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The use of lignocellulosic material residue in cement composites is on the rise as sustainable building materials in most developing countries. Besides, this alternative is seen as a good option for new cement panels formulations for indoor applications. Thus, the current paper aims to evaluate de chemical properties of five potential lignocellulosic materials residues to be used for cement panels reinforcement: Eucalyptus, sugarcane bagasse, coconut fibre, coffee rusk, and banana pseudostem. The following physical properties of the lignocellulosic materials were evaluated: lignin, extractives, ash, and holocellulose. To evaluate the similarity of the chemical composition of the lignocellulosic materials, Hierarchical Cluster Analysis (HCA) was used identified by using Ward's method of cluster analysis. These compositions were grouped by dendrograms in which the similarity of these data was qualified. It was observed that there were statistical differences among all types of lignocellulosic materials related to the chemical composition. Coconut showed the smallest amount of extractives, and sugar cane the most significant amount. Eucalyptus and coffee husk presented the most similar chemical composition. All of the evaluated materials could be used in fibre cement production for indoor applications. [ABSTRACT FROM AUTHOR]

The use of agribusiness residual lignocellulosic fibres can be a good alternative in the development of lignocellulosic composites. The current work aimed to investigate the thermal performance of cement-based composites with lignocellulosic materials: Eucalyptus, sugarcane bagasse, coconut fibre in comparison with commercial gypsum board to be used as internal partitions of the building using infrared thermal images. Three repetitions for each kind of lignocellulosic material were made, and three commercial gypsum boards were used. In the production of the panels, the following parameters were applied: material and cement ratio, 1:2.75; water and cement ratio, 1:2.5; hydration water rate of 0.25; additive, 4% (based on cement mass). The calculations were performed for a nominal panel density of 1,200 kg m-2. The thermal analysis was performed in a chamber composed of MDP (Medium-Density Particleboard) and with an internal layer of rock wool and the heat source (thermal resistance). For the superficial temperature measurement, a FLIR E75 camera was used to capture the infrared images. When the internal temperature of the chamber stabilized at 50 °C, an infrared thermal image was collected from each side of the composite. Thermal properties were analysed: thermal conductivity, resistivity, resistance, and transmittance. Based on the results, sugar cane cement composites were characterized by higher values of thermal conductivity. Related to thermal resistivity, thermal resistance, and thermal transmittance, only the coconut panel presented similar behaviour to the commercial gypsum board. Thus, cement composite using coconut can be a potential alternative that might solve energy and environmental concerns simultaneously. [ABSTRACT FROM AUTHOR]

The use of lignocellulosic material residue in cement composites can be considered as a good option because they allow good thermal behaviour. This paper aimed to compare three kinds of cement panels reinforced with different lignocellulosic materials (Coffee husk, Coconut shell, and Banana pseudostem) based on their thermal properties. To produce each panel, the methodology suggested by Souza (1994) was used. Six replicates of each lignocellulosic panel with dimensions of 7.0×7.5 were evaluated. The thermal analysis was performed in a chamber composed of MDP (medium density particleboard). The chamber contained the heat source (incandescent lamp) connected to a thermostat that maintained the temperature at 48.0 °C. The porosity and thickness of the panels and the thermal behaviour of each sample panel (thermal conductivity, resistivity, resistance, and transmittance) and the difference in temperature of both sides of the panel were evaluated. The temperature difference to stabilization was obtained after a sampling time of 200 minutes, with 1,000 readings of 12 s each. Although all the panels were submitted under the same temperature, the inner and external superficial temperatures of the coffee husk panels reached smaller values. Besides, coconut and banana pseudostem panels presented the best results of thermal transmittance and thermal resistance. Thus, coconut shell panels present the best thermal performance, which means that this panel might be an attractive alternative building material, in terms of heat insulation for indoor applications. [ABSTRACT FROM AUTHOR]

Aim: To assess the association between probable sleep bruxism (PSB) and other occlusal characteristics in children and teenagers with Cerebral Palsy (CP)., Study Design: A cross-sectional study was carried out with 148 participants (74 with CP and 74 without special needs) aged between 2 and 14 years old. Participants underwent an oral clinical examination to evaluate the occlusal characteristics. Parents/caregivers filled out a questionnaire with information related to the typical sounds of PSB, sociodemographic factors and the presence of harmful oral habits in the study participants. Data analysis was carried out, using Chi-square or Fisher's exact test and Odds Ratio (p<0.05)., Results: PSB and malocclusion (68.9% and 95.9%, respectively) were more prevalent in participants with CP than in participants without CP. The association between PSB and the presence of a wear facet was statistically significant (p < 0.001) in participants with CP. In this group, 64.8% of participants with PSB presented tooth wear., Conclusion: Presence of dental wear facets was significantly associated with PSB in individuals with cerebral palsy.

Among members of the Fabaceae family, native to the Brazilian Caatinga, the species Poincianella pyramidalis and P. bracteosa exhibit particular potential as forage for cattle, sheep and goats. With the aim of establishing genetic relationships within Poincianella, random amplified polymorphic DNA analysis was performed on eight accessions of P. pyramidalis and two accessions of P. bracteosa, originating from the semiarid zone of the state of Piauí, northeastern Brazil, and present in the germplasm bank of Embrapa Meio Norte (Teresina, Piauí, Brazil). Amplification reactions using 11 selected arbitrary sequence primers generated 167 fragments with an overall polymorphism of 70.38%. Five monomorphic loci were generated exclusively in P. pyramidalis accessions, while three unique monomorphic loci were associated with P. bracteosa, and these represented potential species-specific markers. The similarity coefficients between Poincianella accessions were low (mean value 0.59) but with a wide variation (range 0.443 to 0.748). The similarity matrix and the dendrogram constructed using the unweighted pair group method allowed the separation of Poincianella accessions into two major clusters represented by the two distinct species, while the accessions of P. pyramidalis could be separated further into three subgroups. The high level of genetic diversity detected in the genus Poincianella could be used in future breeding programs to produce enhanced cultivars, although the variability could be better exploited if more specimens were collected from other locations within the semiarid region of northeastern Brazil.

Pityrocarpa moniliformis (Benth.) Luckow and Jobson, commonly known as angico-de-bezerro, is a forage legume that occurs naturally in the Caatinga of northeastern Brazil. This fast growing, vigorous, melliferous tree is well adapted to arid terrains and its branches and leaves possess high nutritional value. However, the scarcity of information regarding genetic variability within the species limits its possible exploitation as an animal forage. The aim of the study was to evaluate the genetic similarities of ten accessions of P. moniliformis available in the active germplasm collection of Embrapa Meio-Norte, using the RAPD markers to select those most suitable for cultivation and/or plant breeding. Polymerase chain reaction using ten selected RAPD primers generated 110 amplified loci, 106 (96.4%) of which were polymorphic. Primers A10 and M06 produced the largest number of polymorphic loci (18 and 13 bands, respectively), while primers B18 and K15 generated the smallest number (7 bands each). The dendrogram, constructed using the Jaccard coefficients and considering a cut-off point of 0.41 allowed the separation of the ten accessions into four genotypic groups. The highest genetic similarity coefficient (0.56) was observed between group I accessions BGFAB6 and BGFAB9 and BGFAB 7 and BGFAB 8, while the lowest coefficient (0.11) was observed between accessions BGFAB3 (group IV) and BGFAB10 (group III). The results revealed that genetic variability is present in the accessions of P. moniliformis.