Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
PeerJ ; 12: e16712, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560463

RESUMO

Biotic and abiotic factors play a crucial role in determining the distribution of species. These factors dictate the conditions that must be met for a species to thrive in a particular area. Sister species that present some degree of niche overlap can shed light on how they are distributed and coexist in their environment. This study aims to investigate the geographical distribution and ecological niche of the sister species of snake-necked turtles Hydromedusa maximiliani and H. tectifera. By analyzing their niche overlap, we aim to obtain a better understanding of how these two species coexist and which variables are determining their occurences. We applied species distribution modeling and compared the niches using the niche equivalence and similarity tests. Our findings show that the distribution of H. maximiliani is most influenced by temperature seasonality and isothermality, while H. tectifera is most affected by the temperature seasonality, precipitation of warmest quarter and mean diurnal range. In addition, our results suggest that the niche expressed by H. maximiliani retained ecological characteristics that can accurately predict the H. tectifera distribution, but the inverse is not true. In this sense, differences are not solely due to the geographic availability of environmental conditions but can reflect niche restrictions, such as competition.


Assuntos
Tartarugas , Animais , Ecossistema , Temperatura
2.
Artigo em Inglês | MEDLINE | ID: mdl-38374940

RESUMO

The skin of anuran species is a protective barrier against predators and pathogens, showing also chemical defense by substances that represent a potential source for bioactive substances. This review describes the current chemical and biological knowledge from the skin secretions of Leptodactylidae species, one of the most diverse neotropical frog families. These skin secretions reveal a variety of substances such as amines (12), neuropeptides (16), and antimicrobial peptides (72). The amines include histamine and its methylated derivatives, tryptamine derivatives and quaternary amines. The peptides of Leptodactylidae species show molecular weight up to 3364 Da and ocellatins are the most reported. The peptides exhibit commonly glycine (G) or glycine-valine (GV) as C-terminal amino acids, and the most common N-terminal amino acids are glutamic acid (E), lysine (K), and valine (V). The substances from Leptodactylidae species have been evaluated against pathogenic microorganisms, particularly Escherichia coli and Staphylococcus aureus, and the most active peptides showed MIC of 1-15 µM. Furthermore, some compounds showed also pharmacological properties such as immunomodulation, treatment of degenerative diseases, anticancer, and antioxidant. Currently, only 9% of the species in this family have been properly studied, highlighting a large number of unstudied species such as an entire subfamily (Paratelmatobiinae). The ecological context, functions, and evolution of peptides and amines in this family are poorly understood and represent a large field for further exploration.

4.
Nature ; 622(7982): 308-314, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794184

RESUMO

Systematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.


Assuntos
Anfíbios , Mudança Climática , Ecossistema , Espécies em Perigo de Extinção , Animais , Anfíbios/classificação , Biodiversidade , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Risco , Urodelos/classificação
5.
Ecol Lett ; 26(6): 869-882, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36967645

RESUMO

Biodiversity loss not only implies the loss of species but also entails losses in other dimensions of biodiversity, such as functional, phylogenetic and interaction diversity. Yet, each of those facets of biodiversity may respond differently to extinctions. Here, we examine how extinction, driven by climate and land-use changes may affect those different facets of diversity by combining empirical data on anuran-prey interaction networks, species distribution modelling and extinction simulations in assemblages representing four Neotropical ecoregions. We found a mismatch in the response of functional, phylogenetic and interaction diversity to extinction. In spite of high network robustness to extinction, the effects on interaction diversity were stronger than those on phylogenetic and functional diversity, declining linearly with species loss. Although it is often assumed that interaction patterns are reflected by functional diversity, assessing species interactions may be necessary to understand how species loss translates into the loss of ecosystem functions.


