69 research outputs found
Hybrid Optimization Process Applied to Tuning of Dynamic Matrix Control: Study Case with DC Motor
This paper presents study about Dynamic Matrix Control (DMC) controller applied to speed control of DC motor. DMC controller parameters (prediction horizon, control horizon and damping rate of reference) are obtained through optimization methods employing heuristic, deterministic and hybrid strategies. The use of advanced control technique combined with using of optimization methods aims to achieve highly efficient control, reducing the transient state period and variations in steady state. These methods were applied on a simulation model in order to verify which one provides better control results.
Index Terms—Predictive Control, Deterministic Optimization, Heuristic Optimization, Hybrid Optimization, DC motor
A importância do diagnóstico laboratorial para erradicação da malária: uma revisão de literatura / The importance of laboratory diagnosis for malaria eradication: a literature review
A malária é uma doença causada por parasitas do gênero Plasmodium, sendo transmitida aos humanos pela picada de uma fêmea infectada do mosquito da espécie Anopheles. No Brasil, principalmente na região Amazônica, é um dos principais problemas de saúde pública. Porém, também ocorrem casos de malária em regiões extra-amazônica. A malária é uma das principais causas de mortalidade mundialmente e o diagnóstico precoce e rápido impedem uma maior letalidade. Assim, o objetivo do trabalho é realizar uma revisão de literatura sobre a importância do diagnóstico laboratorial para erradicação da malária. Os artigos utilizados nesta revisão de literatura foram pesquisados nas bases de dados National Library of Medicine (PubMED), Google Acadêmico e Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), sendo publicados entre os anos 2004 e 2021. O laboratório é necessário para o diagnóstico da malária, que começa com a identificação do parasita, através do exame microscópio do sangue que pode ser realizado de dois tipos: esfregaço delgado (distendido) ou espesso (gota espessa), sendo o último o mais utilizado. Ambos os métodos apresentam baixo custo, identificando com facilidade e exatidão a espécie do plasmódio. Além disso, técnicas mais precisas como a Reação de Cadeia em Polimerase (PCR) são utilizadas para a identificação do DNA do Plasmodium circulante, porém essa técnica tem um elevado custo e por isso, não é muito utilizada na rotina de diagnóstico laboratorial dos casos de malária, apenas em centros de pesquisa
Effects of salinity on the physiology of Salvinia auriculata Aubl. (Salviniales, Pteridophyta)
Salvinia auriculata Aubl. is reported to occur in different zones of the Capibaribe River, Pernambuco State, Brazil. This river varies in salinity in different areas. This study evaluated the growth, photosynthesis and pigment contents of S. auriculata at different salinity levels. Plant sections were collected in the Cursaí Reservoir, located in the municipality of Paudalho, Pernambuco, and were brought to a greenhouse, where they were put in glass flasks filled with 250 mL of liquid, placed on benches. The plants were exposed for 40 h to salinity levels of 0, 17 and 34, obtained with reservoir freshwater, 1:1 freshwater:seawater and pure seawater, respectively. At the end of the experimental period, the plants in salt water showed color changes, with brownish leaves. In addition, plant growth rates decreased. Salinity and time had a negative influence on photosynthetic responses such as Fv/Fm, ETRmax and ETR, which showed reductions under the highest salinity treatment. Response patterns may help to explain S. auriculata occurrence, and its distribution can be regulated by salinity
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
Consistent patterns of common species across tropical tree communities
Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe
The Genome of Anopheles darlingi, the main neotropical malaria vector
Anopheles darlingi is the principal neotropical malaria vector, responsible for more than a million cases of malaria per year on the American continent. Anopheles darlingi diverged from the African and Asian malaria vectors ∼100 million years ago (mya) and successfully adapted to the New World environment. Here we present an annotated reference A. darlingi genome, sequenced from a wild population of males and females collected in the Brazilian Amazon. A total of 10 481 predicted protein-coding genes were annotated, 72% of which have their closest counterpart in Anopheles gambiae and 21% have highest similarity with other mosquito species. In spite of a long period of divergent evolution, conserved gene synteny was observed between A. darlingi and A. gambiae. More than 10 million single nucleotide polymorphisms and short indels with potential use as genetic markers were identified. Transposable elements correspond to 2.3% of the A. darlingi genome. Genes associated with hematophagy, immunity and insecticide resistance, directly involved in vectorhuman and vectorparasite interactions, were identified and discussed. This study represents the first effort to sequence the genome of a neotropical malaria vector, and opens a new window through which we can contemplate the evolutionary history of anopheline mosquitoes. It also provides valuable information that may lead to novel strategies to reduce malaria transmission on the South American continent. The A. darlingi genome is accessible at www.labinfo.lncc.br/index.php/anopheles- darlingi. © 2013 The Author(s)
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