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AbstractWe report the design, synthesis and evaluation of dynamic “octopus” amphiphiles with emphasis on their efficiency as activators in synthetic membrane‐based sensing systems. Previously, we found that the in situ treatment of charged hydrazides with hydrophobic aldehydes or ketones gives amphiphilic counterion activators of polyion transporters in lipid bilayers, and that their efficiency increases with the number of their hydrophobic tails. Herein, we expand this series to amphiphiles with one cationic head (guanidinium or ammonium) and four exchangeable hydrophobic tails. These results, with the highest number of tails reported to date, confirm that dynamic octopus amphiphiles provide access to maximal activity and selectivity. Odorants, such as muscone, carvone, or anisaldehyde are used to outline their usefulness in differential sensing systems that operate based on counterion‐activated DNA transporters in fluorogenic vesicles. The enhanced ability of octopus amphiphiles to enable the discrimination of enantiomers as well as that of otherwise intractable ortho, meta, and para isomers and short cyclo‐/alkyl tails is demonstrated. These findings identify dynamic octopus amphiphiles as being promising for application to differential sensing, “fragrant” cellular uptake, and slow release.

AbstractWe report the design, synthesis and evaluation of dynamic “octopus” amphiphiles with emphasis on their efficiency as activators in synthetic membrane‐based sensing systems. Previously, we found that the in situ treatment of charged hydrazides with hydrophobic aldehydes or ketones gives amphiphilic counterion activators of polyion transporters in lipid bilayers, and that their efficiency increases with the number of their hydrophobic tails. Herein, we expand this series to amphiphiles with one cationic head (guanidinium or ammonium) and four exchangeable hydrophobic tails. These results, with the highest number of tails reported to date, confirm that dynamic octopus amphiphiles provide access to maximal activity and selectivity. Odorants, such as muscone, carvone, or anisaldehyde are used to outline their usefulness in differential sensing systems that operate based on counterion‐activated DNA transporters in fluorogenic vesicles. The enhanced ability of octopus amphiphiles to enable the discrimination of enantiomers as well as that of otherwise intractable ortho, meta, and para isomers and short cyclo‐/alkyl tails is demonstrated. These findings identify dynamic octopus amphiphiles as being promising for application to differential sensing, “fragrant” cellular uptake, and slow release.

Questions of justice in the transition to a green economy have been raised by various social forces. Very few proposals, however, have been as focused and developed as the “just transition” strategy proposed by global labour unions. Yet, labour unions are remarkably absent from discussions of the transition towards a green economy. This is surprising as labour unions are arguably the largest organizations in the world fighting for basic rights and more just social relations. This paper tries to advance the potential contribution of labour unions in this arena by asking: what is the full scope of “just transition” today and how have labour unions developed and refined it over the years to render the move towards a green economy both environmentally and socially sustainable? The concept of just transition is hotly debated within labour unions and has different interpretations, and hence different strategies. The last section assesses these interpretations by means of a normative framework, which seeks to fuse political economy and political ecology. Empirically, we add to the growing literature on labour environmentalism, as well as transitions more generally. Analytically, our goal is to place the various approaches to a “just transition” within a heuristic framework of environmental justice that is explicit about power relations when demanding justice, two themes central to this special issue.

Questions of justice in the transition to a green economy have been raised by various social forces. Very few proposals, however, have been as focused and developed as the “just transition” strategy proposed by global labour unions. Yet, labour unions are remarkably absent from discussions of the transition towards a green economy. This is surprising as labour unions are arguably the largest organizations in the world fighting for basic rights and more just social relations. This paper tries to advance the potential contribution of labour unions in this arena by asking: what is the full scope of “just transition” today and how have labour unions developed and refined it over the years to render the move towards a green economy both environmentally and socially sustainable? The concept of just transition is hotly debated within labour unions and has different interpretations, and hence different strategies. The last section assesses these interpretations by means of a normative framework, which seeks to fuse political economy and political ecology. Empirically, we add to the growing literature on labour environmentalism, as well as transitions more generally. Analytically, our goal is to place the various approaches to a “just transition” within a heuristic framework of environmental justice that is explicit about power relations when demanding justice, two themes central to this special issue.

AbstractA metal‐free organic sensitizer, suitable for the application in dye‐sensitized solar cells (DSSCs), has been designed, synthesized and characterized both experimentally and theoretically. The structure of the novel donor–acceptor–π‐bridge–acceptor (D–A–π–A) dye incorporates a triphenylamine (TPA) segment and 4‐(benzo[c][1,2,5]thiadiazol‐4‐ylethynyl)benzoic acid (BTEBA). The triphenylamine unit is widely used as an electron donor for photosensitizers, owing to its nonplanar molecular configuration and excellent electron‐donating capability, whereas 4‐(benzo[c][1,2,5]thiadiazol‐4‐ylethynyl)benzoic acid is used as an electron acceptor unit. The influences of I3−/I−, [Co(bpy)3]3+/2+ and [Cu(tmby)2]2+/+ (tmby=4,4′,6,6′‐tetramethyl‐2,2′‐bipyridine) as redox electrolytes on the DSSC device performance were also investigated. The maximal monochromatic incident photon‐to‐current conversion efficiency (IPCE) reached 81 % and the solar light to electrical energy conversion efficiency of devices with [Cu(tmby)2]2+/+ reached 7.15 %. The devices with [Co(bpy)3]3+/2+ and I3−/I− electrolytes gave efficiencies of 5.22 % and 6.14 %, respectively. The lowest device performance with a [Co(bpy)3]3+/2+‐based electrolyte is attributed to increased charge recombination.

