29 research outputs found

    Defect Engineering in Reduced Graphene Oxide toward Advanced Energy Conversion

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    Defect engineering in reduced graphene oxide (rGO) for a smart design of fuel-cell supports has become an effective approach to improve the restricted two-dimensional (2D) mass and charge transfer and to boost the alcohol oxidation reaction. The present mini-review describes recent trends across prominent characteristics of tailored reduced graphene oxides, which include but are not restricted to, engineered three-dimensional (3D) nanostructures for better mass transport, tuned electron/hole conduction for easier electrical transport, and hybridized surfaces for high electrocatalytic activity. Special focus fixes upon the experimental progress on defect engineering, from three-dimensional structure assembly to surface metal complexation and heteroatom doping to size-controlled defect formation. Given their crucial impact on reduced graphene oxide properties, controlled methods for synthesis, and processing offer considerable promise toward next-generation carbon nanomaterials for electrocatalysis

    Biomimetics and composite materials toward efficient mobility: a review

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    The development of new materials has always been strictly related to the rise of new technologies and progressively efficient systems. However, cutting-edge materials might not be enough to ensure the effectiveness of a given product if the design guidelines used do not favor the specific advantages of this material. Polymeric composites are known for their excellent mechanical properties, but current manufacturing techniques and the relatively narrow expertise in the field amongst engineers impose the challenge to provide the most suitable designs to certain applications. Bio-inspired designs, supported by thousands of years of evolution of nature, have shown to be extremely profitable tools for the design of optimized yet structurally complex shapes in which the tailoring aspect of polymeric composites perfectly fit. Bearing in mind the current but old-fashioned designs of auto-parts and vehicles built with metals with little or no topological optimization, the present work addresses how biomimicry is being applied in the mobility industry nowadays to provide lightweight structures and efficient designs. A general overview of biomimicry is made regarding vehicles, approaching how the use of composite materials has already contributed to successful cases

    Análise comparativa das abordagens cirúrgicas no tratamento de cardiopatias

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    Em análise a evolução histórica e as inovações na cirurgia cardíaca, este estudo objetiva analisar comparativamente as abordagens cirúrgicas no tratamento de cardiopatias, destacando a transição das técnicas tradicionais de cirurgia aberta para métodos minimamente invasivos como a videolaparoscopia e a cirurgia robótica. Para tanto, procede-se à uma revisão narrativa da literatura, explorando uma gama extensiva de estudos e relatos científicos que ilustram os avanços tecnológicos e seus impactos nos resultados clínicos. Desse modo, observa-se que as técnicas minimamente invasivas oferecem benefícios substanciais, como redução no tempo de recuperação, diminuição do trauma cirúrgico, e menores taxas de complicações e mortalidade perioperatória em comparação com a cirurgia aberta. Estes resultados permitem concluir que a cirurgia minimamente invasiva representa um avanço significativo na prática cardiológica, proporcionando procedimentos mais seguros e eficazes, com menor impacto para os pacientes e melhores prognósticos a longo prazo. Para futuras pesquisas, sugere-se o aprofundamento na análise dos resultados a longo prazo e na integração de novas tecnologias, como inteligência artificial e realidade aumentada, para otimizar ainda mais as práticas cirúrgicas e expandir as possibilidades de tratamento das cardiopatias

