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After forest suppression in mining areas, deterioration of stocked tropical hardwoods occurs at different rates and levels. Prioritizing logs to avoid wastage is challenging because the wide interspecific variability of wood traits makes natural resistance unpredictable. This work aimed to compare the biodeterioration of four Amazonian hardwoods from a mining stockyard to arboreal termite attacks over six weeks under laboratory conditions. The woods' chemical composition, anatomy, basic density, and crystallinity were determined. Mass loss and visual diagnosis of the specimens supported the biodegradability analyses. The species showed a wide range of mass loss after six weeks: Jacaranda copaia (pará-pará) - 15,2 %; Pseudopiptadenia suaveolens (timborana) - 0,8 %; Aegiphila integrifolia (tamanqueira) - 5,2 %; and Euxylophora paraensis (pau amarelo) - 0,5 %. Biodegradation did not stabilize over time for the lowest-density species. The crystallinity indicated the initial degradation of amorphous wood components, followed by a non-selective feeding mechanism. Gathering all species, increased extractive and lignin levels, fiber wall thickness, and basic density favored the natural wood resistance, oppositely to large vessel elements. The much lower basic density of J. copaia explains its lowest natural resistance. Wall thickness, pore diameter, and density overcame chemical composition on wood biodegradability. Low-density hardwoods stocked in mining yards are a priority for proper destinations.

Objectives: Identifying voice handicap and voice-related quality of life in patients presenting pulmonary impairment associated with COVID-19 infection, comparing pulmonary parameters between these patients and individuals in the control group, as well as correlating pulmonary parameters to self-assessment questionnaires (IDV-10 and QVV). Methods: Thirty-five (35) patients presenting pulmonary impairment with COVID-19 infection were herein selected and compared to 35 individuals who were not affected by COVID-19 infection. Two self-assessment questionnaires were applied (vocal handicap index and voice quality of life protocol). Maximum phonation time Forced Expiratory Pressure (PEF) and Forced Inspiratory Pressure (PIF) were measured and videolaryngoscopy was performed. Results: There was statistically significant difference in scores recorded in voice self-assessment questionnaires (IDV-10 and QVV), Expiratory Pressure (PEF) and Forced Inspiratory Pressure (PIF) between patients with pulmonary impairment associated with COVID-19 infection and those in the control group. Correlation between PEF/PIF and scores recorded in voice self-assessment questionnaires was also observed. Conclusion: Pulmonary impairment associated with COVID-19 infection has worsened voice handicap and voice-related quality of life in the assessed patients, as well as reduced their forced expiratory and inspiratory pressure in comparison to the control group. Level of evidence: 4.

As an alternative for the partial replacement of synthetic adhesives are the modifications that occur still during their synthesis, to improve and adhere new properties. Among the possible materials used in nanoscale, talc is a mineral material of natural origin and a promising raw material due to its low cost, lightness, natural hydrophobicity. Due to the scarcity of studies with the insertion of nanotalc in adhesives, this study aimed to produce plywood panels bonded with phenol-formaldehyde adhesive nanomodified with talc to evaluate its physical-mechanical resistance when compared to conventional synthetic adhesives. To carry out this study, three Pinus oocarpa trees with 28 years of age were used. Different concentrations of talc were used in the formulation with the phenol-formaldehyde adhesive, being the treatments 0; 0,05; 1; 1,5 and 2 % of talc (mass/mass) in relation to the adhesive, with three panels per treatment, totaling 15 panels. The pressing time was 8 minutes with temperature of 160 ºC and pressure of 1 MPa. The physical-chemical characteristics of the lignocellulosic material and of the plywood panels were determined. The quality of the adhesive produced was demonstrated by its resistance to water absorption with the insertion of up to 2 % talc to the adhesive, reducing it considerably. From 1 % talc inserted, the plywood panels had their mechanical characteristics superior to those glued with pure phenol-formaldehyde adhesive. However, as the study is innovative in nature, further research should focus on the application and quality evaluation of other talc nanomodified adhesives on different types of wood panels.

This paper was carried out aiming to evaluate the influence of the following processing variables on the properties of OSB: face to core layer ratios of 30-40-30 and 20-60-20 in relation to a single layer; phenol-formaldehyde resin content of 3, 4.5 and 6.0% and addition of 0.5 or 1.0% of wax sizing. The results showed that the boards composed of face to core layer ratios of 20-60-20, presented the better balance in static bending tests, both in the machine and cross-machine directions. The application of 4.5 and 6.0% of resin resulted in better physical and mechanical properties of the OSB. The OSB produced with Eucalyptus grandis, and 4.5 and 6.0% of phenol-formaldehyde resin were in compliance with values of the mechanical properties of the Canadian Standards CSA 0437-0 (1993).

This work had the objective to study the species effects, and the wax addition in the OSB panels properties. The final conclusion was that the studied species are homogeneous among themselves and they produce similar quality panels. The produced panels attended to the minimum specifications of the CSA 0437.0 Canadian standard.

This research was developed aiming to evaluate the potentiality of soy bean, rice flour, maize flour, oatmeal and manioc flour, as alternative extenders to wheatmeal for plywood manufaturing. Twenty one boards were produced using Eucalyptus cloeziana venner, being three boards per treatment according to the following formulation in parts per wheight: urea-formaldheyde resin 100, extender 75, water 80 and catalyst 7. The average values of shear bonding tests (dry and wet), showed that the ricemeal and oatmeal could be used as an alternative extender to the wheatmeal.