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The Brazilian Equatorial Shelf (BES) is one among the macrotidal regions worldwide. This study used a high-resolution numerical configuration of the ocean model ROMS (Regional Ocean Modeling System) forced with realistic surface and lateral forcing, as well as with tides and river discharges. Tidal heights of more than 2 m were found in three regions in BES due to the large tidal amplification across the estuarine channels inside each region: Amazon, Pará, and Maranhão, and for a considerable time fraction. Heights between 4 and 5 m occurred with a frequency greater than 20%–30% in some regions. All hypothetical barrages proposed in this study were capable of an annual power production, in two-way mode, higher than La Rance (533 GWh year, two-way operation, France) and Sihwa (553 GWh year, flood-only operation, South Korea), except one with the same production as Sihwa barrage. The installation effort was evaluated using the Gibrat ratio, the ratio between the length of the barrage and its annual energy production. Among the proposed barrages, the most efficient ones have an annual power generation greater than 1500 GWh year and a Gibrat ratios between 1.17 and 3.26, much lower than the Gibrat ratio of Sihwa tidal barrage.

Recreational spearfishing is a fishing method that occurs globally, yet receives considerably less attention in the scientific literature relative to other recreational fishing methods, such as angling. Lack of scientific information on spearfishing may negatively affect the development and management of marine recreational fisheries. We conducted a systematic review of 102 peer-reviewed papers published between 1967 and 2022 pertaining to marine recreational spearfishing. Based on this literature review, we provide an overview of key insights across social, economic, and ecological dimensions of marine recreational spearfishing. While spearfishers represent less than 5% of marine recreational fishers, the participants are younger and may differ from recreational anglers in their motivations, with suggestions of increased well-being generated from a close connection with the sea during underwater fishing. Recreational spearfishers mostly target species of moderate to high levels of vulnerability that are mid to high trophic level carnivores. Though spearfishers can deliberately target larger individuals of exploited populations, this is not a generalizable pattern. Despite a growing body of research on the ecological impacts of marine recreational spearfishing, there is limited knowledge of these effects and their mechanisms across biological levels of organization (e.g., individual, population, community and ecosystem) compared with those of other fishing methods. Recreational spearfishers can contribute to advances in marine ecological knowledge, and inclusive participatory management could represent a key step towards transformative sustainable development of marine recreational spearfishing. Throughout the review, we identify gaps in the research and areas where future research is needed to better inform the socio-economic importance, ecosystem impacts and future management of marine recreational spearfishing

The present work describes the development of a hybrid and pH-responsive system for rifampicin using the clay mineral ‘montmorillonite’ as a nanocarrier. The influence of operational variables on the drug incorporation process was evaluated using 2 factorial designs. Under optimized conditions, the experiment allowed an incorporated drug dose equivalent to 98.60 ± 1.21 mg/g. Hybrid systems were characterized by different characterization techniques (FTIR, XRD, TGA, DSC, and SEM) to elucidate the mechanism of interaction between the compounds used. Through in vitro release studies, it was possible to verify the efficacy of the pH-dependent system obtained, with approximately 70% of the drug released after sixteen hours in simulated intestinal fluid. The adjustment of the experimental release data to the theoretical model of Higuchi and Korsmeyer–Peppas indicated that the release of rifampicin occurs in a prolonged form from montmorillonite. Elucidation of the interactions between the drug and this raw clay reinforces its viability as a novel carrier to develop an anti-TB/clay hybrid system with good physical and chemical stability.