Assuntos
Biodiversidade , Ecossistema , Animais , Filogenia , Clima , Anuros
6.
J Anim Ecol ; 92(2): 324-337, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36059124

RESUMO

Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections. For some animals, the inspection of preserved specimens can reveal the scars of past antagonistic encounters, such as predation attempts. A common defensive behaviour that leaves scars on animals is autotomy, the loss of a body appendage to escape predation. By knowing the collection site of preserved specimens, it is possible to assess the influence of organismal biology and the surrounding environment in the occurrence of autotomy. We gathered data on tail loss for 8189 preserved specimens of 33 snake and 11 amphisbaenian species to investigate biological and environmental correlates of autotomy in reptiles. We applied generalized linear mixed effect models to evaluate whether body size, sex, life-stage, habitat use, activity pattern, biome, tropicality, temperature and precipitation affect the probability of tail loss in limbless reptiles. We observed autotomy in 23.6% of examined specimens, with 18.7% of amphisbaenian and 33.4% of snake specimens showing tail loss. The probability of tail loss did not differ between snakes and amphisbaenians, but it was higher among large-sized specimens, particularly in adults and females. Chance of tail loss was higher for diurnal and arboreal species, and among specimens collected in warmer regions, but it was unaffected by biome, precipitation, and tropicality. Autotomy in limbless reptiles was affected by size-dependent factors that interplay with ontogeny and sexual dimorphism, although size-independent effects of life-stage and sex also shaped behavioural responses to predators. The increase in probability of tail loss with verticality and diurnality suggests a risk-balance mechanism between species habitat use and activity pattern. Although autotomy is more likely in warmer regions, it seems unrelated to seasonal differences in snakes and amphisbaenians activity. Our findings reveal several processes related to predator-prey interactions involving limbless reptiles, demonstrating the importance of scientific collections to unveil ecological mechanisms at different spatio-temporal scales.


Assuntos
Lagartos , Feminino , Animais , Lagartos/fisiologia , Cauda/fisiologia , Comportamento Predatório , Cicatriz , Ecossistema
7.
An Acad Bras Cienc ; 94(4): e20200825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36477987

RESUMO

We evaluated the extent of intraspecific and interspecific genetic distances and the effectiveness of predefined threshold values using the main genes for estimates of biodiversity and specimens' identification in anurans. Partial sequences of the mitochondrial genes for small (12S) and large (16S) ribosomal subunits, cytochrome c oxidase subunit I (COI) and Cytochrome b (Cytb) of the family Hylidae were downloaded from GenBank and curated for length, coverage, and potential contaminations. We performed analyses for all sequences of each gene and the same species present in these datasets by distance and tree (monophyly)-based evaluations. We also evaluated the ability to identify specimens using these datasets applying "nearest neighbor" (NN), "best close match" (BCM) and "BOLD ID" tests. Genetic distance thresholds were generated by the function 'threshVal' and "localMinima" from SPIDER package and traditional threshold values (1%, 3%, 6% and 10%) were also evaluated. Coding genes, especially COI, had a better identification capacity than non-coding genes on barcoding gap and monophyly analysis and NN, BCM, BOLD ID tests. Considering the multiple factors involved in global DNA barcoding evaluations, we present a critical assessment of the use of these genes for biodiversity estimation and specimens' identification in anurans (e.g. hylids).


Assuntos
Anuros , Citocromos b , Animais , RNA Ribossômico 16S/genética , Código de Barras de DNA Taxonômico
8.
Ecol Evol ; 12(11): e9503, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36407904

