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| 5. |
- Correa, D. F., et al.
(författare)
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Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
- 2023
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 32:1, s. 49-69
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Tidskriftsartikel (refereegranskat)abstract
- Aim To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period Tree-inventory plots established between 1934 and 2019. Major taxa studied Trees with a diameter at breast height (DBH) >= 9.55 cm. Location Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types.
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- Householder, John Ethan, et al.
(författare)
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One sixth of Amazonian tree diversity is dependent on river floodplains
- 2024
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Ingår i: NATURE ECOLOGY & EVOLUTION. - 2397-334X.
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Tidskriftsartikel (refereegranskat)abstract
- Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.
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- Luize, Bruno Garcia, et al.
(författare)
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Geography and ecology shape the phylogenetic composition of Amazonian tree communities
- 2024
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Ingår i: JOURNAL OF BIOGEOGRAPHY. - 0305-0270 .- 1365-2699.
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and v & aacute;rzea forest types, the phylogenetic composition varies by geographic region, but the igap & oacute; and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R-2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R-2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
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| 8. |
- ter Steege, Hans, et al.
(författare)
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Mapping density, diversity and species-richness of the Amazon tree flora
- 2023
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Ingår i: COMMUNICATIONS BIOLOGY. - 2399-3642. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution. A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.
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| 9. |
- Nogueira, C. C., et al.
(författare)
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Atlas of Brazilian Snakes: Verified Point-Locality Maps to Mitigate the Wallacean Shortfall in a Megadiverse Snake Fauna
- 2019
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Ingår i: South American Journal of Herpetology. - : Brazilian Herpetological Society. - 1808-9798. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Accurate and detailed species distribution maps are fundamental for documenting and interpreting biological diversity. For snakes, an ecologically diverse group of reptiles, syntheses and detailed data on distribution patterns remain scarce. We present the first comprehensive collection of detailed, voucher-based, point-locality, range maps for all described and documented Brazilian snakes, with the major aim of mitigating the Wallacean shortfall and as a contribution towards a better understanding of this rich, threatened, and poorly studied megadiverse fauna. We recorded a total of 412 snake species in Brazil on the basis of an extensive and verified point-locality database of 163,498 entries and 75,681 unique records (available here as Online Supporting Information). Our results reveal previously undocumented patterns of distribution, sampling effort, richness, and endemism levels, resulting in a more objective view of snake diversity in the Neotropics. Apart from these achievements, we understand that the most relevant and enduring contribution of the present atlas is to stimulate researchers to publish corrections, additions, and new discoveries.
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| 10. |
- Ralimanana, H., et al.
(författare)
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Madagascar’s extraordinary biodiversity: Threats and opportunities
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623
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Forskningsöversikt (refereegranskat)abstract
- Madagascar’s unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar’s terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.
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| 20. |
- Azevedo, Josué, et al.
(författare)
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Museums and cradles of diversity are geographically coincident for narrowly distributed Neotropical snakes
- 2020
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Ingår i: Ecography. - : Wiley. - 0906-7590 .- 1600-0587. ; 43:2, s. 328-339
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Tidskriftsartikel (refereegranskat)abstract
- Factors driving the spatial configuration of centres of endemism have long been a topic of broad interest and debate. Due to different eco-evolutionary processes, these highly biodiverse areas may harbour different amounts of ancient and recently diverged organisms (paleo- and neo-endemism, respectively). Patterns of endemism still need to be measured at distinct phylogenetic levels for most clades and, consequently, little is known about the distribution, the age and the causes of such patterns. Here we tested for the presence of centres with high phylogenetic endemism (PE) in the highly diverse Neotropical snakes, testing the age of these patterns (paleo- or neo-endemism), and the presence of PE centres with distinct phylogenetic composition. We then tested whether PE is predicted by topography, by climate (seasonality, stability, buffering and relictualness), or biome size. We found that most areas of high PE for Neotropical snakes present a combination of both ancient and recently diverged diversity, which is distributed mostly in the Caribbean region, Central America, the Andes, the Atlantic Forest and on scattered highlands in central Brazil. Turnover of lineages is higher across Central America, resulting in more phylogenetically distinct PE centres compared to South America, which presents a more phylogenetically uniform snake fauna. Finally, we found that elevational range (topographic roughness) is the main predictor of PE, especially for paleo-endemism, whereas low paleo-endemism levels coincide with areas of high climatic seasonality. Our study highlights the importance of mountain systems to both ancient and recent narrowly distributed diversity. Mountains are both museums and cradles of snake diversity in the Neotropics, which has important implications for conservation in this region.
