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Food supply chains hold significant embodied carbon emissions that need to be mitigated and neutralized. This study aimed to explore the historical Greenhouse Gas (GHG) emissions associated with household food consumption at a local scale i.e. across the eight English regions and the four nations that comprise the United Kingdom (UK). UK EatWell guidelines were used to explore the potential change in emissions and food costs in a scenario of transitions to healthier diets across the study areas. These emissions were calculated based on food consumption data before the advent of the Covid-pandemic i.e. between the years 2001 and 2018. Spatial data analysis was used to explore if the study areas had any significant correlations with respect to the emissions during the study period. The results displayed a potential reduction in GHG emissions for all study areas in the explored scenario. Further impacts include a reduction in household food costs across a majority of the areas during the study period. However, a consistent trend of significant correlations among the study areas was absent. This study concludes that local or regional policymaking should take precedence over national regulations to achieve healthier diets that are both carbon-neutral and affordable for the households. [ABSTRACT FROM AUTHOR]

In the West, limited government capacity to solve environmental problems has triggered the rise of a variety of "nonstate actors" to supplement government efforts or provide alternative mechanisms for addressing environmental issues. How does this development - along with our efforts to understand it - map onto environmental governance processes in China? China's efforts to address environmental issues reflect institutionalized governance processes that differ from parallel western processes in ways that have major consequences for domestic environmental governance practices and the governance of China "going abroad." China's governance processes blur the distinction between the state and other actors; the "shadow of the state" is a major factor in all efforts to address environmental issues. The space occupied by nonstate actors in western systems is occupied by shiye danwei ("public service units"), she hui tuanti ("social associations") and e-platforms, all of which have close links to the state. Meanwhile, international NGOs and multinational corporations are also significant players in China. As a result, the mechanisms of influence that produce effects in China differ in important ways from mechanisms familiar from the western experience. This conclusion has far-reaching implications for those seeking to address global environmental concerns, given the importance of China's growing economy and burgeoning network of trade relationships.

Purpose: This research aims to discover the relationship between social media usage (SMU) and the critical thinking ability (CTA) of university students, and to answer the question that whether social media dependence (SMD) affects the development of CTA, and thus providing a reference for the social media access strategy of academic libraries from the perspective of media information literacy. Design/methodology/approach: The research data were collected via 300 valid questionnaires whose respondents are students from three universities in China. Multistage stratified cluster sampling method was used to select the respondents, which guarantees statistical representativeness. A pre-test was conducted to ensure the validity of the questionnaire. Findings: It is shown that the total score of CTA and the six sub-dimensions are significantly positively correlated with SMU, but strongly negatively correlated with SMD. Based on the mediating effect testing, it is discovered that the degree of SMD can affect the promoting relations between the usage intensity of social media (UISM) and CTA. Clearly, SMU is a double-edged sword. While it narrows the digital gap in terms of accessibility, it widens the digital gap in terms of usage. Originality/value: The differences in SMU have a significant impact on the development of CTA of university students. This inspires us to consider the ability of "using social media in a balanced way" as an important evaluation and training direction when inquiring media literacy. As social media is becoming a critical channel in cultivating individual's thinking skills, it is highly suggested that the amount of time spent on reading fragmented information on the internet should be controlled. [ABSTRACT FROM AUTHOR]

Food system resilience has multiple dimensions. We draw on food system and resilience concepts and review resilience framings of different communities. We present four questions to frame food system resilience (Resilience of what? Resilience to what? Resilience from whose perspective? Resilience for how long?) and three approaches to enhancing resilience (robustness, recovery, and reorientation—the three "Rs"). We focus on enhancing resilience of food system outcomes and argue this will require food system actors adapting their activities, noting that activities do not change spontaneously but in response to a change in drivers: an opportunity or a threat. However, operationalizing resilience enhancement involves normative choices and will result in decisions having to be negotiated about trade-offs among food system outcomes for different stakeholders. New approaches to including different food system actors' perceptions and goals are needed to build food systems that are better positioned to address challenges of the future. [ABSTRACT FROM AUTHOR]

