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In this work, iron-bearing mining reject was employed as an alternative and potential low-cost catalyst to degrade phenol in water by photo-Fenton strategy. Various techniques, including SEM-EDS, BET, FTIR, and XRD, were applied to evaluate the material's properties. Process parameters such as hydrogen peroxide concentration, catalyst dosage, and pH were studied to determine the optimum reaction conditions ([catalyst] = 0.75 g L-1, [H2O2] = 7.5 mM, and pH = 3). Phenol degradation and mineralization efficiencies at 180 and 300 min were 96.5 and 78%, respectively. These satisfactory results can be associated with the iron amount present in the waste sample. Furthermore, the material showed high catalytic activity and negligible iron leaching even after the fourth reuse cycle. The degradation behavior of phenol in water was well represented by a kinetic model based on the Fermi function. The iron-bearing mining reject can be considered a potential photo-Fenton catalyst for phenol degradation in wastewater.

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The development of Brain-Computer Interfaces based on Motor Imagery (MI) tasks is a relevant research topic worldwide. The design of accurate and reliable BCI systems remains a challenge, mainly in terms of increasing performance and usability. Classifiers based on Bayesian Neural Networks are proposed in this work by using the variational inference, aiming to analyze the uncertainty during the MI prediction. An adaptive threshold scheme is proposed here for MI classification with a reject option, and its performance on both datasets 2a and 2b from BCI Competition IV is compared with other approaches based on thresholds. The results using subject-specific and non-subject-specific training strategies are encouraging. From the uncertainty analysis, considerations for reducing computational cost are proposed for future work.

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This study's aim is to generate a complete profile of reverse osmosis concentrate (ROC), including physicochemical characteristics, environmental impact, and technologies for ROC treatment, alongside element recovery with potential valorization. A systematic literature review was used to compile and analyze scientific information about ROC, and systematic identification and evaluation of the data/evidence in the articles were conducted using the methodological principles of grounded data theory. The literature analysis revealed that two actions are imperative: (1) countries should impose strict regulations to avoid the contamination of receiving water bodies and (2) desalination plants should apply circular economies. Currently, synergizing conventional and emerging technologies is the most efficient method to mitigate the environmental impact of desalination processes. However, constructed wetlands are an emerging technology that promise to be a viable multi-benefit solution, as they can provide simultaneous treatment of nutrients, metals, and trace organic contaminants at a relatively low cost, and are socially accepted; therefore, they are a sustainable solution.

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In studies of simple and conditional discrimination, procedures are needed to measure those aspects of stimuli that control behavior. The blank comparison procedure is one such procedure. It was designed explicitly for assessing S+ and S- functions when discriminative stimuli are presented simultaneously. In this procedure, a neutral stimulus serves sometimes as S+ and sometimes as S-. Its discriminative function is defined in relation to other stimuli in the display. The present study aimed to prepare 2 infant female capuchin monkeys for the effective use of the blank comparison procedure in a simple discrimination task. First, simple discrimination training was applied up to a stable accuracy criterion of ≥90%. This training was followed by the replacement of S+ and then of S- stimuli with new stimuli. Ultimately, trials with the blank comparison were introduced. Following this sequence, both monkeys immediately displayed highly accurate blank-comparison performances without the need for stimulus control shaping or other preparatory discrimination training. Thus, this procedure sequence may be an efficient, effective method for establishing blank-comparison baselines for experimental analyses of S+/S- discriminative functions and perhaps for other applications in teaching simple and conditional discrimination performances to this species and others.

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The establishment of sample/S- relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching-to-sample with observing requirements (MTS-OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject-control patterns during tests slightly increased and the number of participants showing select-control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.

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Resumo O presente estudo avaliou o efeito dos controles por seleção e por rejeição sobre a observação de S+ e S- em treinos de emparelhamento com o modelo. Quatro adultos foram expostos a treinos de discriminação condicional e testes de equivalência. Na condição de Linha de Base (LB), nenhuma relação de controle modelo/comparação específica foi favorecida; nas condições de Controle por Rejeição e Controle por Seleção, as relações modelo/S- e modelo/S+ foram favorecidas, respectivamente. Na condição LB, foi verificada uma maior observação do S+ em comparação ao S-. O estabelecimento do controle por rejeição tendeu a ser acompanhado por uma maior observação do S- e por escolhas baseadas na observação exclusiva do S-; no caso do controle por seleção, padrões similares foram verificados, porém para o S+. Foi concluído que o estabelecimento dos controles por seleção e por rejeição são acompanhados de mudanças na observação dos estímulos de comparação.

Abstract The present study investigated the effects of select and reject controls upon S+ and S- observations during a matching-to-sample training. Four adults were exposed to discriminative trainings and equivalence tests. In Baseline (BL), no specific sample-comparison control was biased; in the Reject Control and Select Control conditions, sample/S+ and sample/S- relations were biased, respectively. In BL, participants observed more the S+ than the S-. The establishment of reject control tended to be followed by an increase in the observation of the S- and by choices based on the exclusive observation of the S-; in the case of select control, similar patterns were found, however, for the S+. Thus, the establishment of select and reject controls are followed by changes in the observation of comparison stimuli.

