72 research outputs found

    Pyrites in a salt marsh-ria system: quantification, morphology, and mobilization

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    Galician Rias are among the most productive ecosystems in the world. Consequently, the soils of their salt marshes and sediments of the intertidal flats show high organic matter contents, reactive Fe, and sulfate, which promote pyrite synthesis and accumulation, using sulfate for organic matter decomposition. This work studies the morphological variability and concentration of pyrites (individual crystals and framboids) in different geochemical environments found in the Ria de Ortigueira (salt marsh soils and bottom sediments in the inner, middle, and outer section), addressing their dynamics in the marsh-ria system in relation to the hydrodynamic characteristics defined by tides and river discharges. Framboidal pyrites were the dominant morphology in marsh soils and sediments in the middle and inner sections of the Ria, while isolated crystals dominated its outer section. The results showed that lower marsh soils (colonized by Spartina) are the most favorable environment for pyrite synthesis, showing high pyritic Fe concentrations and high degrees of pyritization, largely exceeding the values observed in sediments from Galician Rias and from most sedimentary environments worldwide. However, the amount of framboidal pyrites present in the lower marsh (SPE: 4–5 × 104 framboids) was clearly lower than in bottom sediments of the inner and middle part of the Ria de Ortigueira (∌2–7 × 106 framboids), mainly due to the fact that pyrites were found to form large framboids in lower salt marsh soils. Thus, the amount of framboidal pyrites does not seem to be a good indicator of redox conditions in modern marine sediments. Pyrite crystals found in the sediments of the Ria showed poorly defined vertices and facets, indicating their degradation and suggesting that a significant amount of the pyrites found in the middle and inner sections derive from marsh collapse. Finally, the output of framboidal pyrites towards the outer Ria de Ortigueira reflects the low intensity of residual flows in this Ria. Therefore, the pyrites observed in the outer section consisted only of isolated crystals, presumably formed in situ under low sulfate-reducing activity conditionsS

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Gypsum Amendment Induced Rapid Pyritization in Fe-Rich Mine Tailings from Doce River Estuary after the FundĂŁo Dam Collapse

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    Mine tailings containing trace metals arrived at the Doce River estuary, after the world’s largest mine tailings disaster (the Mariana disaster) dumped approximately 50 million m3 of Fe-rich tailings into the Doce River Basin. The metals in the tailings are of concern because they present a bioavailability risk in the estuary as well as chronic exposure hazards. Trace metal immobilization into sulfidic minerals, such as, pyrite, plays a key role in estuarine soils; however, this process is limited in the Doce River estuarine soil due to low sulfate inputs. Thus, to assess the use of gypsum amendment to induce pyritization in deposited tailings, a mesocosm experiment was performed for 35 days, with vinasse added as carbon source and doses of gypsum (as a sulfate source). Chemical and morphological evidence of Fe sulfide mineral precipitation was observed. For instance, the addition of 439 mg of S led to the formation of gray and black spots, an Fe2+ increase and decrease in sulfides in the solution, an increase in pyritic Fe, and a greater Pb immobilization by pyrite at the end of the experiment. The results show that induced pyritization may be a strategy for remediating metal contamination at the Doce River estuaryThis work was funded by grants to AFB and TOF from Fundação de Amparo do Espirito Santo (FAPES/CNPq/CAPES Rio Doce 77683544/2017), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior CAPES—Finance Code 001 and CNPq (grant numbers, AFB: 301161/2017-8, TOF: 305996/2018-5; GNN: 409593/2018-4). The authors are grateful for the financial support provided by São Paulo Research Foundation (FAPESP, ADF grant number 2019/14800-5, HMQ grant number 2018/04259-2; MPK grant number 2020/06224-1; TOF grant numbers 2019/19987-6 and 2018/08408-2). Xunta de Galicia-Consellería de Educación e Ordeanción Universitaria de Galicia (Consolidation of competitive groups of investigation; GRC GI 1574) and CRETUS strategic group (AGRUP2015/02). Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (GNN, JCNE Grant E-26/202.757/2019)S

    Avaliação da analgesia de opioide tĂłpico em Ășlcera de perna de paciente falcĂȘmico

