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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]

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]

In recent decades, large-scale deployment of photovoltaic (PV) power leads to management challenges for recycling PV module waste in China. With the growth of waste PV volumes, it is necessary to figure out the spatio-temporal distribution of PV waste at the provincial level. Based on China's carbon neutrality goal by 2060, six development pathways of PV installed capacity are proposed to identify in-use stocks of PV capacity. In particular, we develop the retired flow estimation model for PV modules that is constructed by three PV module degradation scenarios. The results show that a relatively large scale of PV waste will be started to emerge in China by 2030 and the cumulative waste is expected to reach 1100 ∼ 1450 GW by 2060. Our findings also indicate an unequal distribution of PV waste across regions and the highest PV waste volumes by 2060 is the East China region at 31.4%, with Shandong (8.99%) and Hebei(8.65%) ranking as the top provinces. This prospective research will help the PV industry plan the location and capacity of recovery facilities at an appropriate time to advance toward a more resource efficient and circular economy. [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 studies the scheduling problem of jobs with release times, non-identical sizes, and incompatible job families on unrelated parallel batch machines. The capacities of batch machines and the processing times of each job on the batch machines are different. The processing time of one batch is equal to the longest processing time of jobs in this batch. Different types of jobs are not allowed to be assigned into the same batch, which is known as incompatible job families. Mixed integer linear programming and constraint programming (CP) models are proposed. A new batch-based local search method is designed and an iterated greedy (IG) algorithm is developed to avoid unreasonable exchanging of jobs during the local search. Numerical results show that the CP method can obtain high quality solutions in the small-scale instances. For the large-scale instances, the IG algorithm with the new local search method has a competitive performance. [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]

Purpose The purpose of this paper is to investigate how local supply chains prepare for and respond to the threats and opportunities presented by constitutional change, thereby building resilience.Design/methodology/approach Multiple case study analysis of 14 firms in the food sector is presented in the context of the UK's impending exit from the European Union (Brexit). Organisations studied include farmers, processors, retailers and non-government organisations (NGOs). Data from interviews and roundtable discussions has been interpreted using the dynamic capabilities perspective, covering the sensing, seizing, and transforming stages.Findings The data highlights the importance of both vertical and horizontal collaboration between supply chain actors as they seek to anticipate the impact of the disruption and influence the future shape of the constitution. There is also evidence to suggest firms in possession of dynamic capabilities can innovate to build resilience and enhance their competitive position. Characteristics of the disruption posed by constitutional change are identified and contrast with those of many other threats more typically described in the literature. As a result, the process of building resilience is different.Research limitations/implications The study could be extended to include post-Brexit interviews to further understand the seizing and transforming stages whilst the impact of Brexit on actors that remain within the EU could also be considered.Practical implications Practitioners need to work together to influence the future shape of the constitution; and they need to reconfigure their operations and supply chains where necessary to become more resilient to the threat posed by Brexit, such as by reducing their reliance on EU funding streams and trade. The study also has policy implications.Originality/value The first study of supply chain resilience to constitutional change and a rare empirical study of resilience across multiple supply chain tiers. [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]