Simulated climate change, but not predation risk, accelerates Aedes aegypti emergence in a microcosm experiment in western Amazonia

Climate change affects individual life-history characteristics and species interactions, including predator-prey interactions. While effects of warming on Aedes aegypti adults are well known, clarity the interactive effects of climate change (temperature and CO2 concentration) and predation risk on the larval stage remains unexplored. In this study, we performed a microcosm experiment simulating temperature and CO2 changes in Manaus, Amazonas, Brazil, for the year 2100. Simulated climate change scenarios (SCCS) were in accordance with the Fourth Assessment Report of Intergovernmental Panel on Climate Change (IPCC). Used SCCS were: Control (real-time current conditions in Manaus: average temperature is ~25.76°C ± 0.71°C and ~477.26 ± 9.38 parts per million by volume (ppmv) CO2); Light: increase of ~1, 7°C and ~218 ppmv CO2; Intermediate: increase of ~2.4°C and ~446 ppmv CO2; and Extreme: increase of ~4.5°C and ~861 ppmv CO2, all increases were relative to a Control SCCS. Light, Intermediate and Extreme SCCS reproduced, respectively, the B1, A1B, and A2 climatic scenarios predicted by IPCC (2007). We analyzed Aedes aegypti larval survivorship and adult emergence pattern with a factorial design combining predation risk (control and predator presence-Toxorhynchites haemorrhoidalis larvae) and SCCS. Neither SCCS nor predation risk affected Aedes aegypti larval survivorship, but adult emergence pattern was affected by SCCS. Accordingly, our results did not indicate interactive effects of SCCS and predation risk on larval survivorship and emergence pattern of Aedes aegypti reared in SCCS in western Amazonia. Aedes aegypti is resistant to SCCS conditions tested, mainly due to high larval survivorship, even under Extreme SCCS, and warmer scenarios increase adult Aedes aegypti emergence. Considering that Aedes aegypti is a health problem in western Amazonia, an implication of our findings is that the use of predation cues as biocontrol strategies will not provide a viable means of controlling the accelerated adult emergence expected under the IPCC climatic scenarios

Coleta da qualidade de experiência do usuário - abordagem CAARF-SDN / Experience quality collection of the user - CAARF-SDN approach

O uso intensivo das redes de computadores baseadas em IP, e a crescente demanda de utilização das aplicações de tempo real como VoIP e outras aplicações multimídia, intensifica a coexistência de tráfegos distintos na rede e a necessidade de um melhor gerenciamento dos recursos da infraestrutura. Observa-se, portanto a necessidade de uma transformação na maneira em que as redes devem se comportar, onde as decisões de encaminhamento devem ser centradas nas aplicações e em consequência ter como foco o usuário; e a Qualidade de Experiência (QoE) é fundamental para essa mudança pois muda o foco da avaliação de qualidade, da rede para o usuário. O arcabouço Context-AwareAdaptative Routing Framework (CAARF) e mais especificamente, a sua implementação baseada em redes definidas por software (CAARF-SDN), compõe uma solução de otimização de rede sensível a contexto proposta de forma a viabilizar o encaminhamento do tráfego de rede baseado em informações de contexto de forma dinâmica

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$3,616; whereas for fish, the total was US$ 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

Global trends in research on the effects of climate change on Aedes aegypti: international collaboration has increased, but some critical countries lag behind

Background: Mosquito‑borne diseases (e.g., transmitted by Aedes aegypti) affect almost 700 million people each year and result in the deaths of more than 1 million people annually. Methods: We examined research undertaken during the period 1951–2020 on the effects of temperature and climate change on Ae. aegypti, and also considered research location and between‑country collaborations. Results: The frequency of publications on the effects of climate change on Ae. aegypti increased over the period examined, and this topic received more attention than the effects of temperature alone on this species. The USA, UK, Australia, Brazil, and Argentina were the dominant research hubs, while other countries fell behind with respect to number of scientific publications and/or collaborations. The occurrence of Ae. aegypti and number of related dengue cases in the latter are very high, and climate change scenarios predict changes in the range expansion and/or occurrence of this species in these countries. Conclusions: We conclude that some of the countries at risk of expanding Ae. aegypti populations have poor research networks that need to be strengthened. A number of mechanisms can be considered for the improvement of international collaboration, representativity and diversity, such as research networks, internationalization programs, and programs that enhance representativity. These types of collaboration are considered important to expand the relevant knowledge of these countries and for the development of management strategies in response to climate change scenarios

