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The formation of accretion layers within the waste heat boiler is a serious operational concern as it can potentially increase boiler downtime and, hence, limit continuous production. In previous Computational Fluid Dynamics studies, the accretion formation was predicted for an industrial-scale waste heat boiler, using a dust stickiness sub-routine of the model. In this study, a dust sampling campaign was used to validate this stickiness sub-routine. Furthermore, various sticking and reaction mechanisms of flue dust were investigated and compared to thermodynamic predictions. While the results suggest that the sub-routine is valid, the comparison of thermodynamics and species in the samples showed that the chemical reactions of the flue dust did not reach the thermodynamic equilibrium. Graphical Abstract

The Flash Smelting Furnace (FSF) is one of the most common reactors for the primary smelting of copper concentrates. Its smooth operation depends on the availability and performance of the downstream Waste Heat Boiler (WHB). The WHB is especially sensitive to problems with its flue dust handling, such as the formation of accretions, which can lead to downtime and equipment failures. Due to the limited accessibility and the harsh conditions of the WHB, experimental studies are challenging. Therefore, CFD simulations can be a promising option to increase knowledge and evaluate a range of options. The present study investigates the physical behavior of flue dust in an industrial-scale WHB via a three-dimensional CFD model. Size-dependent particle sedimentation and the risk areas for flue dust accretions are predicted, finding good agreement with industrial experience and data from the literature. To make the evaluation of accretion risk zones possible, a new sticking function for flue dust is developed. The results are validated against dust samples. Finally, operational recommendations for minimizing flue dust accretions are derived.

Hox genes represent an important gene family that is involved in the segmentation pattern and identity of the segments during the formation of the body plan in metazoans. For many years, several studies have sought to establish a correlation between the evolution of these genes and the evolution of large groups of metazoans. Here, we use publicly available sequences of Hox gene clusters to reconstruct the evolutionary history of anterior Hox genes. We show that information harbored by these genes, in part, reflects the evolution and diversification of most animal archetypes, but in many cases, there were conflicts between the evolutionary history of some genes and the history of large groups, these cases may have occurred due to specific and similar selective pressures in relatively distant groups, which may have led to evolutionary convergences. Our findings also reveal that the evolution of Hox genes (and clusters) as a multigene family is consistent to a birth-and-death model constrained by development, where there is a trade-off between a relatively fast gene turnover and their central developmental roles

Compared to honeybees and bumblebees, the effect of diet on the gut microbiome of Neotropical corbiculate bees such as Melipona spp. is largely unknown. These bees have been managed for centuries, but recently an annual disease is affecting M. quadrifasciata, an endangered species kept exclusively by management in Southern Brazil. Here we report the results of a longitudinal metabarcoding study involving the period of M. quadrifasciata colony weakness, designed to monitor the gut microbiota and diet changes preceding an outbreak. We found increasing amounts of bacteria associated to the gut of forager bees two months before the first symptoms have been recorded. Simultaneously, forager bees showed decreasing body weight. The accelerated growth of gut-associated bacteria was uneven among taxa, with Bifidobacteriaceae dominating, and Lactobacillaceae decreasing in relative abundance within the bacterial community. Dominant fungi such as Candida and Starmerella also decreased in numbers, and the stingless bee obligate symbiont Zygosaccharomyces showed the lowest relative abundance during the outbreak period. Such changes were associated with pronounced diet shifts, i.e., the rise of Eucalyptus spp. pollen amount in forager bees’ guts. Furthermore, there was a negative correlation between the amount of Eucalyptus pollen in diets and the abundance of some bacterial taxa in the gut associated microbiota. We conclude that diet and subsequent interactions with the gut microbiome are key environmental components of the annual disease, and propose the use of diet supplementation as means to sustain the activity of stingless bee keeping as well as native bee pollination services.

Entanglement had played a crucial role in developing frontier technologies as a critical resource, for instance, in quantum teleportation and quantum sensing schemes. Notably, thanks to the ability to cool down the vibrational modes of mechanical oscillators to its quantum regime, entanglement between mechanical modes and the production of nonclassical mechanical states have emerged as central resources for quantum technological applications. Thus, proposing deterministic schemes to achieve those tasks is of paramount importance. While the dominant scheme for bipartite mechanical entanglement involves Gaussian optomechanical interactions (linearized regime) to generate two-mode squeezed vacuum states, entangling two-modes exploiting the bare non-Gaussian optomechanical interaction (nonlinear strong single-photon regime) remains less covered. This work proposes an on-demand scheme to engineer phononic non-Gaussian bipartite entanglement in the nonlinear regime by exploiting cavity dissipation. Interestingly, our protocol (operating in the resolved sideband and photon blockade regime) renders the possibility of achieving a high degree of steady-state entanglement. We further show that our deterministic scheme is robust in the presence of decoherence and temperature within state-of-the-art optomechanics, along with the required conditions to obtain non-Gaussianity of the achieved bipartite mechanical steady-state.