RESUMO

Macroecological studies describe large-scale diversity patterns through analyses of species distribution patterns and allows us to elucidate how species differing in ecology, physical requirements, and life histories are distributed in a multidimensional space. These patterns of distributions can be explained by vegetation, and climatic factors, and are determined by historical and current factors. The continuous accumulation of information on the distribution patterns of species is essential to understand the history and evolution of the biota. In this study, we aimed to identify functional and evolutionary drivers that explain the geographic patterns of vertical stratification. We compiled morphological, ecological, and distribution data of 140 species of Chacoan snakes and constructed null models to map their geographic pattern. We used a range of environmental variables to assess which drivers are influencing these biogeographic patterns. Lastly, we used evolutionary data to build the first map of the phylogenetic regions of Chacoan snakes. We found a latitudinal pattern, with a marked verticality in the snake assemblies in the Chaco. Verticality and long-tailed species richness increased in areas with high stratified habitats and stable temperature. Fossoriality is driven mainly by soil conditions, especially soils with fewer sand particles and less stratified habitat. Phylogenetic regions in the Chaco showed a marked latitudinal pattern, like that observed in the geographic pattern of verticality. The distribution pattern of Chacoan snakes also reflects their evolutionary history, with a marked phylogenetic regionalization.

9.
Zootaxa ; 5155(4): 564-580, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-36095567

RESUMO

The genus Crossodactylus has taxonomic problems due to the difficulty in properly identifying some populations to the species level. The deficient species diagnosis rises mostly due to high intraspecific variation and lack of information on topotypes. Crossodactylus timbuhy was described based only on external morphology of preserved adult specimens. Based on topotypic specimens, we provide further information on C. timbuhy regarding color in life (both adult and larvae), tadpole external morphology, vocal repertoire, natural history, and geographic distribution. The species identification was confirmed through comparison to the type series, 16S rRNA analysis, and bioacoustics. Crossodactylus timbuhy vocalizes during daylight along shallow slow-flowing streams. The advertisement call has ascendant amplitude modulation, duration of 2.18.4 s, 2375 pulsed notes, and peak frequency of 3.64.8 kHz. Our report on male unilateral sac inflation is the first within Crossodactylus. Although overall tadpole external morphology and coloration resemble other species of hylodids, we report ventral depression and golden iridophores also for the first time within Crossodactylus. Adult males display five antipredator mechanisms (interrupt calling, escape, aggression, posture, and aposematism). Finally, we restrict its geographic distribution to the Municipality of Santa Teresa, State of Esprito Santo, Southeastern Brazil.


Assuntos
Anuros , Rios , Animais , Larva/anatomia & histologia , Masculino , RNA Ribossômico 16S
10.
Rev. baiana saúde pública ; 46(1): 294-303, 20220707.
Artigo em Português | LILACS | ID: biblio-1379959

RESUMO

A pandemia pelo Covid-19¹ levou o Brasil ao maior colapso sanitário-hospitalar de sua história. O Programa Mais Médicos (PMM) prevê a qualificação profissional dos médicos, além de contar com as instituições públicas de educação superior por meio da supervisão acadêmica2. Contudo, a situação pandêmica restringiu as visitas de supervisão, as quais passaram a ser realizadas virtualmente. Com isto, este artigo busca conhecer o olhar dos supervisores acadêmicos na atuação dentro do PMMB, no contexto da pandemia do Covid-19, a luz das fragilidades e potencialidades no que tange à atuação na atenção básica. Trata-se de um relato de experiência realizado com base nos relatórios de acompanhamento do processo de supervisão acadêmica. Foram realizados nos momentos de avaliação das supervisões, elaborado pela tutoria, com os 16 supervisores, entre 2020 e 2021. Como resultado, notamos a indisponibilidade de internet estável nas Unidades Básicas de Saúde (UBS), perda da vinculação, devido a distância física não propiciar o fortalecimento do vínculo com os gestores das secretarias de saúde, dificuldades no manejo clínico das infecções respiratórias, a realização de diagnósticos diferenciais, a gestão da demanda reprimida e prejuízos frente à saúde mental dos profissionais. Portanto, o uso de ferramentas virtuais para manter o vínculo com seus supervisionados foi a estratégia mais efetiva nesse período de distanciamento social. A pandemia pelo Covid-19 trouxe desafios para os profissionais médicos, porém mesmo diante das fragilidades apontadas, à presença do supervisor acadêmico, se possibilitou a educação permanente, diante de uma doença nova e com atualizações de propedêutica recorrentes, bem como o apoio organizacional e ético.


