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Reducing emissions from light duty vehicles is critical to meet current and future air quality targets. With more focus on real world emissions from light-duty vehicles, the interactions between engine and exhaust gas aftertreatment are critical. For modern engines, most emissions are generated during the warm-up phase following a cold start. For Diesel engines this is exaggerated due to colder exhaust temperatures and larger aftertreatment systems. The De-NOx aftertreatment can be particularly problematic. Engine manufacturers are required to take measures to address these temperature issues which often result in higher fuel consumption (retarding combustion, increasing engine load or reducing the Diesel air-fuel ratio). In this paper we consider an inner-insulated turbocharger as an alternative, passive technology which aims to reduce the exhaust heat losses between the engine and the aftertreatment. Firstly, the concept and design of the inner-insulated turbocharger is presented. A transient 3D CFD/FEM (Computation Fluid Dynamics/Finite Element Modelling) simulation is conducted and predicts that external heat losses will be reduced by 70% compared to a standard turbocharger, i.e. non-insulated turbocharger. A 1D modelling methodology is then presented for capturing the behaviour of the inner-insulated turbocharger. This is important as conventional models based on isentropic efficiency maps cannot accurately predict turbine outlet temperature. The alternative model is essential to demonstrate benefits in system-level simulations. Experimental results are presented from a transient air-path testing facility to validate the 1D model and demonstrate the characteristics of the inner-insulated turbocharger. Finally, the validated 1D model is used within a powertrain optimization simulation to demonstrate an improvement in fuel consumption for iso-NOx emissions over a low load city cycle of up to 3%. The work was conducted under the THOMSON project which has received funding from the European Union's Horizon 2020 Program for research, technological development and demonstration under Agreement no. 724037. The project aims to increase the market penetration of 48V hybrid vehicles.

Impacts of man-made acoustic noise on the marine environment are associated to the frequency and timing of any activity as well as the distribution and abundance of marine life. Offshore commercial operations, shipping activities, energy exploration and pile driving add noise to the already established ambient noise levels. Attention has been raised by the years to the topic of underwater noise and its effects on marine life, but the effects of underwater noise are not yet fully understood. As the adoption of the European Marine Directive (MSFD 2008/56/EC - Descriptor 11) has given great impulse to the research in this field, governments, companies and institutes are working to specify the background ambient noise levels. Those studies have formed the guidelines and have set the protocols for performing safer offshore operations, which are adopted by the major energy companies. Hellenic Petroleum S.A. has undertaken a Marine Seismic Survey in West Patraikos Gulf waters in Greece between January and February 2016, which was coupled with an intensive sound noise monitoring program. Acoustic data were collected around Marine Protected Areas of the Inner Ionian Archipelago during three monitoring phases: 1) the pre-start, 2) the concurrent and 3) the post-completion ones. Sound pressure levels (SPLs) were collected using drifting hydrophones deployed on a frequent schedule, spanning 1.5 months, collecting more than 130 hours of data. The ambient noise data gave insight into the footprints of the anthropogenic and biogenic factors on the soundscape of the Inner Ionian Archipelago. Most importantly, the recorded SPLs of the impulsive seismic and the continuous shipping noises were studied against the bearing and distance to the corresponding sound sources.

Strategies implemented worldwide to contain COVID-19 outbreaks varied in severity across different countries, and established a new normal for work and school life (i.e., from home) for many people, reducing opportunities for physical activity. Positive relationships of physical activity with both mental and physical health are well recognised, and therefore the aim was to ascer-tain how New Zealand's lockdown restrictions impacted physical activity, mental health and well-being. Participants (n = 4007; mean ± SD: age 46.5 ± 14.7 years, 72% female, 80.7% New Zealand European) completed (10–26 April 2020) an online amalgamated survey (Qualtrics): International Physical Activity Questionnaire: Short Form; Depression, Anxiety and Stress Scale-9; World Health Organisation-Five Well-Being Index; Stages of Change Scale. Positive dose–response relationships between physical activity levels and wellbeing scores were demonstrated for estimates that were unadjusted (moderate activity OR 3.79, CI 2.88–4.92; high activity OR 8.04, CI 6.07–10.7) and adjusted (confounding variables: age, gender, socioeconomic status, time sitting and co-morbidities) (moderate activity 1.57, CI 1.11–2.52; high activity 2.85, CI 1.97–4.14). The study results support pre-vious research demonstrating beneficial effects of regular physical activity on mental health and wellbeing. Governments may use these results to promote meeting physical activity guidelines in order to protect mental health and wellbeing during the ongoing COVID-19 restrictions and future pandemics.

