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It has historically been frequent among geotechnical practitioners, that the stability analysis of the slopes of an open pit is performed using a two dimensional section representing the highest and steepest walls within a certain geological setting. However, the literature shows that to predict rupture events in an open pit, a three-dimensional analysis would better represent the actual conditions, as the spatial distribution of the lithology and the structural features play an important role when defining the stability of the slopes. This paper presents the case study of an open pit located in Brazil, which experienced instabilities between the years 2001 and 2019. An evaluation of the behavior of the open pit was performed by calibrating the strength parameters to represent the best documented rupture events. The three-dimensional model was made using the finite difference method. The results show that there is a good correlation between the results of the model and the reports of past instabilities. Finally, recommendations are presented for the inter-ramp angles for each lithology based on the calibrated stability analysis performed. This work seeks to contribute to the knowledge in evaluation techniques for the three-dimensional behavior of open pits. [ABSTRACT FROM AUTHOR]

The Port of Paranaguá serves as Brazil's primary outlet for soy oil exports, accounting for nearly 70% of all shipments in 2021. While less common than mineral oil spills, vegetable oil spills can have similarly devastating environmental effects. This risk underscores the need for effective planning and management of activities involving vegetable oil handling in the region. To address this need, this study developed results based on a forecasting setup focused on describing the behaviour of soy oil spills in the estuarine complex of Paranaguá. The system uses the open TELEMAC-MASCARET three-dimensional numerical modelling system to solve oil movement equations, coupling the hydrodynamic module (Telemac-3d) with the oil module (ECOS). The system is automated through computational routines written in Python and the bash command language, enabling users to initiate simulations and generate dispersion maps to track soybean oil in hypothetical spill scenarios. The processing results were satisfactory, demonstrating the potential for this tool to contribute to minimising the impacts of soybean oil spills in the Bay of Paranaguá. This system can support better decision-making in response efforts, reduce environmental damage, and enhance the protection of local ecosystems. [ABSTRACT FROM AUTHOR]

Seed transport by hydrochory is a key mechanism of long‐distance dispersal constrained by attributes of the seed and hydrodynamics of the river, influenced by seasonal precipitation and hydrological pulses. However, the extent to which a hydrodynamic model can predict seed dispersal influenced by a tributary is unknown.The study was conducted along a 10‐km stretch of the Falsino River in Amapá, Brazil. Hydrodynamic parameters from the 2021 rainy season were used to calibrate a three‐dimensional numerical model (SisBaHia) and simulate hydrochory of Macrolobium bifolium, a widely distributed species in the Amazon floodplains. This model was coupled with a Lagrangian dispersal model to estimate the average transport distance of the fruit plume. The simulated results were compared statistically with those of dispersal quantified in the field.The field experiment coincided with the maximum hydrological pulse, providing with a maximum potential distance of longitudinal dispersal fruit of c. 10 km in 2 hr. The orders of magnitude of the mean plume transport (observed and numerically simulated centre of mass) were compatible with each other over six longitudinal tracking sections (4.0% ≤ estimated × observed error ≤ 16.5%). Different channel stretches had distinct hydraulic characteristics that influenced spatial dispersal dynamics and are likely to be factors influencing the distribution of M. bifolium in these environments.The present research is a contribution to understanding fluvial hydrodynamics and hydrochory by M. bifolium, whose seed dispersal syndrome is an adaptive characteristic that might explain its abundance and richness in these Amazonian riparian zones. We used M. bifolium as a model species to understand the role of seasonal flood pulse and fluvial hydrodynamics related to hydrochory favouring. [ABSTRACT FROM AUTHOR]

Background: Proximal humerus fractures (PHF) are frequent, however, several studies show low inter-rater agreement in the diagnosis and treatment of these injuries. Differences are usually related to the experience of the evaluators and/or the diagnostic methods used. This study was designed to investigate the hypothesis that shoulder surgeons and diagnostic imaging specialists using 3D printing models and shoulder CT scans in assessing proximal humerus fractures. Methods: We obtained 75 tomographic exams of PHF to print three-dimensional models. After, two shoulder surgeons and two specialists in musculoskeletal imaging diagnostics analyzed CT scans and 3D models according to the Neer and AO/OTA group classification and suggested a treatment recommendation for each fracture based on the two diagnostic methods. Results: The classification agreement for PHF using 3D printing models among the 4 specialists was moderate (global k = 0.470 and 0.544, respectively for AO/OTA and Neer classification) and higher than the CT classification agreement (global k = 0.436 and 0.464, respectively for AO/OTA and Neer). The inter-rater agreement between the two shoulder surgeons were substantial. For the AO/OTA classification, the inter-rater agreement using 3D printing models was higher (k = 0.700) than observed for CT (k = 0.631). For Neer classification, inter-rater agreement with 3D models was similarly higher (k = 0.784) than CT images (k = 0.620). On the other hand, the inter-rater agreement between the two specialists in diagnostic imaging was moderate. In the AO/OTA classification, the agreement using CT was higher (k = 0.532) than using 3D printing models (k = 0.443), while for Neer classification, the agreement was similar for both 3D models (k = 0.478) and CT images (k = 0.421). Finally, the inter-rater agreement in the treatment of PHF by the 2 surgeons was higher for both classifications using 3D printing models (AO/OTA—k = 0.818 for 3D models and k = 0.537 for CT images). For Neer classification, we saw k = 0.727 for 3D printing models and k = 0.651 for CT images. Conclusion: The insights from this diagnostic pilot study imply that for shoulder surgeons, 3D printing models improved the diagnostic agreement, especially the treatment indication for PHF compared to CT for both AO/OTA and Neer classifications On the other hand, for specialists in diagnostic imaging, the use of 3D printing models was similar to CT scans for diagnostic agreement using both classifications. Trial registration: Brazil Platform under no. CAAE 12273519.7.0000.5505. [ABSTRACT FROM AUTHOR]

