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Light is essential for tree growth and development, yet some species are able, or prefer, to tolerate shady conditions without adversely affecting their development. This ecological preference prompts different strategies in these species, often involving a trade-off between performance and safety in terms of mechanical support, conductivity, and pest and disease protection. Studies on the ecological strategies of trees and their associated functional traits are essential to gain further insight into biodiversity and the processes that shape wood quality from the standpoint of technological properties useful to humans. This literature review showcases current links between ecological preferences and the main functional traits of tree species, with particular emphasis on wood properties.

In cardiac surgery, poststernotomy pain is a significant issue, peaking within 48 h and requiring proper analgesia for both acute relief and avoidance of chronicization. Opioids are commonly used for pain management postsurgery but pose risks such as adverse effects and dependency. Post-cardiac surgery pain can stem from various sources—somatic, visceral, and neuropathic—making opioid reliance a concern. Multimodal analgesia, which combines different medications and regional anesthesia techniques, is increasingly recommended to decrease opioid use and its related problems. Strategies include acetaminophen, gabapentinoids, NMDA antagonists, alpha-2 agonists, intravenous lidocaine, anti-inflammatory drugs, and regional anesthesia. These approaches can enhance pain control, reduce opioid reliance, and improve cardiac surgery outcomes. The ERAS® Cardiac Society strongly advocates for an opioid-sparing multimodal approach to improve patient recovery by reducing complications and increasing patient satisfaction. This review aims to consolidate current evidence to assist healthcare providers in customizing pain management for patients post-cardiac surgery, emphasizing reduced opioid use and optimizing the recovery process.

Os modelos recentes de Neural Machine Translation (NMT) podem ser aplicados a idiomas e domínios de poucos recursos sem limitações. Alguns trabalhos investigam se novas técnicas de NMT também podem ser generalizadas para diferentes recursos no que diz respeito à disponibilidade de dados e recursos computacionais. Nesse contexto, o objetivo geral deste estudo foi explorar métodos modernos de NMT e analisar a sua potencial aplicabilidade em contextos de poucos recursos, como é o caso das línguas de sinais. Para uma melhor avaliação, foram adaptados e utilizados alguns modelos promissores identificados no componente de tradução automática da Suíte VLibras e os resultados obtidos foram comparados com aqueles atualmente fornecidos pela atual arquitetura LightConv, sendo utilizado o mesmo corpus bilíngue Português-LIBRAS de treinamento e validação com mais de 70.000 sentenças geradas por linguístas, um dos maiores desse tipo disponíveis no mundo. Os resultados indicam que a adoção de uma das duas arquiteturas de melhor desempenho (Basic Transformer ou ByT5) ajudaria a melhorar a precisão e a qualidade da tradução da Suite VLibras, com um aumento percentual de até 12,73% considerando a métrica BLEU.

Abstract This manuscript proposes a robust excitation control strategy for synchronous generators using backstepping theory and an artificial neural network with a radial basis function to improve power system performance during disturbances and parametric uncertainties. The artificial neural network is used to estimate unmeasurable quantities and unknown internal parameters of a recursive backstepping control. Lyapunov theory is used to carry out the stability analysis and to deduce the online adaptation laws of artificial neural network parameters (weights, centres and widths). To validate the performance of this approach, simulations are performed on an IEEE 9 bus multi‐machine power system. Different test results, compared with those of an existing non‐linear adaptive controller, confirm the high robustness of the proposed method against disturbances and uncertainties.

