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Microbial fuel cell (MFC) systems have been developed for potential use as power sources, along with several other applications, with bacteria as the prime factor enabling electrocatalytic activity. Limited voltage and current production from unit cells limit their practical applicability, so stacking multiple MFCs has been proposed as a way to increase power production. Special attention is paid to voltage reversal (VR), a common occurrence in stacked MFCs, and to identifying the mechanisms underlying this phenomenon. We also proposed realistic perspectives on stacked MFCs in an effort to control and suppress VR by balancing the kinetics in the system, such as using enriched electroactive microorganisms or altering the circuitry mode.

Abstract PhotoVoltaChromic (PVC) cells are among the emerging smart windows technologies with an interesting potential of building integration. PVC technology combines ElectroChromic materials with Dye Sensitized Solar cells in order to have a self-powered adaptive transparent film. The main advantage of this technology is to have an automatic control – potentially manually overridden – of colouration process, depending on levels of solar irradiance. Moreover, a PVC window can operate, at the same time, as a photovoltaic cell, producing energy exceeding the amount required for the colouring process. In the current study, for the first time, the full potential of PVC windows in office buildings is assessed. For this analysis, a PVC cell with a Visible Light Transmittance (VLT) variable between 16.9% and 31.5% has been selected. Australia has been considered as reference location, due to the presence, in its territory, of different climatic regions, ranging from tropical/subtropical climates to the temperate ones. The results show a strong dependence of potential energy savings on Window-to-Wall Ratio (WWR) and solar irradiance on windows. In cooling dominated climates, the adoption of PVC windows has been demonstrated to be always beneficial, even with very low WWR and/or non-optimal exposures, achieving overall energy savings of up to 20%. In heating dominated climates, adoption of PVC windows should be carefully considered, as it is highly beneficial when large glazed surfaces are present. In this case annual total energy savings up to the 32% can be predicted in comparison with buildings equipped with standard clear windows.

Australia, and especially South-Western Australia, is a diversity hotspot for large branchiopod crustaceans. A significant proportion of this diversity is found in the anostracans (Crustacea, Anostraca) and particularly in the diverse genus Branchinella with at least 34 species. Members of this genus are found exclusively in temporary aquatic habitats which are increasingly threatened by secondary salinization and other anthropogenic pressures. The development of adequate conservation strategies is therefore considered a priority. To define conservation units, however, thorough knowledge of the taxonomy and phylogenetic position of extant lineages is essential. We reconstructed a large scale phylogeny of the Australian Branchinella by analyzing the 16S mitochondrial gene of 31 presumed species, complemented with analysis of morphological structures holding taxonomic information. Results revealed the presence of at least three new cryptic species. On the other hand, some Branchinella lineages, surviving in environments subjected to contrasting selection regimes, appeared to be conspecific. This suggests substantial physiological plasticity or important adaptive variation present in some species, potentially enabling them to better cope with environmental change, such as secondary salinization. Overall, these results further illustrate the benefits of combining molecular markers and classic morphological taxonomy and phylogeny to assess biodiversity and define conservation units in cryptic groups.

Abstract Key research effort was dedicated toward zero-energy buildings. Recent interest is switching from single-building to inter-building scale, to enhance the whole district economic-environmental sustainability. This upscaling opens the doors to further optimization strategies thanks to outdoor microclimate mitigation aimed at reducing winter thermal losses and summer overheating. This work proposes a novel design-stage replicable method for multiscale microclimate improvement correlated to building thermal-energy analysis in a residential near-zero-energy district in central Italy. Cool surface installation and conscious greenery design in the outdoors were used in the district of single-family houses. Therefore, a microclimate simulation was performed to elaborate realistic weather files to be used in the second-stage dynamic thermal-energy simulation at building level, in order to evaluate the impact of the local microclimate on building thermal-energy performance and renewables’ production. Microclimate analysis demonstrated how local conditions affect outdoor comfort and that they may be considered in the same way as traditional energy-efficiency improvement early-stage design strategies at building scale, being able to reduce building energy need for HVAC up to 10% in the studied conditions. Therefore, new potentialities of inter-building scale analyses for energy efficiency enhancement and renewable energy exploitation are expected while downscaling microclimate assessment toward building thermal-energy performance.

Bipolar disorder is characterized by a seasonal pattern with emerging evidence that weather conditions may trigger symptoms. Thus, our aims were to investigate if year-to-year variations in admissions with mania correlated with year-to-year variations in key meteorological variables, if there was a secular trend in light of climate change and if gender or admission status influenced the seasonal pattern.We undertook a Danish register-based nationwide historical cohort study. We included all adults hospitalized to psychiatric care from 1995 to 2012 with mania using the Danish Psychiatric Central Research Register. The Danish Meteorological Institute provided the meteorological variables. The association between weather and admissions was tested using linear regression.Our database comprised 24,313 admissions with mania. There was a seasonal pattern with admission rates peaking in summer. Higher admission rates were associated with more sunshine, more ultraviolet radiation, higher temperature and less snow but were unassociated with rainfall. We did not find a secular trend in the seasonal pattern. Finally, neither gender nor admission status impacted on the overall seasonal pattern of admissions with mania.Only patients in psychiatric care were included. We could not subdivide by type of bipolar disorder.This cohort study based on more than 24,000 admissions identified a distinct seasonal pattern in hospital admissions for those with mania. We found no secular trend. This could indicate that the climate change is not impacting on seasonal patterns, that there is no link between the proposed variables or that change is currently not sufficiently distinctive.

Abstract Neutron-moderator scattering interactions in the thermal energy range are often treated with specialised cross section data derived from the Thermal Scattering Law S(α,β). This scattering law is calculated based on theoretical and experimental models that describe the structure and dynamics of the principle moderator molecule. In this work, a perturbation scheme based on the Total Monte Carlo method is described and the uncertainties of the parameters used to calculate S(α,β) for H in H2O and D and O in D2O from the ENDF/B-VIII.0 library were estimated and propagated through to the cross sections and to an integral criticality scenario in the OPAL Reactor, Sydney Australia, using the transport code Serpent. The calculated uncertainties in the total cross sections are in reasonable agreement with experimental data and provide a basis for future model refinement; uncertainties in several parameters used in the LEAPR of NJOY were identified as critical to specific energy regions and behaviours of the total cross sections. The effect on criticality of these uncertainties was found to be 48 pcm and 41 pcm for H2O and D2O, respectively, within the OPAL Reactor during a low-power configuration.

Danish district heating systems have good water quality, but continue to suffer from biofouling and biocorrosion. Localisation analyses of bacteria using microautoradiography were performed for one system in order to obtain detailed information for solving these problems. A mass balance showed that 77% of the bacteria were located at surfaces, with 23% in the bulk water, and 9% of the total carbon originated from biomass, while 91% was dissolved in the bulk water. The presence of active bacteria was determined with microautoradiography which showed that biofilms contained 99% and 1% were in the bulk water. A high bacterial functional diversity was observed, with active mesophilic and thermophilic bacteria under aerobic and anaerobic conditions and with potentially corrosive biofilm bacteria present. The study reveals that by applying the activity based approach, the ratio of living and dead bacteria in the biofilm and bulk water in this type of system could be accurately determined. Also, the results emphasise that to minimise biofilm growth and biocorrosion, monitoring should be established focusing on the surfaces, since bulk water parameters do not reflect bacterial activity.