The aim of this study was to characterize the degree of conversion and the bond strength of experimental adhesive systems formulated with elastomeric monomers (Exothanes). Two-step self-etch adhesive systems were formulated, where the primer was constituted by HEMA, HEMA-P, water and ethanol, and the resin bonds were prepared mixing one type of Exothane (8, 9, 10, 24, or 32) (75 wt%) with TEGDMA (25 wt%). CQ, EDAB, and DPI were added as photo-initiation system. UDMA was used as control, so six different resin bonds were formulated at all. The adhesive system Clearfil SE Bond (CLSE) was used as a commercial control. The degree of conversion (DC) of each resin bond was evaluated in infrared spectroscopy (RT-FTIR, Shimadzu Prestige-21) using a diamond crystal (n = 3). The microshear bond strength (μSBS) test was performed using a universal testing machine (EMIC DL-500). While the DC data was analyzed by one-way ANOVA and Tukey (p < 0.05), the μSBS data was analyzed by Kruskal-Wallis test and Student-NewmanKeuls (p < 0.05). The resin bonds containing the Exothanes 8, 9, and 32 demonstrated DC values higher than 80%, differently to the other Exothane-based adhesives, which showed DC values close to 50%. UDMA and CLSE demonstrated lower DC than E 8 , E 9 , and E 32 (p < 0.001). The Exothane 24 resulted in the lowest DC value of the study (p < 0.001), although it was similar to the E 10 and UDMA adhesives (p > 0.05). Low μSBS results were seen for the Exothane-based materials. CLSE demonstrated significantly higher bond strength than the other materials (p < 0.001). UDMA has also presented low μSBS to the dentin substrate. It can be concluded that the Exothanes evaluated demonstrated satisfactory degree of conversion, with some of them reaching almost full conversion of monomers in polymer. However, considering the formulations investigated, they were not good bonding agents. So, they were not reliable options for composing the polymeric matrix of dental adhesive materials.

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This study aimed to propose an eco-compatible strategy to mitigate the possible environmental contamination caused by tebuthiuron. Therefore, we screened potential tebuthiuron-degrading microorganisms from conventional (CS) and no-till (NTS) systems producing sugarcane. Then, they were bioprospected for their ability of decomposing the target-molecule at 2.48 mmol g−1 and 4.96 mmol g−1 into CO2 via respirometry. Integrating microbiota from CS and NTS into an advantageously synergistic bacterial pool produced the highest specific-growth rate of CO2 of 89.60 mg day−1, so outstripped the other inoculum. The bacterial CN-NTS framework notably stabilized the sigmoidal Gompertz curve on microbial degradation earliest and enabled the seeds of Lactucasativa to germinate healthiest throughout ecotoxicological bioassay for cross-validation. Our study is preliminary, but timely to provide knowledge of particular relevance to progress in the field's prominence in remediating terrestrial ecosystems where residual tebuthiuron can persist and contaminate. The analytical insights will act as an opening of solutions to develop high-throughput biotechnological strategies for environmental decontamination.

Synthetic fertilization can increase maize yields, but also cause environmental impacts, as well as increasing production costs and food security risks. Sun mushroom (Agaricus subrufescens) is an important Brazilian fungus used to generate large amounts of spent mushroom substrate. This residue can be used for maize fertilization, but little is known about its ideal application rates to reduce maize dependence on synthetic fertilizers. Therefore, this study aimed to evaluate the agronomic performance of a maize crop under different combinations of synthetic fertilizers and two different spent mushroom substrate doses. The experiment was carried out in pots and evaluated maize germinate and biometric parameters, as well as soil and leaf chemical characteristics. The results showed that residue application increased maize germination and Emergence Speed Index. Regarding the maize biometric parameters, height, stem diameter, shoot fresh and dry masses, and leaf area were superior for residue with synthetic fertilization at sowing only at higher doses. Moreover, residue with synthetic fertilization at sowing proved to be more relevant for maize growth according to canonical discriminant analysis. In terms of nutrients, the use of spent mushroom substrate increased significantly leaf P, K, and S levels and mainly K content in the soil, justifying non-application at maize topdressing.

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