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This paper aims to study the influence of the binder saturation level on the accuracy and on the mechanical properties of three-dimensional (3D)-printed scaffolds for bone tissue engineering.

To study the influence of the liquid binder volume on the models accuracy, two quality test plates with different macropore sizes were designed and produced. For the mechanical and physical characterisation, cylindrical specimens were used. The models were printed using a calcium phosphate powder, which was characterised in terms of composition, particle size and morphology, by X-ray diffraction (XRD), laser diffraction and Scanning electron microscopy (SEM) analysis. The sample’s physical characterisation was made using the Archimedes method (porosity), SEM, micro-computer tomography (CT) and digital scan techniques, while the mechanical characterisation was performed by means of uniaxial compressive tests. Strength distribution was analysed using a statistical Weibull approach, and the dependence of the compressive strength on the porosity was discussed.

The saturation level is determinant for the structural characteristics, accuracy and strength the models produced by three-dimensional printing (3DP). Samples printed with the highest saturation showed higher compressive strengths (24 MPa), which are over the human trabecular bone. The models printed with lower saturations presented the highest accuracy and pore interconnectivity.

This study allowed to acquire important knowledge concerning the effects of shell/core saturation on the overall performance of the 3DP. With this information it is possible to devise scaffolds with the required properties for bone scaffold engineering.

The purpose of this paper is to ask why poor performance management practices persist in Portugal, in the middle of claims to increase productivity.

An inductive micro-practice analysis is used to understand barriers to management practice that do not require massive institutional changes.

The practice of performance management in Portugal typically displays three weaknesses: (1) insufficient planning (2) process and integrity issues, and (3) a non-meritocratic logic.

The paper discusses the important topic of persistence of bad practices, showing how institutionalized patterns might be difficult to eradicate even they are suboptimal.

The authors identity key issues in the functioning of performance management, therefore helping managers in developing remedies to improve the quality of their practice.

The paper explains the persistence of bad management practice whose continuity hinders not only organizations’ effectiveness but also that of their members.

The environmental consciousness of customers and the emergence of stricter environmental regulations has pushed industries to think about environmental management by means of reverse logistics (RL) implementation. The purpose of this paper is to provide a current panorama of RL in Brazil and a comparison to international RL body of literature as well. It also seeks to provide a systematic literature review procedure and a conceptual framework for RL literature categorization.

A descriptive and content analysis approach was adopted. First, a topic delimitation phase was aimed at defining the main research areas and related keywords. Second, a material collection phase focussed on a selection of peer-reviewed Brazilian and international journals. Third, a total of 34 papers were assessed by quantitative indicators, and a conceptual RL framework was employed to classify them. Finally, papers were evaluated using content analysis.

The RL research gaps in Brazil are in information technology, facility location, inventory control, outsourcing, and performance measurement. It is also reported that, In Brazil, RL is predominantly linked to recycling activities, and the practice of RL is driven by social conditions and economics in some specific industrial sectors.

The focus is restricted to RL applications in Brazil and the corresponding articles published by Brazilian researchers.

Practitioners and academics might find this review useful, as it outlines gaps and limitations of existing research in the largest Latin America economy. This work is built on the recent research in RL. No systematic literature review of this kind has previously been undertaken.

This paper examines the impact of extreme rainfall shocks on the performance in test scores of students living near at-risk urban areas in Brazil.

To identify the causal effect, we consider the exogenous variation of rainfall at the municipal level conditioned on the distance from the school to risk areas and the rainfall intensity in the school months.

The results suggest that extreme precipitation shocks, defined as a shock of at least three months of high-intensity rainfall, have an adverse impact on both math and language performance. Through a heterogeneous effects analysis, we find that the impact varies by student gender, with girls being more affected. In addition, among students who study near at-risk areas, those with better previous school performance and higher socioeconomic status are more negatively affected.

Our results suggest that extreme weather events can increase the differences in human capital accumulation between the population living near risk areas and those living more distant from these areas.

The purpose of this study is to evaluate the yield, physico-chemical and microbiological parameters during the shelf life of the Minas Frescal cheese hand-manufactured by family farms.

In the milk, analyses of total bacterial counts, somatic cell counts and centesimal composition were performed. The milk coagulation was analyzed, with different curd times (40, 80 and 120 min), with respect to the proximate composition, pH, titratable acidity, yield and microbiological counts. The means were compared using the Tukey test with a significance level of 5 per cent. The most probable number of microorganisms were also determined in water.

The results for milk quality were within the requirements established in Normative Instruction 62, except for total dry extract. It was found that curd time did not influence the protein and fat in dry matter contents; however, the ash content in cheese of 40 min of curd time (2.8 g/100g) is significantly higher (p = 0.02) than the values found for the other curd times. The same behavior was observed for moisture content (p = 0.04). The parameters determining the cheese quality were outside the standards for human consumption, but this result is directly related to the water conditions, which were outside of potability levels. To meet the requirements established in the legislation, dairy products must follow strict standards of quality hygiene, both the raw material (water, milk) and their employees who act directly in the process.

For the preparation of the Minas Frescal cheese, it takes several steps, from obtaining the milk to the product ready to be consumed, so the importance of doing this monitoring and evaluating its quality.