Urban agriculture can contribute to food security, food system resilience and sustainability at the city level. While studies have examined urban agricultural productivity, we lack systemic knowledge of how agricultural productivity of urban systems compares to conventional agriculture and how productivity varies for different urban spaces (e.g., allotments vs. rooftops vs. indoor farming) and growing systems (e.g., hydroponics vs. soil‐based agriculture). Here, we present a global meta‐analysis that seeks to quantify crop yields of urban agriculture for a broad range of crops and explore differences in yields for distinct urban spaces and growing systems. We found 200 studies reporting urban crop yields, from which 2,062 observations were extracted. Lettuces and chicories were the most studied urban grown crops. We observed high agronomic suitability of urban areas, with urban agricultural yields on par with or greater than global average conventional agricultural yields. "Cucumbers and gherkins" was the category of crops for which differences in yields between urban and conventional agriculture were the greatest (17 kg m−2 cycle−1 vs. 3.8 kg m−2 cycle−1). Some urban spaces and growing systems also had a significant effect on specific crop yields (e.g., tomato yields in hydroponic systems were significantly greater than tomato yields in soil‐based systems). This analysis provides a more robust, globally relevant evidence base on the productivity of urban agriculture that can be used in future research and practice relating to urban agriculture, especially in scaling‐up studies aiming to estimate the self‐sufficiency of cities and towns and their potential to meet local food demand. Plain Language Summary: By growing crops in cities and towns directly for urban consumers, we can make the food system more sustainable and resilient, and we can help to improve human health by increasing the accessibility to freshly grown foodstuffs. However, we lack information and evidence about what we can grow in urban areas, what quantity we can hope to produce, and which urban spaces could and should be used for urban food production. In this study, we aim to quantify the global crop yields of urban agriculture and see how they compare with those of conventional agriculture. We also investigate whether yields vary based on the urban spaces and growing systems where the crops are grown. We found that urban settings are productive places and can welcome a wide variety of crops (such as vegetables, legumes, cereals, soft fruit, orchard fruit, oil crops and fiber crops). Some spaces are more suited to specific crops than others, such as hydroponics for tomatoes, for instance. Findings from this paper allow us to draw a more accurate picture of the role urban agriculture could play in meeting global food demand alongside rural agriculture and contribute to increasing food security. Key Points: A meta‐analysis was conducted to quantify crop yields of urban agriculture and investigate how they compare with conventional agricultureUrban areas have high agronomic suitability, with urban agricultural yields on par with or greater than conventional agricultural yieldsYields differ significantly between certain urban spaces and growing systems where crops are grown, which shows varying crop suitability [ABSTRACT FROM AUTHOR]

This paper addresses the two-stage hybrid flow shop scheduling problem with a batch processor in the first stage and a discrete processor in the second stage. Incompatible job families and limited buffer size are considered. This hybrid flow shop configuration commonly appears in manufacturing operations and the batch processor is always the bottleneck which breaks the symmetry of processing time. Since making a real-time high-quality schedule is challenging, we focus on the automatic design of efficient heuristics for this two-stage problem based on the genetic programming method. We develop a hyper-heuristic approach to automate the tedious trial-and-error design process of heuristics. The goal is to generate efficient dispatching rules for identifying complete schedules to minimize the total completion time. A genetic programming with cooperative co-evolution approach is proposed to evolve the schedule policy automatically. Numerical results demonstrate that the proposed approach outperforms both the constructive heuristic and meta-heuristic algorithms, and is capable of producing high-quality schedules within seconds. [ABSTRACT FROM AUTHOR]

This paper addresses the complex job shop scheduling problem with the consideration of non-identical job sizes. By simultaneously considering practical constraints of sequence dependent setup times, incompatible job families and job dependent batch processing time, we formulate this problem into a simulation optimization problem based on the disjunctive graph representation. In order to find scheduling policies that minimise the expectation of mean weighted tardiness, we propose a genetic programming based hyper heuristic to generate efficient dispatching rules. And then, based on the nested partition framework together with the optimal computing budget allocation technique, a hybrid rule selection algorithm is proposed for searching machine group specified rule combinations. Numerical results show that the proposed algorithms outperform benchmark algorithms in both solution quality and robustness. [ABSTRACT FROM AUTHOR]

In this article the authors discuss the results of a study of the Chinese population in which many of those surveyed were concerned about urban air pollution or its health effects. The authors argue that despite the survey's results, ways to manage urban air quality through monitoring, information, and participatory approaches remains unresolved. Topics include the public perception about urban air quality and environmental information in China, the power of information, and social change.