AbstractA metal‐free organic sensitizer, suitable for the application in dye‐sensitized solar cells (DSSCs), has been designed, synthesized and characterized both experimentally and theoretically. The structure of the novel donor–acceptor–π‐bridge–acceptor (D–A–π–A) dye incorporates a triphenylamine (TPA) segment and 4‐(benzo[c][1,2,5]thiadiazol‐4‐ylethynyl)benzoic acid (BTEBA). The triphenylamine unit is widely used as an electron donor for photosensitizers, owing to its nonplanar molecular configuration and excellent electron‐donating capability, whereas 4‐(benzo[c][1,2,5]thiadiazol‐4‐ylethynyl)benzoic acid is used as an electron acceptor unit. The influences of I3−/I−, [Co(bpy)3]3+/2+ and [Cu(tmby)2]2+/+ (tmby=4,4′,6,6′‐tetramethyl‐2,2′‐bipyridine) as redox electrolytes on the DSSC device performance were also investigated. The maximal monochromatic incident photon‐to‐current conversion efficiency (IPCE) reached 81 % and the solar light to electrical energy conversion efficiency of devices with [Cu(tmby)2]2+/+ reached 7.15 %. The devices with [Co(bpy)3]3+/2+ and I3−/I− electrolytes gave efficiencies of 5.22 % and 6.14 %, respectively. The lowest device performance with a [Co(bpy)3]3+/2+‐based electrolyte is attributed to increased charge recombination.

AbstractRebuilding overexploited marine populations is an important step to achieve the United Nations' Sustainable Development Goal 14—Life Below Water. Mitigating major human pressures is required to achieve rebuilding goals. Climate change is one such key pressure, impacting fish and invertebrate populations by changing their biomass and biogeography. Here, combining projection from a dynamic bioclimate envelope model with published estimates of status of exploited populations from a catch‐based analysis, we analyze the effects of different global warming and fishing levels on biomass rebuilding for the exploited species in 226 marine ecoregions of the world. Fifty three percent (121) of the marine ecoregions have significant (at 5% level) relationship between biomass and global warming level. Without climate change and under a target fishing mortality rate relative to the level required for maximum sustainable yield of 0.75, we project biomass rebuilding of 1.7–2.7 times (interquartile range) of current (average 2014–2018) levels across marine ecoregions. When global warming level is at 1.5 and 2.6°C, respectively, such biomass rebuilding drops to 1.4–2.0 and 1.1–1.5 times of current levels, with 10% and 25% of the ecoregions showing no biomass rebuilding, respectively. Marine ecoregions where biomass rebuilding is largely impacted by climate change are in West Africa, the Indo‐Pacific, the central and south Pacific, and the Eastern Tropical Pacific. Coastal communities in these ecoregions are highly dependent on fisheries for livelihoods and nutrition security. Lowering the targeted fishing level and keeping global warming below 1.5°C are projected to enable more climate‐sensitive ecoregions to rebuild biomass. However, our findings also underscore the need to resolve trade‐offs between climate‐resilient biomass rebuilding and the high near‐term demand for seafood to support the well‐being of coastal communities across the tropics.

AbstractRebuilding overexploited marine populations is an important step to achieve the United Nations' Sustainable Development Goal 14—Life Below Water. Mitigating major human pressures is required to achieve rebuilding goals. Climate change is one such key pressure, impacting fish and invertebrate populations by changing their biomass and biogeography. Here, combining projection from a dynamic bioclimate envelope model with published estimates of status of exploited populations from a catch‐based analysis, we analyze the effects of different global warming and fishing levels on biomass rebuilding for the exploited species in 226 marine ecoregions of the world. Fifty three percent (121) of the marine ecoregions have significant (at 5% level) relationship between biomass and global warming level. Without climate change and under a target fishing mortality rate relative to the level required for maximum sustainable yield of 0.75, we project biomass rebuilding of 1.7–2.7 times (interquartile range) of current (average 2014–2018) levels across marine ecoregions. When global warming level is at 1.5 and 2.6°C, respectively, such biomass rebuilding drops to 1.4–2.0 and 1.1–1.5 times of current levels, with 10% and 25% of the ecoregions showing no biomass rebuilding, respectively. Marine ecoregions where biomass rebuilding is largely impacted by climate change are in West Africa, the Indo‐Pacific, the central and south Pacific, and the Eastern Tropical Pacific. Coastal communities in these ecoregions are highly dependent on fisheries for livelihoods and nutrition security. Lowering the targeted fishing level and keeping global warming below 1.5°C are projected to enable more climate‐sensitive ecoregions to rebuild biomass. However, our findings also underscore the need to resolve trade‐offs between climate‐resilient biomass rebuilding and the high near‐term demand for seafood to support the well‐being of coastal communities across the tropics.