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| 25. |
- Durigon, Daniele C., et al.
(författare)
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The influence of thioether-substituted ligands in dicopper(II) complexes : Enhancing oxidation and biological activities
- 2024
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Ingår i: Journal of Inorganic Biochemistry. - 0162-0134. ; 256
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes the synthesis, structural analysis, as well as the magnetic and spectroscopic characterizations of three new dicopper(II) complexes with dinucleating phenol-based ligands containing different thioether donor substituents: aromatic (1), aliphatic (2) or thiophene (3). Temperature-dependent magnetometry reveals the presence of antiferromagnetic coupling for 1 and 3 (J = −2.27 cm−1 and -5.01 cm−1, respectively, H = -2JS1S2) and ferromagnetic coupling for 2 (J = 5.72 cm−1). Broken symmetry DFT calculations attribute this behavior to a major contribution from the dz2 orbitals for 1 and 3, and from the dx2-y2 orbitals for 2, along with the p orbitals of the oxygens. The bioinspired catalytic activities of these complexes related to catechol oxidase were studied using 3,5-di-tert-butylcatechol as substrate. The order of catalytic rates for the substrate oxidation follows the trend 1 > 2 > 3 with kcat of (90.79 ± 2.90) × 10−3 for 1, (64.21 ± 0.99) × 10−3 for 2 and (14.20 ± 0.32) × 10−3 s−1 for 3. The complexes also cleave DNA through an oxidative mechanism with minor-groove preference, as indicated by experimental and molecular docking assays. Antimicrobial potential of these highly active complexes has shown that 3 inhibits both Staphylococcus aureus bacterium and Epidermophyton floccosum fungus. Notably, the complexes were found to be nontoxic to normal cells but exhibited cytotoxicity against epidermoid carcinoma cells, surpassing the activity of the metallodrug cisplatin. This research shows the multifaceted properties of these complexes, making them promising candidates for various applications in catalysis, nucleic acids research, and antimicrobial activities.
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| 26. |
- Guedes, Thaís, et al.
(författare)
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Patterns, biases and prospects in the distribution and diversity of Neotropical snakes
- 2018
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 27:1, s. 14-21
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Tidskriftsartikel (refereegranskat)abstract
- Motivation: We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. Main types of variables contained: We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Spatial location and grain: Neotropics, Behrmann projection equivalent to 1 degrees x 1 degrees. Results: The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. Main conclusions: The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.
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| 27. |
- Stephens, Lucas, et al.
(författare)
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Archaeological assessment reveals Earth’s early transformation through land use
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 365:6456, s. 897-902
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Tidskriftsartikel (refereegranskat)abstract
- Humans began to leave lasting impacts on Earth’s surface starting 10,000 to 8000 years ago. Through a synthetic collaboration with archaeologists around the globe, Stephens et al. compiled a comprehensive picture of the trajectory of human land use worldwide during the Holocene (see the Perspective by Roberts). Hunter-gatherers, farmers, and pastoralists transformed the face of Earth earlier and to a greater extent than has been widely appreciated, a transformation that was essentially global by 3000 years before the present.Science, this issue p. 897; see also p. 865Environmentally transformative human use of land accelerated with the emergence of agriculture, but the extent, trajectory, and implications of these early changes are not well understood. An empirical global assessment of land use from 10,000 years before the present (yr B.P.) to 1850 CE reveals a planet largely transformed by hunter-gatherers, farmers, and pastoralists by 3000 years ago, considerably earlier than the dates in the land-use reconstructions commonly used by Earth scientists. Synthesis of knowledge contributed by more than 250 archaeologists highlighted gaps in archaeological expertise and data quality, which peaked for 2000 yr B.P. and in traditionally studied and wealthier regions. Archaeological reconstruction of global land-use history illuminates the deep roots of Earth’s transformation and challenges the emerging Anthropocene paradigm that large-scale anthropogenic global environmental change is mostly a recent phenomenon.
