Experimental evaluation of the employment of a laminated composite material with sisal fibres as reinforcement in timber beams.

Abstract Timber is the oldest construction materials in the world, have been widely used in structures in addition to having a high longevity, if treated properly (maintenance). If this does not occur, the wood deteriorates due to the action of insects, fungi and other aggressive agents. There are several materials and techniques used to reinforce the damaged parts. This paper presents an experimental study ofEucalyptus grandis and Pinus elliiottiitimber bea ms rein forced with sisal fibres laminated composite materials. The co mposite material and the wood were prepared for testing. In order to simulate the defect, some parts were cracked. The study was to determine the maximu m load (rupture) applied on the timberin the conditions: without defect, with defect and without composite and with defect and with composite, aiming to verify the efficiency of the laminate as reinforcement in the wooden beams. The experimental results indicate the possible use of the laminated composite as reinforcement, presenting considerable increase in the maximu m strength supported by the timber when compared to unreinforced cracked condition, being more efficient for the Pinus elliiottii species

Geometric effects of sustainable auxetic structures integrating the particle swarm optimization and finite element method

The development of new materials based on industrial wastes has been the focus of much research for a sustainable world. The growing demand for tyres has been every year exacerbating environmental problems due to indiscriminate disposal in the nature, making a potentially harmful waste to public health. The incorporation of rubber particles from scrap tyres into polymeric composites has achieved high toughness and moderate mechanical properties. This work investigates the geometric effects (thickness, width and internal cell angle) of auxetic structures made of recycled rubber composites based on experimental and numerical data. The response surface models integrated with the swarm intelligence and finite element analysis were proposed in order to obtain a range of solutions that provides useful information to the user during the selection of geometric parameters for reentrant cells. The results revealed the cell thickness ranges from 39-40 mm and 5.98-6 mm, and the cell angle range from -0.01 to -0.06º maximize the ultimate strength. The same parameters were able to optimize the modulus of elasticity of rubber auxetic structures, excepting for the angle factor which must be set between -30º and 27.7º. The optimal Poisson's ratio was found when the cell angle ranged from -30º to -28.5º, cell width ranged from 5-5.6 mm and 2 mm in thickness

Aspectos anatomopatológicos do paciente portador de Pneumonia: Anatomopathological aspects of the patient with Pneumonia

A pneumonia condiz a uma condensação inflamatória aguda dos alvéolos e/ou infiltração tecidual intersticial pulmonar que resulta da ação de células inflamatórias em resposta a injúrias de um determinado agente microbiano. A patologia conforme o local de aquisição, o padrão de comprometimento, o agente etiológico são determinantes para o quadro clínico, lesões e achados radiográficos. O seguinte artigo objetivou descrever através da revisão bibliográfica, os aspectos gerais da pneumonia com foco em abordar os aspectos anatomopatológicos desta enfermidade. Trata-se  de  um  estudo qualitativo  de  revisão  narrativa,  elaborado  para  abordar  sobre os aspectos anatomopatológicos do paciente portador de pneumonia.  É composta por uma análise ampla da literatura, e com uma metodologia rigorosa e replicável ao nível de reprodução de dados e questões quantitativas para resoluções específicas.  Conforme as informações disponíveis na literatura, elucida-se que os pulmões contam com um aparato de mecanismos de defesa. Mas, mediante injúrias e agentes agressores geram um desequilíbrios e posteriormente originam condições que favorecem doenças respiratórias. A pneumonia possui vários agentes etiológicos, e de acordo com este, distintos padrões de acometimento pulmonar e achados radiográficos irão se manifestar

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio