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Whole genome duplication (WGD) can promote adaptation but is disruptive to conserved processes, especially meiosis. Studies in Arabidopsis arenosa revealed a coordinated evolutionary response to WGD involving interacting proteins controlling meiotic crossovers, which are minimized in an autotetraploid (within-species polyploid) to avoid missegregation. Here, we test whether this surprising flexibility of a conserved essential process, meiosis, is recapitulated in an independent WGD system, Cardamine amara, 17 My diverged from A. arenosa. We assess meiotic stability and perform population-based scans for positive selection, contrasting the genomic response to WGD in C. amara with that of A. arenosa. We found in C. amara the strongest selection signals at genes with predicted functions thought important to adaptation to WGD: meiosis, chromosome remodeling, cell cycle, and ion transport. However, genomic responses to WGD in the two species differ: minimal ortholog-level convergence emerged, with none of the meiosis genes found in A. arenosa exhibiting strong signal in C. amara. This is consistent with our observations of lower meiotic stability and occasional clonal spreading in diploid C. amara, suggesting that nascent C. amara autotetraploid lineages were preadapted by their diploid lifestyle to survive while enduring reduced meiotic fidelity. However, in contrast to a lack of ortholog convergence, we see process-level and network convergence in DNA management, chromosome organization, stress signaling, and ion homeostasis processes. This gives the first insight into the salient adaptations required to meet the challenges of a WGD state and shows that autopolyploids can utilize multiple evolutionary trajectories to adapt to WGD.

Whole genome duplication (WGD) occurs across kingdoms and can promote adaptation. However, the sudden increase in chromosome number, as well as immediate changes in cellular physiology, are traumatic to conserved cellular processes. Previous work in Arabidopsis arenosa revealed a clearly coordinated genomic response to WGD, involving a set of functionally and physically interacting proteins mediating crossover number and distribution during prophase I of meiosis. Here we ask: is this highly coordinated coevolutionary shift repeated in other species? We also test globally for convergence for all processes under selection in independent cases of adaptation to WGD, as other processes were under selection in A. arenosa and may be common to other independent adaptation events following WGD. Taking advantage of a well-characterised diploid/autopolyploid system, Cardamine amara , we test our hypothesis that convergence will be detected in the form of directional selection. We also investigate at what level convergence may be evident: identical genes, networks, or analogous processes. To do this we performed a genome scan between diploid and autotetraploid populations, while utilising a quartet-based sampling design to minimise false positives. Among the genes exhibiting the strongest signatures of selection in C. amara autotetraploids we detect an enrichment for DNA maintenance, chromosome organisation, and meiosis, as well as stress signalling. We find that gene-level convergence between the independent WGD adaptation events in C. amara and A. arenosa is negligible, with no more orthologous genes in common than would be expected by chance. In contrast to this, however, we observe very strong convergence at the level of functional processes and homologous (but not orthologous) genes. Taken together, our results indicate that these two autopolyploids survived the challenges attendant to WGD by modifying similar or identical processes through different molecular players and gives the first insight into the salient adaptations required to cope with a genome-doubled state.

Methanogenic communities play a crucial role in carbon cycling and biotechnology (anaerobic digestion), but our understanding of how their diversity, or composition in general, determines the rate of methane production is very limited. Studies to date have been correlational because of the difficulty in cultivating their constituent species in pure culture. Here, we investigate the causal link between methanogenesis and diversity in laboratory anaerobic digesters by experimentally manipulating the diversity of cultures by dilution and subsequent equilibration of biomass. This process necessarily leads to the loss of the rarer species from communities. We find a positive relationship between methane production and the number of taxa, with little evidence of functional saturation, suggesting that rare species play an important role in methane‐producing communities. No correlations were found between the initial composition and methane production across natural communities, but a positive relationship between species richness and methane production emerged following ecological selection imposed by the laboratory conditions. Our data suggest methanogenic communities show little functional redundancy, and hence, any loss of diversity—both natural and resulting from changes in propagation conditions during anaerobic digestion—is likely to reduce methane production.

The concept of Shared Space Street Shared Space Street (SSS) has the potential to bring many benefits to a city. Those include promotion of social interaction, the connectivity within the city for both vehicles and pedestrians, active engagement of the people with the space, walkability, vitality and street livability, better economic wealth and alike. These factors work together to improve livability, vitality of street and indirectly bring economic wealth to municipalities through increasing the footfall to shops, enhancing the health and safety of the locality and increasing the property values. Hence, this clearly is a consideration for strategic property management and relevant professionals. However, This concept has also been criticized for its practical issues when implemented in some parts of the world. Such issues include difficulties faced by aged people and people with disabilities, harassment faced by the cyclists, etc. This paper explores the methods and approaches that can be used to harness potential advantages of the SSS concept and to overcome its practical issues and criticisms through a detail evaluation of design driven use of space in three case studies within United Kingdom. Finally, this paper proposes a set of design factors which can be applied to a SSS design in order to ensure a successful implementation.

Buildings often adopt strategies based on the integration of solutions and technologies in façades capable of changing their behaviour in time to improve energy efficiency and comfort. Considering that the envelope is the main parameter that influences the energy performance of buildings, façade elements with adaptive features can provide the buildings the necessary flexibility needed in terms of energy flow and thermal comfort in the context of nZEB, where the buildings must be interactive in the zero energy and smart city context. Several different types of adaptive façade concepts have already been developed, and an increase in emerging, innovative solutions is expected in the near future. However, when referring to adaptive technologies, two main categories can be distinguished. Adaptive technologies, which rely on passive design to improve building energy efficiency and comfort, and active technologies which include renewable harvesting. The aim of this paper is to provide several examples of passive adaptive technologies and their performance features from COST TU1403 Working Group 1 database. info:eu-repo/semantics/publishedVersion