in an isotropic zone with elastic demand. • Builds autonomous systems governing how density, demand and speed adjust. • Some hypercongested equilibria can be stable if demand adjusts quickly enough. • Non-hypercongested equilibria can be unstable under special circumstances. • Validates results using a trip-based simulation with a dynamic Poisson arrival process. [ABSTRACT FROM AUTHOR]