The Covid-19 pandemic resulted in the biggest health system collapse in Brazil's history. Within the Mais Médicos Program (PMM), professional qualification by academic supervision relied on public higher education institutions, activity that became restricted to virtual meetings due to the pandemic situation. Given this context, this experience report investigates how academic supervisors evaluate their performance within the PMM during the Covid-19 pandemic, focusing on the weaknesses and potentialities in primary health care. Data were collected from the academic supervision monitoring reports on tutoring evaluation carried out by 16 supervisors, between 2020 and 2021. Poor internet connection (instability, loss of connection) in the UBS hinders strengthening the bond between physicians and health management. Results point to difficulties in the clinical management of respiratory infections, in performing differential diagnoses, in managing pent-up demand and mental health issues. During social distancing, the use of virtual tools was the most effective strategy to maintain the academic bonds. Notwithstanding the challenges brought and weaknesses revealed by the pandemic, the academic supervision enabled permanent education in the face of a new disease and recurrent propaedeutic updates, as well as organizational and ethical support.


La pandemia del COVID-19¹ llevó a Brasil al mayor colapso sanitario hospitalario de su historia. El Programa Más Médicos (PMM) prevé la calificación profesional de los médicos y de las instituciones  de educación superior públicas, a través de la supervisión académica. Sin embargo, la situación pandémica ha restringido las visitas de supervisión, que ahora se han realizado de manera virtual. Ante lo anterior, este artículo tiene como objetivo conocer la perspectiva de los supervisores académicos en el desempeño del PMM en el contexto de la pandemia del COVID-19, a la luz de las debilidades  y potencialidades en cuanto al desempeño en la atención primaria. Este es un informe de experiencia basado en los informes de seguimiento del proceso de supervisión académica, realizado por la tutoría en los momentos de evaluación de las supervisiones, en la que participaron 16 supervisores en el período entre 2020 y 2021. La indisponibilidad de internet estable en la Unidad Básica de Salud (UBS) y la pérdida de conexión por distanciamiento físico no brindan el fortalecimiento del vínculo con los directivos de los departamentos de salud. Se observaron dificultades en el manejo clínico de las infecciones respiratorias, realización de diagnósticos diferenciales, manejo de la demanda acumulada y problemas de salud mental entre los profesionales. Se concluye que el uso de herramientas virtuales para mantener el vínculo con sus supervisados fue la estrategia más efectiva en este período de distanciamiento social. La pandemia del COVID-19 ha generado desafíos para los profesionales médicos. Sin embargo, en estas debilidades, la presencia del supervisor académico posibilitó  la educación permanente frente a una nueva enfermedad y con actualizaciones propedéuticas recurrentes, además de apoyo organizacional y ético.


Assuntos
Atenção Primária à Saúde , Monitoramento Ambiental , Educação Médica Continuada , Consórcios de Saúde , Pandemias , COVID-19
11.
PLoS One ; 17(4): e0266710, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35390108

RESUMO

Drosophila saltans group belongs to the subgenus Sophophora (family Drosophilidae), and it is subdivided into five subgroups, with 23 species. The species in this group are widely distributed in the Americas, primarily in the Neotropics. In the literature, the phylogenetic reconstruction of this group has been performed with various markers, but many inconsistencies remain. Here, we present a phylogenetic reconstruction of the saltans group with a greater number of species, 16 species, which is the most complete to date for the saltans group and includes all subgroups, in a combined analysis with morphological and molecular markers. We incorporated 48 morphological characters of male terminalia, the highest number used to date, and molecular markers based on mitochondrial genes COI and COII. Based on the results, which have recovered the five subgroups as distinct lineages, we propose a new hypothesis regarding the phylogenetic relationships among the subgroups of the saltans group. The relationships of the species within the sturtevanti and elliptica subgroups were well supported. The saltans subgroup showed several polytomies, but the relationship between the sibling species D. austrosaltans and D. saltans and their close relation with D. nigrosaltans were well supported in the molecular and total evidence analyses. The morphological analysis additionally supported the formation of the clade D. nigrosaltans-D. pseudosaltans. The observed polytomies may represent synchronous radiations or have resulted from speciation rates that have been too fast relative to the pace of substitution accumulation.