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Rejects from selective collection are municipal solid waste (MSW) not used for recycling and are, therefore, destined for the landfill in Brazil. Knowledge of the composition and generation of this waste is important for strategically planning public policies that minimize its generation and its negative environmental impacts. However, this portion of MSW is not very well known. Therefore, the aim of this study was to analyze the rejects from the sorting process of the selective waste collection in the municipality of Blumenau, in the State of Santa Catarina, southern Brazil. The studied rejects came from the largest cooperative in the city, and its composition was sorted into 17 categories of 101 samples over the course of one year, with a total of 3893 kg of analyzed rejects. The waste collected by the selective collection of the municipality was evaluated monthly to determine which part of this quantity became rejects and to determine the composition and seasonality of these rejects. The study found that 30.5% of the waste sorted by the cooperative was rejected. Among these rejects, the presence of materials that could be marketed by the cooperative was verified. Hazardous and/or legally prohibited waste were also identified, as were organics, construction and demolition waste, health care waste, electronics, textiles, footwear, batteries, and bulbs. Seasonal analysis indicated a concerning constant generation of health care waste. Aside from that, there was an increase in the generation of waste from electrical and electronic equipment (EEE) during the Christmas period, when a large part of the population discards their EEE. This information is important for the enforcement of the MSW management structure as well as for educational campaigns aimed at the correct separation of waste that should be sent for selective collection.

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In the final process of the bleached kraft pulp there are some cellulose fibers that are separated from the main fibers stream; these fibers are rejected and considered as a low quality fibers, these fibers are known as rejected fiber (RF). In the present work the potential use of these fibers for Cellulose Nanocrystals (CNCs) synthesis was studied. The physical and chemical properties of synthesized CNCs were characterized through different techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA). Results demonstrate the feasibility of CNCs synthesis with a yield of 28.1% and 36.9%, and crystallinity of 73.5% and 82.7%. Finally, the morphology and synthesis conditions suggest that this industrial reject fiber (RF) could be used as a source for the CNCs production, thus adding value to the kraft process and opening new possibilities for innovation in the pulp industry.

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The present study used a single-subject design to evaluate the effects of select or reject control on equivalence class formation and transfer of function. Adults were exposed to a matching-to-sample task with observing requirements (MTS-OR) in order to bias the establishment of sample/S+ (select) or sample/S- (reject) relations. In Experiment 1, four sets of baseline conditional relations were taught-two under reject control (A1B2C1, A2B1C2) and two under select control (D1E1F1, D2E2F2). Participants were tested for transitivity, symmetry, equivalence and reflexivity. They also learned a simple discrimination involving one of the stimuli from the equivalence classes and were tested for the transfer of the discriminative function. In general, participants performed with high accuracy on all equivalence-related probes as well as the transfer of function probes under select control. Under reject control, participants had high scores only on the symmetry test; transfer of function was attributed to stimuli programmed as S-. In Experiment 2, the equivalence class under reject control was expanded to four members (A1B2C1D2; A2B1C2D1). Participants had high scores only on symmetry and on transitivity and equivalence tests involving two nodes. Transfer of function was extended to the programmed S- added to each class. Results from both experiments suggest that select and reject controls might differently affect the formation of equivalence classes and the transfer of stimulus functions.

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Este estudio buscó identificar comportamientos y actitudes que asocian niños y niñas, entre los 9 y 11 años de edad, con la aceptación y el rechazo social en un grupo escolar. Se pidió a los niños y niñas hacer estimaciones sobre la importancia que distintas cualidades y defectos tienen como factores que contribuyen a que un niño sea aceptado, o por el contrario, sufra el rechazo de sus compañeros de colegio. Para la recolección de los datos, se utilizaron tres instrumentos: un test sociométrico, un cuestionario sobre cualidades que contribuyen a que el niño goce de aceptación social y un cuestionario sobre defectos que conducen al rechazo de los compañeros. Estos instrumentos se aplicaron colectivamente en el aula de clase con la instrucción de responder independientemente sin comentar sus respuestas con sus compañeros. Los datos obtenidos fueron procesados estadísticamente a través de análisis de correlación y de varianza. La mayoría de los niños coincidió en sus juicios sobre el grado de importancia de algunas cualidades y algunos defectos. Al comparar niños y niñas, se observaron diferencias significativas en sus apreciaciones sobre algunas cualidades. El grado de integración social ostentado por los niños en su grupo escolar no pareció incidir en forma significativa sobre los juicios que expresaron. Los resultados sugieren algunos perfiles prototípicos de niños aceptados y rechazados en los grupos escolares.

The aim of this study was to identify behaviors and attitudes that children, between the 9 and 11 years of age, associate with the acceptance and the social rejection within a school group. Children were asked to make estimations about the importance that different qualities and defects have as factors that contribute to that a boy could be accepted, or on the contrary, feel the rejection of its schoolmates. To collect the information, tree measuring instruments were used: a socio-metric test, a questionnaire on qualities that contribute a child to enjoy to be accepted and a questionnaire on defects that lead to the rejection of the partnerships. These instruments were applied collectively in the classroom, but it was asked each boy to respond independently without commenting its answers with its classmates. The collected data were process statistically through variance and correlation analysis. Most of the children's answer coincided on the degree of importance of some qualities and some defects. The degree of social integration shown social integration shown by the children within its scholar group did not seem to affect significant form the judgments that expressed. The results suggest some prototypes profiles of accepted and rejected children to the interior of the scholar groups.