IntroductionKousseri in the Far North Region of Cameroon has long been known as an endemic focus of visceral leishmaniasis (VL), although the study on sand flies in this focus is scarce. The present study investigates the spatial distribution, seasonality, and ecological aspects of sand flies from Kousseri. This study is based on the need to optimize the effectiveness of leishmaniasis control programs in the northern part of the country. MethodsSand flies were sampled monthly over 12 months in five selected sites using CDC light traps. Only captured females were morphologically identified at species level based on valid keys. Results and discussionOverall, 4,214 sand fly specimens were collected during 360 trapping nights. The male/female sex ratio slightly favored females (1:1.04). The eudominant Sergentomyia antennata followed by both dominant Sergentomyia schwetzi and Sergentomyia squamipleuris were the most common and abundant species, accounting for 76.1% of the collection. Phlebotomus duboscqi, the confirmed vector of cutaneous leishmaniasis (CL) in West African foci, although rare in the collection, was found in four of the five surveyed sites. This sand fly species with Se. schwetzi abounded in peri-urban areas and, respectively, in animal shed and in uninhabited house biotopes, while Se. antennata and Se. squamipleuris prevailed in rural areas and, respectively, in animal shelter biotopes and outside dwellings. All caught sand fly species except Se. schwetzi, Sergentomyia clydei, Sergentomyia inermis, and Sergentomyia adleri prevailed during the dry season. The highest Shannon–Wiener index of sand flies due to the maximal richness and evenness was found in the urban area, in outdoor biotopes, and during the rainy season (H′ = 1.68, 1.80, and 1.74, respectively). These data provide evidence that less urbanized areas, animal shelters around the compounds, and the absence of precipitation (dry season) favored the dispersion of abundant sand fly species in Kousseri. Based on previous reports on Leishmania transmission, a surveillance plan is required to prevent an outbreak of VL or an establishment of CL or canine leishmaniasis (CnL) in this focus. Further research identifying the blood meal source and the Leishmania parasites in these insects is critical for providing insightful data to fight leishmaniasis in Northern Cameroon.

This study evaluated consumers’ perceptions of beverages obtained from the intervarietal hybrids of Coffea canephora, Conilon and Robusta, produced in the Western Amazon, through a home-use test with 127 participants. An acceptance test and a Check-All-That-Apply procedure were applied. Two clones, BRS 2314 and BRS 2357, were studied (both in natural and fermented versions) and their roasted coffee composition was also evaluated. All beverages were described as having a mild aroma, roasted flavor, and slightly sour taste; consumers noticed both the effect of the fermentation process and genetics. Natural coffees had greater sensory acceptance than fermented ones. Natural coffees were most associated with a slightly bitter taste, and were well accepted by almost half of the participants, mainly women. Fermented coffees were both associated with fermented flavor, but also presented specific characteristics. BRS 2314F was most associated with a fruity flavor and slightly bitter taste and was well accepted by younger consumers with higher levels of education. BRS 2357F was most associated with tobacco flavor and bitter taste and was well accepted by older consumers with a lower education level and a higher coffee consumption frequency. The positive acceptance of C. canephora intervarietal hybrid beverages allowed us to confirm its material market potential.

This work deals with the determination of some properties of laminated veneer lumber (LVL) made from tropical hardwoods, specifically focusing on Cameroonian woods. The LVL samples are manufactured using veneer from three tropical wood species: Ayous, Ilomba, and Bete. Two types of adhesives are used: a neoprene contact adhesive (Magpow) and a white vinyl adhesive (Nemo). The specimens have undergone multiple drying cycles, and hundreds of samples from each species have been selected with dimensions of 1 cm × 1 cm × 1 cm. These samples are then machined according to the specific wood grain of each species. The experiments conducted aim to determine properties such as moisture content, densities, volume swelling, shrinkage coefficients, and the hygroscopic point of equilibrium of the samples. Swelling and shrinkage measurements allow for the visualization of sample dimensions in relation to humidity levels, and the hysteresis of the adsorption phenomenon of the LVL is also obtained. The results show that regardless of the type of adhesive or veneer used, LVLs are denser than the wood they are made from. For each type of LVL, the ratio between the mass of a sample saturated in water and the mass of the dried sample remains constant. The rule of mixture is investigated, and the density properties of materials and the vacuum rates of LVL samples are compared with experimental data.