Assuntos
Drosophila , Drosophilidae , Animais , Drosophila/anatomia & histologia , Drosophilidae/genética , Genes Mitocondriais , Masculino , Filogenia
12.
Ecol Evol ; 12(4): e8754, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35386873

RESUMO

The Amazonia and the Atlantic Forest, separated by the diagonal of open formations, are two ecoregions that comprise the most diverse tropical forests in the world. The Sphaenorhynchini tribe is among the few tribes of anurans that occur in both rainforests, and their historical biogeographic have never been proposed. In this study, we infer a dated phylogeny for the species of the Sphaenorhynchini and we reconstructed the biogeographic history describing the diversification chronology, and possible patterns of dispersion and vicariance, providing information about how orogeny, forest dynamics and allopatric speciation affected their evolution in South America. We provided a dated phylogeny and biogeography study for the Sphaenorhynchini tribe using mitochondrial and nuclear genes. We analyzed 41 samples to estimate the ancestral areas using biogeographical analysis based on the estimated divergence times and the current geographical ranges of the species of Sphaenorhynchini. We recovered three characteristic clades that we recognize as groups of species (S. lacteus, S. planicola, and S. platycephalus groups), with S. carneus and G. pauloalvini being the sister taxa of all other species from the tribe. We found that the diversification of the tribe lineages coincided with the main climatic and geological factors that shaped the Neotropical landscape during the Cenozoic. The most recent common ancestor of the Sphaenorhynchini species emerged in the North of the Atlantic Forest and migrated to the Amazonia in different dispersion events that occurred during the connections between these ecoregions. This is the first large-scale study to include an almost complete calibrated phylogeny of Sphaenorhynchini, presenting important information about the evolution and diversification of the tribe. Overall, we suggest that biogeographic historical of Sphaenorhynchini have resulted from a combination of repeated range expansion and contraction cycles concurrent with climate fluctuations and dispersal events between the Atlantic Forest and Amazonia.

13.
Ecology ; 103(8): e3716, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35388458

RESUMO

Space and time promote variation in network structure by affecting the likelihood of potential interactions. However, little is known about the relative roles of ecological and biogeographical processes in determining how species interactions vary across space and time. Here we study the spatiotemporal variation in predator-prey interaction networks formed by anurans and arthropods and test for the effects of prey availability in determining interaction patterns, information that is often absent and limits the understanding of the determinants of network structure. We found that network dissimilarity between ecoregions and seasons was high and primarily driven by interaction rewiring.We also found that species turnover was positively related to geographical distance. Using a null model approach to disentangle the effect of prey availability on the spatial and temporal variation, we show that differences in prey availability were important in determining the variation in network structure between seasons and among areas. Our study reveals that fluctuations in prey abundance, alongside the limited dispersal abilities of anurans and their prey, may be responsible for the spatial patterns that emerged in our predator-prey metaweb. These findings contribute to our understanding of the assembly rules that maintain biotic processes in metacommunities and highlight the importance of prey availability to the structure of these systems.


Assuntos
Cadeia Alimentar , Comportamento Predatório , Animais , Estações do Ano
14.
PeerJ ; 10: e13026, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35282285

