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ded. The best results were obtained using heat treatment at 570 °C, which produces LS crystals embedded in a glassy matrix (67%) with small contents of secondary phases.Zirconia-based materials veneered with glassy porcelain have become the material of choice for both dentists and their patients. This restoration material is now extensively used in clinical practice for the following reasons material closely resembles tooth appearance, biofunctionality, biocompatibility and affordability. However, premature clinical failures due to the combination of subsurface flaws and tensile stresses within porcelains raise a concern about their reliability and integrity. This study evaluates structural relaxation in dental porcelain to form a suitable explanation for subsurface tensile stresses. Finite Element Method (FEM) is used for this analysis. User material subroutines, UEXPAN, and UTRS, were developed and integrated into a finite element solver to study the effects of structural relaxation on thermal stresses in veneer during final heat treatment. The predictions of the model were validated through qualitative and quantitave means. A validated model was used for Finite Element Analysis (FEA). Faster cooling rates and high veneer thickness predicted high subsurface tensile stresses due to ineffective structural relaxation. Slow cooling rates and lower veneer thickness showed desired compressive stresses in subsurface areas with visible structural relaxation. This work, emphasizing structural relaxation in veneering dental porcelain, provides a way forward for effective designing of dental restorations. Accordingly, it is useful to tailor the desired stress state for extended life in veneered dental porcelains on zirconia frameworks.A solution is obtained for incompressible non-linearly elastic membranes that describes the bending of a cylindrical sector to form a perfect cylinder for a wide class of materials that includes isotropic materials and orthotropic materials reinforced by two families of mechanically equivalent fibres that are wound helically about the axial direction. Despite the relative simplicity of the physical problem, the solution of the corresponding boundary value problem for thick cylinders requires a numerical solution for even the simplest models. It is shown, however, that the thin shell solution provides an excellent approximation to the solution of the problem for cylindrical sectors whose thicknesses are an order of magnitude greater than that assumed for membranes. The approximate stress distribution in such thin shells is obtained. In these residually stressed cylinders, the radial stress is approximately zero but the hoop and axial stresses are finite. Estimates of the residual stresses in the unloaded state are obtained. A closed-form solution for the bending moment necessary to effect the deformation is also obtained.Reductive soil disinfestation (RSD) is an emerging technique that ameliorates soil degradation, but its effects against antibiotic resistance genes (ARGs) were unclear. Here, we examined soil properties, ARG types and numbers, and ARG profiles, and bacterial community compositions following 4 soil treatments control; straw addition (SA); water flooding (WF); and RSD, both straw addition and water flooding. The results showed that the numbers of ARG types and subtypes decreased by 10.8% and 21.1%, respectively, after RSD, and the numbers of ARGs decreased by 18.6%. The attenuated multidrug, beta-lactam, macrolide, and phenicol resistance genes in the RSD soil corresponded to a decreased relative abundance of ARG subtypes (i.e., adeF, mdtM, TypeB_NfxB, mecA, nalC, OXA-60, and cmlA4). Taxa in phyla Proteobacteria, Actinobacteria, and Deinococcus-Thermus were the main hosts for dominant ARG subtypes and were inhibited by RSD. AZD9291 The selected bacterial genera and soil properties explained 83.4% of the variance in ARG composition, suggesting that the improved soil properties and the reduced potential ARG hosts produced by the interactions of straw addition and water flooding are likely responsible for ARG attenuation by RSD. Therefore, RSD has the potential to mitigate ARG pollution in soils.Bioremediation of polychlorinated biphenyls (PCBs) is impeded by difficulties in massively cultivating bioinoculant. Meanwhile, sewage sludge is rich in pollutant-degrading microorganisms and nutrients, drawing our attention to investigate their potential to be used as a supplement for bioremediation of PCBs. Here we reported extensive microbial reductive dechlorination of PCBs by waste activated sludge (WAS) and digestion sludge (DS), which were identified to harbor multiple putative organohalide-respiring bacteria (i.e., Dehalococcoides, Dehalogenimonas, Dehalobacter, and uncultivated Dehalococcoidia) and PCB reductive dehalogenase genes (i.e., pcbA4 and pcbA5). Consequently, amendment of 1-20% (w/w) fresh WAS/DS enhanced the attenuation of PCBs by 126-544% in a soil microcosm compared with the control soil, with the fastest dechlorination of PCBs being achieved when spiked with 20% fresh WAS. Notably, dechlorination pathways of PCBs were also changed by sludge amendment. Microbial and physicochemical analyses revealed that the enhanced dechlorination of PCBs by sludge amendment was largely attributed to the synergistic effects of sludge-derived nutrients, PCB-dechlorinating bacteria, and stimulated growth of beneficial microorganisms (e.g., fermenters). Finally, risk assessment of heavy metals suggests low potential ecological risks of sludge amendment in soil. Collectively, our study demonstrates that sewage sludge amendment could be an efficient, cost-effective and environment-friendly approach for in situ bioremediation of PCBs.Microplastics have attracted widespread attention due to their detrimental effects on organisms, and their efficient removal poses great challenges, especially those smaller than 3 µm that are more harmful for aquatic biota. Herein, the chitin based sponges with interconnected pores, excellent elasticity and mechanical durability were fabricated and composed with graphene oxide (GO) and oxygen-doped carbon nitride (O-C3N4). The chitin based sponges could effectively remove different functionalized microplastics (~1 µm) at pH 6-8, including carboxylate-modified polystyrene (PS-COOH), amine-modified polystyrene (PS-NH2), and polystyrene (PS). Notably, the removal efficiency of three microplastics by the chitin based sponges reached up to 71.6-92.1% at an environmentally relevant concentration of 1 mg L-1 in water system. The potential driving forces of the adsorption were electrostatic interactions, hydrogen bond interactions, and π-π interactions. In addition, the chitin based sponges are reusable and after re-used for 3 cycles due to their excellent compressibility.