Stone Age sites are well known to often contain many lithic flint blades and flakes, which may provide important information about early European Stone Age cultures and their environment. Understanding the mechanical behaviour of lithic flint blades represents an important problem for scientists in general and archaeologists in particular. In this study, the structural behaviour of lithic flint blades is studied. Ten specimens with different geometric shapes (tilted, curved, with bumping surfaces) were studied and tested. Their natural frequencies, damping ratios, and mode shapes (that is how the specimen deforms under any external excitation) are estimated using two models: an analytical model that accounts for the specimen's curvature and a 3D Finite Element (FE) method. Advanced experimental methods, including ultrasound techniques, were used to measure the mechanical properties of the specimens. The experimental set-up was built around a laser vibrometer that measured the specimen's displacement. The model predictions were compared with the experimental data to validate their effectiveness. A good agreement is observed between the models and the real data. It is particularly observed that despite their complicated geometries, the specimens still follow a structured pattern in their dynamic response. The presented study supports the use of acoustic methods as an effective tool to characterize and detect submerged prehistoric materials. This work contributes to the dynamic characterization of submerged Stone Age materials.

As electric bikes continue to grow in popularity, it is important to ensure that they are equipped with well-designed components. One such component is the rear swing arm (RSA). This study deals with the design and structural analysis of an RSA used for electric bikes. This RSA is composed of two swing arms (one on each side of the bikes), a yoke, a suspension block, and bolts or screws. First, an analytical approach was developed to calculate the initial values for the width and shape of the swing arm. Next, experimental data were used to analyze the response of the RSA and determine the final profile for the swing arms and yoke structure. Finally, the finite element approach was implemented to assess the stress, displacement, and fatigue responses of the RSA when subjected to realistic excitations and conditions. The initial results depicted the following characteristics for the RSA: C-channel profile, 43 mm height, and 2 mm wall thickness. These results implied that the maximum shear force would occur in a region representing approximately 15.5% of the total length of the RSA. Further analysis and calculations showed that this region would decrease to approximately 2.85% of the total length of the RSA. For the final design, the mechanical performance of the RSA was observed to remain acceptable despite the relatively high Von Mises stress values around these singularities. This study assumed the use of 7075 T651 aluminum alloy as the primary material for the RSA.

Abstract Preventive chemotherapy (PC) that remains the main control strategy recommended by the World Health Organization to achieve the elimination of soil-transmitted helminth (STH) infections as a public health problem must be strengthened by identifying the remaining transmission hot-spots for the deployment of appropriate control measures. This study was designed to assess the prevalence and infections intensities of soil-transmitted helminths and perform micro scale mapping in order to identify transmission hot-spots for targeted control operations. Stool samples were collected from 1775 children in ten primary schools of eight sub-districts of Makenene in Cameroon. Kato Katz technique was used to process and examine stool samples to detect the eggs of soil-transmitted nematodes. The prevalence of soil-transmitted helminth species as well as the infection intensities was compared. Data visualizations in forms of maps were made using Quantum geographic information system (QGIS) software. The overall prevalence of soil-transmitted helminth infections was 4.8% with a 95% confidence interval (CI) of 3.8–5.9%: 3.0% (95% CI 2.2–3.9) for Ascaris lumbricoides, 1.4% (95% CI 0.9–2.0) for Trichuris trichiura and 0.8% (95% CI 0.5–1.4) for hookworms. The prevalence of soil-transmitted helminth species differ significantly between schools and sub-districts. The intensity of infections was light (2.4%, 1.1% and 0.8%), moderate (0.4%, 0.1% and 0.1%) and heavy (0.2%, 0.2% and 0%) for A. lumbricoides, T. trichiura and hookworm respectively. The mean intensity of infections was 7255 EPG for A. lumbricoides, 2900 EPG for T. trichiura and 298 EPG for hookworm. Between schools, significant difference was recorded in the means of infection intensities of T. Trichiura and hookworms but not for A. lumbricoides. This difference was also significant for T. Trichiura when comparison were between sex. No significant difference were recorded when the comparison were between age. Fine mapping revealed that children harbouring heavy infections were clustered in the same sub-districts; highlighting the presence of high endemicity sub-districts and hot-spots for the transmission of different soil-transmitted helminth species. This study showed a diversity in the prevalence and transmission of different soil-transmitted helminth species. It also hightlighted the need for micro scale mapping to enable the localisation of high endemicity sub-districts and transmission hot-spot sites where targeted control operations must be deployed to achieve STH elimination.