A simple and powerful approach for assessing the recombination losses in dye sensitised solar cells (DSSCs) across the current voltage curve (j–V) as a function of TiO2electron concentration (n) is demonstrated. The total flux of electrons recombining with iodine species in the electrolyte and oxidised dye molecules can be thought of as a recombination current density, defined as jrec= jinj− jwhere jinjis the current of electrons injected from optically excited dye states and jis the current density collected at cell voltage (V). The electron concentration at any given operating conditions is determined by charge extraction. This allows comparison of factors influencing electron recombination rates at matched n. We show that jrecis typically 2–3 times higher under 1 sun equivalent illumination (jinj> 0) relative to dark (jinj= 0) conditions. This difference was increased by increasing light intensity, electrolyte iodine concentration and electrolyte solvent viscosity. The difference was reduced by increasing the electrolyte iodide concentration and increasing the temperature. These results allowed us to verify a numerical model of complete operational cells (Barnes et al., Phys. Chem. Chem. Phys., DOI: 10.1039/c0cp01554g) and to relate the differences in jrecto physical processes in the devices. The difference between jrecin the light and dark can be explained by two factors: (1) an increase in the concentration of electron acceptor species (I3−and/or I2) when current is flowing under illumination relative to dark conditions where the current is flowing in the opposite direction, and (2) a non-trivial contribution from electron recombination to oxidised dye molecules under light conditions. More generally, the technique helps to assign the observed relationship between the components, processing and performance of DSSCs to more fundamental physical processes. [ABSTRACT FROM AUTHOR]

Limited access to clean energy has long been an obstacle to livelihood improvement of populations mired in energy poverty. Cooking with traditional biomass contributes to high levels of indoor air pollution, thus imposing significant threats to public health. Due to the accessibility and affordability of clean fuels for rural residents, this study proposes that renewable solar energy be employed to supply power for induction cooking stoves (ICS) through solar home systems (SHS), and estimates both the costs and health benefits of upgrading to ICS and SHS in lower-middle-income countries (LMCs) in Southeast Asia. Disability-Adjusted Life Years and the value of a statistical life year were employed to estimate the health benefits of ICS-SHS. The results suggest that the health benefits brought by ICS-SHS alone can surpass the estimated minimum cost for an ICS-SHS in the six LMCs in Southeast Asia. This study provides a potential reference for getting other energy poverty regions involved with affordable, reliable, sustainable, and modern energy, as well as simultaneously tackling indoor air pollution caused by cooking. [ABSTRACT FROM AUTHOR]

Environmental incidents are among the most significant environmental challenges in China. Hundreds of environmental incidents occur every year, endangering human health and ecosystems. In this paper, we conducted an analytical study of environmental incidents from 2006 to 2015 in China. We first examined the spatiotemporal characteristics of the total 5213 incidents based on the statistical data collected from the China Statistical Yearbook on Environment . We then examined the characteristics of the sources of risk, causes of harm and resulting damage of environmental incidents based on first-hand data from 1369 cases collected by the Ministry of Environmental Protection (MEP) of China, which obtains detailed incident information. The results show that (1) there was a significant downward trend in the overall number of environmental incidents between 2006 and 2015, and developed eastern regions were high incidence areas; (2) hazardous chemicals were the main risk stressors; (3) production safety accidents and traffic accidents were the two major causes, and (4) most of these incidents resulted in polluted water and air. This paper is the first to provide a longitudinal analysis of the full scope of environmental incidents across the different regions of China, which has useful implications for policy-making and environmental management. [ABSTRACT FROM AUTHOR]

