2,036 research outputs found
Principais neoplasias cutâneas de pequenos animais
As neoplasias ocorrem pelo acúmulo progressivo de mutações no genoma celular que resultam em perda do controle de crescimento, diferenciação e morte celular. As neoplasias cutâneas têm um papel epidemiológico importante dentro da oncologia veterinária, pois a pele é o maior órgão do corpo e está em constante exposição a riscos e fatores oncogênicos, que associados podem favorecer o desenvolvimento de neoplasias. Neste sentido, objetivou-se realizar uma revisão de literatura acerca das principais neoplasias cutâneas na clínica de pequenos animais, facilitando assim o diagnóstico, o prognostico e até mesmo a qualidade de vida dos pacientes portadores das mesmas
Elaboração de um software para estimativas de população de árvores
Abstract. Digital image processing techniques associated with remote sensing technology through remotely piloted aircraft (RPAs) can be important tools in the forestry sector. The objective of this work was to develop a software module, based on the concept of local maximum filtering, to estimate a forest population through the identification of tree canopies in images obtained by RPA. The RGB (red, green and blue) were used for calculating brightness and the limit point was considered as the copies. The software module had a satisfactory performance for the prediction of crown counts in a forest area in Irati - PR, characterized by an accuracy of 86%. Resumo. As técnicas de processamento digital de imagem associadas a tecnologia de sensoriamento remoto por meio de aeronaves remotamente pilotadas (RPAs) podem ser importantes instrumentos no segmento florestal. Tendo em vista a necessidade de conhecimento do número de árvores em áreas de reflorestamento de pinus Taeda, este trabalho teve por objetivo o desenvolvimento de um módulo de software, baseado no conceito de filtragem de máximos locais, para estimar a população florestal através da identificação das copas das árvores em imagens obtidas por RPA. Foram utilizados os canais RGB (vermelho, verde e azul) para cálculo de brilho e considerou-se que as copas seriam o ponto de máximo deste. O módulo de software desenvolvido resultou em um desempenho satisfatório para predição de contagem de copas em uma área florestal localizada em Irati – PR, apresentando uma acurácia de 86%
Elaboração de um software para estimativas de população de árvores
Abstract. Digital image processing techniques associated with remote sensing technology through remotely piloted aircraft (RPAs) can be important tools in the forestry sector. The objective of this work was to develop a software module, based on the concept of local maximum filtering, to estimate a forest population through the identification of tree canopies in images obtained by RPA. The RGB (red, green and blue) were used for calculating brightness and the limit point was considered as the copies. The software module had a satisfactory performance for the prediction of crown counts in a forest area in Irati - PR, characterized by an accuracy of 86%. Resumo. As técnicas de processamento digital de imagem associadas a tecnologia de sensoriamento remoto por meio de aeronaves remotamente pilotadas (RPAs) podem ser importantes instrumentos no segmento florestal. Tendo em vista a necessidade de conhecimento do número de árvores em áreas de reflorestamento de pinus Taeda, este trabalho teve por objetivo o desenvolvimento de um módulo de software, baseado no conceito de filtragem de máximos locais, para estimar a população florestal através da identificação das copas das árvores em imagens obtidas por RPA. Foram utilizados os canais RGB (vermelho, verde e azul) para cálculo de brilho e considerou-se que as copas seriam o ponto de máximo deste. O módulo de software desenvolvido resultou em um desempenho satisfatório para predição de contagem de copas em uma área florestal localizada em Irati – PR, apresentando uma acurácia de 86%
Aberrant Water Homeostasis Detected by Stable Isotope Analysis
While isotopes are frequently used as tracers in investigations of disease physiology (i.e., 14C labeled glucose), few studies have examined the impact that disease, and disease-related alterations in metabolism, may have on stable isotope ratios at natural abundance levels. The isotopic composition of body water is heavily influenced by water metabolism and dietary patterns and may provide a platform for disease detection. By utilizing a model of streptozotocin (STZ)-induced diabetes as an index case of aberrant water homeostasis, we demonstrate that untreated diabetes mellitus results in distinct combinations, or signatures, of the hydrogen (δ2H) and oxygen (δ18O) isotope ratios in body water. Additionally, we show that the δ2H and δ18O values of body water are correlated with increased water flux, suggesting altered blood osmolality, due to hyperglycemia, as the mechanism behind this correlation. Further, we present a mathematical model describing the impact of water flux on the isotopic composition of body water and compare model predicted values with actual values. These data highlight the importance of factors such as water flux and energy expenditure on predictive models of body water and additionally provide a framework for using naturally occurring stable isotope ratios to monitor diseases that impact water homeostasis
Compressed representation of a partially defined integer function over multiple arguments
In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one
Beach sand and the potential for infectious disease transmission: observations and recommendations
An experimentally supported model of the Bacillus subtilis global transcriptional regulatory network
Organisms from all domains of life use gene regulation networks to control cell growth, identity, function, and responses to environmental challenges. Although accurate global regulatory models would provide critical evolutionary and functional insights, they remain incomplete, even for the best studied organisms. Efforts to build comprehensive networks are confounded by challenges including network scale, degree of connectivity, complexity of organism–environment interactions, and difficulty of estimating the activity of regulatory factors. Taking advantage of the large number of known regulatory interactions in Bacillus subtilis and two transcriptomics datasets (including one with 38 separate experiments collected specifically for this study), we use a new combination of network component analysis and model selection to simultaneously estimate transcription factor activities and learn a substantially expanded transcriptional regulatory network for this bacterium. In total, we predict 2,258 novel regulatory interactions and recall 74% of the previously known interactions. We obtained experimental support for 391 (out of 635 evaluated) novel regulatory edges (62% accuracy), thus significantly increasing our understanding of various cell processes, such as spore formation
Glial contribution to excitatory and inhibitory synapse loss in neurodegeneration
Synapse loss is an early feature shared by many neurodegenerative diseases, and it represents the major correlate of cognitive impairment. Recent studies reveal that microglia and astrocytes play a major role in synapse elimination, contributing to network dysfunction associated with neurodegeneration. Excitatory and inhibitory activity can be affected by glia-mediated synapse loss, resulting in imbalanced synaptic transmission and subsequent synaptic dysfunction. Here, we review the recent literature on the contribution of glia to excitatory/inhibitory imbalance, in the context of the most common neurodegenerative disorders. A better understanding of the mechanisms underlying pathological synapse loss will be instrumental to design targeted therapeutic interventions, taking in account the emerging roles of microglia and astrocytes in synapse remodeling
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