The Brazilian Equatorial Shelf (BES) is a very dynamic region due to the influence of various forcings: trade winds, macrotides, the Amazon River, and the North Brazil Current (NBC). To investigate each forcing's role in BES circulation, a control simulation and three sensitivity simulations (without rivers, without tides, and without winds) were performed using the Regional Ocean Modeling System (ROMS) with a horizontal resolution of 1/24° and realistic forcings. The results showed that the NBC advected low-salinity waters from the Amazon River northwestward to Caribbean Sea and occasionally eastward through the NBC retroflection. The NBC exhibited the strongest flow when all forcings were included in the simulation. On the other hand, southeasterly winds inhibited the NBC retroflection system and, thus reducing its contribution to North Equatorial Counter Current (NECC) and Equatorial Undercurrent (EUC). The simulation without tides showed a plume more advected by the NBC and constricted to the first 10 m of the water column, while in the simulation without wind the plume was less advected northwestward by the weakened NBC and spread more toward the shelf break. The correlation analysis highlighted the complexity of the system, the complementarity of the forcings and their time-variable interdependence. The three sensitivity simulations and correlation analysis demonstrated the wind to be the main mechanism of the circulation in the BES. The sensitivity simulations also gave insight of how circulation would respond in a future scenario if climate changes persist. Previous studies suggest that the reduced Amazon runoff may indirectly weaken Atlantic ITCZ and thus trade winds causing a weakened circulation in tropical Atlantic. Our results show that this weakened circulation would advect even less fresh water northward, worsening the disturbances in North Atlantic due to the reduced freshwater supply.

The Proterozoic Borborema province of NE Brazil was under extensional stresses during the Mesozoic, causing stretching and thinning of the lithosphere. During Cenozoic times, compression associated with the development of the South Atlantic and collision along the Andean front dominated throughout the Province. One of the main consequences of such compression might have been the formation of the Chapada de Araripe, an inverted rift basin located in the Western Province. We undertook a passive seismic experiment along a NS profile crossing the Borborema province and a short EW profile across the Chapada de Araripe, with the goal of providing constraints on the origin of the Chapada de Araripe. A variety of mechanisms can contribute to basin uplift, so understinding basin inversion is in turn important for understanding the tectonic evolution and geodynamics of NE Brazil. Through joint inversion of receiver functions and surface-wave dispersion, we show that the crust is typically 34–38 km thick under the western Province; in contrast, the crust is 43–46 km thick under the northern craton. No apparent crustal thinning is observed under the Araripe Basin, due to the presence of a relatively thick (10–14 km) high-velocity (4.1–4.3 km/s) lowermost crust. Our velocity models also image a drop in S-velocity (from 4.6 km/s to 4.3 km/s) at 135–145 km depth under the southern half of the profile, which we interpret as a mid-lithospheric discontinuity, and at 120–140 km depth under the Araripe Basin, likely representing the lithosphere-asthenosphere boundary. Our findings confirm the presence of thin lithosphere under the Araripe Basin - originally postulated by a collocated MT survey - that might have facilitated tectonic inversion of this basin through regional stress concentration and thermal buoyancy. These findings also suggest additional buoyancy contributed by a mafic lowermost crust right under the basin

Pyrolysis processes are an alternative to minimize the environmental problem associated to agrifood industrial wastes. The main product resulting from these processes is a high-value liquid product, called bio-oil. Recently, the use of comprehensive two-dimensional liquid chromatography (LC × LC) has been demonstrated as a useful tool to improve the characterization of the water-soluble phases of bio-oils, considering their complexity and high water content. However, the precise composition of bio-oils from different agrifood byproducts is still unknown. In the present study, the qualitative and quantitative screening of eight aqueous phases from different biomasses, not yet reported in the literature, using LC × LC is presented. The two-dimensional approach was based on the use of two reverse phase separations. An amide column in the first dimension together with a C18 column in the second dimension were employed. Thanks to the use of diode array and mass spectrometry detection, 28 compounds were identified and quantified in the aqueous phase samples with good figures of merit. Samples showed a distinct quali-quantitative composition and a great predominance of compounds belonging to aldehydes, ketones and phenols, most of them with high polarity.