Mental health and emotional responses to the effects of COVID-19 lockdown in sub-Saharan Africa (SSA) are of serious public health concern and may negatively affect the mental health status of people. Hence, this study assessed the prevalence of mental health symptoms as well as emotional reactions among sub-Saharan Africans (SSAs) and associated factors among SSAs during the COVID19 lockdown period. This was a web-based cross-sectional study on mental health and emotional features from 2005 respondents in seven SSA countries. This study was conducted between 17 April and 17 May 2020 corresponding to the lockdown period in most SSA countries. Respondents aged 18 years and above and the self-reported symptoms were feeling anxious, being worried, angry, bored and frustrated. These were the main outcomes and were treated as dichotomous variables. Univariate and multivariate logistic regression analyses were used to identify the factors associated with these symptoms. We found that over half (52.2%) of the participants reported any of the mental health symptoms and the prevalence of feeling bored was 70.5% followed by feeling anxious (59.1%), being worried (57.5%), frustrated (51.5%) and angry (22.3%) during the COVID-19 pandemic. Multivariate analysis revealed that males, those aged >28 years, those who lived in Central and Southern Africa, those who were not married, the unemployed, those living with more than six persons in a household, had higher odds of mental health and emotional symptoms. Similarly, people who perceived low risk of contracting the infection, and those who thought the pandemic would not continue after the lockdown had higher odds of mental health and emotional symptoms. Health care workers had lower odds for feeling angry than non-healthcare workers. During the COVID-19 lockdown periods in SSA, about one in two participants reported mental health and emotional symptoms. Public health measures can be effectively used to identify target groups for prevention and treatment of mental health and emotional symptoms. Such interventions should be an integral component of SSA governments' response and recovery strategies of any future pandemic.

Interest is growing in carbon dioxide enhanced oil recovery (CO 2 -EOR) as an additional economic incentive for CO 2 injection and demonstration of storage feasibility. However, given increasing societal concern over fossil fuel energy, could CO 2 -EOR unintentionally hinder conventional CCS by reducing support from neutral or cautiously supportive voices? This paper assesses how stakeholders and citizens respond to four scenarios for CCS with CO 2 -EOR in the North Sea, and draws societal implications for deployment in other mature basins. Based on focus group data from Aberdeen, Edinburgh and London, we argue that scenarios emphasising maximising oil recovery may be met with scepticism or even opposition, and that there is an expectation for national governments to lead and ensure CO 2 -EOR (and CCS more generally) are undertaken in the public interest. Nonetheless, our data also suggest a certain degree of pragmatism as to the embeddedness of fossil fuels in society, and thus that there may be qualified support for CCS with CO 2 -EOR as making best use of existing fields whilst decarbonising the power and industrial sectors. However, for this support to emerge there is an imperative for coherent and credible policy that positions CO 2 -EOR firmly within a managed transition towards a low-carbon economy.

BACKGROUND: Microbial oils, often termed single cell oils (SCOs), offer an alternative to terrestrial oil crops across the energy, food, and chemical industries. In addition to oils, a range of secondary metabolites can be produced from the heterotrophic organisms as part of a bio-refinery system. Techno-economic analysis (TEA) is an important tool for evaluating economic viability, and while TEA is subject to high uncertainties where production is still at the laboratory scale, the tool can play a significant role in directing further research to evaluate suitability of scale-up. RESULTS: SCO production from the oleaginous yeast Metschnikowia pulcherrima using sucrose, wheat straw and distillery waste feedstocks was evaluated at two production scales. At a scale of 100 tonnes a-1 oil production a minimum estimated selling price (MESP) of €14k per tonne was determined for sucrose. This reduced to €4-8k per tonne on scaling to 10,000 tonne a-1, with sucrose and wheat straw yielding the lowest MESP. CONCLUSIONS: Feedstock price and lipid yield had the greatest impact on overall economic return, though the valorisation of co-products also had a large effect, and further play between feedstock and system productivity strategies could bring the price down to be competitive with terrestrial oils in the future. The novel approach demonstrated here for the first time integrates uncertainty into economic analysis whilst facilitating decision-support at an early technology development stage. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 665992

