Anais da Academia Brasileira de Ciencias最新文献

In Brazil, the recurring environmental impacts due to insufficient inspection and inadequate management of potentially toxic mining tailings have raised significant concerns. The study concentrates on examining the mobility of elements in flotation (ft) and cyanidation (ct) tailings from gold mining operations, following successive extractions. The influence of extractants on the release of elements from both ft and ct samples, including As, Cd, Cu, Cr, Pb, Se, and Zn, was examined and compared to the ABNT NBR 10004:2004 standard. The samples were obtained from a gold mining company in Brazil. Sequential extraction tests for ft and ct samples were conducted to simulate weathering effects, using solutions of 0.1 mol L-1 citric acid, 0.1 mol L-1 acetic acid, 0.1 mol L-1 oxalic acid, 0.1 mol L-1 ammonium acetate, and distilled water at pH 5.5. The results revealed that the established limits for Pb and Cd under the ABNT NBR 10004:2004 standard were exceeded in a 1:1 tailing-to-extractor ratio. In ct samples, both elements surpassed the standard limits for all extractors, except for Cd when using water. In ft samples, Pb exceeded the limits with all acids, while Cd exceeded the limits only in the presence of acetic acid and ammonium acetate.

This study examined the taxonomic composition and ecological aspects of planktonic green algae (Chlorophyta) in four urban ponds (Parque da Lagoa, Lagoa Grande, Laguneville, and Pindoba) in Feira de Santana, Bahia State, Brazil. We analyzed 96 samples collected bimonthly in 2022 and identified 54 taxa, with the majority (42) classified as uncommon or sporadic. The most common species were Monoraphidium circinale and Lemmermannia komarekii, found in 100% and 95.8% of samples, respectively. Parque da Lagoa had the highest number of taxa (43), followed by Lagoa Grande (40), Laguneville (31), and Pindoba (30). Most taxa were found in water with high levels of oxygenation (5.8-12.3 mg L-1) and conductivity (400-1000 μS cm-1), neutral to slightly alkaline conditions (pH 7-8), and moderate water temperature (26-27 °C). Significant differences in the composition of planktonic green algae and limnological variables were observed among ponds. These studies underscore the importance of implementing actions aimed at the restoration and conservation of urban ponds in Feira de Santana to avoid biodiversity loss and eutrophication while ensuring the provision of critical ecosystem services, such as local climate regulation.

Pollen dispersal by insects determines the patterns of reproductive encounters between plants with flowers that have spatially or temporally segregated sexes. Pollinators exhibit varied responses to environmental gradients, such as those in grassland-forest ecotones. Individual-based interaction networks are useful yet underexplored tools to understand how interactions vary across these gradients. To test how a grassland-forest ecotone gradient affects these interactions, we studied pollination networks of Butia odorata individuals, a key palm tree species in a threatened South American grassland ecosystem. We assessed, through Structural Equation Models (SEMs), how network metrics (specialization and modularity) and pollinator richness and abundance (total, peripheral, core) respond to gradients of habitat and population structure in the grassland-forest ecotone. Networks with more spatially isolated palms showed greater specialization and modularity. Pollinator richness was dependent on the habitat context and pollinator role. The peripheral pollinators were negatively affected by palm density. The core pollinators were positively affected by tree cover, which, in turn, was positively associated with palm density and proximity to the forest. Our results suggest that palm population density can modulate the presence of peripheral pollinators, while increased tree cover in the grassland matrix can promote pollinator diversity by decreasing the dominance of core species.

Fish is an important food item in the diet of humans, whereas it is also a major source of exposure to toxic chemicals. Persistent organic pollutants (POPs) and mercury (Hg) are known to have hotspots of contamination across the coast of Pernambuco, Brazil. This study investigated organochlorines and Hg in muscle samples from respectively 17 and 14 individuals of the stingray Hypanus berthalutzae - a fishing resource used to prepare a traditional dish in the local cuisine. DDTs, HCHs and mirex were not detected in the samples. Mean concentrations of PCBs, CHLs and total Hg were 0.032, 0.004 and 60 ng g-1 wet weight (ww), respectively. Ecological and biological parameters are important factors in the bioaccumulation of pollutants in fish. Although the concentrations of POPs and Hg do not present a health risk to consumers in general, they may pose a health risk to certain groups such as children and people who eat H. berthalutzae daily. This paper is relevant for the conservation of an endemic stingray species widely consumed in northeastern Brazil and classified as vulnerable in terms of risk of extinction.

The economic development of human activities contributes to the discharge of many anthropogenic pollutants. To assess the environmental risks in the Jaguaribe River, the most important river in the hydrographic region of the Eastern Northeast Atlantic, a bibliographic review of scientific articles and a series of ecotoxicological bioassays were conducted. The bioassays were conducted using sediment samples at six collection sites along the river, while the bibliographic review was used to identify the presence of anthropogenic contaminants in sediment and tissue samples of aquatic organisms within two km of each of the sediment collection sites. The bibliographic review showed the presence of thirty-eight anthropogenic pollutants in sediment samples and seven in tissue samples of aquatic organisms. The ecotoxicological bioassays showed that the sediment samples produced lethal and sublethal effects in the four tested representatives of the different trophic levels: Daphnia magna, Artemia salina, Allium cepa and Cucumis sativus. The presence of multiple anthropogenic pollutants in the Jaguaribe River and the observed lethal and sublethal effects in ecotoxicological bioassays suggest potential risks not only to the aquatic ecosystem but also to human health. Humans may be exposed to these contaminants through the consumption of water and aquatic organisms, leading to potential health issues such as increased cancer risk. The findings underscore the urgent need for regular monitoring and effective pollution control measures to mitigate these health risks and protect the well-being of local communities.

