896 research outputs found
Heterogeneidade ambiental e comunidade de anuros em agroecossistema na região do Pantanal, Brasil
The Pantanal of central Brazil has experienced considerable modifications as a result of growing land use. The association between anuran assemblage and the local habitat structure of an agroecosystem in central Brazil at the Pantanal is described. It is shown that the structure of the anuran community is reestablished within the new environmental dynamics in such human-modified habitat. Twenty-four anuran species were recorded in the area. The community was dominated by four species (Dendropsophus nanus, Leptodactylus chaquensis, Hypsiboas raniceps, and Rhinella cf. bergi), which accounted for more than 50% of the sampled individuals. The species distribution pattern was adjusted to the logarithmic, log-normal, and broken stick models, partially reflecting its association with agroecosystem characteristics. Habitat heterogeneity contributes to the anuran community at a local scale, thereby emphasizing the importance of maintaining distinct habitats for anuran species in the Pantanal as a management practice, even in in situations in which anthropic actions are predictable, as in agroecosystems.A planície pantaneira no Brasil Central tem sofrido intensa modificação devido às práticas de ocupação antrópica ocorrida nos últimos anos na região. Este trabalho ilustra a associação entre a comunidade de anfíbios anuros e a estrutura ambiental em escala local de um agroecossistema no Pantanal (Mato Grosso do Sul) e mostra que em ambientes modificados pela ação humana a comunidade de anuros pode ser restabelecida de acordo com as novas condições encontradas. Foram encontradas 24 espécies de anuros das quais quatro foram predominantes (Dendropsophus nanus, Leptodactylus chaquensis, Hypsiboas raniceps e Rhinella cf. bergi), representando mais de 50% dos indivíduos amostrados. O padrão de distribuição das espécies foi melhor ajustado aos modelos logarítmicos, log-normal e broken stick, refletindo parcialmente uma associação com as características do agroecossistema. A heterogeneidade ambiental contribuiu com a estrutura da comunidade, o que reforça a importância da manutenção de ambientes distintos para as espécies de anuros do Pantanal como uma prática de manejo mesmo em situações em que as ações antrópicas forem previsíveis e irreversíveis como os agroecossistemas
Amphibians and reptiles of the serra da bodoquena national park, Mato Grosso do Sul, central Brazil.
O Estado de Mato Grosso do Sul situa-se na porção mediana da grande diagonal de formações abertas da América do Sul, uma região que abriga uma grande diversidade de anfíbios e répteis, sendo algumas endêmicas. Apesar de sua importância biogeográfica, essa diagonal tem sido pouco considerada em estudos com abrangência regional. Dentre os componentes fitofisionômicos que compõem essa região e cuja representatividade se faz presente no Estado, as matas estacionais deciduais são elementos marcantes na região da Serra da Bodoquena. Devido a peculiaridade desse ambiente, muitas áreas ainda necessitam de uma maior avaliação quanto à sua biodiversidade. Informações sobre a herpetofauna do Parque Nacional da Serra da Bodoquena são escassas e pontuais e sugerem uma semelhança com a fauna de cerrado. Este trabalho apresenta registros da herpetofauna do Parque Nacional da Serra da Bodoquena e regiões de entorno, abrangendo áreas em bom estado de conservação e locais com atividade agropecuária. As amostragens foram realizadas em dois períodos, contemplando as estações seca e chuvosa na região. O inventário consistiu em busca ativa limitada por tempo, além de registros oportunísticos. Informações sobre a riqueza de espécies da herpetofauna da Caatinga, Cerrado e Chaco foram compiladas da literatura e comparadas com aquela registrada no presente trabalho. Foram registradas 64 espécies, sendo 38 anfíbios e 25 répteis. Muitas das espécies estavam associadas a ambientes particulares, como matas de galeria e afloramentos rochosos. A maior similaridade da herpetofauna do Parque Nacional da Serra da Bodoquena deu-se com aquela encontrada no Cerrado, provavelmente porque a área está inserida nesse bioma. Considerando-se a diversidade de hábitats da área, provavelmente o número de espécies deverá aumentar com a realização de novos inventários na região. Agregar novas informações sobre a herpetofauna da Serra da Bodoquena é fundamental para o plano de manejo do Parque Nacional.The State of Mato Grosso do Sul, central Brazil, is located in the center of the broad South American open-dry diagonal areas. This region harbors a great diversity of amphibians and reptiles, with some endemic species. Despite such biogeographical scenario, biodiversity of this region is poorly known at local scales. Dry forests are important physiognomies in Mato Grosso do Sul and represent an important landscape element at Serra da Bodoquena, resulting in local characteristics that require biodiversity surveys. There are few and punctual information on the herpetofauna from the Serra da Bodoquena National Park and they suggest a similarity with the Cerrado herpetofauna. The present study represents the first record of the herpetofauna from the Serra