    ANÁLISE COMPARATIVA DO USO DA ESTATINA E DO ÁCIDO NICOTÍNICO NO TRATAMENTO DA SÍNDROME METABÓLICA

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    Considering metabolic syndrome (MS) as a pathophysiological condition characterized by arterial hypertension, central obesity, insulin resistance, dyslipidemia, and hyperglycemia, this study aims to compare the use of statins and nicotinic acid in the treatment of MS. To this end, a comparative analysis based on relevant clinical and epidemiological studies was conducted. Thus, it is observed that statins significantly reduce LDL cholesterol by about 50% and decrease the risk of cardiovascular events by 25% to 35%, with an odds ratio (OR) of improvement between 0.70 and 0.80. Statins are widely available and accessible, especially in generic versions, and have a relatively manageable adverse effect profile. In contrast, nicotinic acid reduces LDL cholesterol by 15% to 25%, increases HDL cholesterol, and reduces triglycerides, but with less consistent efficacy in preventing cardiovascular events (OR ranging from 0.90 to 1.10) and significant side effects, such as skin flushing and hepatotoxicity. The cost and availability of nicotinic acid are more limited compared to statins. It is concluded that statins are the preferred choice for the treatment of MS due to their robust efficacy and accessibility, while nicotinic acid may be considered in specific cases, with caution due to its adverse effects.Considerando a síndrome metabólica (SM) como uma condição fisiopatológica caracterizada por hipertensão arterial, obesidade central, resistência à insulina, dislipidemia e hiperglicemia, este estudo objetiva comparar o uso de estatinas e ácido nicotínico no tratamento da SM. Para tanto, procede-se a uma análise comparativa baseada em estudos clínicos e epidemiológicos relevantes. Desse modo, observa-se que as estatinas reduzem significativamente o LDL-colesterol em cerca de 50% e diminuem o risco de eventos cardiovasculares em 25% a 35%, com odds ratio (OR) de melhora entre 0,70 e 0,80. As estatinas são amplamente disponíveis e acessíveis, especialmente nas versões genéricas, e apresentam um perfil de efeitos adversos relativamente manejável. Em contraste, o ácido nicotínico reduz o LDL-colesterol em 15% a 25%, aumenta o HDL-colesterol e reduz os triglicerídeos, mas com uma eficácia menos consistente na prevenção de eventos cardiovasculares (OR variando de 0,90 a 1,10) e efeitos colaterais significativos, como rubor cutâneo e hepatotoxicidade. O custo e a disponibilidade do ácido nicotínico são mais limitados em comparação às estatinas. Conclui-se que as estatinas são a escolha preferida para o tratamento da SM devido à sua eficácia robusta e acessibilidade, enquanto o ácido nicotínico pode ser considerado em casos específicos, com precaução devido aos seus efeitos adversos

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    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

    Leucemia Linfoblástica Aguda (LLA) na população pediátrica: marcadores moleculares e implicações terapêuticas

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    A Leucemia Linfoblástica Aguda (LLA) é uma forma comum de câncer pediátrico, representando cerca de 80% dos casos de leucemia em crianças. A patologia é caracterizada pela proliferação descontrolada de células-tronco hematopoéticas na medula óssea, e avanços recentes na pesquisa genômica têm proporcionado uma compreensão mais profunda da complexidade molecular subjacente à doença. O presente estudo tem como objetivo oferecer uma visão abrangente dos principais marcadores moleculares e implicações terapêuticas associadas à LLA na população pediátrica. Este estudo, baseado em uma revisão sistemática da literatura científica, abrange o período de 2013 a 2023, utilizando as bases de dados PubMed (Medline), Cochrane Library e Scientific Electronic Library Online (SciELO). Marcadores moleculares preponderantes, como rearranjos cromossômicos específicos (t(12;21), t(1;19), t(9;22)), mutações genéticas distintivas (ETV6-RUNX1, E2A-PBX1, TP53) e amplificação do gene BCR-ABL1, têm sido objeto de estudo aprofundado. Esses marcadores desempenham um papel crucial na estratificação de risco e prognóstico, permitindo uma abordagem mais personalizada no tratamento da LLA em crianças. As implicações terapêuticas derivadas desses marcadores são vastas, destacando a promissora era das terapias direcionadas. Terapias específicas para mutações, como aquelas direcionadas à mutação BCR-ABL1, e inovações em imunoterapia estão moldando o cenário do tratamento da LLA, proporcionando resultados mais eficazes e menos tóxicos. Os resultados destacam a eficácia das terapias direcionadas e a necessidade contínua de pesquisa para otimizar a intervenção terapêutica, melhorar a qualidade de vida dos pacientes pediátricos afetados pela LLA e explorar novas facetas do tratamento. Em conclusão, este artigo fornece uma análise aprofundada dos marcadores moleculares e terapias associadas à LLA na população pediátrica, destacando avanços significativos e delineando áreas para investigação futura

    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

    Pervasive gaps in Amazonian ecological research

    Get PDF
    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
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