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| 28. |
- Antonelli, Alexandre, 1978, et al.
(författare)
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Madagascar's extraordinary biodiversity : Evolution, distribution, and use
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623, s. 962-
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Tidskriftsartikel (refereegranskat)abstract
- Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique " living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.
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| 29. |
- Carrasco, Marta, et al.
(författare)
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Probing the Azaaurone Scaffold against the Hepatic and Erythrocytic Stages of Malaria Parasites
- 2016
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Ingår i: Chemmedchem. - : Wiley. - 1860-7179. ; 11:19, s. 2194-2204
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Tidskriftsartikel (refereegranskat)abstract
- The potential of azaaurones as dual-stage antimalarial agents was investigated by assessing the effect of a small library of azaaurones on the inhibition of liver and intraerythrocytic lifecycle stages of the malaria parasite. The whole series was screened against the blood stage of a chloroquine-resistant Plasmodium falciparum strain and the liver stage of P.berghei, yielding compounds with dual-stage activity and sub-micromolar potency against erythrocytic parasites. Studies with genetically modified parasites, using a phenotypic assay based on the P.falciparum Dd2-ScDHODH line, which expresses yeast dihydroorotate dehydrogenase (DHODH), showed that one of the azaaurone derivatives has the potential to inhibit the parasite mitochondrial electron-transport chain. The global urgency in finding new therapies for malaria, especially against the underexplored liver stage, associated with chemical tractability of azaaurones, warrants further development of this chemotype. Overall, these results emphasize the azaaurone chemotype as a promising scaffold for dual-stage antimalarials.
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| 32. |
- Bernal, Ximena E., et al.
(författare)
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Empowering Latina scientists
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 363:6429, s. 825-826
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 33. |
- Entiauspe-Neto, O. M., et al.
(författare)
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Unveiling an enigma from the Cerrado: taxonomic revision of two sympatric species of Apostolepis Cope, 1862 (Dipsadidae: Xenodontinae: Elapomorphini) from central Brazil
- 2022
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Ingår i: European Journal of Taxonomy. - : Museum National D'Histoire Naturelle. - 2118-9773. ; 817, s. 143-182
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Tidskriftsartikel (refereegranskat)abstract
- Apostolepis albicollaris and A. cerradoensis are two Elapomorphini snake species, described within a short timespan, from the Cerrado of central Brazil. In their brief descriptions, these two species were diagnosed from congeners largely based on highly variable external morphological characters. Interestingly enough, A. cerradoensis has remained known based on a single specimen since its description. Here, we present a reanalysis of both type specimens, as well as a careful examination of a large series of specimens formerly assigned to these species, based on the comparison of internal and external morphology. We conclude that both species are synonymous, providing evidence for the recognition of A. cerradoensis as a junior synonym of A. albicollaris. Furthermore, an account of its updated diagnosis, morphological variation, geographic distribution, hemipenial morphology, phylogenetic relationships and an osteological description are also provided. We also discuss its conservation status, suggesting that the species is under threat and qualifies to be listed as Vulnerable (VU ab(iii)), considering its rarity, small geographic range, and persistent environmental threats.
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- Herrera-Luis, E, et al.
(författare)
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Admixture mapping of severe asthma exacerbations in Hispanic/Latino children and youth
- 2023
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Ingår i: Thorax. - : BMJ. - 1468-3296 .- 0040-6376. ; 78:3, s. 233-241
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Tidskriftsartikel (refereegranskat)abstract
- In the USA, genetically admixed populations have the highest asthma prevalence and severe asthma exacerbations rates. This could be explained not only by environmental factors but also by genetic variants that exert ethnic-specific effects. However, no admixture mapping has been performed for severe asthma exacerbations.ObjectiveWe sought to identify genetic variants associated with severe asthma exacerbations in Hispanic/Latino subgroups by means of admixture mapping analyses and fine mapping, and to assess their transferability to other populations and potential functional roles.MethodsWe performed an admixture mapping in 1124 Puerto Rican and 625 Mexican American children with asthma. Fine-mapping of the significant peaks was performed via allelic testing of common and rare variants. We performed replication across Hispanic/Latino subgroups, and the transferability to non-Hispanic/Latino populations was assessed in 1001 African Americans, 1250 Singaporeans and 941 Europeans with asthma. The effects of the variants on gene expression and DNA methylation from whole blood were also evaluated in participants with asthma and in silico with data obtained through public databases.ResultsGenomewide significant associations of Indigenous American ancestry with severe asthma exacerbations were found at 5q32 in Mexican Americans as well as at 13q13-q13.2 and 3p13 in Puerto Ricans. The single nucleotide polymorphism (SNP) rs1144986 (C5orf46) showed consistent effects for severe asthma exacerbations across Hispanic/Latino subgroups, but it was not validated in non-Hispanics/Latinos. This SNP was associated withDPYSL3DNA methylation andSCGB3A2gene expression levels.ConclusionsAdmixture mapping study of asthma exacerbations revealed a novel locus that exhibited Hispanic/Latino-specific effects and regulatedDPYSL3andSCGB3A2.
