2,558 research outputs found
Cluster-based semi-supervised ensemble learning
Semi-supervised classification consists of acquiring knowledge from both labelled and unlabelled data to classify test instances. The cluster assumption represents one of the potential relationships between true classes and data distribution that semi-supervised algorithms assume in order to use unlabelled data. Ensemble algorithms have been widely and successfully employed in both supervised and semi-supervised contexts. In this Thesis, we focus on the cluster assumption to study ensemble learning based on a new cluster regularisation technique for multi-class semi-supervised classification. Firstly, we introduce a multi-class cluster-based classifier, the Cluster-based Regularisation (Cluster- Reg) algorithm. ClusterReg employs a new regularisation mechanism based on posterior probabilities generated by a clustering algorithm in order to avoid generating decision boundaries that traverses high-density regions. Such a method possesses robustness to overlapping classes and to scarce labelled instances on uncertain and low-density regions, when data follows the cluster assumption. Secondly, we propose a robust multi-class boosting technique, Cluster-based Boosting (CBoost), which implements the proposed cluster regularisation for ensemble learning and uses ClusterReg as base learner. CBoost is able to overcome possible incorrect pseudo-labels and produces better generalisation than existing classifiers. And, finally, since there are often datasets with a large number of unlabelled instances, we propose the Efficient Cluster-based Boosting (ECB) for large multi-class datasets. ECB extends CBoost and has lower time and memory complexities than state-of-the-art algorithms. Such a method employs a sampling procedure to reduce the training set of base learners, an efficient clustering algorithm, and an approximation technique for nearest neighbours to avoid the computation of pairwise distance matrix. Hence, ECB enables semi-supervised classification for large-scale datasets
Selection and optimization of extracellular lipase production using agro-industrial waste
The aim of this study was to isolate and select lipase-producing microorganisms originated from different substrates, as well as to optimize the production of microbial lipase by submerged fermentation under different nutrient conditions. Of the 40 microorganisms isolated, 39 showed a halo around the colonies and 4 were selected (Burkholderia, Bacillus sp., Penicillium lanosum and Corynebac glutamyl), where strains showing lipolytic halo Radius (R) / colony radius (r) ratio greater than 2.0 were selected. The results of submerged fermentation expressed as enzymatic activity revealed that the genera of microorganisms significantly influenced the enzymatic reaction, and lipase obtained from Burkholderia cepacia was the most promising, with activity of 0.0058 U.mL-1. It was also observed in the optimization step of lipase production that the sodium nitrate content (NaNO3) had a positive effect on enzyme production, and its increase was indicative of higher enzymatic activity. The addition of sources of organic nitrogen (corn steep liquor, p = 0.2398), carbon (soybean oil, p = 0.3379), magnesium MgSO4.7H2O (p = 0.4189) and potassium KH2PO4 (p = 0.8562) had no significant effects on the lipase production and could result in decreased production of extracellular lipases.Keywords: Burkholderia cepacia, hydrolytic enzymes, residue, submerged fermentationAfrican Journal of Biotechnology, Vol. 13(4), pp. 566-573, 22 January, 201
Interação e convergência midiática: storytelling no comercial da Apple
This work is a partial result of the Prolim Study Group - Processes and Languages of Media Images - CNPq, qualitative research whose main object of study is the soundtrack of the 2018 Christmas commercial from Apple, entitled “Share Your Gifts”, analyzing your media interaction with the consumer from the production and distribution in storytelling. The use of the storytelling format in his 2018 Christmas commercial, employed a soundtrack that is highlighted as an emotional connection between the brand and the subject, which contributes to their market relations, something that leads us to verify the interference and attention generated in the interlocutors from the soundtrack used. We started with the discourse analysis method, we verified through the analysis of this video that the way the interlocutors transmit a message intervenes directly in the story told by the company, that way, we perceive the need to understand the techniques used by storytelling in the campaign, as well as media and marketing practices to strengthen the brand, direct influence on the relationship between subject and means of communication. In this exchange in the means of communication, we also take into account emotional issues - these present in this storytelling soundtrack, which is part of this globalized communication trend; at the same time, we verify the message in its dissemination format that stands out among the big brands and their media influences. We realize that the use of storytelling has become one of the means of communicational convergence of major brands, they tend to focus on media interaction with the subject and to leverage the positioning of these brands in the market, it was found that the current consumer has also become the spokesperson for online dissemination - an active consumer, directly influencing these mediations of messages.El presente trabajo es un resultado parcial del Grupo de estudio Prolim - Procesos e idiomas de las imágenes de los medios - CNPq, cuyo principal objeto de estudio es la banda sonora del comercial navideño de 2018 de Apple, titulado “Share Your Gifts” - traducción “Comparte tus regalos”, analizando la interacción de los medios con el consumidor desde la producción y distribución en storytelling. El uso del formato Storytelling en su comercial navideño de 2018 empleó una banda sonora que se destaca como una conexión emocional entre la marca y el sujeto, lo que contribuye a sus relaciones con el mercado, algo que nos lleva a constatar la interferencia y atención que se les presta a nuestros interlocutores desde la banda sonora utilizada. Comenzamos con el método de análisis del discurso, comprobamos a través del análisis de este video que la forma en que los interlocutores transmiten un mensaje interviene directamente en la historia contada por la empresa, de esta manera, nos damos cuenta de que es necesario entender las técnicas utilizadas en storytelling en la campaña, así como las prácticas mediáticas. y marketing para fortalecer la marca, influencia directa en la relación entre sujeto y medio. En este intercambio de medios de comunicación también se tienen en cuenta cuestiones emocionales, presentes en esta banda sonora de la narración, que forma parte de esta corriente comunicativa globalizada; al mismo tiempo, verificamos el mensaje en su formato de difusión que destaca entre las grandes marcas y sus influencias mediáticas. Entendemos que el uso del torytelling se ha convertido en uno de los medios de convergencia comunicacional de las grandes marcas, tienden a enfocarse en la interacción mediática con el tema y apalancar el posicionamiento de estas marcas en el mercado, además se descubrió que el consumidor actual también se ha convertido en el portavoz de la difusión en línea, un consumidor activo que influye directamente en estas mediaciones de mensajes. Este trabalho é resultado parcial do Grupo de Estudos Prolim - Processos e Linguagens das Imagens Mídias - CNPq, teve como objeto principal de estudo a trilha sonora do comercial natalino de 2018 da Apple, intitulado Share your gifts (“Compartilhe seus presentes”), a partir da qual se realiza uma análise de sua interação midiática com o consumidor a partir da produção e da distribuição no storytelling. A utilização do formato de storytelling em seu comercial natalino de 2018 empregou uma trilha sonora que é destacada como conexão emocional entre a marca e o sujeito, o que contribui para suas relações de mercado, algo que nos leva a verificar a interferência e atenção gerada nos interlocutores a partir da trilha sonora usada. Com base no método de análise do discurso, analisamos o referido comercial e verificamos a forma como os interlocutores transmitem a mensagem intervém diretamente na história contada pela empresa; desse modo, é necessária a compreensão das técnicas usadas do storytelling na campanha, como também as práticas midiáticas e mercadológicas para fortalecer a marca e influenciar diretamente na relação entre sujeito e meios de comunicação. Nesse intercâmbio dos meios de comunicação, também levamos em consideração as questões emocionais — presentes nessa trilha sonora do storytelling —, que fazem parte da tendência comunicacional globalizada; ao mesmo tempo, verificamos a mensagem em seu formato de divulgação que se destacada entre as grandes marcas e suas influências midiáticas. Apreendemos que o uso do storytelling se tornou um dos meios de convergências comunicacionais das grandes marcas, as quais tendem a focar a interação midiática com o sujeito e alavancar o seu posicionamento no mercado, a partir deste novo formado de consumidor, que se torna o porta voz da divulgação online - um consumidor ativo, influenciando diretamente nestas mediações das mensagens. 
POLÍTICAS PÚBLICAS E GESTÃO DEMOCRÁTICA: APONTAMENTOS PARA PENSAR A EDUCAÇÃO NO BRASIL
Este texto, construído a partir dos processos metodológicos de pesquisa bibliográfica e sistematização, aborda as relações que se podem estabelecer entre políticas públicas educacionais, gestão democrática e perspectivas para a educação no Brasil. Parte-se do suposto que as políticas públicas constituem-se em apontamentos para a educação, entre os quais destaca-se o princípio de gestão democrática. Entretanto, pensar a gestão democrática requer um conjunto de medidas audaciosas para as tentativas descentralizadoras de poder social, no contexto de políticas públicas neoliberais e implica três processos: a descentralização, a participação e a autonomia. Especialmente o último parecer ser o articulador dos demais, uma vez que a autonomia não acontece de forma absoluta e isolada, pois a mesma é regulada por normas provindas do Estado, que permite, através das políticas públicas educacionais, essa autonomia institucional na medida de seus interesses que são os mesmos do capital, se for considerado que o Estado brasileiro caracteriza-se como Estado mínimo. Ainda assim, o texto aponta a gestão democrática como uma possibilidade para uma educação com mais qualidade
Measurement of Vertical Profiles of the Atmospheric Surface Layer With Low-Cost Instrumentation on Board a Drone
