Purpose To evaluate the influence of a 25% alpha-tocopherol antioxidant gel (AT) and a 50% DL-α-lipoic acid antioxidant solution (AL) on coronal fracture resistance and the integrity of the adhesive interface between coronal dentin and a universal adhesive system (Ambar Universal APS), compared with a 10% sodium ascorbate gel (AS), after internal bleaching with 35% or 40% hydrogen peroxide. Materials and methods Two hundred bovine incisors were used: 80 teeth for fracture resistance and fracture pattern analyses, 80 crowns for resin tag evaluation, and 40 crowns for microtensile bond strength and failure mode analyses. Specimens were allocated according to hydrogen peroxide concentration (35% or 40%) and antioxidant protocol: control (CO), sodium ascorbate (AS), alpha-tocopherol (AT), and DL-α-lipoic acid (AL). Data were analyzed using appropriate statistical tests with a significance level of 5%. Results Sodium ascorbate and alpha-tocopherol exhibited the highest fracture resistance and microtensile bond strength values, whereas sodium ascorbate promoted the greatest resin tag formation. The control groups showed the lowest values for the evaluated mechanical and adhesive properties. DL-α-lipoic acid demonstrated intermediate performance. No significant differences were observed between the 35% and 40% hydrogen peroxide protocols. Conclusion The application of antioxidants after intracoronal bleaching resulted in higher fracture resistance and bond strength compared with the bleached control protocols. Under the experimental conditions evaluated, the sodium ascorbate and alpha-tocopherol protocols showed the most favorable overall performance.
The compositional heterogeneity of agro-industrial byproducts presents a significant challenge for engineering high-performance bio-based materials without resource-intensive macromolecular separation. Here, an eco-efficient strategy is proposed for the comprehensive valorization of whole mango byproducts (MBPs), including peels and finisher pulp (PeP), seed tegument (SeT), and kernel (SeK), into functional bioplastics intended for food packaging. To disrupt the organized biomass structure for subsequent assembly into films, MBPs were subjected to mild hydrothermal pretreatment (HTP) or dilute alkaline pretreatment (DALP), which selectively partitioned amorphous biomass components and induced distinct structural responses according to the mango byproduct. While HTP better preserved solubilized carbohydrates, DALP promoted more extensive pectin saponification and hemicellulose solubilization. Bioplastic films were then prepared using pretreated PeP, SeK, or a mixture of all byproducts (PePSe). The incorporation of only 10% carboxymethyl cellulose (CMC) improved film mechanical performance, yielding tensile strength values of up to 11 MPa. The SeK-based films exhibited the lowest water vapor permeability (2.3 g mm kPa−1 h−1 m−2), and all CMC-containing films displayed hydrophobic surfaces (water contact angle > 90°). All bioplastics provided near-total UVA and UVB shielding (>97%), while the PeP-based films exhibited the highest transparency (>43%). Although the antioxidant activity of the bioplastics decreased compared to that of the corresponding raw MBPs, the PeP-DALP-CMC film retained at least 50% of it. By demonstrating that biomass heterogeneity can be harnessed, rather than eliminated, to tailor functional bioplastics, this simple and effective approach emerges as a potentially scalable strategy for producing sustainable active packaging materials.
Risk management (RM) has been widely studied and adopted as a solution for predicting rapid market changes, increasing industrial and social security, preserving the environment, and preventing disasters. Thus, risk management has become a strategic element for the competitiveness and sustained development of organizations. RM enables the identification, analysis, evaluation, and treatment of risks that affect the organization’s objectives, positively or negatively. This work was developed using the Integrative Review method, which enabled an integrated review, critique, and synthesis of the literature on RM, based on analyses of patents and websites from governments, companies, and research institutes. With this, a new block of RM knowledge was created from the triangulation of information from the main drivers of innovation in society, expanding the existing studies on the subject and providing a basis for further research. As an applied contribution, this study will promote the implementation of RM across governments, companies, and universities, thereby reducing work accidents and environmental incidents, lowering costs, improving productivity, and, consequently, helping organizations consistently achieve their objectives and goals.
Antimicrobial activity of Plasma-Activated Water (PAW) generated using a coaxial Dielectric Barrier Discharge (DBD) reactor was investigated against Enterococcus faecalis and Candida albicans, two microorganisms frequently associated with endodontic treatment failure. PAW was produced using three different working gases such as compressed air (PAW-Ca), argon (PAW-Ar), and helium (PAW-He) resulting in distinct chemical compositions characterized by reactive oxygen and nitrogen species. Clinically applicable exposure times (45 s, 1 min, and 1.5 min) were evaluated. For E. faecalis, 45 s of exposure resulted in reductions of 0.32 log₁₀ for PAW-Ca, 2.92 log₁₀ for PAW-Ar, and 2.73 log₁₀ for PAW-He. At 1 min, reductions increased to 0.50 log₁₀ for PAW-Ca, 3.23 log₁₀ for PAW-Ar, and > 6 log₁₀ for PAW-He. After 1.5 min, PAW-Ca achieved a 0.53 log₁₀ reduction, while PAW-Ar and PAW-He reached 2.88 log₁₀ and > 6 log₁₀ reductions, respectively. In contrast, none of the PAWs exhibited inhibitory activity against planktonic C. albicans. Cytotoxicity assays demonstrated that all PAW groups maintained ≥ 70
CuO was synthesized using various metal precursors as Cu2+ sources via a combined coprecipitation and microwave-assisted hydrothermal method, and its gas-sensing performance was systematically evaluated in relation to its structural, electronic, and morphological properties. This study systematically investigates the role of precursor chemistry as a key parameter in controlling the nucleation and growth of CuO nanostructures under identical synthesis conditions. X-ray diffraction (XRD) confirmed the formation of monoclinic CuO, and the crystallite sizes calculated using the Williamson–Hall method decreased in the order CuO-Chloride > CuO-Nitrate > CuO-Sulfate. Scanning and transmission electron microscopy (SEM and TEM) analyses revealed that all samples were composed mainly of CuO nanorods, with slight differences in thickness and dimensions. The Cu2+ oxidation state was further confirmed by X-ray photoelectron spectroscopy (XPS). The three sensors exhibited excellent NO2 detection at 200 °C, with the CuO-N sensor showing the highest response. The limit of detection (LOD) for CuO-N was 0.12 ppm, well below the safety threshold of 1 ppm, demonstrating its capability to detect low NO2 concentrations. Furthermore, the CuO-N sensor maintained stable responses over four consecutive cycles of 1 ppm NO2, indicating good operational stability without degradation of its sensing performance. The sensor produced using a metallic nitrate precursor showed the best NO2 detection response (58
