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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.

Over the past 70 years, the understanding of Autism Spectrum Disorder (ASD) improved greatly and is characterized as a heterogeneous neuropsychiatric syndrome. ASD is characterized by difficulties in social communication, restricted and repetitive behavior, interests, or activities. And it is often described as a combination of genetic predisposition and environmental factors. There are many treatments and approaches to ASD, including pharmacological therapies with antipsychotics, antidepressants, mood regulators, stimulants, and behavioral ones. However, no treatment is capable of reverting ASD. This review provides an overview of animal models of autism. We summarized genetic and environmental models and then valproic acid treatment as a useful model for ASD. As well as the main therapies and approaches used in the treatment, relating them to the neurochemical pathways altered in ASD, emphasizing the pharmacological potential of peptides and bioinspired compounds found in animal venoms as a possible future treatment for ASD.

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

Alzheimer’s disease (AD) is the main cause of dementia in the world and its etiology is not yet fully understood. The pathology of AD is primarily characterized by intracellular neurofibrillary tangles and extracellular amyloid-β plaques. Unfortunately, few treatment options are available, and most treat symptoms, as is the case of acetylcholinesterase inhibitors (IAChE) and N-methyl-d-aspartate receptor antagonists. For more than 20 years pharmaceutical research has targeted the “amyloid cascade hypothesis,” but this has not produced meaningful results, leading researchers to focus now on other characteristics of the disease and on multitarget approaches. This review aims to evaluate some new treatments that are being developed and studied. Among these are new treatments based on peptides, which have high selectivity and low toxicity; however, these compounds have a short half-life and encounter challenges when crossing the blood-brain barrier. The present review discusses up-and-coming peptides tested as treatments and explores some nanotechnological strategies to overcome the downsides. These compounds are promising, as they not only act on the symptoms but also aim to prevent progressive neuronal loss.

Field and drill core hyperspectral sensing technologies are cost-effective tools for identifying footprints of hydrothermal mineral systems, vectoring towards potential ore bodies and differentiating domains in ore deposits. Hyperspectral visible-near, shortwave and thermal infrared data were collected from drill core and chip samples from the Cu-Zn-Mo deposit of Antamina, Peru, to map the relative abundance and chemical composition of major gangue minerals, such as garnet and quartz. This study focuses on grandite-series garnets (i.e. grossular to andradite), which show distinct variations with regard to their relative abundance and chemical composition across the Antamina deposit. Reflectance spectra were calibrated with quantitative mineralogy derived from scanning electron microscopy and X-ray diffraction-derived mineralogy. This allowed the modal abundances of garnet and quartz to be modelled using a partial least squares approach, achieving regression coefficients of up to 0.887 and 0.891, respectively. The accuracy of the modelled modal mineral abundance depended on the method of external calibration, and the mineral assemblage associated with the mineral of interest. Comparing the hyperspectral data with major sulfide mineralogy, whole-rock geochemistry, electron probe microanalysis and Fourier-transform infrared microscopy allowed the identification of five ore clusters at Antamina, including high Cu ± Zn-Mo; Zn + Cu ± Mo and Zn ± Cu in the exoskarn and Mo ± Cu-Zn and high Mo ± Cu-Zn in the endoskarn. The garnet species comprise mainly grossular ± andradite in the endoskarn and andradite in the exoskarn. Different garnet compositions are associated with different sulfide mineral assemblages, making Antamina an ideal candidate for evaluating hyperspectral sensing for rapid and reliable mineral characterisation of skarn deposits. Vector minerals typical of skarn deposits (e.g. garnet, vesuvianite) were determined using this approach, indicating its potential for effectively characterising skarn deposits worldwide.

Copper losses into slag within the flash furnace settler is an economically important topic for the primary copper production. Since the settler is not easily accessible to experimental studies due to harsh reaction conditions, numerical simulations are a promising alternative to obtain more insights into the settling behavior of matte. This study aims to increase the process understanding by developing a CFD flash furnace settler model of an industrial flash furnace. Thereby, the CFD model accounts for bath level changes, polydispersity, and coalescence of matte. Coalescence is modeled by an own empirical model focusing on gravitational coalescence. Matte settling shows size-dependent sedimentation within the slag layer, as supported by an own sampling study. Lowering the slag viscosity by a third decreases the copper loss by approximately 37 pct, while slightly increasing it leads to comparable results. Finally, average copper losses of 0.98 wt pct are estimated, finding good agreement with industrial data.

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.