A partir das disciplinas Educação e Tecnologia e Narrativa Ficcional e Documentário do Curso de Rádio e Televisão da UFMA, foi elaborado um produto audiovisual que relaciona arte urbana, comunicação e educação. O “documentário grafite.mp4” apresenta o processo de ensino baseado nas experiências de vida advindas dos educadores e educandos através do ato comunicativo, onde a arte urbana funciona como meio de repensar esses processos dentro do espaço escolar. Logo, este presente trabalho busca analisar teoricamente tais atos evidenciados na produção do documentário, traçando caminhos conceituais para compreendê-los, através do tripé teórico comunicação,experiência e educação.Grafitti.mp4 documentary: refletions on the education communication interfaceAbstractFrom the subjects Education and Technology and Fictional Narrative and Documentary of the Radio and Television Course at UFMA, an audiovisual product was made to relate urban art, communication and education. The “grafite.mp4 documentary” presents the teaching process based on life experiences arising from educators and students through the communicative act, where urban art works as ways of rethinking these processes within the school space. Therefore, this present work seeks to theoretically analise such acts evidenced in the production of the documentary, tracing conceptual paths to understand them, through the theoretical tripod communication, education and experience.Keywords: Communication; education; experience; documentary.

Most of the dust generated from the copper smelting process in Chili has been stored after the stabilization by hydrometallurgical process because it contains high concentration of arsenic. However, in recent years, the generation of dust has increased because of degrading the quality of concentrate. In addition, the environmental regulations become stricter. On the other hand, valuable metals such as copper and zinc are contained in the dust at high concentrations and it is desirable to recover them. In this study, the effect of recirculation of dust to the smelting process was examined in order not only to decrease the amount of dust but also to recover copper. The generation of dust and the distribution of arsenic, lead, zinc and so on among the matte, slag and gas phases were evaluated as a function of the amount of recirculated dust, partial pressure of oxygen and temperature. It was found that the direct return of dust to the smelting process was quite effective for the recovery of copper and the reduction of dust amount, but the acceptable amount of returnable dust was limited by the produced matte quality.

Resumo Objetivos: analisar os fatores de risco para a não amamentação em Pernambuco, Nordeste do Brasil, em 2006. Métodos: estudo caso-controle, cujos casos (70 crianças que nunca mamaram) e controles (140 crianças amamentadas exclusivamente por quatro meses ou mais) foram pareados por sexo e idade, tendo como base dados da III Pesquisa Estadual de Saúde e Nutrição realizada em Pernambuco, em 2006. Foram analisados fatores maternos e biológicos das crianças. Calcularam-se, através de análises bivariadas, as razões de chance brutas (odds ratio). Mediante ajustamentos aplicados por regressão logística de Poisson, foram seletivamente incorporadas as variáveis com valor p

Objetivou-se descrever e analisar a prática do aleitamento materno em crianças menores de cinco anos no estado de Pernambuco, em 2006, segundo o peso ao nascer. Estudo transversal, com amostra de 1.595 crianças. Utilizou-se o teste chi-quadrado de Pearson para analisar associações bivariadas e a regressão de Poisson para o ajustamento de modelo multivariado dos fatores condicionantes ao aleitamento exclusivo > 4 meses, segundo o peso ao nascer. Verificou-se que a realização do pré-natal e o número de consultas beneficiaram as crianças que nasceram com peso > 2.500g, quando comparadas aos casos com peso < 2.500g (baixo peso ao nascer - BPN). Não houve diferença estatística nas classificações do aleitamento materno, segundo o peso ao nascer. As variáveis anos de estudo formal e tipo de parto apresentaram-se associadas ao grupo de BPN, enquanto que para as crianças com peso > 2.500g foram detectadas associações com as variáveis renda per capita, espaço geográfico, orientação sobre aleitamento materno no pré-natal e sexo das crianças. O grupo de crianças BPN não foi favorecido quanto às recomendações referentes ao aleitamento materno, bem como foram diferentes os resultados das relações das variáveis que permaneceram nos dois grupos representando os modelos finais de análises multivariadas. The scope of this paper was to describe and analyze the practice of breastfeeding in children under five years of age in the state of Pernambuco, in 2006 in accordance with birth weight. It involved a cross-sectional study with a sample of 1,595 children. The chi square test was used to examine bivariate associations and Poisson regression was applied for multivariate adjustment of conditioning factors to exclusive breastfeeding > 4 months, according to birth weight. It was found that the practice of prenatal care and number of visits benefited children born weighing > 2,500 gram, compared to those with birth weight < 2,500 g (low birth weight - LBW). There was no statistical difference in the ratings of breastfeeding, according to birth weight. The years of formal study and type of delivery variables were linked to the group associated with LBW, while for children weighing > 2,500 g associations with the per capita income, geographical area, guidance on breastfeeding during prenatal care and sex of the children variables were detected. The group of LBW children did not benefit from recommendations regarding breastfeeding and also the results from the relations of the variables that remained in the two groups were different, representing the final models of the multivariate analyses.

The scope of this paper was to describe and analyze the practice of breastfeeding in children under five years of age in the state of Pernambuco, in 2006 in accordance with birth weight. It involved a cross-sectional study with a sample of 1,595 children. The chi square test was used to examine bivariate associations and Poisson regression was applied for multivariate adjustment of conditioning factors to exclusive breastfeeding4 months, according to birth weight. It was found that the practice of prenatal care and number of visits benefited children born weighing2,500 gram, compared to those with birth weight2,500 g (low birth weight - LBW). There was no statistical difference in the ratings of breastfeeding, according to birth weight. The years of formal study and type of delivery variables were linked to the group associated with LBW, while for children weighing2,500 g associations with the per capita income, geographical area, guidance on breastfeeding during prenatal care and sex of the children variables were detected. The group of LBW children did not benefit from recommendations regarding breastfeeding and also the results from the relations of the variables that remained in the two groups were different, representing the final models of the multivariate analyses.