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| 36. |
- Neckel, Itamar T., et al.
(författare)
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Unveiling Center-Type Topological Defects on Rosettes of Lead Zirconate Titanate Associated to Oxygen Vacancies
- 2021
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Ingår i: Annalen der Physik. - : Wiley. - 0003-3804 .- 1521-3889.
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the formation of topological defects in ferroelectric materials can provide access to their unusual physics, invaluable for possible applications of domain engineering in nanoelectronics. The present study shows the spontaneous formation of center-type topological defects in lead zirconate titanate (PZT) films, characterized by a strong in-plane radial electromechanical response on rosette-like structures, as revealed by piezoelectric response force microscopy. Multi-modal electron and X-ray based techniques provide a comprehensive set of tools for delving at atomic scale the local chemistry, electronic, and crystalline structures. The elemental surface-sensitivity of soft X-ray absorption shows chemical segregation and drastic changes in the titanium electronic structure, which have been associated to oxygen vacancies, leading to a mechanism that describe the polarization symmetry on the rosettes. X-ray nanofluorescence experiments revealed titanium segregation, corroborating with the absorption and low energy electron microscopy images. Taking advantage of a nanobeam, 2D nanodiffraction maps probed the complex microstructure of the domains, revealing its mosaicity and lattice strain at the nanoscale. This study highlights a complex topological structure and provides, by the simultaneous application of a set of analytical tools, a broad comprehension of the formation of center-type ferroelectric topological defects in PZT.
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| 37. |
- Duque, B. R., et al.
(författare)
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Venomous snakes of medical importance in the Brazilian state of Rio de Janeiro: habitat and taxonomy against ophidism
- 2023
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Ingår i: Brazilian journal of biology = Revista brasleira de biologia. - 1678-4375. ; 83
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Tidskriftsartikel (refereegranskat)abstract
- Snakebite envenoming is a major global health problem that kills or disables half a million people in the world's poorest countries. Identifying the biting snake and its habitat use is key to understanding snakebite eco-epidemiology and optimizing its clinical management. To prevent and combat the neglected snakebite disease, we characterize the morphology, geographic distribution, habitat use, and snakebites of medically important venomous snakes in the state of Rio de Janeiro (Brazil). Despite Philodryas spp. not being considered of medical importance by the Brazilian Ministry of Health, we also explore their data once the bites may require medical intervention, may cause death, and their consequences are underestimated. Methods: We assessed taxonomy and geographic data from specimens housed in scientific collections, the literature, and the Notifiable Diseases Information System. Our data revealed fragility in the morphological characters recommended to distinguish Bothrops jararaca from B. jararacussu, identify the subspecies of Crotalus durissus and distinguish the species of Philodryas. To help identify these species, we present an identification key to the venomous snake species from Rio de Janeiro based on the morphological data collected. We record the genera Bothrops and Micrurus in all mesoregions of the state. Here, we provide the first record of C. durissus in the Serrana region, supporting the hypothesis of geographic expansion of the species in the state. The crotalic antivenom must not be missing in Médio Paraíba, Centro-Sul Fluminense, and Serrana, where the rattlesnake C. durissus occurs. Bothrops bilineatus and Lachesis muta have historical records presented for the first time herein. However, these species are likely endangered or extinct in the state. There were 7,483 snakebites reported between 2001 and 2019, with an annual average of 393.8 cases. The Bothrops genus is responsible for the majority of accidents. The highest number of cases occurred in the Serrana region, the largest pole of family agriculture in Rio de Janeiro. We improve the identification of venomous snake species, better delimit their distribution, and update the number of cases of snakebites, thus providing greater precision in the attention to this problem in Rio de Janeiro. We emphasize the importance of clinical studies to test using bothropic-crotalic antivenom and heparin in all mesoregions to treat B. jararacussu envenomation; and mechanical ventilation, atropine, and anticholinesterases in the emergency health centers in the Metropolitana and Norte Fluminense regions due to the occurrence of the coral M. lemniscatus in these areas.