da Bodoquena National Park and adjacent areas. Samples were conducted in pristine and disturbed areas in two distinct climatic periods, covering both rainy and dry seasons, by means of active search limited by time as well as opportunistic records. Data on the herpetofauna of the Caatinga, Cerrado, and Chaco biomes were compiled and compared with the species sampled in the present study. We registered 63 species, including 38 amphibians and 25 reptiles. Several species were associated to particular habitats, such as gallery forests or rocky outcrops. The herpetofauna from the Serra da Bodoquena National Park showed a greater similarity with that of the Cerrado, probably because the area is inserted in this biome. Considering the habitat diversity found at Serra da Bodoquena, the number of species must increase with other surveys in the area. Natural history and ecological studies on amphibian and reptiles of the Serra da Bodoquena must be encouraged in order to contribute for the National Park management
Feeding habits of Mesoclemmys vanderhaegei (Testudines: Chelidae)
We studied the feeding habits of Mesoclemmys vanderhaegei in small water bodies in the central region of the Brazilian Cerrado. We captured 80 individuals, 79 of which [41 (52%) females, 27 males (34%), 11 (14%) juveniles] had stomach contents for analysis. We identified 64 food item categories. The turtles were eating more animal than plant material, aquatic invertebrates being the most conspicuous diet item found. Plant material was more abundant in females and rare in the diet of juveniles. Mesoclemmys vanderhaegei proved to be an omnivorous and opportunistic chelonian, feeding on a wide range of food items. Although there are differences in the consumption of food items among sexes and age categories, the most consumed food categories were common in all water bodies sampled
Efeitos do tramadol sobre variáveis clínicas e limiar nociceptivo mecânico em equinos
Avaliaram-se os efeitos clínicos e o potencial antinociceptivo mecânico de diferentes doses de tramadol administradas por via intravenosa (IV) em equinos. Sete animais foram tratados com 1 (Tr1), 2 (Tr2) ou 3 (Tr3) mg kg-1de tramadol IV em um estudo cruzado do tipo cego e randomizado. Foram avaliados frequência cardíaca, frequência respiratória, temperatura retal, pressão arterial, nível de sedação, motilidade gastrointestinal, alterações comportamentais e limiar antinociceptivo mecânico (Von Frey). As principais alterações evidenciadas pela administração do tramadol concentram-se no aumento na frequência respiratória em Tr3, aumento signifi cativo da pressão arterial em Tr1 e redução da motilidade gastrointestinal, mais pronunciada em Tr2. O tramadol não promoveu alteração signifi cativa no limiar nociceptivo mecânico. As alterações clínicas observadas nos diferentes tratamentos foram consideradas leves e transitórias. Diante dos resultados, pode-se concluir que o tramadol não apresentou efeito antinociceptivo passível de ser avaliado pelo método empregado no presente estudo, em nenhum dos tratamentos. _________________________________________________________________________________ ABSTRACTThis study assessed the clinical effects and the mechanical antinociceptive potential of intravenous (IV) tramadol in horses.A blinded and randomized study was designed with 7 horses treated with 1 (Tr1), 2 (Tr2) or 3 (Tr3) mg kg-1 of tramadol IV. The heart rate, respiratory rate (fR), arterial pressure, degree of sedation, gastrointestinal motility (GI), behavior changes and the mechanical nociceptive threshold (MNT) were evaluated. The MNT was determined with von Frey device method.Tr3 had a signifi cant increase in their fR and more pronounced behavioral changes than other treatments.The Tr1 showed a signifi cant increase in arterial pressure. The GI reduced signifi cantly, mainly in Tr2. The tramadol did not change the MNT of the horses.The clinical alterations observed with the different treatments were considered mild and transitory, being most evident in Tr2. However the tramadol did not have any analgesic effect with any of the doses evaluated
Numerical investigation of the three-dimensional secondary instabilities in the time-developing compressible mixing layer
Mixing layers are present in very different types of physical situations such as atmospheric flows, aerodynamics and combustion. It is, therefore, a well researched subject, but there are aspects that require further studies. Here the instability of two-and three-dimensional perturbations in the compressible mixing layer was investigated by numerical simulations. In the numerical code, the derivatives were discretized using high-order compact finite-difference schemes. A stretching in the normal direction was implemented with both the objective of reducing the sound waves generated by the shear region and improving the resolution near the center. The compact schemes were modified to work with non-uniform grids. Numerical tests started with an analysis of the growth rate in the linear regime to verify the code implementation. Tests were also performed in the non-linear regime and it was possible to reproduce the vortex roll-up and pairing, both in two-and three-dimensional situations. Amplification rate analysis was also performed for the secondary instability of this flow. It was found that, for essentially incompressible flow, maximum growth rates occurred for a spanwise wavelength of approximately 2/3 of the streamwise spacing of the vortices. The result demonstrated the applicability of the theory developed by Pierrehumbet and Widnall. Compressibility effects were then considered and the maximum growth rates obtained for relatively high Mach numbers (typically under 0.8) were also presented.AFOSR Air Force Office of Scientific Research[FA9550-07-1-0055]FAPES
