Feira de Ciências e Ensino por Projetos: uma Experiência Educativa no Norte do Brasil

O objetivo do trabalho foi verificar quais contribuições que a feira de ciências propiciou na aprendizagem dos estudantes da Escola Estadual Presidente Costa e Silva (Gurupi – Tocantins) a partir da elaboração de projetos, além de identificar quais relações permearam essa aprendizagem. Todo o desenvolvimento dos trabalhos foi baseado na pesquisa participante. Os resultados da aplicação do questionário aos estudantes mostraram que a metodologia via projetos possibilitou a aquisição de diversos conhecimentos para elaborar, planejar e executar projetos voltados a problemas ambientais presentes no cotidiano. Ademais, observaram-se fortes características de interdisciplinaridade e contextualização em todos os projetos.  Assim, acredita-se que a realização de eventos deste tipo possa favorecer o desenvolvimento de muitas habilidades e competências, além de ser um espaço descontraído e agradável para expositores e visitantes, podendo ser classificado como um espaço não formal de educação

Leishmania amazonensis promastigotes present two distinct modes of nucleus and kinetoplast segregation during cell cycle.

Abstract: Here, we show the morphological events associated with organelle segregation and their timing in the cell cycle of a reference strain of Leishmania (L.) amazonensis promastigotes, the main causative agent of Tegumentary leishmaniasis in the Americas. We show evidences that during the cell cycle, L. amazonensis promastigotes present two distinct modes of nucleus and kinetoplast segregation, which occur in different temporal order in different proportions of cells. We used DAPI-staining and EdU-labeling to monitor the segregation of DNA-containing organelles and DNA replication in wild-type parasites. The emergence of a new flagellum was observed using a specific monoclonal antibody. The results show that L. amazonensis cell cycle division is peculiar, with 65% of the dividing cells duplicating the kinetoplast before the nucleus, and the remaining 35% doing the opposite or duplicating both organelles concomitantly. In both cases, the new flagellum appeared during S to G2 phase in 1N1K cells and thus before the segregation of both DNA-containing organelles; however, we could not determine the exact timing of flagellar synthesis. Most of these results were confirmed by the synchronization of parasites using hydroxyurea. Altogether, our data show that during the cell cycle of L. amazonensis promastigotes, similarly to L. donovani, the segregation of nucleus and kinetoplast do not follow a specific order, especially when compared to other trypanosomatids, reinforcing the idea that this characteristic seems to be species-specific and may represent differences in cellular biology among members of the Leishmania genus

Pervasive gaps in Amazonian ecological research

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

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

Pervasive gaps in Amazonian ecological research

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

Development and economic analysis of 1G2G integrated biorefinery models using dilute acid pretreatment

O etanol é um dos biocombustíveis oriundos de fontes renováveis mais promissor e ambientalmente amigável. Visando-se ao atendimento de uma demanda crescente por este álcool, o aproveitamento integral dos materiais lignocelulósicos é uma alternativa interessante e, desta forma, trabalhos de pesquisa têm sido desenvolvidos visando-se à viabilização de biorrefinarias de produção integrada de etanol 1G e 2G. O presente trabalho teve como objetivo principal desenvolver e analisar economicamente modelos de biorrefinaria integrada 1G2G que empregam pré-tratamento ácido diluído, avaliando-se o impacto econômico do destino da hemicelulose para produção de etanol. Para isso, foram definidos cenários que incluíssem todas as etapas do processo de produção de etanol 1G e 2G, sendo avaliados dois teores de sólidos no reator de pré-tratamento (5% e 10%) e, para cada caso, três relações tempo e conversão da hidrólise enzimática, sendo estas de 45%, 51% e 55% para tempos de reação de 24h, 48h e 72h, respectivamente. Para cada condição, considerou-se a fermentação de pentose (C5) ou seu envio para tratamento de efluentes, constituindo-se, assim, 12 cenários. Foram realizadas as simulações destes cenários auxiliadas pelo pacote computacional Aspen Plus®, obtendo-se os dados de balanço de massa e energia, permitindo assim a realização da análise de viabilidade econômica empregando a plataforma Biorrefinaria Virtual de Cana - BVC. Foi possível observar que a produção de etanol 2G empregando pré-tratamento ácido diluído foi responsável por um aumento na produção de etanol de até 35%. Avaliando-se os cenários, observou-se que quando o reator de pré-tratamento foi operado com maior teor de sólidos, menor consumo de energia térmica foi necessário, requerendo menor quantidade de bagaço na caldeira e aumentando o rendimento final de etanol. Com relação ao custo de investimento, este correspondeu a R$799,2 milhões para a biorrefinaria 1G, enquanto que os cenários integrados 1G2G apresentaram valores cerca de 40$ 799.2 million for 1G biorefinery, compared to a value 40% higher observed for integrated 1G2G scenarios. Among the most significant areas of investment cost are the pretreatment and the generation and distribution of steam. With relation to the cost of etanol production, scenarios that presented the lowest value for 2G ethanol corresponded to the use of 10% solids in the pre-treatment reactor associated to C5 fermentation. The most significant areas for this cost were the input and capital costs. However, the scenarios with 5% solids in the pre-treatment reactor without C5 fermentation resulted in a lower global ethanol production cost (1G2G), with sugarcane, chemical inputs and capital cost representing the most significant fraction. Based on the internal rate of return, this was lower than the minimum attractiveness rate of return for all scenarios, resulting in a negative net present value, allowing inferring that, under the evaluated conditions, the methodology used in the scenarios would be unviable from an investor viewpoint. However, the economic analysis helped to identify technological bottlenecks of the integrated 1G2G etanol production process using dilute acid pretreatment, favoring the definition of operational goals to be solved in research works