Abstract Background Dengue (DENV), chikungunya (CHIKV) and Zika virus (ZIKV), are mosquito-borne viruses of medical importance in most tropical and subtropical regions. Vector control, primarily through insecticides, remains the primary method to prevent their transmission. Here, we evaluated insecticide resistance profiles and identified important underlying resistance mechanisms in populations of Aedes aegypti and Ae. albopictus from six different regions in Cameroon to pesticides commonly used during military and civilian public health vector control operations. Methods Aedes mosquitoes were sampled as larvae or pupae between August 2020 and July 2021 in six locations across Cameroon and reared until the next generation, G1. Ae. aegypti and Ae. albopictus adults from G1 were tested following World Health Organization (WHO) recommendations and Ae. aegypti G0 adults screened with real time melting curve qPCR analyses to genotype the F1534C, V1016I and V410L Aedes kdr mutations. Piperonyl butoxide (PBO) assays and real time qPCR were carried out from some cytochrome p450 genes known to be involved in metabolic resistance. Statistical analyses were performed using Chi-square test and generalized linear models. Results Loss of susceptibility was observed to all insecticides tested. Mortality rates from tests with 0.25% permethrin varied from 24.27 to 85.89% in Ae. aegypti and from 17.35% to 68.08% in Ae. albopictus. Mortality rates for 0.03% deltamethrin were between 23.30% and 88.20% in Ae. aegypti and between 69.47 and 84.11% in Ae. albopictus. We found a moderate level of resistance against bendiocarb, with mortality rates ranging from 69.31% to 90.26% in Ae. aegypti and from 86.75 to 98.95% in Ae. albopictus. With PBO pre-exposure, we found partial or fully restored susceptibility to pyrethroids and bendiocarb. The genes Cyp9M6F88/87 and Cyp9J10 were overexpressed in Ae. aegypti populations from Douala sites resistant to permethrin and deltamethrin. Cyp6P12 was highly expressed in alphacypermethrin and permethrin resistant Ae. albopictus samples. F1534C and V1016I mutations were detected in A. aegypti mosquitoes and for the first time V410L was reported in Cameroon. Conclusions This study revealed that Ae. aegypti and Ae. albopictus are resistant to multiple insecticide classes with multiple resistance mechanisms implicated. These findings could guide insecticide use to control arbovirus vectors in Cameroon.

Due to their high strength and favourable mechanical behaviour, metals are used in a variety of applications within the automotive industry, including drive shafts. However, the use of metallic drive shafts in the automotive sector presents some disadvantages such as high inertial masses. This work investigates the mechanical benefits of using Carbon Fibre Reinforced Polymers (CFRP) for manufacturing drive shafts. A Formula Student car was used as a model for the present work design for the drive shaft. Drive shafts made of Steel AISI 4340, Aluminium, and CFRP are investigated when subjected to mechanical excitations. Simulation includes the use of Comsol Multiphysics software. The CFRP drive shaft was modelled using the layered material feature. Various stacking sequences are tested. Results show that [90°/0°/-45°/+45°] sequence presents the best mechanical behaviour. Analytical and numerical calculations for the natural frequencies are performed and compared. CFRP drive shaft is observed to give the highest fundamental natural frequency when compared to the metallic counterparts. Fatigue analysis are also studied and revealed that the drive shafts can sustain the applied load for its expected fatigue life, with the CFRP drive shaft having the highest fatigue usage factor. Critical buckling analysis showed that the drive shaft made of steel has the highest critical buckling torque. However, drive shafts made of carbon fibre reinforced polymer was found to be 40.7% lighter than the aluminium tube and 79.6% lighter than the steel tube.