Structuring functional groups of aquatic insects along the resistance/resilience axis when facing water flow changes

Understanding how differences in intensity and frequency of hydrological disturbances affect the resistance and resilience of aquatic organisms is key to manage aquatic systems in a fast-changing world. Some aquatic insects have strategies that improve the permanence (resistance), while others use strategies that favor recolonization (resilience). Therefore, we carried out a manipulative experiment to understand the influence of functional characteristics of aquatic insects in their permanence and recolonization against hydrological disturbances in streams in the biodiversity hotspot of the Cerrado of Brazil. We placed 200 artificial substrates in five streams and submitted them to changing water flow regimes that differed both in frequency and intensity, and we observed the response of the aquatic community for 39 days. We used a hierarchical Bayesian approach to estimate the probabilities of permanence and recolonization of each life strategy group (nine groups). We observed that the most intense changes in the water flow tended to affect the permanence of almost all groups, but the intensity of this effect reduced over time. On the other hand, less frequent disturbances, regardless of intensity, tended to reduce the permanence of most groups of aquatic insects over time. The different effects of disturbance intensity may have been related to a greater recolonization capacity of some groups. The results we present are worrisome in a scenario of reduced riparian vegetation around streams and with the expectation of precipitation becoming more concentrated in shorter periods of time due to climate change in the Cerrado hotspot, reducing the occurrence of many groups of aquatic insects in their habitat, particularly those with traits associated with resistance against hydrological disturbance

Seasonality modulates the direct and indirect influences of forest cover on larval anopheline assemblages in western Amazônia

Serious concerns have arisen regarding urbanization processes in western Amazônia, which result in the creation of artificial habitats, promoting the colonization of malaria vectors. We used structural equation modelling to investigate direct and indirect effects of forest cover on larval habitats and anopheline assemblages in different seasons. We found 3474 larvae in the dry season and 6603 in the rainy season, totalling ten species and confirming the presence of malaria vectors across all sites. Forest cover had direct and indirect (through limnological variables) effects on the composition of larval anopheline assemblages in the rainy season. However, during the dry season, forest cover directly affected larval distribution and habitat variables (with no indirect affects). Additionally, artificial larval habitats promote ideal conditions for malaria vectors in Amazonia, mainly during the rainy season, with positive consequences for anopheline assemblages. Therefore, the application of integrated management can be carried out during both seasons. However, we suggest that the dry season is the optimal time because larval habitats are more limited, smaller in volume and more accessible for applying vector control techniques

Loss of Cultural and Functional Diversity Associated With Birds Across the Urbanization Gradient in a Tropical City

Birds provide many ecosystem services to people, including provisioning, regulating and cultural services. People attribute multiple cultural values to ecosystems and biodiversity and the diversity of these cultural values can be considered as cultural diversity. While human-nature interactions occur more frequently in cities and urbanization negatively affects different facets of avian biodiversity, little is known about its consequence for cultural diversity. Here, we assess how the urbanization gradient in Campo Grande, a Brazilian city in the Cerrado biodiversity hotspot, affects functional and cultural diversity associated with birds and if functional and cultural diversity are congruent. We also investigate the relation between urbanization gradient with functional traits and cultural values, weighted by species abundance. We used a dataset based on bird surveyed in 61 landscapes along a gradient of impervious surface cover. To estimate functional and cultural diversity, we used indices that estimate richness and divergence of functional traits and cultural values. We found that urbanization affected functional and cultural richness negatively, while there was no effect on functional and cultural divergence. Functional and cultural richness and functional and cultural divergence were weakly, but significantly correlated. Bird species that nest on trees decreased and those that nest in artificial structures and on the ground increased along the impervious surface gradient. Body size, diet, habitat, mating system, flock behavior, and all cultural values (number of times the species was mentioned by football teams, music or poetry, city flags and anthems, and folklore tales) were not significantly affected by impervious surface. The negative relationship between impervious surface and bird cultural richness may indicate that people living in more urbanized areas experience nature less compared to people in less urbanized areas, which can affect their psychological well-being. In these highly urbanized areas, contact with culturally valued birds and cultural services provided by birds may also diminish. The negative relationship between functional richness and urbanization also indicate that highly urbanized areas may be losing important ecosystems services provided by birds