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Background: The agreement for the treatment of proximal humerus fractures is low. Interpretation of exams used for diagnosis can be directly associated with this limitation. This study proposes to compare the agreement between experts and residents in orthopedics for treatment indication of proximal humerus fractures, utilizing 3D-models, holography (augmented reality), x-rays, and tomography as diagnostic methods. Methods: Twenty orthopedists (ten experts in shoulder and elbow surgery and ten experts in traumatology) and thirty resident physicians in orthopedics evaluated nine fractures of the proximal humerus, randomly distributed as x-rays, tomography, 3D-models and holography, using the Neer and AO / OTA Classifications. After, we evaluated the interobserver agreement between treatment options (conservative, osteosynthesis and arthroplasty) and whether the experience of the evaluators interfered with the results. Results: The interobserver agreement analysis showed the following kappa-values: κ = 0.362 and κ = 0.306 for experts and residents (3D-models); κ = 0.240 and κ = 0.221 (X-ray); κ = 0.233 and κ = 0.123 (Tomography) and κ = 0.321 and κ = 0.160 (Holography), for experts and residents respectively. Moreover, residents and specialists were discordant in the treatment indication using Tomography as a diagnostic method (p = 0.003). The same was not seen for the other diagnostic methods (p > 0.05). Conclusions: Three-dimensional models showed, overall, the highest interobserver agreement (experts versus residents in orthopedics) for the choice of treatment of proximal humerus fractures compared to X-ray, Tomography, and Holography. Agreement in the choice of treatment among experts that used Tomography and Holography as diagnostic methods were two times higher compared to residents. Trial registration: Registered in Brazil Platform under no. CAAE 12273519.7.0000.5505. [ABSTRACT FROM AUTHOR]

The Pelotas Batholith corresponds to the eastern margin of the Dom Feliciano Belt in southernmost Brazil. It comprises multiple intrusions formed by successive tectonic-magmatic processes during the Brasiliano / Pan-African Cycle. One of these intrusive igneous bodies is the Piquiri Syenite Massif (PSM), recently described as a multi-intrusive body formed by three successive pulses, dated by LA-MC-ICP-MS (U-Pb in zircon), with the oldest pulse located at the margins and the youngest in the centre of the intrusion. Pulse 1 (609.3 ± 1.5 Ma) comprises fine- to medium-grained equigranular syenite to quartz syenite and alkali-feldspar quartz syenite, with colour index M′15–30. Pulse 2 (603.4 ± 3.9 Ma) comprises medium- to coarse-grained equigranular alkali-feldspar syenite and alkali-feldspar quartz syenite, with colour index M′ 5–15 and fragments of Pulse 1 varieties. Pulse 3 (588.8 ± 3.1 to 583.2 ± 1.8)comprises medium- to coarse-grained inequigranular quartz syenites, with colour index M′ 2–10, containing fragments of pulses 1 and 2 varieties. As defined by the AMS data, the PSM magnetic fabric is concordant with the magmatic fabric, parallel to the outer edges of the body, dipping towards the centre. However, the construction and emplacement of the body have been the subject of different interpretations. The main objective of this work is to relate the general morphology of the massif and the behaviour of the pulses within the massif with the processes of formation and ascent of the magmas that have built it. For this, terrestrial geophysical surveys were carried out to obtain gravimetric data, with which the Bouguer Anomaly map was generated. Modelling by gravimetric inversion was carried out in nine profiles using tools from the Oasis Montaj software, which was the basis for constructing a three-dimensional geological model using the Leapfrog Geo software. Associating the geological model with the magmatic and magnetic foliations, including the magnetic lineation, it was possible to determine a change in behaviour between the youngest and the two oldest pulses related to the ascension process. In addition, the body's general shape, with the greatest depths located in the eastern region, allowed us to relate the rise of magma to a structure in the region. • Nine sections across the Piquiri Syenite Massif were used to model gravity anomalies. • Gravity anomaly model correlates with anisotropy of magnetic susceptibility data. • The pluton was built by three successive syenite magma pulses. • The magma pulses were added by two different emplacement mechanisms. [ABSTRACT FROM AUTHOR]