Recycling is an essential practice for the successful operation of zero waste cities. It is essential to understand the recyclable waste recycling potential (RWRP). This study quantifies the RWRP of different cities in China. Suzhou, Yangzhou, and Suqian represent high-, middle- and low-income cities, respectively. The RWRP statistics are based on systematic multiple longitudinal tracking field surveys conducted between 2016 and 2019. Obvious RWRP spatio-temporal disparities were observed between inter-city and intra-city. For instance, Suzhou showed a slight increase in high resource value paper; Yangzhou had a slight increase in low resource value paper; and Suqian had a huge increase in no resource value paper and plastic. Additionally, more recyclable organics were generated in the old districts of Suzhou, and they were also predominant in the new districts of Yangzhou. No significant difference was observed in recyclable organics and recyclable material in Suqian. However, recyclable organics is a constant, while recyclable material fluctuates in the case cities. Household consumption structure has a major impact on RWRP. Other factors, such as economic development, urban resident population, consumption preferences, local customs and culture, as well as residential lifestyles also affect RWRP. This study proposes three policies: 1) to establish flexible and carefully planned recycling strategies, 2) to develop the distribution market of composting products, and 3) to incorporate economic and demographic initiatives to develop a workable recycling policy that can lead to zero waste implementation in the future. The zero waste concept was further assessed by the authors' review of 69 cities worldwide based on previous research. We compared past results with the three featured cities in this study and 35 other Chinese cities, thereby presenting a world view of zero waste potential. It is anticipated that representative cities' RWRP quantification and policy implementations can be a model for municipal solid waste management and recycling policies in other Chinese cities, which will help them transition to zero waste cities and probably provide a model for cities worldwide. [Display omitted] • A longitudinal survey was performed in 3 cities with different income levels. • Recycling potential and recyclable waste stream generation were quantitated. • Spatiotemporal disparity effects on recycling potential are discussed. • Practical recycling policies are suggested with zero waste goals in the future. [ABSTRACT FROM AUTHOR]

In China, nitrogen oxide (NOx) emissions have been declining in recent years, whereas NOx generation continues to increase. This has prompted a growing focus of policy design to inspect the driving mechanisms of NOx generation. In this study, a decomposition model of NOx generation in China from 1995 to 2014 was built using the Logarithmic Mean Divisia Index (LMDI) method. According to the decomposition results, technological effects (e.g., energy intensity and the sector generation factor) inhibited NOx generation in China, while gross domestic product (GDP) per capita was found to have the most positive effect on increasing NOx generation, accounting for 151.00% of the total change and showing an increasing trend in recent years. The sector structure of energy consumption always increased NOx generation, which contradicts the results of previous studies. All population effects considered in this study contributed to the growth in NOx generation. The population scale effect was increasingly impactful on the growth of NOx generation; the population spatial structure was active but less impactful. In general, technological impact cannot offset the increases caused by economic, structural, and population effects. Considering NOx reduction policy in China, more attention should be given to emission reduction policies, energy consumption, and socio-economic effects; together, these approaches will improve initiatives to reduce NOx. [ABSTRACT FROM AUTHOR]