The bank run phenomenon, mostly due to rumor spread about the financial health of given financial institutions, is prejudicious to the stability of financial systems. In this paper, by using the epidemiological approach, we propose a nonlinear model for describing the impact of rumor on the banking crisis spread. We establish conditions under which the crisis dies out or remains permanent. We also solve an optimal control problem focusing on the minimization, at the lowest cost, of the number of stressed banks, as well as the number of banks undergoing the restructuring process. Numerical simulations are performed to illustrate theoretical results obtained.

This work aimed to study the initial stress to cracking of Cameroonian tropical woods. The forests of the Cameroonian part of the Congo Basin, abound in species highly sought after for structural applications. However, very little information is available on the Mode I cracking of these wood species. Specimens of sound wood from dabema (Piptadeniastrum africanum), padouk (Pterocarpus soyauxii Taub) and bilinga (Diderrichii nauclea) were produced. These specimens were subjected to three-point bending tests. Physical (density and moisture content), mechanical (modulus of elasticity, bending stress at break) and energetic (restitution rate and stress intensity factor) properties were determined. The results gave a restitution rate of 581 J/m² for dabema, 520 J/m² for bilinga and 202 J/m² for padouk, and a stress intensity factor of 0.98 MPa*m1/2 for dabema, 1.28 MPa*m1/2 for bilinga and 1.0 MPa*m1/2 for padouk. It can be seen that dabema and bilinga are more resistant to crack propagation than padouk. On the other hand, bilinga and padouk absorb much more of the energy that causes micro cracks than dabema. [ABSTRACT FROM AUTHOR]

PurposeThe management of household wastes has been a real challenge for the capital city of Cameroon for some years now. In order to adopt ecological and sustainable strategies for better management of organic fraction of solid wastes, the present work was aimed to propose a sustainable alternative for the recycling of household organic waste through a vermicomposting process. Method A vermicomposting of household organic waste was carried out during 46 days, preceded by 23 days of pre-composting. Then, three treatments were established by mixing epigeic earthworms with different proportion of pre-composted waste. Maturation parameters such as pH, electrical conductivity (EC), C/N ratio, ammonium (N-NH4+) and total organic matter (TOM) were monitored about four weeks. The agronomic quality of the vermicompost was also determined at the end. Results During pre-composting, the temperature reached a maximum of 54.3±5.4°C suitable for the elimination of potential pathogen. The pH varied between 9.44 and 8.53 leading towards neutrality at the end of the vermicomposting process. The obtained mean values of C/N ratio and the TOM were respectively 11.04-11.68 and 25.82-27.19% in line with the AFNOR (NFU 44-051) guideline. The obtained vermicompost revealed high levels of nutrients such as N, P, K, Ca and Mg. The phytotoxicity test on lettuce showed germination rates above 50%, revealing the non-toxic nature of the vermicompost produced. Conclusion The vermicompost were rich in nutrients and exhibited the non-phytotoxicity. Thus, vermicomposting can be applied in the context of Cameroon to transform organic waste into organic fertiliser suitable for sustainable agriculture.

Summary: Gorillas reside in sympatry with chimpanzees over the majority of their range. Compiling all known reports of overlap between apes and augmenting these with observations made over twenty years in the Ndoki Forest, we examine the potential predation-related, foraging, and social contexts of interspecific associations between gorillas and chimpanzees. We reveal a greater diversity of interactions than previously recognized, which range from play to lethal aggression. Furthermore, there are indications that interactions between ape species may serve multiple functions. Interactions between gorillas and chimpanzees were most common during foraging activities, but they also overlapped in several other contexts. From a social perspective, we provide evidence of consistent relationships between particular chimpanzee-gorilla dyads. In addition to providing new insights into extant primate community dynamics, the diversity of interactions between apes points to an entirely new field of study in early human origins as early hominins also likely had opportunities to associate.