Highlights • Probabilistic methodology indicated a realistic stability condition of a rock tunnel. • Results of the total volume of failed rock presented a variation as large as 3000%. • First and second moments of the failed volume converged in less than 200 model runs. • 200 stability analyses were performed in 21 h by a cloud cluster of 40 instances. • Classic Lattice Spring Model and cloud computing afford fast probabilistic analyses. Abstract In this paper, the Classic Lattice Spring Model is developed in order to be applied to probabilistic stability analyses of rock tunnels in low in situ stress environments, where the falling of blocks is the main failure mechanism. For this objective, the method is combined with the Synthetic Rock Mass technique and Barton-Bandis joint constitutive model, giving it a series of advantages: simulations with deformable blocks; possible formation of tension cracks; and an appropriate constitutive model for the mechanical behavior of joints. The use of cloud computing technology is proposed for efficient probabilistic analyses using the Monte Carlo simulation. A case study is presented based on an unsupported section of a shallow rock tunnel excavated in the state of Espírito Santo, Brazil. A 3D probabilistic stability analysis of the tunnel is performed with the proposed methodology. From the results, a positional probability map is elaborated, which indicates the likelihood of block failure around the excavation cross-section. The unstable zones indicated by the map are then compared to the failed region of the real tunnel so as to demonstrate the competence of the methodology. [ABSTRACT FROM AUTHOR]

The elderly population is increasing worldwide, leading to a growing concern about the quality of life of this segment of the population, including housing issues. Aging brings several perceptual, cognitive and motor limitations that make it difficult to understand spatial information. These limitations have an impact on the elderly's understanding of graphic representations of dwelling projects, as effectiveness in the communication between architects and elderly users may be jeopardized. With this in mind, a study on elderly users' understanding of project representations was conducted in Brazil. The study investigated the understanding of three project representations: 2D technical drawings; electronic model with 3D static perspectives of the space; and digital simulation of virtual tour through a house project. 15 people took part in the study. In general, the results showed poor comprehension of all representations, the virtual tour representation yielding the most positive outcomes. The possible influence of age and gender on the performance of the participants is discussed. It is concluded that ageing and realism in depiction affect elderly users' assimilation of information presented in architectural projects, corroborating the literature. [ABSTRACT FROM AUTHOR]

Metamorphic–deformation paths and interpretations of regional structures are essential for the understanding of how orogens evolve. While in active orogens, structures can be easily mapped for hundreds of kilometres, regional structures in ancient mountain belts may appear only as subsurface geophysical data. In this paper, we constrain the metamorphic–deformation history of the southeastern part of the Passo Feio Complex located in the Neoproterozoic Dom Feliciano Belt in southernmost Brazil. The complex is crosscut by a block-limiting structure defined by magnetometric data, the Caçapava Lineament. Our petrographic interpretations and thermodynamic modelling of pelitic schists of the Passo Feio Complex indicate the beginning of garnet growth at ca. 530–550 °C and 3–4.3 kbar during D 1 , and metamorphic peak at ca. 560–570 °C and 5–5.5 kbar (M 1), during progression to D 2. After M 1 (~17–19 km depth), the complex was exhumed to at least 14 km (~4 kbar) depth, as the contact metamorphism by the Caçapava Granite (ca. 562 Ma) produced andalusite. The correlation of D 3 structures of the Passo Feio Complex (S 3 and L 3), magmatic structures in the Caçapava Granite, orientation of geophysical anomalies in the region and kinematics of S 3 corroborate the interpretation of the Caçapava Lineament as a dextral shear zone. Due to the location of anomalies and previous three-dimensional modelling of the granitic body, we interpret that a curved ENE to NS branch of the NE-striking Caçapava Shear Zone is responsible for the accommodation of the Caçapava Granite. Lastly, we discuss the regional implications of such interpretation, which brings up the question of block-limiting character of the Caçapava Shear Zone and the geotectonic position of the Passo Feio Complex. • Onset of Garnet growth from 490 to 550 °C, 2.5–4.3 kbar. • M 1 peak metamorphic conditions of 500–510 °C, 5–6.4 kbar in a Gt phyllite. • M1 peak metamorphic conditions of 560–570 °C/5–5.5 kbar in a Gt–St schist. • Regional metamorphism not compatible with low-P conditions; Andalusite related to contact. • Caçapava Lineament origin as a dextral transcurrent shear zone. [ABSTRACT FROM AUTHOR]