Economic sustainability assessment of 1G2G integrated biorefineries with xylan and lignosulfonate co-production

As biorrefinarias surgem como matrizes industriais de processos sustentáveis com objetivo de empregar fontes renováveis na geração de bioprodutos. Essa abordagem renovável, no entanto, precisa ser atraente economicamente para que efetivamente substitua os processos não-renováveis. Assim, o presente trabalho teve como objetivo principal avaliar a sustentabilidade econômica de cenários de biorrefinarias integradas de produção de etanol 1G, etanol 2G e eletricidade, com a coprodução, individual e simultânea, de xilana e lignossulfonato, empregando cana-de-açúcar como matéria-prima. Para isso, foram definidos setes cenários, que incluíram a produção de etanol 1G e sua integração com a produção de etanol 2G, com subsequente integração da coprodução dos bioproduto, xilana e lignossulfonatos, tanto individualmente quanto simultaneamente. Para os cenários com produção de xilana, dois métodos de extração foram considerados, um por via biológica (enzimática) e outro por via química (hidróxido de sódio). Foram realizadas as simulações dos cenários com auxílio do software Aspen Plus®, obtendo-se os dados de balanço de massa e energia e, subsequentemente, sendo realizada a avaliação de sustentabilidade econômica. Para as xilanas, foi calculado o preço mínimo de venda (PMV) por meio de uma análise incremental. O rendimento da produção de etanol anidro e eletricidade excedente variaram de 81,1 a 105,87 L/TC e de 83 a 189,2 kWh/TC, respectivamente. Já a xilana e o lignossulfonatos tiveram rendimentos de 8,1 a 98,3 kg/TC e de 8,5 a 15,6 kg/TC, respectivamente. A coprodução individual de xilana na biorrefinaria 1G2G apresentou redução de 2,17% e 17,5% no rendimento de etanol e um aumento de 0% e 39,5% no excedente de eletricidade nas formas de extração enzimática e química, respectivamente. A fração de bagaço queimado foi largamente maior quando se empregou a via química para produção de xilana, resultado do maior consumo energético. A coprodução de lignossulfonatos na biorrefinaria 1G2G teve comportamento similar. Entretanto, os cenários com coprodução simultânea de xilana e lignossulfonatos apresentaram maiores vantagens sobre os cenários isolados. Com relação aos custos com investimento, a produção de xilana por via enzimática foi quase 4,5 vezes maior em comparação ao cenário da xilana obtida por via química. No cenário em que a taxa interna de retorno (TIR) correspondeu a 12% ao ano (valor presente líquido (VPL)=0), o PMV da xilana foi de R$0,35 e R$4,38 para a produção por via enzimática e química, respectivamente. Para a coprodução de lignossulfonato, alcançou-se uma TIR anual de 13,22%, acompanhada de um VPL de aproximadamente R$92 milhões. Entretanto, melhores perspectivas econômicas foram alcançadas quando houve a coprodução simultânea dos bioprodutos, ao observar reduções de 77$0.35 and R$4.38 for enzymatic and chemical production, respectively. Approximately 13.22$92 million NPV. However, better economic prospects were achieved when there were simultaneous coproduction bioproducts, resulting in 77% and 14% reductions in MSP for enzymatic and chemical xylans, respectively. The contribution of xylan and lignosulfonate co-production in biorefineries with 1G2G ethanol integrated production, utilizing the alkaline sulfite method as biomass pretreatment, was evident. Better economic performance can be achieved by integrating co-products with higher added value, which results also in fostering the bioeconomy. Furthermore, the analysis allowed the technological bottlenecks identification, as well as the operational goals definition, to be addressed in future research

Patient-ventilator asynchrony

ABSTRACT Patient-v entilator asynchrony (PVA) is a mismatch between the patient, regarding time, flow, volume, or pressure demands of the patient respiratory system, and the ventilator, which supplies such demands, during mechanical ventilation (MV). It is a common phenomenon, with incidence rates ranging from 10% to 85%. PVA might be due to factors related to the patient, to the ventilator, or both. The most common PVA types are those related to triggering, such as ineffective effort, auto-triggering, and double triggering; those related to premature or delayed cycling; and those related to insufficient or excessive flow. Each of these types can be detected by visual inspection of volume, flow, and pressure waveforms on the mechanical ventilator display. Specific ventilatory strategies can be used in combination with clinical management, such as controlling patient pain, anxiety, fever, etc. Deep sedation should be avoided whenever possible. PVA has been associated with unwanted outcomes, such as discomfort, dyspnea, worsening of pulmonary gas exchange, increased work of breathing, diaphragmatic injury, sleep impairment, and increased use of sedation or neuromuscular blockade, as well as increases in the duration of MV, weaning time, and mortality. Proportional assist ventilation and neurally adjusted ventilatory assist are modalities of partial ventilatory support that reduce PVA and have shown promise. This article reviews the literature on the types and causes of PVA, as well as the methods used in its evaluation, its potential implications in the recovery process of critically ill patients, and strategies for its resolution

Doença pulmonar por metal duro em trabalhador da indústria petrolífera

A doença pulmonar por metal duro é uma pneumonia intersticial por células gigantes relacionada com a exposição à poeira composta por metais duros. Neste artigo é relatado o caso de um profissional da indústria petrolífera, diagnosticado com doença pulmonar por metal duro com base na documentação clínica, radiológica, funcional pulmonar e anatomopatológica