Periapical surgery to remove granulomatous lesion: case report

Granuloma periapical é um termo histológico que refere-se à formação de uma massa de tecido granulomatoso ao redor do ápice de um dente, decorrente da inflamação e necrose do tecido pulpar. É constituído por um infiltrado de células inflamatórias como macrófagos, plasmócitos e linfócitos, além de fibroblastos, fibras colágenas e capilares. A cirurgia do periápice é uma alternativa para preservação do dente na cavidade bucal nos casos em que a inflamação periapical é persistente mesmo após tratamento dos canais radiculares. O objetivo desse trabalho é relatar um caso clínico no qual a técnica cirúrgica do periápice foi utilizada para remoção de lesões granulomatosas de uma paciente, do sexo feminino, com histórico de abscesso periapical recidivante sem sintomatologia dolorosa na região dos dentes anteriores superiores 11, 12 e 13. O exame histopatológico demonstrou a presença de um tecido granulomatoso com intenso infiltrado inflamatório misto, permeado com linfócitos e elevado número de plasmócitos, confirmando o diagnóstico de granuloma periapical. O tratamento foi considerado exitoso, visto que a paciente se manteve asintomática e houve incorporação do enxerto ósseo bovino inorgânico e início da neoformação óssea na região periapical.Periapical granuloma is a histological term that refers to the formation of a mass of granulomatous tissue around the apex of a tooth resulting from inflammation and necrosis of the pulp tissue. It consists of an infiltrate of inflammatory cells such as macrophages, plasmocytes and lymphocytes, as well as fibroblasts, collagen fibers and capillaries. Periapical surgery is an alternative for preserving the tooth in the oral cavity in cases where periapical inflammation is persistent even after treatment of root canals. The objective of this study was to report a clinical case in which the surgical technique was used to remove granulomatous lesions from a patient, female, with a history of recurrent periapical abscess without painful symptomatology in the region of the anterior 11,12 and 13 teeth. The histopathological exam demonstrated the presence of a granulomatous tissue with intense inflammatory infiltrate mixed, permeated with lymphocytes and high number of plasmocytes, confirming the diagnosis of periapical granuloma. The treatment was considered successful since the patient remained asymptomatic and there was incorporation of the inorganic bovine bone graft and initiation of bone neoformation in the periapical region

Molecular architecture of the antiophidic protein DM64 and its binding specificity to myotoxin II from Bothrops aasper venom

Open access article. Creative Commons Attribution 4.0 International License (CC BY 4.0) appliesDM64 is a toxin-neutralizing serum glycoprotein isolated from Didelphis aurita, an ophiophagous marsupial naturally resistant to snake envenomation. This 64 kDa antitoxin targets myotoxic phospholipases A2, which account for most local tissue damage of viperid snakebites. We investigated the noncovalent complex formed between native DM64 and myotoxin II, a myotoxic phospholipase-like protein from Bothrops asper venom. Analytical ultracentrifugation (AUC) and size exclusion chromatography indicated that DM64 is monomeric in solution and binds equimolar amounts of the toxin. Attempts to crystallize native DM64 for X-ray diffraction were unsuccessful. Obtaining recombinant protein to pursue structural studies was also challenging. Classical molecular modeling techniques were impaired by the lack of templates with more than 25% sequence identity with DM64. An integrative structural biology approach was then applied to generate a three-dimensional model of the inhibitor bound to myotoxin II. I-TASSER individually modeled the five immunoglobulin-like domains of DM64. Distance constraints generated by cross-linking mass spectrometry of the complex guided the docking of DM64 domains to the crystal structure of myotoxin II, using Rosetta. AUC, small-angle X-ray scattering (SAXS), molecular modeling, and molecular dynamics simulations indicated that the DM64-myotoxin II complex is structured, shows flexibility, and has an anisotropic shape. Inter-protein cross-links and limited hydrolysis analyses shed light on the inhibitor’s regions involved with toxin interaction, revealing the critical participation of the first, third, and fifth domains of DM64. Our data showed that the fifth domain of DM64 binds to myotoxin II amino-terminal and beta-wing regions. The third domain of the inhibitor acts in a complementary way to the fifth domain. Their binding to these toxin regions presumably precludes dimerization, thus interfering with toxicity, which is related to the quaternary structure of the toxin. The first domain of DM64 interacts with the functional site of the toxin putatively associated with membrane anchorage. We propose that both mechanisms concur to inhibit myotoxin II toxicity by DM64 binding. The present topological characterization of this toxin-antitoxin complex constitutes an essential step toward the rational design of novel peptide-based antivenom therapies targeting snake venom myotoxins.Ye