Grinding media is very important in the mineral processing, mainly because its consumption involves significant costs of grinding and consequently, of the total mining operational expenditure. During grinding, chemical and physical consumptions take place. In both cases, operational variables play an important role but also mineralogy, because many pulp properties depend on it. In the present work, an experimental methodology to study grinding media consumption is proposed, following a geometallurgical approach. The methodology was applied on three Chilean copper sulfide ores to show the kind of results that can be achieved. In the laboratory case study presented, an empirical and predictive model of grinding media consumption as a function of grindability, operational variables (pulp pH and grinding time) and mineralogy, was obtained with the aid of advanced mineral characterisation techniques such as reflectance spectroscopy, X-ray diffraction and portable X-ray fluorescence. The results show that pH has an important effect on grinding media consumption, which may be due to the opposite relation between corrosion and an alkaline environment. Grindability also affects the grinding media consumption, but is related to a physical mechanism. It was found that the overall mineralogical composition and grindability of the ore may change the rate of grinding media consumption, which is greater for hard samples with highly reactive sulfide minerals. However, the highest consumption was obtained in samples with more sulfide minerals.

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.

In Latin America many mine sites are located more than 2000 m above sea level, and some over 4000 m above sea level. Portable X-ray ray fluorescence (pXRF) is becoming a routine method for collecting chemical data at different altitudes during mineral exploration campaigns. As altitude increases, air density decreases, and the physics of X-rays being transmitted through air mean that the transmission of low-energy X-rays increases and accordingly the transmission effectiveness of low-atomic weight elements (e.g. Mg, Al, and Si) also increases. Here we assess the performance of pXRF units across a range of pressures that equate to 0–5000 m above sea level by conducting well-documented tests with changing pressure to assess the use of a pXRF unit in high-altitude environments. Utilising both field test work, and test work using a hypobaric chamber in a laboratory where external conditions could be better controlled we examine how changing altitude can affect the performance of pXRF units. Units that have in-built pressure corrections perform reasonably consistently as altitude increases, whereas those that do not perform exactly as X-ray transmission modelling suggests. That is to say, the increased count rates of low-atomic weight elements (e.g. Mg, Al, and Si) means that these elements are over-reported and as a result the unit may under-report heavy elements.

The presence of clays in mineral processing offers a number of challenges that range from valuable species recovery to the transport of tailings. In particular, when the abundance of one or more clay types increases, the rheology may be significantly affected. In this paper, the feasibility of using hyperspectral characterization to estimate rheological properties of mineral suspensions was studied. Towards this purpose, a set of rheology measurements was made for slurries of different composition, combining up to three out of five minerals: three clay minerals (two bentonites from different sources and kaolin), quartz and white mica, which are the main gangue minerals present in the Chilean copper mining industry. Using a Bingham Plastic flow model, a set of ternary plots for Bingham viscosity and yield stress was obtained. Results show counter-intuitive behavior for kaolin-white mica mixtures, showing a minimum for viscosity at a 2:3 ratio respectively. In addition, mechanisms for lowering the high viscosity reached by bentonite slurries were assessed. Modelling of the hyperspectral data produced high accuracy estimates of the mineral abundances, enabling an accurate determination of the respective samples position in the ternary mineralogy-rheology diagrams.

The present paper presents a part of the research efforts of the laboratory of Metallurgy, National Technical University of Athens, Greece, aiming at developing a purely hydrometallurgical method, able to treat the zincferous dust, generated during the production of steel from scraps in Electric Arc Furnace (EAF), efficiently and economically and especially so for annual capacities lower than 50,000 tonnes of dust, for which the currently applied industrial methods are not economical. The proposed method is based on direct sulphuric acid leaching of the EAF dust and it succeeds to recover the valuable metals contained in it, such as zinc, lead and cadmium, converting the initially hazardous waste into a residue suitable to be fed to cement industry. The EAF dust sample, provided by a Greek steel plant, was initially leached with water, at certain conditions, to remove as much of the contained calcium as possible without co-dissolution of other metals. The washed dust was further subjected to three–stage leaching at atmospheric pressure, using sulphuric acid concentrations of 2N and 3N and temperatures 25 °C, at the first stage, and 95 °C, at the second and third stages. Total percent extraction values achieved were 97 % for zinc and 97 % for cadmium. Almost all lead, 99.7 %, remained undissolved as lead sulphate in the leach residues. It was shown experimentally that lead can be recovered as saleable lead sulphide while zinc can be recovered from the pregnant solution by solvent extraction with D2EHPA. Finally, based on the results, a conceptual flowsheet of the proposed integrated hydrometallurgical method for the treatment of EAF dust was established and is given.

The aim of the current research study was the development of a hydrometallurgical process for the recovery of metals from electric arc furnace dust. The behaviors of zinc, cadmium, iron, and lead in sulfuric acid were investigated. The recovery of the zinc (from zinc oxide) and cadmium is possible with a relatively high yield, as iron and lead remain in the solid residue after two stages of leaching at room temperature. In a third stage, zinc recovery from the zinc ferrite (in the leached residue) was carried out by pressure leaching. Under the optimum conditions of treatment and after three stages of processing, the total extractions of zinc and cadmium were 99 and 94 pct, respectively. Lead and the main part of iron remain in the residue. The proposed process also resulted in the reduction of the initial residue mass by 30 pct.

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.