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Abstract The building industry has been developing measures for reducing operational emissions in the fight against climate change. Some of these well-intentioned measures may result in higher embodied emissions, potentially more than offsetting reductions achieved during operation. This research evaluates the effectiveness of different levels of application of five passive energy efficiency measures to reduce life cycle greenhouse gas (GHG) emissions in high-rise residential buildings in Toronto, Canada, while considering projected future climate and GHG intensity of energy sources. Through combining and automating life cycle assessment and energy simulation on a visual programing interface, the study evaluates 16,128 envelope variants, examining 56 wall, 12 roof, 6 window assemblies and 4 window-to-wall ratios (WWRs). Decreasing the WWR is found to be the most effective measure to reduce total envelope related GHG emissions (by about 28%). Increasing wall and roof insulation with GHG intensive materials (e.g., extruded polystyrene [XPS]), and increasing spandrel wall insulation potentially augment total emissions, depending on the scenario. Higher trade-offs between embodied and operational emissions are found when highly efficient electric HVAC systems are implemented (e.g., heat pumps). Results demonstrate it is imperative to assess both embodied and operational emissions during the design process of building envelopes to effectively reduce GHG emissions.

The life cycle Greenhouse Gas (GHG) emissions associated with the production and use of transportation fuels from conventional and unconventional fossil fuel sources in Canada and the USA are investigated. The studied pathways include reformulated gasoline and low sulphur diesel produced from oil sands, oil shale, coal and natural gas, as well as reference pathways from conventional crude oil. A comparison of Life Cycle Assessments (LCAs) completed for these fuels indicates considerable uncertainty in these emissions, illustrating the need for further LCAs with particular attention to completeness and transparency. Based on the considered studies, only one unconventional pathway has better GHG emissions performance than the conventional pathways: Fischer-Tropsch diesel from natural gas. However, the limitations of the data used here and other factors that may restrict a switch to natural gas must be considered. Furthermore, there are considerable opportunities to reduce emissions from the unconventional pathways.

Sustainability is now a major concern in society, but there is little understanding of how it is perceived by software engineering professionals and how sustainability design can become an embedded part of software engineering process. This paper presents the results of a qualitative study exploring requirements engineering practitioners’ perceptions and attitudes towards sustainability. It identifies obstacles and mitigation strategies regarding the application of sustainability design principles in daily work life. The results of this study reveal several factors that can prevent sustainability design from becoming a first class citizen in software engineering: software practitioners tend to have a narrow understanding of the concept of sustainability; organizations show limited awareness of its potential opportunities and benefits; and the norms in the discipline are not conducive to sustainable outcomes. These findings suggest the need for focused efforts in sustainability education, but also a need to rethink professional norms and practices.

Background: Sodium oxybate (SMO) has been shown to be effective in the maintenance of abstinence (MoA) in alcohol-dependent patients in a series of small randomized controlled trials (RCTs). These results needed to be confirmed by a large trial investigating the treatment effect and its sustainability after medication discontinuation. Aims: To confirm the SMO effect on (sustained) MoA in detoxified alcohol-dependent patients. Methods: Large double-blind, randomized, placebo-controlled trial in detoxified adult alcohol-dependent outpatients (80% men) from 11 sites in four European countries. Patients were randomized to 6 months SMO (3.3–3.9 g/day) or placebo followed by a 6-month medication-free period. Primary outcome was the cumulative abstinence duration (CAD) during the 6-month treatment period defined as the number of days with no alcohol use. Secondary outcomes included CAD during the 12-month study period. Results: Of the 314 alcohol-dependent patients randomized, 154 received SMO and 160 received placebo. Based on the pre-specified fixed-effect two-way analysis of variance including the treatment-by-site interaction, SMO showed efficacy in CAD during the 6-month treatment period: mean difference +43.1 days, 95% confidence interval (17.6–68.5; p = 0.001). Since significant heterogeneity of effect across sites and unequal sample sizes among sites ( n = 3–66) were identified, a site-level random meta-analysis was performed with results supporting the pre-specified analysis: mean difference +32.4 days, p = 0.014. The SMO effect was sustained during the medication-free follow-up period. SMO was well-tolerated. Conclusions: Results of this large RCT in alcohol-dependent patients demonstrated a significant and clinically relevant sustained effect of SMO on CAD. Trial registration: ClinicalTrials.gov Identifier: NCT04648423