Glycerol availabity, a waste generated in the production of biodiesel, has increased during last years. In this work, Chemical Looping Reforming (CLR) of glycerol has been demonstrated in a 1 kW continuous unit during 35 h using a Ni-based oxygen carrier to obtain a high purity syngas without CO emissions. Complete conversion of the glycerol and syngas composition close to thermodynamic equilibrium was obtained in the fuel reactor. Moreover, pure N was obtained as product in the air reactor. The influence of the main operating variables on the composition and flow rates of synthesis gas was evaluated. The oxygen-to-glycerol molar ratio was the main parameter since the amount of lattice oxygen transferred by the oxygen carrier in the fuel reactor controlled the syngas composition. The increase of the water-to-glycerol ratio produced an increase in the production of H and CO with a decrease in the CO content, increasing both the syngas yield and the H/CO molar ratio in the gas. Fuel reactor temperature affected mainly to the CH content, being lower as higher was the temperature. Close to autothermal conditions, it is possible to obtain a syngas composed by H ≈ 48–50 vol%; CO ≈ 30–35 vol%; CO ≈ 14–18 vol%; and CH ≈ 1.6–3 vol%. In addition, different H/CO ratios can be obtained by modifying the HO/glycerol ratio and temperature. A H/CO ratio of 2 could be reached using either a HO/glycerol ratio of 1.5 at 750 °C or a HO/glycerol ratio of 2 at 800 °C.

Background. The Amazon River is one of the largest in the world and receives huge amounts of terrestrial organic matter (TeOM) from the surrounding rainforest. Despite this TeOM is typically recalcitrant (i.e. resistant to degradation), only a small fraction of it reaches the ocean, pointing to a substantial TeOM degradation by the river microbiome. Yet, microbial genes involved in TeOM degradation in the Amazon River were barely known. Here, we examined the Amazon River microbiome by analysing 106 metagenomes from 30 sampling points distributed along the river. Results. We constructed the Amazon River basin Microbial non-redundant Gene Catalogue (AMnrGC) that includes ~ 3.7 million non-redundant genes, affiliating mostly to bacteria. We found that the Amazon River microbiome contains a substantial gene-novelty compared to other relevant known environments (rivers and rainforest soil). Genes encoding for proteins potentially involved in lignin degradation pathways were correlated to tripartite tricarboxylates transporters and hemicellulose degradation machinery, pointing to a possible priming effect. Based on this, we propose a model on how the degradation of recalcitrant TeOM could be modulated by labile compounds in the Amazon River waters. Our results also suggest changes of the microbial community and its genomic potential along the river course. Conclusions. Our work contributes to expand significantly our comprehension of the world’s largest river microbiome and its potential metabolism related to TeOM degradation. Furthermore, the produced gene catalogue (AMnrGC) represents an important resource for future research in tropical rivers

The use of mathematical models in environmental studies allows significant scientific contributions to the physical planning of an area, since they help to understand the impact of changes in land cover and predict future trends of changes in ecosystems. The study area includes portions of the municipalities of Duque de Caxias, Nova Iguaçu, and Belford Roxo, located in the state of Rio de Janeiro, Brazil, and aims to carry out experiments in land cover changes in the medium-term (10 years) within the catchment area of ORBEL pipelines. The modeling performed in this study was developed using the software Dinamica EGO. For model calibration, we used the weights of evidence method. Positive values foster certain transitions, while negative values indicate low probability of transition. Model validation was executed by means of the fuzzy similarity method using exponential decay. The results show that for the study period (1998-2010) the rate of change for the transition of the class 'others to woody vegetation' is much higher than for the other class transitions observed in the same periods. One annual land cover scenario was generated for the year 2020. The scenario indicated the growth of suburbs near the ring road around Rio de Janeiro, especially in the municipality of Duque de Caxias.

A cada passo do processo produtivo de petróleo e gás natural, a metrologia se faz presente em diversas formas: primeiro, na exploração, com o desafio de encontrar petróleo no subsolo; segundo, na determinação dos volumes produzidos, para possibilitar o exato pagamento das Participações Governamentais (Royalties, etc.) e impostos; terceiro, na segurança do processo e do meio-ambiente; finalmente, na venda dos produtos finais ao distribuidor e consumidor. Portanto, a medição é a “caixa registradora” das empresas, aumentando de exatidão e exigência a cada passo que se aproxima dos pontos de entrega, onde diferenças de 0,1% são discutidas. O trabalho apresenta as abordagens utilizadas na avaliação das incertezas de medição nos volumes obtidos de petróleo e gás natural nos processos de produção no Brasil e em nível internacional.

