Environmental performance of Cantabrian (Northern Spain) pelagic fisheries: Assessment of purse seine and minor art fleets under a life cycle approach.

The perpetuation of fishing activity from an environmentally, socially and economically sustainable approach is essential to guarantee not only the future of coastal populations, but also the supply of high-value seafood for society and the safeguarding of cultural heritage. This article aims to assess the environmental performance associated with fishing fleet operations in Cantabria (northern Spain) under a life cycle thinking from a holistic approach. Thus, the Life Cycle Assessment (LCA) methodology was applied under a 'cradle-to-port' approach, setting the functional unit as 1 kg of fresh fish landed. Inventory data on the main inputs and outputs were collected from a sample of 57 vessels covering for the first time the main techniques, purse seine and minor art fisheries. The results identified that the vessel use stage was the responsible of most of the impacts. In line with the literature, diesel consumption stood as the chief hotspot in six of the seven impact categories analysed. Purse seiners got a value of 0.25 kg of fuel per kg of fish landed, while the performance of the minor art fleet showed significantly lower consumption (0.07). Regarding impacts on climate change, this study found a quantity of 1.00 and 0.34 kg CO2 eq. per FU, for purse seine and minor arts, respectively. These figures were consistent with the expected results for pelagic fisheries. For the remaining indicators, purse seiners generally performed worse. The LCA methodology provided outcomes that allow the proposal of potential improvements and measures to foster the transition towards a more sustainable smart-fishing sector. Further research efforts should focus on the development and implementation of renewable energy and low-carbon vessel propulsion technologies.

Computational Investigation of Substituent Effects on the Formation and Intramolecular Cyclization of 2'-Arylbenzaldehyde and 2'-Arylacetophenone Oxime Ether Radical Cations.

This work describes our computational study of substituent effects on the formation and cyclization of 2'-arylbenzaldehyde and 2'-arylacetophenone oxime ether radical cations. Recent experimental work by de Lijser and co-workers has demonstrated that these reactive intermediates, which are generated through photoinduced electron transfer (PET) with a photosensitizer, undergo intramolecular cyclization to yield substituted phenanthridines. The experimental study further showed correlations between the yield of cyclized products and the Hammett σPara+ parameter of the substituent on the aryl group, with both strongly electron-withdrawing and electron-donating substituents shown to significantly reduce the product yield. By analyzing the ΔGPET associated with radical cation formation as well as the thermodynamics and kinetics of radical cation cyclization, we provide an explanation for these observations. We then computationally extend this mechanistic analysis to 2'-arylbenzaldehyde oxime ethers with substituents also present on the central benzene ring and show that such substituents generally have a larger impact on the PET-induced cyclization than those on the aryl group. Overall, this work extends our understanding of the overall scope of this photooxidative route toward substituted phenanthridines as well as makes clear predictions as to how the formation of oxime ether radical cations can be tuned by substituents.