Military activities have left a legacy of depleted uranium (DU) penetrator waste in the near-surface terrestrial environment. To understand the fate of this DU alloy, the mechanisms and controlling factors of corrosion need to be determined. In this study, field-moist and waterlogged microcosms were used to investigate the effect of redox conditions and soil water content on the corrosion and fate of DU in subsurface soil, and the impact of corroding DU on the soil microbial population. The mechanism of corrosion and the corrosion products formed were highly dependent on the water status of the soil. Under field-moist conditions, DU corroded at a rate of 0.49 ± 0.06 g cm -2 y-1 and the main U input to surrounding soil was large metaschoepite [(UO2)8O2(OH) 12·(H2O)10] particles. However, under waterlogged conditions the rate of corrosion was significantly slower at 0.01-0.02 g cm-2 y-1 and occurred with the release of dissolved species to the surrounding environment. Corrosion ceases under reducing conditions, thus redox conditions are important in determining the persistence of penetrators in the environment. Corroding DU alters the redox conditions in the surrounding environment and both mechanisms of corrosion impact the microbial community. © 2009 American Chemical Society.

The United Nation's 17 Sustainable Development Goals (SDGs) offer an extensive framework for coordinating and shaping government policies, and for engaging the public with sustainability. Public understanding of the SDGs and sustainability can influence this engagement, as people are more likely to accept and share information consistent with their own understanding. We identify public understandings of SDGs through mental maps of how people relate the SDGs to environmental, social and economic sustainability. Using responses from 12 developed/developing countries (n = 2,134), we identified four mental maps that varied mainly on two dimensions, which diverged from some expert models. Some people's mental maps identified tension between achieving environmental versus social sustainability, whereas for others the tension was between economic sustainability and the other two sustainability elements. Some people related different SDGs to each element of sustainability, whereas others saw all SDGs as targeting the same sustainability element(s). These findings highlight opportunities and challenges to engage the public with sustainability more effectively, especially with wide-ranging initiatives such as a Green New Deal. We observed cultural differences but we also identified a dominant mental map across countries that could serve as a default model for communicating sustainability internationally.

While there is a substantial body of research focused on the links between North-South trade and sustainable development, research on South-South trade and sustainable development is still in its infancy. Given current understandings of the drivers of sustainable development, one might expect increasing trade in agricultural commodities within the global South to have a negative impact on sustainable development opportunities. In this sense, the Ceylon tea industry presents a puzzle. Despite exporting most of its tea to Southern markets, it has been among the top performers in terms of economic, social, and environmental practices. As such, the case raises a number of questions around shifting trade patterns and their implications for sustainability outcomes. I address these questions through four propositions – three mechanisms and one condition – through which South-South trade can expand the opportunities for sustainable development. While the exact nature of sustainable development outcomes will ultimately be decided through domestic political struggles, shifts toward more equal trade can make sustainable production more likely. Overall, the analysis draws attention to nuanced ways in which end markets shape their respective supply chains and how these dynamics impact the potential for actors operating at the bottom of supply chains to shape sustainability outcomes.

The discursive and representational aspects of the multiple political, economic and cultural challenges associated with low carbon urban transitions remain insufficiently explored in the academic literature. This is particularly true in the post-communist states of eastern and central Europe, which have been undergoing an additional transition of their own-from a centrally planned to a market-based economy. This paper, therefore, explores the manner in which climate change and sustainability narratives have been implicated in the development of 'satellite settlements'-a specific form of sprawl present in the Czech Republic. Much of the paper is focused on investigating the discursive framings of such areas by relevant state policies and the national media in this country. Several key themes and discursive shifts in the representation of satellite settlements have been detected. Such changes may be connected to wider interactions among the dynamics of post-communist and low-carbon urban transition. © 2013 Urban Studies Journal Limited.