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| 38. |
- Entiauspe-Neto, O. M., et al.
(författare)
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Redescription of Apostolepis ambiniger (Peters, 1869) (Serpentes: Dipsadidae: Elapomorphini)
- 2021
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Ingår i: Vertebrate Zoology. - : Pensoft Publishers. - 1864-5755 .- 2625-8498. ; 71, s. 231-251
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Tidskriftsartikel (refereegranskat)abstract
- Apostolepis is a diverse genus of dipsadid snakes, currently comprising 34 species occurring in most cis-Andean South America. The taxonomy of the group is highly unstable. Upon discovering its type series, we redescribe the rare species A. ambiniger (Peters, 1869) and provide an account of its geographic distribution and morphological variation in pholidosis, osteology, and hemipenial characters. We also discuss some aspects of the taxonomy of Apostolepis.
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| 39. |
- Entiauspe-Neto, O. M., et al.
(författare)
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Taxonomic status of Apostolepis tertulianobeui Lema, 2004 based on an integrative revision of Apostolepis assimilis (Reinhardt, 1861) (Serpentes: Dipsadidae)
- 2021
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Ingår i: Zoologischer Anzeiger. - : Elsevier BV. - 0044-5231. ; 291, s. 123-138
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Tidskriftsartikel (refereegranskat)abstract
- Apostolepis is a diverse Dipsadid snake genus, with 35 known species, inhabiting most of South America at east of the Andes. In this study, we redescribe Apostolepis assimilis Reinhardt, 1861, and evaluate the taxonomic status of a controversial taxon, Apostolepis tertulianobeui, described based on a single specimen from an unknown locality of Minas Gerais state, southeastern Brazil. A careful reanalysis of the type specimen and additional material provides compelling evidence for the synonymy of A. tertulianobeui with A. assimilis. We also provide comments on the taxonomy of Apostolepis, osteological and hemipenial descriptions, and a species distribution modelling for A. assimilis. (c) 2021 Published by Elsevier GmbH.
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| 40. |
- Fahimi, A., et al.
(författare)
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Poultry litter ash characterisation and recovery
- 2020
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Ingår i: Waste Management. - : Elsevier Ltd. - 0956-053X .- 1879-2456. ; 111, s. 10-21
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports a complete characterisation of poultry litter ash and its potential use as a heavy metal stabiliser. We propose a novel approach, in which the ashes deriving from municipal solid waste incineration (MSWI) are combined with poultry litter ash, rather than with coal combustion flue gas desulfurisation (FGD) residues. Heavy metals stabilisation was demonstrated by comparing the elemental concentrations in the leaching solutions of the starting raw and stabilised materials: leachable Pb and Zn showed a reduced solubility. The characterisation was conducted by total reflection X-ray fluorescence (TXRF), X-ray diffraction (XRD), micro-Raman spectroscopy and scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDX). The results showed that the poultry litter ash was Ca-, P-, K- and S-rich (>29 g/kg). It contained amorphous materials (i.e. fly ash economiser (FAECO) 73% and fly ash cyclone (FACYC) 61%) and soluble phases (e.g. arkanite and sylvite; up to 13% FAECO and 28% FACYC), as well as resilient crystalline (up to 2% of FAECO and FACYC) and amorphous phases (e.g. hydroxyapatite). After two months, the Pb and Zn concentrations in the leachate solutions were below the limit set by the European regulations for waste disposal (<0.2 mg/L and 1.5 mg/L, respectively). We propose a mechanism for the heavy metals stabilisation based on the carbonation process and high amounts of P, Ca and reactive amorphous phases. In conclusion, it is demonstrated that poultry litter ash can be an effective secondary source of heavy metals, allowing their immobilisation through P- and Ca-based reactive amorphous phases.