Atmospheric natural disasters can have their damage mitigated if meteorological alerts are disseminated on time Among the ways to get data related to weather conditions are the use of atmospheric profilers and numerical models Such resources can be used for studies related to the surface layer which covers a range from 20 to 200 meters below the low troposphere In order to make atmospheric experiments achievable without great financial expenditure a low-cost atmospheric profiler was developed together with the Laboratory of Monitoring and Numerical Modeling of Climate Systems LAMMOC of the Federal Fluminense University UFF to be on board a drone and based on prototyping with Arduino which had as sensors the DHT22 for measuring temperature and relative humidity and the BMP280 for measuring atmospheric pressure Thus this profiler was used in an experiment from which atmospheric vertical profiles were generated and compared with profiles generated by the numerical model Weather Research and Forecasting WRF and post-processed by the WRF-Python routines package As a result it was noticed that the observed data profiles described a behavior of the surface layer that indicates the occurrence of thermal inversion and change of regime of this layer from the stable passing through the neutral to the unstable With this it is evaluated that the method of using this profiler can be applied in several atmospheric studies such as atmospheric pollution and nowcasting weather forecast as well as its potential for use in areas such as operational meteorology and assimilation of data from numerical models shows to be promisin
Does endodontic re-treatment in primary teeth increase the functional tooth retention? : A clinical, retrospective, university-based study
Objective: To investigate the longevity of endodontic treatments and the survival of endodontic re-treatments performed in primary teeth. Material and Methods: The sample included endodontic treatments and re-treatments conducted in anterior and posterior primary teeth without sedation or general anesthesia among children attending a university dental service. Information collected retrospectively from clinical records was used for analyzing data. The Kaplan-Meier estimator test was used to analyze the longevity and survival of endodontic treatment and re-treatments, respectively. Results: A total of 73 patients with endodontic therapy in primary teeth were included in the study, and 116 teeth were analyzed. After one year, the longevity of endodontic treatments performed on primary teeth was 65.74% with an annual failure rate (AFR) of 34.2%. From 47 endodontic treatment failures, 14 teeth (29.8%) were endodontically re-treated. When the endodontic re-treatment was considered as survival, the longevity of treatments reached 68.06% with 31.9% of AFR after one year of follow-up. There was a significant increase in functional tooth retention in those patients that received an endodontic re-treatment (p<0.001). Retreatment provided an additional mean survival time of 8.3 months. Conclusion: Endodontic treatments performed in primary teeth presented a limited longevity. Endodontic re-treatment is a more conservative alternative for endodontically treated primary teeth that have failed and significantly increase tooth retention
The impact of physical exercise on the skeletal muscle clock genes
The most important circadian synchronizer is the central clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The rhythmicity of all organs is achieved by molecular clock gene expression in the central clock and the pace is reached through neuronal and humoral signals to peripheral tissues. Skeletal muscle is one of the peripheral organs that express clock and clock controlled genes (CCGs) which display circadian rhythmicity. Recent studies have pointed out the role of clock genes in skeletal muscle function and
metabolism. The expression of clock genes in skeletal muscle might be altered by several external stimuli and also by different diseases. Physical exercise is a nonphotic stimulus that can realign the skeletal muscle circadian system to the central clock, imposing a new rhythm at the organism level. This effect may be crucial to prevent or ameliorate diseases and disorders caused by disruptions of circadian rhythms. In this review, we discuss the role of clock genes in skeletal muscle function and the importance of physical exercise as a potent synchronizing stimulus for the skeletal muscle molecular clock
SENSORIAMENTO REMOTO APLICADO AO MAPEAMENTO DA DINÂMICA DO USO DO SOLO NA BACIA DO RIO PACUÍ, NO NORTE DE MINAS GERAIS, NOS ANOS DE 1989, 1999 E 2009
The North of Minas Gerais has a concentration of climate with summer rains, so there is a shortage of rainfall in most years. Thus, the supply of surface water is compromised, which makes the subject of a water resource conflict and public interest. The Pacuí River Basin is a typical case of environmental conflict installed because the land use makes the supply of water is uneven across the basin. In this context, this study was to examine over the past two decades, through satellite images, the dynamics of land use Pacuí River Basin. This river is a tributary on the right bank of the São Francisco river and reaches nine counties north-miners. With the methodological procedure based on remote monitoring and field work was possible to identify the significant reduction of natural vegetation and a considerable increase in pasture area during the period analyzed.A mesorregião do Norte de Minas Gerais apresenta um clima com concentração das chuvas no verão, logo há escassez pluviométrica na maior parte do ano. Com isto, a oferta de água superficial é comprometida, o que torna o recurso hídrico um tema de conflito e de interesse público. A bacia do rio Pacuí é um caso típico de conflito ambiental instalado, pois o uso do solo faz com que a oferta da água seja desigual ao longo da bacia. Neste contexto, este trabalho buscou analisar ao longo das últimas duas décadas, através de imagens de satélite, a dinâmica no uso do solo da bacia do rio Pacuí. Este rio é afluente da margem direita do Rio São Francisco e atinge nove municípios norte-mineiros. Com o procedimento metodológico baseado em monitoramento remoto e trabalho de campo foi possível identificar a redução significativa da vegetação natural e o aumento considerável na área de pastagem, no decorrer do período analisado
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