There now exists a significant body of theoretically informed empirical research into 'neoliberal environments'. It comprises numerous studies which together explore the connections between neoliberal principles and policies, on the one side, and the biophysical world on the other. However, making sense of them is by no means straightforward, despite their common focus on neoliberal environments. It is currently left to readers of these studies to synthesise them into a wider, joined-up account of neoliberal environments. This and two companion articles aim for precisely this sort of broad and coherent understanding. The contribution of this second instalment is to present an overarching political economic theory of 'neoliberal environments'. By synthesising concepts from the work of Karl Marx, Karl Polanyi and James O'Connor, this article presents a framework for thinking about how neoliberal policies relate to the biophysical world. © 2010 The Author. Geography Compass © 2010 Blackwell Publishing Ltd.

There now exists a significant body of theoretically informed empirical research into 'neoliberal environments'. It comprises numerous studies which together explore the connections between neoliberal principles and policies, on the one side and the biophysical world on the other. These studies are, for the most part, political economic in character and authored by so-called 'critical' geographers. However, making sense of them is by no means straightforward, despite their common focus on neoliberal environments. This is because neoliberalism and the biophysical world are complex phenomena, making an holistic and comprehensive understanding of them very challenging to achieve. Accordingly, separate studies of their interconnections have focused on one or other aspect of the complexity in a particular time and context. It is currently left to readers of these studies to synthesise them into a wider, joined-up account of neoliberal environments. This and two companion articles aim for precisely this sort of broad and coherent understanding. This article begins with a discussion of neoliberalism and explains why it necessarily has environmental aspects to it. The second companion article presents a theory of 'neoliberal environments', while the third connects that theory to the empirical findings of studies published to-date. This final article also departs from the otherwise constructive tone of its companions. Together, the three articles offer readers both an overarching understanding of 'neoliberal environments' and some tools to question the way these environments are currently understood by many geographers. © 2010 The Author. Geography Compass © 2010 Blackwell Publishing Ltd.

This paper explores the use of LCA as a tool for process environmental management, thereby moving the focus from product to process oriented analysis. The emphasis is on Improvement Assessment in which the 'hot spots' in the system are targeted for maximum environmental improvements. In this context, it is useful to use multiobjective optimisation which renders valuation unnecessary. The approach is illustrated by the case study of the system processing boron ores to make five different products. The results of Inventory Analysis and Impact Assessment are presented and discussed. In Improvement Assessment, a number of improvement options are identified and evaluated, using system optimisation. It is shown that the site environmental performance can be improved over current operation by an average of 20% over the whole life cycle. Thus the study demonstrates that the optimisation approach to environmental process management may assist in identifying optimal ways to operate a process or plant from 'cradle to grave'. This may help the process industries not only to comply with legislation but also provide a framework for taking a more proactive approach to environmental management leading to more sustainable industrial operations and practices.

Heat waves give rise to order of magnitude higher mortality rates than other weather-related natural disasters. Unfortunately both the severity and amplitude of heat waves are predicted to increase worldwide as a consequence of climate change. Hence, meteorological services have a growing need to identify such periods in order to set alerts, whilst researchers and industry need representative future heat waves to study risk. This paper introduces a new location-specific mortality risk focused definition of heat waves and a new mathematical framework for the creation of time series that represents them. It focuses on identifying periods when temperatures are high during the day and night, as this coincidence is strongly linked to mortality. The approach is tested using observed data from Brazil and the UK. Comparisons with previous methods demonstrate that this new approach represents a major advance that can be adopted worldwide by governments, researchers and industry.

Across mineral-rich sub-Saharan Africa, it has become increasingly common for mining companies to support development schemes in host communities where resource extraction takes place. The negotiation of so-called 'community development agreements' (CDAs), provides an opportunity to address the social and environmental impacts of mining, while at the same time serving as a platform through which company-community relations can be mediated. Unlike discretionary corporate social responsibility programmes, in many countries, CDAs are embedded in law, invoking parties' mutual commitments and responsibilities. Such initiatives have been heralded as 'game–changers', promising equitable redistribution of wealth, structured community development and stable investment climates for extractives companies. However, factors that concern the process of their negotiation, coupled with structural weaknesses, can affect their implementation, transforming them into spaces of contestation which can threaten their potential. Drawing upon fieldwork carried out in Sierra Leone between 2013-2018, this paper critically explores the contested nature of CDAs. Focusing on two different case studies in the south and east of the country, it argues that such agreements will only contribute to genuine development in host communities if the longstanding issues that have stalled the pre-existing forms and instruments of community development are systematically addressed.