RESUMO

Background: Currently, 58 species are assigned to the genus Allobates, with 70% of its diversity described just in the last two decades, with many additional species likely unnamed. The continuous description of these new species represents a fundamental step for resolving the taxonomy and ensuring the future conservation of the genus. Methods: Using molecular, acoustic, and morphological evidences, we describe a new species of Allobates from Teles Pires River region, southern Amazonia, and provide accounts on the population of A. tapajos found sympatrically with the new species. Results: The new species is distinguished from its congeners by the coloration of thighs, venter, dorsum, and dark lateral stripe. It has four types of calls, with advertisement calls formed by relatively long trills with a mean duration of 2.29 s ± 0.65, mean of 39.93 notes ± 11.18 emitted at a mean rate of 17.49 ± 0.68 notes per second, and mean dominant frequency of 5,717 Hz ± 220.81. The genetic distance between the new species and its congeners in a fragment of the 16S mitochondrial fragment ranged between 13.2% (A. carajas) to 21.3% (A. niputidea). The sympatric Allobates population fits its morphology and acoustic with the nominal A. tapajos, but presents a relatively high genetic distance of nearly 6.5%, raising questions on the current taxonomy of this species.


Assuntos
Anuros , Vocalização Animal , Animais , Filogenia , Anuros/genética , Brasil , Rios
15.
Sci Rep ; 12(1): 5288, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35347184

RESUMO

Hoplias malabaricus (Bloch, 1794) is a carnivorous fish species widely distributed from northern to southern South America. This taxon is believed to be a good model for the investigation of biogeographic events that shape the ichthyofauna evolution in the Neotropical freshwater systems. However, many studies have revealed that H. malabaricus hides a species complex that hampers its taxonomic identity and limit its practical value for evolutionary and biogeographic studies. In this paper, we used the mitochondrial gene cytochrome c oxidase subunit I (COI) to delimit cryptic species and explore the phylogeography of H. malabaricus sensu stricto. We found genetic evidence for putative new species in the genus Hoplias and showed that H. malabaricus (Bloch, 1794) is a major clade assigned to barcode index number (BIN) BOLD:ABZ3047. This species is structured in six subpopulations differentiated by high Fst values and restricts gene flow. The subpopulations of the São Francisco/East Atlantic/Eastern Northeast Atlantic/Parnaíba/Itapecuru River basins and Tapajós River Basin were the most differentiated and showed demographic fluctuations. The present distributional pattern is most likely explained through a scenario from the Pleistocene.


Assuntos
Caraciformes , Código de Barras de DNA Taxonômico , Animais , Caraciformes/genética , Água Doce , Filogeografia , Rios
16.
PeerJ ; 9: e12012, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595064

RESUMO

Based on concordant differences in morphology, male advertisement call, and 16S mtDNA barcode distance, we describe a new species of Proceratophrys from southern Amazonia, in the states of Mato Grosso and Pará, Brazil. The new species is most similar to P. concavitympanum and P. ararype but differs from these species by its proportionally larger eyes and features of the advertisement call. Additionally, genetic distance between the new species and its congeners is 3.0-10.4% based on a fragment of the 16S rRNA gene, which is greater than the threshold typically characterizing distinct species of anurans. Using an integrative approach (molecular, bioacoustics, and adult morphology), we were able to distinguish the new species from other congeneric species. The new species is known only from the type locality where it is threatened by illegal logging and gold mining as well as hydroelectric dams.

17.
PLoS Negl Trop Dis ; 15(9): e0009737, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34495969

RESUMO

Snake envenomation is considered a public health problem in tropical countries, where they occur in a high incidence. The present study reports the snake envenomation that occurred in Mato Grosso do Sul state (Brazil) between 2007 and 2017. Epidemiological data were obtained from the online platform of the Notification Disease Information System and were analyzed according to biome. A total of 5568 cases of snake envenomations were recorded during the study period, where the highest frequency was registered between October and April. The majority of envenomations occurred in working-age males (20 to 39 years), caused mainly by Bothrops snakes, and the duration of care after the envenomation in most cases took three hours. The municipalities that showed the highest snake envenomations case per 100,000 inhabitants presents low population density, and have their economy based on agricultural activity, which is a risk factor to snake envenomations. To the Mato Grosso do Sul state, the total number of snake envenomations had a positive relationship with the size of the municipality. Since this, larger areas usually have a mosaic of environments, which may harbor higher richness and abundance of snakes, and can cause more snake encounters with the population, resulting in more snake envenomations.


