Zebrafish tracking using YOLOv2 and Kalman filter Barreiros, Marta de Oliveira; Dantas, Diego de Oliveira; Silva, Luís Claudio de Oliveira ...
Scientific reports,
02/2021, Letnik:
11, Številka:
1
Journal Article
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Fish show rapid movements in various behavioral activities or associated with the presence of food. However, in periods of rapid movement, the rate at which occlusion occurs among the fish is quite ...high, causing inconsistency in the detection and tracking of fish, hindering the fish's identity and behavioral trajectory over a long period of time. Although some algorithms have been proposed to solve these problems, most of their applications were made in groups of fish that swim in shallow water and calm behavior, with few sudden movements. To solve these problems, a convolutional network of object recognition, YOLOv2, was used to delimit the region of the fish heads to optimize individual fish detection. In the tracking phase, the Kalman filter was used to estimate the best state of the fish's head position in each frame and, subsequently, the trajectories of each fish were connected among the frames. The results of the algorithm show adequate performances in the trajectories of groups of zebrafish that exhibited rapid movements.
Scholars have extensively investigated public value creation and appropriation concerning public services delivered strictly by the government and public–private arrangements, such as public–private ...partnerships (PPPs). However, such studies often focus on value for money and economic performance criteria. This study examines how public value can be created and appropriated in PPP settings and how public value mechanisms can influence these phenomena. Considering that the literature lacks an integrated and structured analytical framework to assess such phenomena, this conceptual article addresses four mainstream PPP topics regarding public value mechanisms (information sharing, public and private capabilities, risk governance, and stakeholder orientation), which can be associated with PPPs' public value creation (destruction) and appropriation (misappropriation). Thus, this article highlights a need to evaluate PPPs in terms of public value creation beyond the economic performance criteria and fills the literature gap by proposing a public value creation and appropriation framework.
O artigo busca entender o sentido do sintagma experimentum linguaepresente em textos escritos pelo filósofo italiano Giorgio Agamben entre os anos 1989-1990. O artigo escolhe dois desses textos (uma ...introdução a uma edição italiana de um livro de Ingeborg Bachmann e um prefácio à edição francesa do livro Infância e história, ambos de 1989) para pensar em que medida a expressão experimentum linguaese apresenta como essencial para entender como a questão do indizível se apresenta tanto à poesia quanto à filosofia. Com o sintagma experimentum linguae, Agamben vem propor uma outra experiência da linguagem a partir da qual tenta desconstruir a ideia de indizível. Para isso, ele estabelece um diálogo não só com a poeta austríaca Ingeborg Bachmann, mas também com filósofos como Heidegger, Wittgenstein e Benjamin.
With nearly 1,100 species, the fish family Characidae represents more than half of the species of Characiformes, and is a key component of Neotropical freshwater ecosystems. The composition, ...phylogeny, and classification of Characidae is currently uncertain, despite significant efforts based on analysis of morphological and molecular data. No consensus about the monophyly of this group or its position within the order Characiformes has been reached, challenged by the fact that many key studies to date have non-overlapping taxonomic representation and focus only on subsets of this diversity.
In the present study we propose a new definition of the family Characidae and a hypothesis of relationships for the Characiformes based on phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes (4,680 base pairs). The sequences were obtained from 211 samples representing 166 genera distributed among all 18 recognized families in the order Characiformes, all 14 recognized subfamilies in the Characidae, plus 56 of the genera so far considered incertae sedis in the Characidae. The phylogeny obtained is robust, with most lineages significantly supported by posterior probabilities in Bayesian analysis, and high bootstrap values from maximum likelihood and parsimony analyses.
A monophyletic assemblage strongly supported in all our phylogenetic analysis is herein defined as the Characidae and includes the characiform species lacking a supraorbital bone and with a derived position of the emergence of the hyoid artery from the anterior ceratohyal. To recognize this and several other monophyletic groups within characiforms we propose changes in the limits of several families to facilitate future studies in the Characiformes and particularly the Characidae. This work presents a new phylogenetic framework for a speciose and morphologically diverse group of freshwater fishes of significant ecological and evolutionary importance across the Neotropics and portions of Africa.
•Amazonian toxoplasmosis manifests severe symptoms in immunosuppressed patients.•The disease can spread throughout Brazil.•There is a need for greater knowledge to improve diagnosis and treatment.
A resorcinarene derivative of vanillin, resvan, was synthesized and characterized by spectroscopic techniques. We measured the cytotoxicity (in vivo and in vitro), antioxidant and anti-Toxoplasma ...activities of vanillin and the resorcinarene compound. Here we show that vanillin has a dose-dependent behavior with IC50 of 645 µg/mL through an in vitro cytotoxicity assay. However, we could not observe any cytotoxic response at higher concentrations of resvan (IC50 > 2,000 µg/mL). The in vivo acute toxicity assays of vanillin and resvan exhibited a significant safety margin indicated by a lack of systemic and behavioral toxicity up to 300 mg/kg during the first 30 min, 24 h or 14 days after administration. The obtained derivative showed greater antioxidative activity (84.9%) when comparing to vanillin (19.4%) at 1,000 μg/mL. In addition, vanillin presents anti-Toxoplasma activity, while resvan does not show that feature. Our findings suggest that this particular derivative has an efficient antioxidant activity and a negligible cytotoxic effect, making it a potential target for further biological investigations.
Monkeypox: A looming concern for children? Oliveira, Claudio; Araújo Andrade, Joelma; Oliveira, Jonas
Asian Pacific journal of tropical medicine,
08/2022, Letnik:
15, Številka:
8
Journal Article
This article analyzes the role of access to digital and physical forms of finance on income inequality. The article develops a new measure of financial access that captures the relationship between ...digital finance and inequality, using a dynamic panel data analysis on 116 countries between 2001 and 2019. The results indicate that access to both financial institutions and digital access may reduce inequality, suggesting that they are complementary. We also find evidence suggesting that, in emerging economies, access to digital financial is more relevant than physical access.
•This article analyzes the role of financial access to digital and physical forms of finance on income inequality.•This article develops a new measure of financial access that can capture the impact of digital finance on inequality.•A dynamic panel data analysis of 116 countries between 2001 and 2019 assesses the impact of financial access on inequality.•The findings suggest that both physical and digital access reduce inequality, showing complementarity between the two.•We also find evidence suggesting that digital financial access has a bigger impact than physical access in emerging economies.
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