The Federal University of Western Pará (Portuguese: Universidade Federal do Oeste do Pará, UFOPA) is a public university in the state of Pará, in northern Brazil.UFOPA was founded in 1970 as Núcleo de Educação em Santarém (NES), and was renamed UFOPA in 2009. It has an annual budget of 90 million real, and has over 400 faculty and over 10,000 students..
Using nail plates to connect timber structural elements is a way to reduce costs and time during assembly, but moisture-induced backout can compromise these connections in the medium and long term. Most nail plate backout models proposed are based on a single tooth backout, and therefore, do not consider the influence of the metal plates at their bases. This study aimed to verify the effect of the plate connection on the backout. The dimensional changes, including a holistic approach to nail plate behaviour were evaluated in two treatments: S-D cycle, where wood started saturated and then dried to 0
This article introduces two matrix-variate asymmetric distributions for modeling data exhibiting skewness and latent scale variability: the matrix-variate shifted asymmetric Laplace (MVSAL) and the matrix-variate shifted generalized asymmetric Laplace (MVSGAL). Both distributions arise within the class of matrix-variate normal mean-variance mixtures, yielding a hierarchical representation that facilitates random generation and likelihood-based inference. Several structural properties are established, including closure under linear transformations and marginalization. An Expectation/Conditional Maximization (ECM) algorithm is developed for maximum likelihood estimation, and simulation results demonstrate accurate parameter recovery with improved stability as the sample size increases. An empirical application to seasonal climatic data from 100 municipalities in the state of São Paulo illustrates the practical use of the MVSGAL model in a multivariate matrix setting, capturing temporal persistence, cross-variable dependence, and asymmetric effects within a unified framework.
This work consists of a narrative review that addresses the differences between European cattle and Zebu cattle in their resilience to environmental challenges. It was developed based on scientific articles, theses, dissertations, and technical documents available in recognized databases such as Web of Science, ScienceDirect, Scopus, and PubMed, prioritizing recent studies from 2020 to 2025 that are relevant to the topic. The method used was a narrative review, in which publications addressing the physiological, behavioral, bioclimatic, and adaptive production parameters of each animal group were selected, allowing for a comparative analysis of their main characteristics. The results indicate that European cattle, although highly productive, are less adapted to heat, while zebu cattle stand out for their hardiness, resistance to high temperatures, and lower incidence of diseases. The conclusion is that analyzing these differences is essential to guide breed selection, genetic improvement strategies, and the adoption of more sustainable production systems, favoring greater livestock efficiency and resilience under diverse environmental conditions.
Soil microorganisms play a vital role in enhancing phosphorus (P) availability for plants by regulating soil organic matter decomposition. However, soil P mineralization and solubilization driven by microbial communities under long-term tillage and cover crops are not fully understood. Here, we evaluated soil available P, soil organic matter (SOM), pH, potential activity of beta-glucosidase (BG) and acid phosphatase (ACP) enzymes, bacterial community abundance (16S rRNA), and P mineralizing community (phoC and phoD genes) across three long-term experiments in the Brazilian Cerrado with two soil tillage (no-tillage - NT and conventional tillage - CT), three cover crops in rotation (millet, brachiaria and sunn hemp), and a fallow. Cover crops increased soil ACP activity and immobilized P in their biomass, thereby temporarily lowering available P in the soil. NT increased BG and ACP activities in topsoil but decreased that in subsoil compared to CT. The NT and cover crops increased the pH values and SOM contents in the surface layer, which in turn positively affected the enzymatic activity of the soil. Total bacterial abundance (16S rRNA) was higher under NT in association with grasses (millet and brachiaria). The abundance of the phoD gene was greater than that of the phoC in the soils of the three sites evaluated. The CT system and long-term fallow stimulated the microbial community harboring the phoC gene. On the other hand, the abundance of the phoD gene was significantly increased with the cultivation of brachiaria as a cover crop. Our results suggest that long-term conservation systems, such as NT with cover crops, effectively contribute to biological activity, nutrient cycling and soil quality. It is worth highlighting that this is the first study in Brazil to evaluate the phoC gene abundance, particularly in relation to management systems and cover crops.
Mining activities have expanded rapidly in the Amazon, generating ecological, social, and health concerns. Although the number of publications addressing mining impacts has grown, studies often lack integrative assessments. Here, we provide a systematic synthesis of how the ecological impacts of mining in the Amazon have been framed in the scientific literature over the last 30 years (1995–2025). We analysed 462 peer-reviewed articles and applied Latent Dirichlet Allocation (LDA) to identify the main themes discussed in the literature and the research gaps that structure this field. Twelve topics emerged and were grouped into five categories: Pollution and Toxicology, Land Use, Social–Ecological Systems, Biodiversity and Ecosystem Health, and Monitoring and Assessment. The most prevalent topics were mercury bioaccumulation, human mercury exposure, and post-mining restoration, highlighting persistent concerns with toxicological pathways and ecosystem recovery. In contrast, environmental monitoring impact indicators, disease hotspots, and landscape changes due to resource extraction were the least represented, revealing limited attention to broader-scale ecological processes and early-warning indicators. Semantic similarity analysis showed close relationships among topics linked to contaminant pathways and human health, as well as between landscape alteration and stream biodiversity. The co-occurrence–based dissimilarity analysis revealed weak connections among several topic pairs and highlighted substantial gaps, particularly the infrequent association between monitoring indicators and either toxicological or biodiversity-focused studies. Together, these findings reveal structural imbalances in the scientific agenda. Bridging ecological, toxicological, and socio-political perspectives is essential to support evidence-based responses and safeguard both biodiversity and human well-being in the Amazon.
