Efficient catalytic gasification is essential for improving producer gas quality by enhancing tar destruction, and thus more sustainable biomass-to-energy pathways. Iron oxides and spinel ferrites (MFe2O4) have attracted attention as gasification catalysts due to their redox versatility and structural stability, with the divalent cation playing a crucial role in oxygen mobility and metal-oxygen bond strength. In this work, the effect of Co and Mn as divalent cations in spinel ferrites was investigated and compared with hematite during biomass gasification. Catalysts were synthesized via wet impregnation method combined with microwave-assisted calcination, and characterized by XRD, XRF, BET, SEM/EDS, TGA, and Raman. Their performance was evaluated following the improvement of gas quality during gasification of residual forest biomass in a bench-scale bubbling fluidized bed reactor. The gasification conditions were 850 °C, equivalence ratio of 0.25 and air as gasifying agent. The results show that catalytic activity for gas quality improvement followed the sequence CoFe2O4 > MnFe2O4 > Fe2O3, mainly due to differences in M − O bond strength and redox flexibility. The Co-based catalyst exhibited the highest performance, increasing the H2 production by 115% and the H2:CO molar ratio by 95%, while decreasing tar production by 66% relative to the reference condition. Process parameters such as CGE, CCE, gas yield and LHV were less affected by the catalyst than the producer gas composition. These results show the positive effect of divalent cations in spinel ferrites and contribute to the rational design of catalysts for efficient biomass to syngas conversion.
Although it is known that workspace influences the performance of healthcare teams, there is scarce evidence regarding how to evaluate its implications for resilient performance. This study demonstrates an integrated approach for evaluating the effects of relocating three acute response teams responsible for the same patients – the rapid response team (RRT), medical on-call team (MOC), and nursing supervision (NS) – from separate rooms to a shared workspace. The intervention was evaluated using two complementary sources of evidence. First, social network analysis surveys were conducted before and after the intervention with the same 30 participants. The surveys mapped advice-seeking relationships from which 22 social network metrics were derived. Second, seven organizational quality indicators were analyzed before and after the intervention. Five quality and 12 network indicators showed statistically significant improvements; except for two social network metrics, all 27 indicators changed in the expected direction for improvement. Notably, reciprocity between teams, which is crucial for resilience, increased substantially – e.g., RRT↔MOC increased from 57.5% to 80.0%. Changes in collaboration patterns and quality indicators provided complementary evidence that the conditions supporting resilient performance were enhanced. The evaluation approach can be adapted to other resilience-oriented interventions in which relational dynamics and patient safety are crucial.
Anthropogenic land-use change drives biodiversity loss by altering habitat structure, reducing connectivity, and reshaping ecological processes, even within protected areas. Although protected areas are key for biodiversity conservation, their effectiveness may depend on the surrounding landscape context. This study evaluates the effects of land use around and within protected areas on species richness and functional diversity in amphibian assemblage. Data were collected during 12 monthly expeditions between January 2013 and December 2014, sampling 81 ponds across eight protected areas and surrounding landscapes in southern Brazil. We measured species richness, abundance, and 21 ecomorphological traits, using phylogenetic eigenvector regression to control phylogenetic autocorrelation. Functional diversity was estimated as the total branch length of functional dendrograms. Structural equation modelling was used to assess the effects of spatial, landscape, land use, and habitat variables on species richness, abundance, and functional diversity. Land use, hydroperiod, and spatial configuration shaped amphibian assemblages through different mechanisms. Species richness was mainly driven by vegetation heterogeneity in ponds, abundance and pond connectivity, whereas functional diversity responded to land use, native landscape and hydroperiod. Anthropogenic land use (e.g., agriculture and reforestation) was positively associated with functional diversity, likely reflecting shifts toward generalist and disturbance-tolerant species rather than improved environmental conditions. Overall, our results show that different diversity dimensions respond to distinct drivers, and that land-use change can reorganize functional structure. We highlight the importance of conserving interconnected ponds with diverse hydroperiods and high vegetation heterogeneity within and around protected areas to maintain amphibian diversity and avoid long-term functional homogenization.
This study aimed to evaluate the use of sludge from the processing of ornamental rocks and calcium carbonate sludge as filler, replacing limestone up to 15
Environmental filtering and limiting similarity are two important ecological processes that drive species abundance distribution. However, little is known about the influence of these processes on the assembly of phytoplankton communities in eutrophic ecosystems over the time. Here, we evaluated the relationships between species relative abundances and ecological dissimilarity, surface-to-volume ratio, and volume differences for phytoplankton communities over 21 years, in a shallow tropical eutrophic reservoir. Further, we tested the influence of environmental variability over time on the strength of these relationships. We found a negative relationship between relative abundance and surface-to-volume ratio and volume differences between species, that is, the most abundant species in phytoplankton communities tended to be similar in these body size traits. Our findings evidenced that species abundance distribution was more consistent with the environmental filtering processes than with limiting similarity. Furthermore, we discovered that these relationships are weakened with the increase in water transparency and strengthened with the increase of soluble reactive phosphorus concentration. These results are probably related to the fact that the reservoir has a highly specialized pool of species. Our outcomes emphasize that in a nutrient-rich environment and during cyanobacterial blooms, species coexistence over time relies significantly on niche similarity and surface:volume ratio and volume.
