827 research outputs found

    Microbial community dynamics in diesel waste biodegradation using sequencing batch bioreactor operation mode (SBR)

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    The dynamic of molecular microbial community during diesel waste biodegradation was investigated. The waste was treated in bioreactors operated in sequencing batch operation mode (SBR) in four cycles of 72 h, using optimized setpoints (pH, initial waste load, C:N ratio, aeration). Optimal conditions allowed the system to reach biodegradation of 53.3, 96.0, 76.2 and 75.0% at the end of cycles one, two three and four, respectively. Oxygen uptake rate (OUR) indicated increases in microbial activity from cycle one to cycle two (124.9 to 252.9 mgO2/L/h) and decreases in cycles three and four (120.4 to 108.8 mgO2/L/h, respectively). Investigations of microbial diversity showed changes in the microbial community members at the end of the cycle one. Significant reductions in the relative ecotoxicity were observed beginning with cycle two, and the reductions extended until the end of process. The SBR operation mode proved to be an efficient method for treating the diesel waste, and the process allowed for relevant reductions in the hydrocarbon content of the waste along with an increase in its environmental quality. Changes in the microbial members are evidence of the synergistic action of the microbiota in the process.Key words: Microbial diversity, denaturing gradient gel electrophoresis, sequencing batch, biodegradation

    ATENA–A Novel Rapidly Manufactured Medical Invasive Ventilator Designed as a Response to the COVID-19 Pandemic: Testing Protocol, Safety, and Performance Validation

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    Background: The urgent need for mechanical ventilators to support respiratory insufficiency due to SARS-CoV-2 led to a worldwide effort to develop low-cost, easily assembled, and locally manufactured ventilators. The ATENA ventilator project was developed in a community-based approach targeting the development, prototyping, testing, and decentralized manufacturing of a new mechanical ventilator. Objective: This article aims to demonstrate ATENA's adequate performance and safety for clinical use. Material: ATENA is a low-cost ventilator that can be rapidly manufactured, easily assembled, and locally produced anywhere in the world. It was developed following the guidelines and requirements provided by European and International Regulatory Authorities (MHRA, ISO 86201) and National Authorities (INFARMED). The device was thoroughly tested using laboratory lung simulators and animal models. Results: The device meets all the regulatory requirements for pandemic ventilators. Additionally, the pre-clinical experiences demonstrated security and adequate ventilation and oxygenation, in vivo. Conclusion: The ATENA ventilator had a good performance in required tests in laboratory scenarios and pre-clinical studies. In a pandemic context, ATENA is perfectly suited for safely treating patients in need of mechanical ventilation.Financial support and sponsorship by CEiiA, INOV4COVID program, donations from scientific patronage, and commercial sales

    Identifying hotspots for ecosystem restoration across heterogeneous tropical savannah-dominated regions.

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    This is the final version. Available from the Royal Society via the DOI in this record. There is high potential for ecosystem restoration across tropical savannah-dominated regions, but the benefits that could be gained from this restoration are rarely assessed. This study focuses on the Brazilian Cerrado, a highly species-rich savannah-dominated region, as an exemplar to review potential restoration benefits using three metrics: net biomass gains, plant species richness and ability to connect restored and native vegetation. Localized estimates of the most appropriate restoration vegetation type (grassland, savannah, woodland/forest) for pasturelands are produced. Carbon sequestration potential is significant for savannah and woodland/forest restoration in the seasonally dry tropics (net biomass gains of 58.2 ± 37.7 and 130.0 ± 69.4 Mg ha-1). Modelled restoration species richness gains were highest in the central and south-east of the Cerrado for savannahs and grasslands, and in the west and north-west for woodlands/forests. The potential to initiate restoration projects across the whole of the Cerrado is high and four hotspot areas are identified. We demonstrate that landscape restoration across all vegetation types within heterogeneous tropical savannah-dominated regions can maximize biodiversity and carbon gains. However, conservation of existing vegetation is essential to minimizing the cost and improving the chances of restoration success. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.Natural Environment Research Council (NERC)Natural Environment Research CouncilFAPESP (São Paulo Research Foundation)NordesteUKR
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