Many multivariate methods have been applied to small-scale fishery data in an attempt to distinguish factors that characterize the fishing activity and influence catch composition. While such approaches are important, they are still incomplete for including the spatial structuring in the analysis, a non-random fundamental and functional component of the ecosystem. This study fills this gap by identifying, describing, and quantifying factors that influence the fleet type of tropical small-scale fisheries using a multivariate spatial approach. The example data came from two Brazilian States where two main fleets, open water canoes and motorized boats, operate. Different complex combinations of fishing, environmental and spatial factors affect the structure of the fish catch composition of each fleet. Motorized boats showed strong spatially-structured species catch composition in comparison with open water canoes. Similar environmental factors, such as type of the seabed and depth, but different fishing variables (gear vs crew size), affected the species catch composition of these vessel categories. Despite some overlap, each fleet focuses on a relatively distinct set of species groups and exploits habitats at different spatial scales. These results suggest that different sets of regulations should be considered for each fleet type within a specific spatial scale. It also shows that multi-species models that aggregate groups of species is a more efficient alternative than single-species assessment models for small-scale fisheries, as these are multi-specific and multi-gear, with scattered landing harbors, features that make such fisheries a complex challenge for management.

In chemical-looping auto-thermal reforming (CLRa), hydrogen is produced without the need of an exterior heat supply. Thus, an important aspect to be considered in the design of a CLRa system is the heat balance. In this work, mass and heat balances have been done to determine the auto-thermal operating conditions that maximize H2 production in a CLRa system working with a Ni-based oxygen carrier with a 20 wt % of active metal oxide (NiO). It was found that the oxygen-to-methane molar ratio should be higher than 1.25 to reach auto-thermal conditions, which means that the H2 yield is 2.7 mol H2/mol CH4. The control of the oxygen-to-methane ratio by the air flow to the air-reactor was preferred against controlling the oxygen transferred by the solids circulation rate because a lower excess of air was needed in the first case to reach auto-thermal conditions.

This paper presents the results of the performance evaluation in terms of daylighting of the Petrobras New Research Centre (CENPES II) building design in the tropical climate of Rio Janeiro, Brazil, under a typical partially cloudy and bright sky. The architectural design encompasses an área over 100,000 m2, distributed among ten new buildings. According to the design brief, daylighting should be maximized in all interior spaces whenever allowed by functional requirements, providing both visual comfort and energy efficiency. In that case, the design challenges were related to the need for solar protection and avoidance of glare, due to climatic conditions, including a fairly bright sky. This paper is focused on the two main building of the Center. The performance assessments were carried out with the support of advanced computer simulations, being compared to national and international design criteria. The results indicate the positive effects of the adoption of some conventional design strategies, which are not widely used in commercial building design in Brazil., Este artigo apresenta os resultados do desempenho de iluminação natural do projeto do novo centro de pesquisas na Petrobras, CENPES II, no clima tropical do Rio de Janeiro, sob as condições de céu típico parcialmente nublado e com grande luminosidade. Tais estudos foram parte de um trabalho mais amplo de pesquisa e consultoria, envolvendo um número de questões ambientais incluindo luz natural, desempenho térmico e desempenho energético. O projeto arquitetônico foi objeto de concurso nacional em 2004, englobando mais de 100.000m2 de área construída a ser adicionada às instalações do centro de pesquisas existente (CENPES I), trazendo mais dez novos edifícios. De acordo com o edital do concurso, o acesso da iluminação natural deveria ser maximizado em todos os espaços interiores, sempre que permitido pelas exigências da função, oferecendo conforto visual e eficiência energética. Nesse caso, os desafios do projeto para com o desempenho ambiental estão relacionados à necessidade de proteção solar e a não ocorrência de ofuscamento, devido às condições climáticas e ao céu com grande luminosidade. Nesse contexto, o trabalho apresentado nesse artigo esta focado nos dois edifícios principais do complexo: Prédio Central e Laboratorios. As avaliações de iluminação foram realizadas com o suporte de técnicas avançadas de simulação e comparadas com critérios de desempenho nacionais e internacionais. Ao final, os estudos de simulação mostraram os efeitos positivos de estratégias convencionais de projeto, resultantes de um rigoroso processo de projeto.