Assuntos
Mordeduras de Serpentes/epidemiologia , Adulto , Animais , Bothrops/fisiologia , Brasil/epidemiologia , Feminino , Humanos , Masculino , Estações do Ano , Mordeduras de Serpentes/parasitologia , Adulto Jovem
18.
Environ Sci Pollut Res Int ; 28(9): 11598-11617, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33128146

RESUMO

In the context of the circular bioeconomy and cleaner production, the incorporation of the by-products of plant biomass production in the bioenergy chain is fundamental. However, lignocellulosic wastes have properties that hinder their use for the production of biofuels. This study aims to evaluate how blends of lignocellulosic wastes improve the physical, chemical, and mechanical quality of pellets destined to the industrial sector, and to identify the challenges associated with the use of agroforestry biomass as raw material for pelletizing. Pellets were produced from blends of soybean wastes, sorghum wastes, pine needles, rice powder, Eucalyptus sawdust, and charcoal fines. Additionally, pure pellets composed of soybean wastes, sugarcane bagasse, and pine wood were evaluated. The effect of biomass type on the energy density, ash content, net heating value, and ultimate analysis was significant. The pellets produced with soybean wastes presented high contents of N (3.5-4.9%) and ashes (16.4-26.7%), besides low mechanical durability (≤ 96%), hindering its commercialization for industrial purposes. Pellets with sugarcane bagasse presented N (1.5%), S (0.03%), ashes (5.6%), mechanical durability (96.6%), and net heating value (15.1 MJ kg-1), suitable for industrial energy use in accordance with ISO 17225-6. The high N and ash contents and the low mechanical durability are the greatest challenges for the energy use of pellets produced from Brazilian agroforestry wastes.


Assuntos
Biocombustíveis , Lignina , Biomassa , Brasil
19.
PeerJ ; 8: e10073, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304646

RESUMO

BACKGROUND: Studies with integrative approaches (based on different lines of evidence) are fundamental for understanding the diversity of organisms. Different data sources can improve the understanding of the taxonomy and evolution of snakes. We used this integrative approach to verify the taxonomic status of Hydrodynastes gigas (Duméril, Bibron & Duméril, 1854), given its wide distribution throughout South America, including the validity of the recently described Hydrodynastes melanogigas Franco, Fernandes & Bentim, 2007. METHODS: We performed a phylogenetic analysis of Bayesian Inference with mtDNA 16S and Cytb, and nuDNA Cmos and NT3 concatenated (1,902 bp). In addition, we performed traditional morphometric analyses, meristic, hemipenis morphology and coloration pattern of H. gigas and H. melanogigas. RESULTS: According to molecular and morphological characters, H. gigas is widely distributed throughout South America. We found no evidence to support that H. gigas and H. melanogigas species are distinct lineages, therefore, H. melanogigas is a junior synonym of H. gigas. Thus, the melanic pattern of H. melanogigas is the result of a polymorphism of H. gigas. Melanic populations of H. gigas can be found in the Tocantins-Araguaia basin.

20.
PeerJ ; 8: e10189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33150083

RESUMO

The use of COI barcodes for specimen identification and species discovery has been a useful molecular approach for the study of Anura. Here, we establish a comprehensive amphibian barcode reference database in a central area of South America, in particular for specimens collected in Mato Grosso do Sul state (Brazil), and to evaluate the applicability of the COI gene for species-level identification. Both distance- and tree-based methods were applied for assessing species boundaries and the accuracy of specimen identification was evaluated. A total of 204 mitochondrial COI barcode sequences were evaluated from 22 genera and 59 species (19 newly barcoded species). Our results indicate that morphological and molecular identifications converge for most species, however, some species may present cryptic species due to high intraspecific variation, and there is a high efficiency of specimen identification. Thus, we show that COI sequencing can be used to identify anuran species present in this region.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...