Morus nigra L., commonly known as black mulberry, is a significant plant species in the pharmaceutical and cosmetic industries. It is also considered an Unconventional Food Plant with potential applications in nutrition. The diversity of bioactive compounds present accounts for its antioxidant, anti-inflammatory, analgesic, and antitumor properties. Thus, this study aimed to analyze technological and scientific information on M. nigra by examining patent documents and scientific papers. The European Patent Office®, the National Institute of Industrial Property®, and Scopus® were utilized as research sources, employing the search terms "Morus nigra" for the former two and "Morus nigra" and "food" for the latter. A total of 210 documents were validated for the research. China leads in patent applications (44%), while Turkey leads in scientific publications (30%). Patents are concentrated in cosmetics, pharmaceuticals, food, and beverages, while scientific publications in the areas of Agriculture and Biological Sciences, Chemistry and Biochemistry, Genetics and Molecular Biology. The global blackberry trade is on the rise, attracting significant interest from multinational companies. Therefore, academic research and technological innovation must keep pace with market demand, given the promising use of black mulberry.

In forensics, genetic human identification is generally achieved by nuclear STR DNA typing. However, forensic samples often yield DNA in exiguous quantity and low quality, impairing the generation of conclusive DNA profiles by STR typing. In such cases, mitochondrial DNA (mtDNA) can be used as an alternative solution in forensic human identification. The high copy number, small circular DNA, high mutation rate, maternal inheritance, and absence of recombination are mtDNA's key features in forensics. In this work, we review mtDNA characteristics, forensic applications, sequencing methodologies and present some relevant examples in the forensic science literature.

The family Gripopterygidae occurs in the Austral Hemisphere and comprises about 330 species within 57 genera. About 110 species belonging to 28 genera are native to South America. Some are endemic to the Andean Region, while others reside in the Neotropical Region. In this latter region, Gripopterygidae has primarily been documented in the Brazilian Atlantic Forest, inland areas, and specific regions in northeastern Argentina, southern Paraguay, and Uruguay. Our research involved examining specimens from diverse Brazilian locations and compiling data sourced from the Plecoptera literature of the Neotropical Region. In this study, we present a comprehensive list of 62 Gripopterygidae species across four genera documented in Neotropical Region: 1) Gripopteryx Pictet, comprising 18 described species; 2) Guaranyperla Froehlich, comprising three species; 3) Paragripopteryx Enderlein, which includes 15 species, and 4) Tupiperla Froehlich, with 26 species. Additionally, we have morphologically characterized a specimen of Gripopteryx elisae Illies collected in Santa Catarina State, Brazil. We provide detailed information about the life stages associated with each species, documented records by administrative and natural areas, and information about the institutions housing the type series of Neotropical gripopterygids.

Astyanax bimaculatus are small characids known as piabas or lambaris that form a complex encompassing 18 species, including cryptic species. The present study aimed to use DNA barcode to analyze populations of A. bimaculatus found in Maranhão hydrographic basins, comparing molecular diversity indices between populations from the other Brazilian basins. The results revealed the formation of 32 haplotypes (h = 0.9289; π = 0.0523). Seven haplogroups were formed with intrapopulation genetic distance ranging from 0 to 2%. The Maranhão populations of the Western Northeast Atlantic Region basins separated from the other analyzed basins, corroborating with the groups generated in BAPS and with the Bayesian Inference tree. The occurrence of exclusive OTUs for the Maranhão populations of the Western Northeast Atlantic Region was confirmed through delimitation models. Thus, the data from this study provide information on the genetic diversity of the A. bimaculatus complex with the detection of a different lineage for the State of Maranhão, contributing to the understanding of the group's systematics.

Air contamination in confined environments can lead to severe health damage. Searching for effective and sustainable technologies that might bring quality to indoor air is necessary. Heterogeneous photocatalysis has been studied for its ability to oxidize, inactivating microorganisms in the air. In the present work, a reactor was assembled, where titanium dioxide (TiO2) P25 was incorporated into the inner face of polyvinyl chloride (PVC) tubes and vegetable sponges (Luffa sp.). Polyester Orthophthalic (PO) resin was used to fix the TiO2 onto the surfaces. Ultraviolet lamps (UVA) were used to activate the TiO2 catalyst to test the inactivation capacity of microorganisms, as they are economical and present high energy efficiency and long service life. The inactivation of microorganisms was evaluated in natural and artificially contaminated atmospheres. The photocatalytic reactor proved efficient in most tests in both atmospheres. In tests 1 and 2, no bacterial colony-forming units (CFUs) were found in the photocatalysis tube. In test 3, the average of 5 CFUs of fungi in the photocatalysis tube and 12.67 in the control tube was found, indicating inactivation. Therefore, this research is essential for presenting an alternative solution for indoor air treatment.