Xenodon pulcher (Jan, 1863) (Serpentes: Dipsadidae) first record for Brazil and a distribution extension
Xenodon is a South American snake genus with 11 species distributed from Guyanas, Brazil, Uruguay, Bolivia, Paraguay and Argentina. Xenodon pulcher is known from Argentina, Bolivia and Paraguay, associated to Chaco ecoregion. After a revision of material located in the Coleção Zoológica de Referência da Universidade Federal de Mato Grosso do Sul (ZUFMS) we found specimens of Xenodon sp. from Porto Murtinho municipality bordering Paraguay, a small area in Brazil harboring chaco vegetation. Ventral, subcaudales, pre-oculars scales and complete triads in the body and tail of 23 specimens of X. pulcher from Paraguay, 32 of X. mattogrossensis from Brazilian pantanal and four specimens of Xenodon sp. collected in Porto Murtinho, Mato Grosso do Sul, Brazil. There is a high variation and overlap between the characters of X. pulcher and X. mattogrossensis; however X. mattogrossensis differs from X. pulcher and X. semicinctus in the presence of lateral white spots on the black rings, and the specimens from Porto Murtinho do not have these spots. This is the first record of the species in Brazil.Fil: Cabral, Hugo. Asociación Guyra; Paraguay. Instituto de Investigación Biológica del Paraguay; ParaguayFil: Piatti, Liliana. Universidade de Sao Paulo; BrasilFil: de Souza, Franco Leandro. Universidade Federal do Mato Grosso Do Sul; BrasilFil: Scrocchi Manfrini, Gustavo Jose. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Herpetología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ferreira, Vánda Lucía. Universidade Federal do Mato Grosso Do Sul; Brasi
Advertisement and release calls of Rhinella scitula (Caramaschi and Niemeyer, 2003) (Anura: Bufonidae)
The anuran calls descriptions have given important taxonomic information in studies within problematic species group. Herein, we describe the advertisement and release calls of R. scitula.
We analyzed calls recorded in three localities in Mato Grosso do Sul state, Brazil, including the type locality. Males were calling at the margins of permanent streams in forest fragments ca. 21:00 h. The advertisement call of R. scitula is multi-pulsed with interior amplitude modulation, resulting in pulse groups. Males emitted non-regular call series with duration of 0.27s ± 0.03 (0.23–0.36), note duration of 0.015s ± 0.004 (0.007–0.040), pulse duration of 0.008s ± 0.001 (0.005–0.015, n=180), pulse group per call of 6.6 ± 0.92 (5–8) and dominant frequency of 1439.7 Hz ± 46.1 (1378.1–1550.4). The release calls were characterized by a dominant frequency of 1115.8Hz ± 102.2 (947.5–1550.4), a frequency bandwidth of 2001.6Hz ± 527.4 (861.3–3876).
They are formed by pulsed and/or pulsatile notes spaced by non-regular intervals or series of 2–19 calls. From all R. margaritifera species group with described advertisement calls, the most different to R. scitula and other species in the group was R. magnussoni, which has a structurally distinct call. The release calls in R. granulosa species group and R. scitula has the same pattern of pulsed and/or non-pulsed notes.Asociación Herpetológica Argentin
Species composition and richness of anurans in Cerrado urban forests from central Brazil
Brazil harbors the greatest diversity of amphibians on the planet although there are few studies dealing with urban fauna. The objective of this study is to describe the species composition and richness of anurans in urban Cerrado fragments from Campo Grande municipality, Mato Grosso do Sul state, central Brazil. The specimens were sampled in three stages through pitfall traps and visual/acoustic surveys. Seventeen species were recorded (17.7% of anuran species registered in Mato Grosso do Sul), with Leptodactylidae and Hylidae being the most represented families. The existence of a high number of green areas and water bodies in the urban area likely favors anuran species in the region. The anuran communities in urban areas of Campo Grande were dominated by species which use a broad range of habitats. In this study there was the record of a new species of anuran, Proceratophrys dibernardoi, for the state of Mato Grosso do Sul. The forest fragments that had the highest similarity for species composition were those with similar environmental conditions. The knowledge of the fauna that occurs in urban areas is important because natural habitats suffer severe fragmentation and degradation and species present in these areas may disappear in a shorter period of time
Princípios didáticos e movimentos para uma “Obutchénie por Unidades”
