Viability study of the application of bi-block concrete sleepers as a solution for technical landfills

Transition zones, specifically embankment structures on railway tracks, are recurrently damaged by high-speed rail traffic, thus producing abrupt variations in the track vertical stiffness. The main objective of this work is to study the implementation of Construction and Demolition (C&D) wastes, specifically Bi-Block (BB) concrete sleepers, to minimize the issues related to the differences in stiffness along the area of the technical landfills, using unconventional environmental solutions. The use of BB wastes can reduce the environmental impacts caused by the construction sector. The studied solutions produce similar stiffness levels to traditional solutions. The Multicriteria Decision Support Methodology for the Relative Sustainability Assessment of Building Technologies (MARS-SC) allows concluding that the studied solutions are more sustainable than the traditional ones.This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020. Also, was cofinanced by the Interreg Atlantic Area Programme through the European Regional Development Fund under SIRMA project (Grant No. EAPA_826/2018). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 769255. The sole responsibility for the content of this publication lies with the author

In-situ laboratory X-ray diffraction applied to assess cement hydration

In-situ X-ray diffraction (XRD) is a powerful tool to assess the hydration of cementitious materials, providing time-resolved quantitative analysis with reasonable accuracy without disturbing sample. However, the lack of guidelines and well-established procedures for data collection and analysis is the limiting factor for spreading this technique. This paper discussed using in-situ laboratory XRD to assess cement hydration. The first part was dedicated to a literature review on the topic. Then, experimental strategies were discussed, and recommendations related to the data analysis routine were drawn; the advantages and limitations of this technique were also discussed. We can conclude that the critical factors for a successful analysis are the choice of an adequate experimental setup with good statistics and low measurement time, the proper consideration of different amorphous contributions in the XRD pattern, and a good data analysis routine. Independent techniques are highly recommended to support the in-situ XRD data.PID2020-114650RB-I0

Série de casos: avaliação de uma intervenção baseada em Mindfulness no estresse percebido e qualidade de vida de estudantes de medicina: Case series: evaluation of a Mindfulness-based intervention in perceived stress and quality of life of medical students

Introdução: estudantes universitários estão submetidos ao estresse resultante da sobrecarga de atividades curriculares e da constante pressão no ambiente acadêmico, o que pode gerar efeitos negativos nos estudos, no estado emocional e na saúde. O protocolo Mindfulness Based Stress Reduction (MBSR) tem demonstrado efeitos positivos para reduzir os sintomas associados ao estresse. Objetivos: avaliar os impactos do curso “Programa On-line de Qualidade de Vida Baseado em Mindfulness” na redução do estresse e na melhora da qualidade de vida em uma amostra de estudantes de medicina. Método: trata-se de uma pesquisa descritiva, exploratória e transversal, de amostragem do tipo “por conveniência”, que recrutou 33 graduandos em medicina da Univaço (Ipatinga, MG). Foram quantificados escores de qualidade de vida, estresse percebido, atenção e consciência plenas, facetas de Mindfulness e autocompaixão, antes e após participarem de um curso on-line de Mindfulness, com duração de 8 semanas. Resultados: a amostra apresentou média de idade de 22,6 anos na pré-intervenção e de 21,8 na pós-intervenção, predomínio do sexo feminino (pré-intervenção: 66,7% e pós-intervenção: 87,5%), prevalência de graduandos do 2° ano do curso na pré-intervenção (33%) e 4° ano do curso no pós-intervenção (50%) e preponderância de indivíduos solteiros (pré-intervenção: 93,9% e pós-intervenção: 100%). Houve diminuição da média de estresse percebido (36,3 para 23,6: redução de 34,9%) e das facetas de Mindfulness (122,7 para 120.5: redução de 1,8%), além de um aumento do escore total de qualidade de vida (67,6 para 78,8: ganho de 16,6%), da atenção e consciência plenas (47,5 para 60,0: ganho de 26,3%) e da autocompaixão (71,5 para 83,3: ganho de 16,3%). Conclusão: a presente pesquisa contribui para perspectivas de que as práticas de Mindfulness estão diretamente relacionadas à diminuição dos níveis de estresse e, consequentemente, a uma melhora da qualidade de vida de estudantes universitários

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