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11 result(s) for "De Paula, Joel Campos"
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Causes and effects of sampling bias on marine Western Atlantic biodiversity knowledge
Aim Knowledge gaps and sampling bias can lead to underestimations of species richness and distortions in the known distribution of species. The goal of this study is to identify potential gaps and biases in marine organisms sampling at the Western Atlantic Ocean, determine their causes and assess its effect on biodiversity metrics. We tested the potential interference of this bias with the representation of environmental conditions, potentially affecting biodiversity model predictions. Location Western Atlantic Ocean. Methods This study compiled data of marine species in online and institutional databases. The analysis of sampling effort and bias was conducted by mapping the density of records. A spatial autoregressive model (SAR) was employed to investigate the influence of accessibility as a determinant factor of the sampling bias. We tested whether the effect of the sampling bias could result from environmental bias in the samples, contrasting the environmental variables of the study area with those present in the biodiversity records. We examined the correlation between sampling effort in species richness and endemism. Results The USA has the highest number of records and density of records. There was a low correlation between the vertebrates, invertebrates and algae sample density patterns. Accessibility was identified as one of the main causes of sampling bias. The analysis of environmental bias indicated that the records do not represent all conditions present in the environment. Sampling density showed a strong relationship with endemism and a weaker relationship with species richness. Main Conclusions We have identified a strong sampling bias related to ease of access that equally affects vertebrates, invertebrates and algae, resulting in a skewed sampling of the environmental conditions where species occur. Sampling patterns differ among the groups. The intensity of sampling effort significantly impacts measures of richness and endemism, potentially undermining the accurate recognition of real biological diversity patterns.
Non-native species in reservoirs: how are we doing in Brazil?
The Brazilian Environmental Ministry (MMA) released a report in 2016 listing 163 non-native species into Brazilian inland waters. Reservoirs are among the freshwater habitats most frequently associated with the release of non-native species. Therefore, the aim of the present study was to evaluate the occurrence and distribution of the non-native species listed by the MMA, in large Brazilian reservoirs (≥ 30 km2). Further, we have tested the hypothesis that beta diversity of non-native species within reservoirs from the same basin is lower than those among reservoirs from distinct basins. A literature search was performed for 70 Brazilian reservoirs, resulting in the records of 91 non-native species. Reservoirs from the Paraná basin showed the highest number of occurrences, with 33 non-native species recorded only in the Itaipu reservoir. Beta diversity of non-native species showed higher variability among reservoirs from different basins than those within the same basin. Some basins were also distinguished by their composition of non-native species, as supported by the IndVal index. Non-native species were widespread along Brazilian reservoirs, and their distribution can be even higher than reported.
Chemodiversity of the brown algae Canistrocarpus cervicornis (Dictyotaceae, Phaeophyceae) in tropical and subtropical populations along the southwestern Atlantic coast of Brazil
Three populations of the brown seaweed Canistrocarpus cervicornis along 1800 km of the southwestern Atlantic coast were studied. Phylogenetic analysis based on the plastid and mitochondrial genes rbcL and nad1, respectively, confirmed that these populations were composed of the same taxon. Crude ethyl acetate extracts were analysed by gas chromatography coupled to a mass spectrometer (GC/MS), which revealed 13 detectable products whose fragment patterns were compatible with those expected for diterpenes. The analysis of fragment patterns identified the diterpenoid 4,7-diacetoxy-14-hydroxydolastane-1 (15), 8-diene as the major product in all the populations. Furthermore, the concentration of this diterpenoid and other products were highly variable among the three populations. However, this plasticity was not observed in sample morphology, which was generally conserved among the populations. Therefore, GC/MS enabled the detection of differences in diterpene chemodiversity within geographically distinct populations of C. cervicornis, and even though natural product abundance varied greatly, molecular markers and morphology were highly conserved.
Diterpenes from the Brown Alga Dictyota crenulata
The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I) and xeniane diterpenes (group III), thus making it a new source of potential antiviral products.