BackgroundSchistosomiasis control relies mainly on mass drug administration of Praziquantel (PZQ) to school aged children (SAC). Although precision mapping has recently guided decision making, the sub-districts and the epidemiological differences existing between bio-ecological settings in which infected children come from were not taken into consideration. This study was designed to fill this gap by using POC-CCA and KK to comparatively determine the prevalence and infection intensities of Schistosoma mansoni (S. mansoni) and to perform fine-scale mapping of S. mansoni infections and its infection intensities with the overarching goal of identifying sub-districts presenting high transmission risk where control operations must be boosted to achieve schistosomiasis elimination.MethodologyDuring a cross- sectional study conducted in Makenene, 1773 stool and 2253 urine samples were collected from SAC of ten primary schools. S. mansoni infections were identified using the point of care circulating cathodic antigen (POC-CCA) and Kato-Katz (KK) test respectively on urine and stool samples. Geographical coordinates of houses of infected SAC were recorded using a global position system device. Schistosome infections and infection intensities were map using QGIS software.ResultsThe prevalence of S. mansoni inferred from POC-CCA and KK were 51.3% and 7.3% respectively. Most infected SAC and those bearing heavy infections intensities were clustered in sub-districts of Baloua, Mock-sud and Carrière. Houses with heavily-infected SAC were close to risky biotopes.ConclusionThis study confirms the low sensitivity of KK test compared to POC-CCA to accurately identify children with schistosome infection and bearing different schistosome burden. Fine-scale mapping of schistosome infections and infection intensities enabled to identify high transmission sub-districts where control measures must be boosted to reach schistosomiasis elimination.

Light is essential for tree growth and development, yet some species are able, or prefer, to tolerate shady conditions without adversely affecting their development. This ecological preference prompts different strategies in these species, often involving a trade-off between performance and safety in terms of mechanical support, conductivity, and pest and disease protection. Studies on the ecological strategies of trees and their associated functional traits are essential to gain further insight into biodiversity and the processes that shape wood quality from the standpoint of technological properties useful to humans. This literature review showcases current links between ecological preferences and the main functional traits of tree species, with particular emphasis on wood properties. [ABSTRACT FROM AUTHOR]

In cardiac surgery, poststernotomy pain is a significant issue, peaking within 48 h and requiring proper analgesia for both acute relief and avoidance of chronicization. Opioids are commonly used for pain management postsurgery but pose risks such as adverse effects and dependency. Post-cardiac surgery pain can stem from various sources—somatic, visceral, and neuropathic—making opioid reliance a concern. Multimodal analgesia, which combines different medications and regional anesthesia techniques, is increasingly recommended to decrease opioid use and its related problems. Strategies include acetaminophen, gabapentinoids, NMDA antagonists, alpha-2 agonists, intravenous lidocaine, anti-inflammatory drugs, and regional anesthesia. These approaches can enhance pain control, reduce opioid reliance, and improve cardiac surgery outcomes. The ERAS® Cardiac Society strongly advocates for an opioid-sparing multimodal approach to improve patient recovery by reducing complications and increasing patient satisfaction. This review aims to consolidate current evidence to assist healthcare providers in customizing pain management for patients post-cardiac surgery, emphasizing reduced opioid use and optimizing the recovery process. [ABSTRACT FROM AUTHOR]

This study evaluated consumers' perceptions of beverages obtained from the intervarietal hybrids of Coffea canephora, Conilon and Robusta, produced in the Western Amazon, through a home-use test with 127 participants. An acceptance test and a Check-All-That-Apply procedure were applied. Two clones, BRS 2314 and BRS 2357, were studied (both in natural and fermented versions) and their roasted coffee composition was also evaluated. All beverages were described as having a mild aroma, roasted flavor, and slightly sour taste; consumers noticed both the effect of the fermentation process and genetics. Natural coffees had greater sensory acceptance than fermented ones. Natural coffees were most associated with a slightly bitter taste, and were well accepted by almost half of the participants, mainly women. Fermented coffees were both associated with fermented flavor, but also presented specific characteristics. BRS 2314F was most associated with a fruity flavor and slightly bitter taste and was well accepted by younger consumers with higher levels of education. BRS 2357F was most associated with tobacco flavor and bitter taste and was well accepted by older consumers with a lower education level and a higher coffee consumption frequency. The positive acceptance of C. canephora intervarietal hybrid beverages allowed us to confirm its material market potential. [ABSTRACT FROM AUTHOR]