In this Communication, the discussion of work by the Kraus research group was not precisely expressed and should be corrected to the following: Kraus and Wei [3d] reported that 7 and its diastereomer, which were claimed to be isolated as by-products in their elegant synthesis of racemic hyperolactone C, could not be converted into a lactone using heat, acid (PTSA), or base (tBuOK, NaH, or KH) catalysis. However, careful analysis and comparison of the NMR data of 13 (1:1 mixture of diastereomers) with both the by-products reported by Kraus and Wei indicated that they were identical (see the Supporting Information). Moreover, the value of d = 155.9 ppm in the 13 C NMR data listed for compound 13 in the Supporting Information should be removed. The authors are grateful to Prof. David Hodgson of Oxford University for pointing this out.

This paper brings together several contemporary topics in energy systems aiming to provide a literature review based reflection on how several interrelated energy systems can contribute together to a more sustainable world. Some directions are discussed, such as the improvement of the energy efficiency and environmental performance of the systems, the development of new technologies, the increase of the use of renewable energy sources, the promotion of holistic and multidisciplinary studies, and the implementation of new management rules and "eco-friendly and sustainable" oriented policies at different scales. The interrelations of the diverse energy systems are also discussed in order to address their main social-economic-environmental impacts. The subjects covered include the assessment of the electricity market and its main players (demand, supply, distribution), the evaluation of some urban systems (buildings, transportation, commuting), the analysis of the implementation of renewable energy cooperatives, the discussion of the diffusion of the electric vehicle and the importance of new bioenergy systems. This paper also presents relevant research carried out in the framework of both the Energy for Sustainability Initiative of the University of Coimbra and the Sustainable Energy Systems focus area of the MIT-Portugal Program. To conclude, several research topics that should be addressed in the near future are proposed.

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Low voltage electrowetting can be achieved by modifying silicone oil impregnated PTFE membrane with PFOTS.

Purpose: Screening Social Life Cycle Assessment (S-LCA) can be applied to identify the social hotspots associated with a production activity or supply chain. The objective of this paper is to explore how the quality of the results of a screening S-LCA can be improved, illustrated by a case study of sugarcane production in Brazil. Methods: Cradle-to-gate production of sugarcane in Brazil has been modelled using input-output analysis. The associated social impacts have been modelled using the framework of the Social Hotspots Database (SHDB), which is one of the first databases providing information on social risks along supply chains. The results from the SHDB were complemented with results from a systematic analysis of relevant literature. Content analysis was applied to 38 publications in English relevant to the social impacts of sugarcane production in Brazil, including peer-reviewed articles, "grey literature", Non-Governmental Organization reports and conference presentations. Qualitative data analysis software NVivo 8 was used to facilitate the analysis of the publications. A deductive category system was established based on the subcategories recommended in the UNEP/SETAC Social Life Cycle Assessment guidelines. Social impacts were further aggregated and analyzed by social themes and impact categories. Results and discussion: The social impacts of the sugarcane life-cycle in Brazil arise almost exclusively within the Brazilian sugarcane sector itself. Fifteen social themes are identified as hotspots in the SHDB, and nine of them are also identified by content Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation analysis. Health and safety, and labour rights and decent work are the impact categories with the highest risks. Besides negative impacts, content analysis is capable of identifying several positive impacts related to sugarcane production. Due to the use of aggregated country-level data, social impacts of manual and mechanical harvesting of sugarcane cannot be differentiated in SHDB; however, this can be achieved by content analysis. Conclusions: SHDB is effective for identifying social impacts at the country level but the data are inevitably aggregated and only show averages across different technologies and geographical areas; therefore, the database is of limited value in distinguishing between alternative operations and locations. Content analysis can facilitate foreground data collection by differentiating operations and identifying both negative and positive impacts at the level of individual activities. We recommend that S-LCA databases can be integrated with results of content analysis to improve the richnessrepresentativity and specificity-of results from a screening S-LCA, to differentiate between alternative production routes and processes.

Flexible and stretchable electronic (FSE) transistors create various novel applications. Carbon nanotubes possess high intrinsic mobility and exceptional mechanical and optical characteristics, which lead to a great potential as channel and electrodes in FSE transistors. At the same time, gate dielectric is also required to be intrinsically flexible/stretchable and integratable. However, few high‐performance solutions have been reported. By adopting polyvinyl alcohol (PVA)/SiO2 hybrid layer as dielectric, the integration of high‐performance intrinsically flexible/stretchable carbon‐nanotube‐based thin film transistors is proposed and realized simply by traditional photolithography‐etching and low‐temperature solution processes. The PVA/SiO2 dielectric simultaneously provides a relatively high‐k value, improves the carrier conduction interface, increases the carbon nanotube (CNT) density, and protects the PVA from plasma damage. Soft transistors with carbon nanotube channel and electrodes exhibit carrier mobility of 14 cm2 V−1 s−1 within an operation voltage of 0.3 V. These transistors show a small bending radius of 3 mm, and the stretchable transistors can withstand 50% strain with no significant electrical degradation observed, when measured in situ and along different directions for more than 1000 cycles. This work provides a solution for soft transparent transistor integration, indicating promising applicability to soft circuits, displays, and wearable electronics.

Through a biomimetic pathway, hyperolactone D, 4-hydroxyhyperolactone D, and hyperolactone C were synthesized from methyl acetoacetate via Weiler's dianion method, asymmetric allylic alkylation, biomimetic lactonization, oxidation, and cyclization. The stereochemistry of the quaternary carbon was controlled efficiently by Palladium-catalyzed asymmetric allylic alkylation. This strategy was also used for the synthesis of hyperolactone B.

In recent years, stretchable electronics have attracted great attention because of their broad application prospects such as in the field of wearable electronics, skin-like electronics, medical transplantation and human–machine interaction.