How the Ecology of Calcified Red Macroalgae is Investigated under a Chemical Approach? A Systematic Review and Bibliometric Study
Characteristics such as calcareous morphology and life cycle are used to understand the ecology of calcified rhodophytes. However, there is limited information regarding their chemical profiles and biological activities. Therefore, a systematic review (PRISMA) was conducted to assess the influence of the chemistry of calcareous rhodophytes on ecological interactions in the marine environment. The keywords used were: [\"Chemical AND [Ecology OR Interaction OR Response OR Defense OR Effect OR Cue OR Mediated OR Induce]\"] AND [\"Red Seaweed\" OR \"Red Macroalgae\" OR Rhodophy?] AND [Calcified OR Calcareous] in Science Direct, Scielo, PUBMED, Springer, Web of Science, and Scopus. Only English articles within the proposed theme were considered. Due to the low number of articles, another search was conducted with three classes and 16 genera. Finally, 67 articles were considered valid. Their titles, abstracts, and keywords were analyzed using IRaMuTeQ through factorial, hierarchical and similarity classification. Most of the studies used macroalgae thallus to evaluate chemical mediation while few tested crude extracts. Some substances were noted as sesquiterpene (6-hydroxy-isololiolide), fatty acid (heptadeca5,8,11-triene) and dibromomethane. The articles were divided into four classes: Herbivory, Competition, Settlement/Metamorphosis, and Epiphytism. Crustose calcareous algae were associated with studies of Settlement/Metamorphosis, while calcified algae were linked to herbivory. Thus, the importance of chemistry in the ecology of these algae is evident,and additional studies are needed to identify the substances responsible for ecological interactions. This study collected essential information on calcified red algae, whose diversity appears to be highly vulnerable to the harmful impacts of ongoing climate change.
Parallel adaptation of rabbit populations to myxoma virus
In the 1950s the myxoma virus was released into European rabbit populations in Australia and Europe, decimating populations and resulting in the rapid evolution of resistance. We investigated the genetic basis of resistance by comparing the exomes of rabbits collected before and after the pandemic. We found a strong pattern of parallel evolution, with selection on standing genetic variation favoring the same alleles in Australia, France, and the United Kingdom. Many of these changes occurred in immunity-related genes, supporting a polygenic basis of resistance. We experimentally validated the role of several genes in viral replication and showed that selection acting on an interferon protein has increased the protein’s antiviral effect.
A glimpse into the early origins of medieval anatomy through the oldest conserved human dissection (Western Europe, 13(th) c. A.D.)
Medieval autopsy practice is very poorly known in Western Europe, due to a lack of both descriptive medico-surgical texts and conserved dissected human remains. This period is currently considered the dark ages according to a common belief of systematic opposition of Christian religious authorities to the opening of human cadavers. The identification in a private collection of an autopsied human individual dated from the 13(th) century A.D. is an opportunity for better knowledge of such practice in this chrono-cultural context, i.e. the early origins of occidental dissections. A complete forensic anthropological procedure was carried out, completed by radiological and elemental analyses. The complete procedure of this body opening and internal organs exploration is explained, and compared with historical data about forensic and anatomical autopsies from this period. During the analysis, a red substance filling all arterial cavities, made of mercury sulfide (cinnabar) mixed with vegetal oil (oleic and palmitic acids) was identified; it was presumably used to highlight vascularization by coloring in red such vessels, and help in the preservation of the body. Of particular interest for the description of early medical and anatomical knowledge, this \"human preparation\" is the oldest known yet, and is particularly important for the fields of history of medicine, surgery and anatomical practice.
Special Anatomical pathology: A glimpse into the early origins of medieval anatomy through the oldest conserved human dissection (Western Europe, 13th c. A.D.)
Introduction: Medieval autopsy practice is very poorly known in Western Europe, due to a lack of both descriptive medico-surgical texts and conserved dissected human remains. This period is currently considered the dark ages according to a common belief of systematic opposition of Christian religious authorities to the opening of human cadavers. Material and methods: The identification in a private collection of an autopsied human individual dated from the 13th century A.D. is an opportunity for better knowledge of such practice in this chrono-cultural context, i.e. the early origins of occidental dissections. A complete forensic anthropological procedure was carried out, completed by radiological and elemental analyses. Results: The complete procedure of this body opening and internal organs exploration is explained, and compared with historical data about forensic and anatomical autopsies from this period. During the analysis, a red substance filling all arterial cavities, made of mercury sulfide (cinnabar) mixed with vegetal oil (oleic and palmitic acids) was identified; it was presumably used to highlight vascularization by coloring in red such vessels, and help in the preservation of the body. Conclusions: Of particular interest for the description of early medical and anatomical knowledge, this \"human preparation\" is the oldest known yet, and is particularly important for the fields of history of medicine, surgery and anatomical practice.