China has modified its pollution control policy system with such price tools as the pollution charge (PC) policy and the payment for initial emission allowance (PIEA) policy. The aim of PC policy is to compensate for the environment damage caused by pollutants, while PIEA is in charge of the initial emission allowance (IEA) within the emission trading system (ETS). However, since the implementation of PIEA, it has been criticized as redundant because of the similar pricing scheme with the PC. In addition, the existing PIEA pricing approaches have ignored interactions with other policies, such as PC and total emission control (TEC) policies. In this research, we established an optimal control-based model with chemical oxygen demand (COD) and ammoniacal nitrogen (NH 3 -N), two independent pollutants variables, to simulate the water pollutants' PIEA price. Simulation results indicated that emission quantity and optimal social benefit in the PC–PIEA combination scenario was equal to the situation in the PIEA scenario. Under this design, PC compensated for the emission damage, and PIEA paid for the scarcity rent, while PIEA does not duplicate the PC policy. In addition, the PIEA policy has a complex effect on pollutant emission. Because PIEA policy increases the enterprises' discharging cost, most regions' COD emissions are less than the baseline, excepting Beijing, Shanghai, Jiangsu, Zhejiang, Fujian, Shandong, and Guangdong, in which emission quantities are greater than the baseline. The NH 3 -N emission shows an opposite trend. The simulation result is that excluding Inner Mongolia, Hubei, Hunan, Tibet, Gansu, Qinghai, Ningxia, and Xinjiang, the NH 3 -N emissions in the rest of regions are increased. TEC policy has a significant effect on pollutant emissions and the PIEA price. The COD emission quantity with TEC is lower than that without the TEC policy, therefore, the TEC policy will be effective for pollutant emission control. The pollutant beyond the restricted target will be charged a payment for IEA at a higher price than without the TEC policy. [ABSTRACT FROM AUTHOR]

The increasing vehicle numbers in China have raised issues on effective mitigation of the vehicular NO x emissions recently. Notably, temporally growing and spatial agglomeration of high vehicular NO x emissions make an essential challenge to the mitigation strategy-makers. However, so far, there have been few studies to give insight into the socioeconomic drivers like the spatial imbalance of socioeconomic development, vehicle structure and road infrastructure to help governors. To fill the above gap, this study explores drivers of temporal change and spatial differences by building a temporal-spatial decomposition model and accounting for national and regional NO x emissions from vehicles in China from 2005 to 2015. Results show that, of all the driving forces in this study, only road vehicle carrying capacity (ΔN VI) acts as a primary driving force for both temporal growing and spatial agglomeration of vehicular NO x emissions in China. Regional vehicle emission intensity (ΔN NI) and road economic growth (ΔN EI) only mainly contributed to spatial agglomeration. While economic development (ΔN G) played a crucial role in the temporal growing of vehicular NO x emissions in China. These findings indicate that the future mitigation policy should fully cover the comprehensive socioeconomic factors, which would be useful for China and other developing countries when aiming to improve the performance of their current vehicle emissions policy system. Image 1 • China's NO x emissions from provincial vehicles were estimated during 2005–2015. • A new temporal-spatial decomposition model was built to identify emission drivers. • Road vehicle carrying capacity drives both temporal change and spatial difference. • Regional emission intensity and road economic growth affect spatial difference. • Economic development played a crucial role in the temporal change. [ABSTRACT FROM AUTHOR]

In the West, limited government capacity to solve environmental problems has triggered the rise of a variety of "nonstate actors" to supplement government efforts or provide alternative mechanisms for addressing environmental issues. How does this development - along with our efforts to understand it - map onto environmental governance processes in China? China's efforts to address environmental issues reflect institutionalized governance processes that differ from parallel western processes in ways that have major consequences for domestic environmental governance practices and the governance of China "going abroad." China's governance processes blur the distinction between the state and other actors; the "shadow of the state" is a major factor in all efforts to address environmental issues. The space occupied by nonstate actors in western systems is occupied by shiye danwei ("public service units"), she hui tuanti ("social associations") and e-platforms, all of which have close links to the state. Meanwhile, international NGOs and multinational corporations are also significant players in China. As a result, the mechanisms of influence that produce effects in China differ in important ways from mechanisms familiar from the western experience. This conclusion has far-reaching implications for those seeking to address global environmental concerns, given the importance of China's growing economy and burgeoning network of trade relationships., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Photocurrents generated by thick, strongly absorbing, dye-sensitized cells were reduced when the electrolyte iodine concentration was increased. Electron diffusion lengths measured using common transient techniques (L(n)) were at least two times higher than diffusion lengths measured at steady state (L(IPCE)). Charge collection efficiency calculated using L(n) seriously overpredicted photocurrent, while L(IPCE) correctly predicted photocurrent. This has implications for optimizing cell design.