The formation of a theoretical thinking with scientific concepts in school education finds its constitutive unit in the dialectical relation of the obutchénie-development process. However, such objectification implies teacher didactic-pedagogical appropriation and student self-transformation. In the text, we approach didactic movements and principles, as possible syntheses, resulting from this process in a set of theoretical-practical research in public schools of MG, developed in the light of historical-cultural theory, developmental didactics, historical-dialectical method and didactic-formative intervention. Results point out that the essence of this process operates through "units" (Longarezi, 2017).La formación de un pensamiento teórico con conceptos científicos en la educación escolar encuentra su unidad constitutiva en la relación dialéctica del proceso obutchénie-desarrollo. Sin embargo, tal objetivación implica apropiación didáctica-pedagógica del profesor y autotransformación del estudiante. En el texto, abordamos movimientos y principios didácticos, como síntesis posibles, resultantes de este proceso en un conjunto de investigaciones teórico-prácticas en escuelas públicas de MG, desarrollado a la luz de la teoría histórico-cultural, didáctica desarrolladora, método histórico-dialéctico e intervención didáctico-formativo. Los resultados apuntan que la esencia de este proceso se opera por las "unidad" (Longarezi, 2017).La formation d'une pensée théorique avec des concepts scientifiques dans l'enseignement scolaire trouve son unité constitutive dans la relation dialectique du processus d'obutchénie-développement. Cependant, cette objectivation implique une appropriation didactique-pédagogique des enseignants et une auto-transformation des élèves. Dans ce texte, nous abordons les mouvements et les principes didactiques comme des synthèses possibles résultant de ce processus dans un ensemble de recherches théorico-pratiques auprès des écoles publiques de MG, développées à la lumière de la théorie historico-culturelle, de la didactique développementale, et de la méthode didactique formatif. Les résultats soulignent que l'essence de ce processus passe par des "unités" (Longarezi, 2017).A formação de um pensar teórico com conceitos científicos na educação escolar encontra sua unidade constitutiva na relação dialética do processo “obutchénie- desenvolvimento”. Entretanto, tal objetivação implica apropriação didático-pedagógica do professor e autotransformação do estudante. No texto, abordamos movimentos e princípios didáticos, como sínteses possíveis, decorrentes desse processo em um conjunto de pesquisas teórico-práticas em escolas públicas de MG, desenvolvido à luz da teoria histórico-cultural, didática desenvolvimental, método histórico-dialético e intervenção didático-formativa. Resultados apontam que a essência desse processo opera-se pelas “unidades” (Longarezi, 2017)
Incorporating costs, thresholds and spatial extents for selecting stream bioindicators in an ecotone between two Brazilian biodiversity hotspots
Biomonitoring is critical for characterizing and monitoring status, spatial patterns, and long-term trends in the ecological condition of freshwater ecosystems. The selection of cost-effective bioindicators is a critical step in establishing such monitoring programs. Key indicator considerations are a reliable response to anthropogenic disturbances, a high benefit-cost-ratio and sensitivity at multiple spatial extents. We evaluated non-linear responses of Ephemeroptera, Plecoptera and Trichoptera (EPT) and fish to the effects of native vegetation loss within buffers of 100 m and 1000 m and assessed the sampling and processing costs involved for each assemblage. We sampled 37 neotropical stream sites in the Formoso River network, a karstic region of the Bodoquena Plateau, midwest Brazil, lying in the ecotone between the Cerrado and Atlantic Forest biological hotspots. We used TITAN (threshold indicator taxa analysis) to identify six indicator taxa, four EPT genera and two fish species. The four EPT genera had low negative thresholds to native vegetation loss, whereas the two fish species had positive thresholds. Thresholds were lower for the 100 m buffers than the 1000 m buffers for EPT. The most sensitive taxon (Macronema, Trichoptera) had a threshold of 0% native vegetation loss in the 100 m buffers and nearly 40% in the 1000 m buffers. For taxa richness, we found no non-linear response to the effects of native vegetation loss for buffer extent nor assemblage. The total cost for EPT biomonitoring was US 1,901. Although fish were less expensive than EPT, they did not respond negatively to native vegetation loss and their positive threshold started at 48%, a level of vegetation loss that was highly disruptive of EPT. Therefore, we do not recommend using fish to monitor the effects of native vegetation loss on headwater streams in the Bodoquena Plateau. Although EPT monitoring costs 52% more than fish assemblage monitoring, it detected earlier impacts of the effects of native vegetation loss on stream biota, especially in the 100 m buffer. Therefore, EPT are more cost-effective early warning indicators for monitoring the effects of native vegetation loss in Bodoquena Plateau headwaters
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