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| 41. |
- Gonzalez, R. C., et al.
(författare)
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Back in time to unlock the future: tracing the type-specimens of Corallus hortulana (Linnaeus, 1758) (Serpentes: Boidae), with designation of a lectotype for the Amazon tree boa
- 2021
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Ingår i: Zootaxa. - : Magnolia Press. - 1175-5326 .- 1175-5334. ; 4941:2, s. 259-270
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Tidskriftsartikel (refereegranskat)abstract
- Corallus hortulana presents a large array of tones and color pattern variability throughout its distribution (= polychromatism), which trigged the description of several taxa now considered to be primary synonyms. Linnaeus described two of these (Boa enydris and Boa hortulana) on the same page of the 10th Edition of the Systema Naturae. However, both names had been widely used in literature almost in an optional way, until their formal synonymization more than two centuries after the original description. Additionally, the type specimen of Boa hortulana was reported as missing since the late 19th century. These two factors may have enabled the unjustified switched association of types, which was perpetuated in the literature to the present day. Our main goals here were to trace the correct type specimens for each species through a literature review and specimen examination, and to amend the switched association of type material. We found two specimens in the collection of the Uppsala University that are unmistakably associated with Boa hortulana. Herein we designate one of them as its lectotype in order to promote nomenclatural stability considering its huge phenotypic variability and the future possibility of eventually splitting the species.
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| 42. |
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| 43. |
- Soares, C. J., et al.
(författare)
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Characterisation of Apatites as Potential Uranium Reference Materials for Fission-track Dating by LA-ICP-MS
- 2015
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Ingår i: Geostandards and Geoanalytical Research. - 1639-4488. ; 39:3, s. 305-313
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Tidskriftsartikel (refereegranskat)abstract
- k crystal (6.9gg(-1)U). The relative standard deviation (1 RSD) of the U concentration determined by ID-ICP-MS of both apatite crystals was 1.5%, whereas 1 RSD for the We report homogeneity tests on large natural apatite crystals to evaluate their potential as U reference materials for apatite fission-track (AFT) thermochronology by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The homogeneity tests include the measurements of major element concentrations by electron probe microanalysis (EPMA), whereas for U concentration, isotope dilution (ID) ICP-MS and laser ablation (LA) ICP-MS were employed. Two apatite crystals are potential reference materials for LA-ICP-MS analysis: a 1cm(3) fraction of a Durango crystal (7.5gg(-1)U) and a 1cm(3) Mud TanLA-ICP-MS results was better than 4%, providing sufficient homogeneity for fission-track dating. The results on the U homogeneity for two different apatite samples are an important step towards establishing in situ dating routines for AFT analysis by LA-ICP-MS. Nous restituons des tests d'homogeneite sur des grands cristaux d'apatite naturelle afin d'evaluer leur potentiel en tant que materiaux de reference pour l'U en vue d'une application dans le domaine de la thermochronologie par traces de fission sur apatite (AFT) par spectrometrie de masse a plasma induit couplee a l'ablation laser (LA-ICP-MS). Les tests d'homogeneite incluent des mesures des concentrations en elements majeurs par microsonde electronique (EPMA), alors que pour la concentration en U, la dilution isotopique (ID) ainsi que l'ablation laser (LA) ICP-MS ont ete employees. Deux cristaux d'apatite sont des materiaux de reference possibles pour les analyses LA-ICP-MS: une fraction d'1 cm(3) d'un cristal de Durango (7,5 mu gg(-1)U) et un cristal d'1cm(3) de Mud Tank (6,9 mu gg(-1)U). L'ecart type relatif (1RSD) de la concentration en U determinee par ID-ICP-MS des deux cristaux d'apatite est 1,5%, tandis que celui pour les resultats LA-ICP-MS est inferieur a 4%, offrant ainsi une homogeneite suffisante pour les datations par la methode des traces de fission sur apatite. Les resultats concernant l'homogeneite de l'U pour deux echantillons differents d'apatite sont une etape importante vers la possibilite d'envisager des datations AFT in situ en routine par LA-ICP-MS.
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| 44. |
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