Techniques and crops for efficient rooftop gardens in Bologna, Italy

Urban rooftop farming favours local food production. Although rooftop farming is perceived as 33 a sustainable system, there is a lack of quantitative studies on rooftop farming. There we set up 34 experiments in the community rooftop garden of a public housing building in Bologna, Italy, 35 between 2012 and 2014. We grew lettuce, a leafy vegetable, using three techniques: nutrient 36 film, floating hydroponic and soil cultivation. We also grew tomato, chilli pepper, eggplant, 37 melon, watermelon on soils. Data was analysed by life cycle assessment for environmental and 38 economic performance. Results reveal that the best techniques of lettuce cultivation to address 39 global warming were floating in the summer, with 65-85% less environmental impact per kg 40 than nutrient film; and soil production in the winter, with 85-95% less environmental impact. 41 Furthermore, floating production was 25% cheaper in summer and soil was 65% cheaper in 42 winter, compared to the nutrient film technique. For soil production, eggplants and tomatoes 43 showed the best environmental performances of about 74 g CO2 per kg. Eggplant production in 44 soil gave in the cheapest crop of 0.13 € per kg

Aquaponics in the Built Environment

Aquaponics’ potential to transform urban food production has been documented in a rapid increase of academic research and public interest in the field. To translate this publicity into real-world impact, the creation of commercial farms and their relationship to the urban environment have to be further examined. This research has to bridge the gap between existing literature on growing system performance and urban metabolic flows by considering the built form of aquaponic farms. To assess the potential for urban integration of aquaponics, existing case studies are classified by the typology of their building enclosure, with the two main categories being greenhouses and indoor environments. This classification allows for some assumptions about the farms’ performance in their context, but a more in-depth life cycle assessment (LCA) is necessary to evaluate different configurations. The LCA approach is presented as a way to inventory design criteria and respective strategies which can influence the environmental impact of aquaponic systems in the context of urban built environments

Arabidopsis DEAD-box RNA helicase UAP56 interacts with both RNA and DNA as well as with mRNA export factors

The DEAD-box protein UAP56 (U2AF65-associcated protein) is an RNA helicase that in yeast and metazoa is critically involved in mRNA splicing and export. In Arabidopsis, two adjacent genes code for an identical UAP56 protein, and both genes are expressed. In case one of the genes is inactivated by a T-DNA insertion, wild type transcript level is maintained by the other intact gene. In contrast to other organisms that are severely affected by elevated UAP56 levels, Arabidopsis plants that overexpress UAP56 have wild type appearance. UAP56 localises predominantly to euchromatic regions of Arabidopsis nuclei, and associates with genes transcribed by RNA polymerase II independently from the presence of introns, while it is not detected at non-transcribed loci. Biochemical characterisation revealed that in addition to ssRNA and dsRNA, UAP56 interacts with dsDNA, but not with ssDNA. Moreover, the enzyme displays ATPase activity that is stimulated by RNA and dsDNA and it has ATP-dependent RNA helicase activity unwinding dsRNA, whereas it does not unwind dsDNA. Protein interaction studies showed that UAP56 directly interacts with the mRNA export factors ALY2 and MOS11, suggesting that it is involved in mRNA export from plant cell nuclei