To address the challenge of achieving social learning in support of transformative change to sustainability, this paper develops an analytical framework that applies a social practice theory (SPT) lens to illuminate the constituent elements and dynamics of social learning in the context of transdisciplinary coproduction for sustainability transitions. Adopting an SPT approach affords a means of interpreting concrete practices at the local scale and exploring the potential for scaling them up. This framework is then applied to a real-world case at the urban neighbourhood scale in order to illustrate how social learning unfolded in a grassroots transdisciplinary coproduction process focused on climate action. We find that a social practice perspective illuminates the material and nonmaterial dimensions of the relationship between social learning and transdisciplinary coproduction. In decoupling these properties from individual human agency, the SPT perspective affords a means of tracing their emergence among social actors, generating a deeper understanding of how social learning arises and effects change, and sustainability can be reinforced.

Two different sized hydropower projects in China, one with a capacity of 44 MW and the other of 3,600 MW, were examined through life-cycle assessment (LCA) from the perspective of both sustainability and environmental impact and the influence of project scale. Using the economic input-output based LCA approach, energy use and greenhouse gas (GHG) emissions were quantified. The resulting energy payback ratios were found to be 7 and 48, whereas the normalized GHG emissions were 44 and 6 g CO 2 equivalent per kW h of electricity production, both in favor of the larger project. Compared with published data on other renewable and nonrenewable options, temperate hydropower, particularly large hydropower, is indicated as an efficient electrical source with relatively low GHG emissions.

A refined version of the Fundamenksi-Moulton 'free-streaming' model (FSM) for the dynamics of divertor density, particle flux, and heat flux during edge localized modes (ELMs) is presented. This model depends only on inter-ELM pedestal and divertor conditions and, crucially, incorporates particle recycling: a FSM with recycling model, FSRM. The effective particle recycling coefficient, Reff, is the only empirical fitting parameter in the FSRM. The predictions of the FSRM are systematically tested against a DIII-D database of ELM ion and energy fluence measurements and are shown to be consistent with the model across a wide range of pedestal and divertor conditions using a constant value of 0.96 for Reff . Predictions for W sputtering during ELMs are developed based on the FSRM. It is concluded that energetic free-streaming D+ ions and C6+ impurities are the dominant contributors to the intra-ELM gross erosion of W in the DIII-D divertor, i.e., recycling ions and impurities have relatively little impact on the total W sputtering rate. These calculations are also shown to be consistent with spectroscopic measurements of W gross erosion for three different pedestal conditions after incorporating the strong electron density dependence of the WI 400.8 nm ionizations/photon (S/XB) coefficient. Keywords: Tungsten sputtering, Tungsten Erosion, WI spectroscopy, Edge Localized Modes, Recycling

Over the last thirty years, sustainability has become a growing concern in the fashion industry. While there is agreement among a growing range of actors regarding the need to engage with the social and environmental challenges created by the fashion industry, there is less consent regarding what sustainability entails. Although “sustainability” may be intuitively understood, it has different meanings, depending on how it is applied, and who it is applied by. Without a clear-cut definition, sustainability becomes subjective. In this context, there is a need for research at the intersection of brand-sustainability initiatives and their communication to consumers, who play a vital role in this transition. Drawing on a case study of the Swedish fashion industry, we explore how evolving industrial business models and emerging best practices are informed by a robust understanding of sustainability. We evaluate how brands communicate sustainability to consumers across three key sites: brand websites (including corporate social responsibility reports), social media platforms, and in-store campaigns. We found that not only do brands use a range of practices to define sustainability differently, but furthermore, these definitions vary depending on the context. Considering the industry’s ongoing history with greenwashing, it is vital to address and confront this issue head on. We argue that there is a need to determine what constitutes sustainability in the fashion industry and, in turn, hold businesses to that standard. As COVID-19 has only magnified and intensified these challenges, the article explores the implications of a more robust approach for both theory and practice.