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Background: Sub-Saharan African countries have a high burden of viral hepatitis and poor access to screening and care. The aim of this study was to evaluate the feasibility and acceptability of using the plasma separation card (PSC) for viral hepatitis B and C screening among people living with HIV (PLHIV) in Cameroon and Uganda. Methods: This is a cross-sectional study carried out between 05/2021 and 03/2023 including 192 PLHIV in Cameroon (n = 104) and Uganda (n = 88). Basic sociodemographic variables and whole blood samples were collected. Adequate filling with blood of PSCs was used to determine feasibility together with participant responses to questions on acceptability. A logistic regression model was carried out to assess the relationship between PSC acceptability and factors of interest. Results: 70% of participants reported PSC as an acceptable viral hepatitis screening tool, and it was significantly more accepted in Uganda than Cameroon (100% vs. 43.2%, p < 0.001). Similarly, 75% of PSCs had at least one spot sample filled and were viable for analysis, 99% were correctly filled in Uganda and 53.4% in Cameroon. Reported ease of method performance (aOR: 24.77 95% CI 2.97-206.42, p = 0.003) and reduced collection time (aOR: 3.73 95% CI 1.26–11.04, p = 0.017) were associated with greater odds of PSC acceptance. HBsAg + and anti-HCV + prevalence were 11.1% and 1.0%, respectively. Conclusions: In spite of country differences, overall, the PSC was reported as a feasible and acceptable viral hepatitis testing method. Acceptability and feasibility of the method must be explored in heterogeneous target communities and qualitative research to better understand country-specific barriers and facilitators should be carried out. [ABSTRACT FROM AUTHOR]

Wood is an interesting material especially when used outdoors where it is exposed to weathering and degradation. Heat treatment of wood has proved to be an ecological way for outdoor use which is particularly useful in the case of less durable wood, it is also a non-biocidal alternative to the classical techniques of prolonging the natural durability of wood. Heat treatment decreases hygroscopicity which guarantees a lower sensitivity of the wood material towards environmental variations both of moisture and temperature. In this context, it is essential to check the behavior of heat-treated wood over time. The aim of this work was to verify the effects of the natural aging process on some physical properties of heat-treated Ayous (Triplochiton scleroxylon K. Schum) wood. The wood of this species becomes increasingly attractive on the international market due to the rapid growth of the trees and easy wood processing. The material used in the study comes from certified forests for sustainable management that grow in Cameroon. The Ayous planks were donated by Vasto Legno, the company also submitted the planks to heat treatment at an industrial plant. The heat treatment was carried out at 215°C for three hours with a slight initial vacuum. The planks, treated and untreated, were exposed outdoor conditions for one year. A statistical analysis has shown that the density of heat-treated aged wood remains significantly lower than the untreated aged wood. Compared to environmental humidity, the heat-treated wood reaches a consistently lower moisture content than the untreated wood that indicates an appreciable dimensional stability of the material. Even after 12 months a lower ability to absorb moisture than the untreated wood was retained. The anti-shrinkage efficiency (ASE) value supports this improvement. However, the ASE value was found to be below 75%-threshold, which is indicated as the minimum effective threshold. Colour is an important factor which affects the aesthetics of wooden products. Heat treatment induced darkening, measured by the chromatic coordinates' values and was clearly visible even to the naked eye on the naturally light-yellow colour of the ayous. The colour variation indicates chemical modifications, and lignin degradation contributes to the darkening of wood. The natural aging process causes a colour variation as well, both in the untreated and in the treated wood. In the natural wood there was a darkening of the surface, and the plank surface acquired a greyish colour/hue. The heat-treated wood was darkened by the treatment rather than turning lighter. Natural aging of wooden surfaces leads to a slow deterioration of wooden surfaces, which cause unwanted changes. However, the process is worth investigation after longer exposure times. [ABSTRACT FROM AUTHOR]

Highlights: [•] Logging activities with selective cutting in a tropical forest were analyzed. [•] Analysis focused on logging systems, productivities and energy consumption. [•] The extraction operation by wheeled skidder and by crawler were compared. [•] For the extraction operation, skidder use is preferable to the crawler. [•] In the energy consumption, the main role was played by direct input (fossil fuels). [Copyright &y& Elsevier]

High-temperature treatment of wood is a useful method for improving certain physical characteristics, ensuring durability without biocides, and improving the performance of wood when exposed to degradation agents. This work aims to determine the effects induced by a heat treatment performed industrially on ayous wood (Triplochiton scleroxylon K. Schum) from Cameroon, through the study of the main physical and mechanical characteristics. The heat treatment at 215 °C for three hours with a slight initial vacuum determined a reduction of the mechanical characteristics (compression strength 26%, static bending 46%, Brinell hardness 32%) and some physical properties (dry density 11%, basic density 9%), while it improved the behaviour towards variations of environment moisture. The anti-shrinkage efficiency was 58.41 ± 5.86%, confirming the increase of the dimensional stability. The darkening (ΔE 34.76), clearly detectable (L* 39.69 ± 1.13; a* 10.59 ± 081; b* 18.73 ± 1.51), was supported almost equally by both the lightness parameter (L*) and the a* chromatic parameter. The data collected during the laboratory tests were then subjected to statistical analysis to verify correlations between the characteristics examined. Statistical differences were highlighted between each physical and mechanical properties of ayous wood modified or not. [ABSTRACT FROM AUTHOR]