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Particleboards have gained attention in the global market. Understanding their physical-mechanical behavior in the current technological context is essential due to adhesive polymerization, which depends on variables such as pressing time and temperature. Today, the use of nanoparticles has become a plausible option for improving the properties of polymers used in wood-based composites. This study evaluates the influences of the addition of non-commercial 0.5% aluminum oxide (Al 2 O 3 ) and aluminum oxide copper (CuO) nanoparticles using a greener route with a lower environmental impact obtaining a urea-formaldehyde (UF)-based polymeric adhesive to manufacture particle composites of Eucalyptus urophylla var. grandis wood. Regarding characterizations, the resin properties analyzed were viscosity, gel time, and pH, as well as panel properties, including density, moisture content, thickness swelling, modulus of elasticity, modulus of rupture, and thermal conductivity. The results were compared with scientific publications and standards. The addition of nanoparticles interfered with viscosity, and all treatments indicated a basic pH. It was not possible to determine the gel time after 10 min. Nanoparticles added to the polymers in the internal layer did not cause an improvement in the swelling properties in terms of thickness, with no significant statistical difference for density and moisture content. The increase from 150 °C to 180 °C may have caused an improvement in all physical-mechanical properties, indicating that the higher temperature positively influenced the polymerization of the formaldehyde-based adhesive. Therefore, the additions of both nanoparticles (0.5% in each condition) led to a limitation in the material influence with respect to physical-mechanical performance.

Using Kraft lignin, bio-based adhesives have been increasingly studied to replace those petrochemical-based solutions, due to low cost, easy availability and the potential for biodegradability of this biomaterial. In this study, lignin-based phenol-formaldehyde (LPF) resins were synthesized using commercial Eucalypt Kraft Lignin (EKL), purified at 95%, as a phenol substitute in different proportions of 10%, 20%, 30% and 50%. The properties of bio-based phenol formaldehyde (BPF) synthesized resin were compared with phenol-formaldehyde resin (PF) used for control sampling. The results indicated that viscosity, gel time and solid contents increased with the addition of pure EKL. The shear strength test of glue line was studied according to American Society for Testing and Materials (ASTM), and BPF-based results were superior to samples bonded with the PF as a control sample, being suitable for structural purposes. Changes in the curing behavior of different resins were analyzed by Differential Scanning Calorimetry (DSC), and sample comparison indicated that the curing of the LPF resin occurred at lower temperatures than the PF. The addition of EKL in PF reduced its thermal stability compared to traditional resin formulation, resulting in a lower decomposition temperature and a smaller amount of carbonaceous residues.

The Zika virus was responsible for an outbreak between 2015 and 2016 in Brazil: an alarming public health problem of international relevance. The Congenital Zika Syndrome (CZS) is often associated with manifestations that are responsible for cognitive and motor development delays and behavioral disorders. Thus, we aimed to characterize the clinical-epidemiological and familial context of those children and to identify factors associated with the risk of behavioral disorders using the Survey of Well-Being of Young Children questionnaire (SWYC). In total, 52 children diagnosed with CZS were evaluated. Logistic regressions were employed to assess predictive variables for behavioral alteration. Eighteen (35%) of the children presented a risk of behavioral alteration. Children born normocephalic were 36-fold more likely to present behavioral alteration (95% CI: 3.82 to 337.92, p = 0.002). Children with hearing and visual impairments showed reduced risks. In total, 35% percent of families reported food insecurity and 21% were at risk for maternal depression. Our findings suggest better social interactions and conditions to externalize reactions for children with CZS born normocephalic. The continuous assessment of these children and families may identify conditions associated with behavioral alteration and psychosocial vulnerabilities that help in decision-making, therefore optimizing patient-family interactions.

The electromechanical impedance (EMI) technique is considered to be one of the most promising methods for developing structural health monitoring (SHM) systems. This technique is simple to implement and uses small and inexpensive piezoelectric sensors. However, practical problems have hindered its application to real-world structures, and temperature effects have been cited in the literature as critical problems. In this paper, we present an experimental study of the effect of temperature on the electrical impedance of the piezoelectric sensors used in the EMI technique. We used 5H PZT (lead zirconate titanate) ceramic sensors, which are commonly used in the EMI technique. The experimental results showed that the temperature effects were strongly frequency-dependent, which may motivate future research in the SHM field.