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    A doença falciforme Ă© caracterizada por apresentar vĂĄrias alteraçÔes clinicas e fisiopatolĂłgicas nos pacientes que por ela sĂŁo acometidos. Uma dessas alteraçÔes Ă© presença de Ășlceras de perna dolorosas e de difĂ­cil cicatrização, sendo necessĂĄrio o apoio de equipe multiprofissional no seu manejo e tratamento. Com o objetivo de reduzir a dor associada a Ășlcera de perna, o paciente falcĂȘmico faz uso de opioides parenterais e enterais que normalmente estĂŁo associados a efeitos colaterais indesejados. Com o objetivo de reduzir o uso desses opioides sistĂȘmicos, avaliamos um gel de morfina, de fĂĄcil manipulação e baixo custo, que foi utilizado antes e apĂłs o processo de troca de curativo das Ășlceras de perna dos pacientes falcĂȘmicos atendidos em nossa instituição. Baseados na escala analĂłgica da dor foi avaliado o efeito analgĂ©sico do gel em 28 pacientes. Todos apresentavam dor grau 7 ou 8 antes da aplicação do gel. Vinte e quatro pacientes (85,7%) apresentaram total ausĂȘncia de dor por um perĂ­odo de 24 horas, nĂŁo sendo necessĂĄrio o uso de analgĂ©sicos sistĂȘmicos. Em trĂȘs pacientes (10,7%) a ausĂȘncia de dor durou um periodo de 12horas. Somente um paciente (3,6%) nĂŁo relatou analgesia apos o uso do gel. Os resultados demonstraram que o gel Ă© altamente eficaz no controle da dor das Ășlceras de perna de pacientes falcĂȘmicos

    Avaliação da analgesia de opioide tĂłpico em Ășlcera de perna de paciente falcĂȘmico Evaluation of the topical application of opioid analgesia for a leg ulcer of a sickle cell disease patient

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    A doença falciforme Ă© caracterizada por apresentar vĂĄrias alteraçÔes clinicas e fisiopatolĂłgicas nos pacientes que por ela sĂŁo acometidos. Uma dessas alteraçÔes Ă© presença de Ășlceras de perna dolorosas e de difĂ­cil cicatrização, sendo necessĂĄrio o apoio de equipe multiprofissional no seu manejo e tratamento. Com o objetivo de reduzir a dor associada a Ășlcera de perna, o paciente falcĂȘmico faz uso de opioides parenterais e enterais que normalmente estĂŁo associados a efeitos colaterais indesejados. Com o objetivo de reduzir o uso desses opioides sistĂȘmicos, avaliamos um gel de morfina, de fĂĄcil manipulação e baixo custo, que foi utilizado antes e apĂłs o processo de troca de curativo das Ășlceras de perna dos pacientes falcĂȘmicos atendidos em nossa instituição. Baseados na escala analĂłgica da dor foi avaliado o efeito analgĂ©sico do gel em 28 pacientes. Todos apresentavam dor grau 7 ou 8 antes da aplicação do gel. Vinte e quatro pacientes (85,7%) apresentaram total ausĂȘncia de dor por um perĂ­odo de 24 horas, nĂŁo sendo necessĂĄrio o uso de analgĂ©sicos sistĂȘmicos. Em trĂȘs pacientes (10,7%) a ausĂȘncia de dor durou um periodo de 12horas. Somente um paciente (3,6%) nĂŁo relatou analgesia apos o uso do gel. Os resultados demonstraram que o gel Ă© altamente eficaz no controle da dor das Ășlceras de perna de pacientes falcĂȘmicos.<br>Sickle cell disease is characterized by several clinical and pathophysiological changes including painful leg ulcers. These are difficult to heal and require the support of a multidisciplinary team in their management. The treatment of pain in these patients usually involves the use of opioids. In order to reduce the use of systemic opioids, we evaluated an easy-to-use low-cost morphine gel (0.12%) that was applied before and after changing leg ulcer dressings of sickle cell patients treated in Hemorio hospital. Based on the Analogue Pain Scale (APS) we evaluated the analgesic effect of the gel with 28 patients. All presented with a degree of pain of 7 or 8 before applying the gel. A total absence of pain was observed by 24 patients (85.7%) within thirty minutes of applying the gel, with the analgesia effect being maintained for a period of 24 hours and thus the use of other analgesics was not requiring. In 3 patients (10.7%) no pain was reported for a period of 12 hours. Only 1 patient (3.6%) reported no analgesic effect thirty minutes after the application of the gel. Our results indicate that the morphine gel was effective in controlling the pain of leg ulcers in this group of sickle cell patients. A controlled study should be designed to assess this important subject
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