AbstractThe behaviour of standard boltedsteel connections submitted to monotonic loads, through the use of numerical models, is presented in the current paper.The bolted connections allow speed up constructive processes in an increasingly competitive and globalized world in which the costs are a decisive factor in the development of a project. The use of computational tools in the analysis of bolted connections becomes determinant, mainly for new solutions or solutions less explored in terms of design codes.Throughout the years, bolted connections have been suffering transformations resulting from research activities performed by many authors. Rivets have been replaced by bolts, the main achievement being the pre-stressed bolts. Methodologies based on finite element analyses were proposed for double shear bolted connection. The non-linear behaviour of these connections is investigated and their performances are compared. In the numerical modelling of the bolted connection, linear elastic and elastoplastic analyzes reveal that there are two slip levels associated with local non-linearities caused by the contact pairs, which vary with clamping stresses.

The teacher's knowledge of the mathematical fidelity of technology and the impact it has on the teacher’s practice is the focus of this article. Based on the conceptualization of Knowledge for Teaching Mathematics with Technology (KTMT), and involving the teaching of Functions at the 10th grade, we analyze: the situations of lack of mathematical fidelity considered by the teacher in the classes, the way how the teacher manages students' contact with this kind of situations, and how the teacher supports students when they are faced with a lack of mathematical fidelity. The conclusions reached point to: some devaluation of the situations of lack of mathematical fidelity, with only one type of situation being explicitly addressed; a careful selection of tasks, in order to ensure that these situations do not occur too soon; a focus on the identification by the students of this type of situation, suggesting what they can do to confirm the suspicion but without effective implementation of the process. As a consequence, knowledge of mathematical fidelity does not necessarily have a relevant impact on teacher’s practice and it is not easily transformed into a deep teacher’s KTMT.

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The development of meaningful learning becomes possible when students are actively involved in solving real problems. Thus, this study intends to investigate how students of the 11th grade of a vocational course solve problems of Linear Programming, using the graphing calculator. The conclusions reached indicate that: the interpretation of the conditions of the problems is the most delicate point; the graphical approach using technology is dominant; and the difficulties raised by the problem as well as the need to discuss the results achieved are the basis for the interactions both among the students and between them and the teacher.

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Abstract The current chromatographic approaches used in protein purification are not keeping pace with the increasing biopharmaceutical market demand. With the upstream improvements, the bottleneck shifted towards the downstream process. New approaches rely in Anything But Chromatography methodologies and revisiting former techniques with a bioprocess perspective. Protein crystallization and precipitation methods are already implemented in the downstream process of diverse therapeutic biological macromolecules, overcoming the current chromatographic bottlenecks. Promising work is being developed in order to implement crystallization and precipitation in the purification pipeline of high value therapeutic molecules. This review focuses in the role of these two methodologies in current industrial purification processes, and highlights their potential implementation in the purification pipeline of high value therapeutic molecules, overcoming chromatographic holdups.

The assessment and the role it should be assumed by the summative and formative component are often a reason for discussion. It is therefore important to understand how the teacher assessment practices are characterized and what influences them. That is, identify aspects taken into account when planning assessment; the (dis)continuities between assessment and learning; the divergences/consonances between assessment planned and implemented. The conclusions reached point to a strong influence of peers, to the assessment criteria of the school and to the students’ characteristics, in a scenario where the test is the dominant element in assessment.

Abstract Strengthening of concrete structures with a new concrete layer has been commonly used for columns, beams and slabs. This technique is economic and efficient for structural strengthening since it uses the same base materials, steel and concrete. It is usually applied on the compressed face of the concrete element due to concrete’s recognized behaviour under compression, posing several challenges to control cracking and resistance when applied on the tensile face. For assessing the performance of the strengthening method, twelve slab specimens were designed and tested monotonically. The main parameters to assess in this work were the debonding behaviour and load, and the relationship between the latter and the relative displacements at the interface of the two concrete layers. The performance of the strengthened structures strongly relies on the interaction of the two concrete layers, with this being the main subject of the research about overlaid concrete. The load transfer capacity of the interface depends on the interface shear strength, which in turn is highly dependable on substrate roughness, cleanliness and curing conditions of the newly added layer. Interface performance may be improved by using steel connectors crossing the interface, properly anchored on both layers. The importance for these elements grows as the existing concrete is more deteriorated, since adhesion strength will decrease with lower quality concrete. This paper presents the experimental research for the application of bonded concrete overlays on the tensile face of reinforced concrete slabs, mainly aimed at office buildings and parking facilities, where spatial clearances or inaccessibility to the lower side of the slabs are recurrent. A ductile behaviour upon debonding was achieved for the specimens with reinforcement crossing the interface, and a debonding load up to three times that of the reference specimens without reinforcement crossing the interface.

Teaching statistics is often based on an approach focused on teaching theoretical aspects, disconnected from
practical relevance and from interpretation of results, and where the use of technology lies behind its potential. In
this context, it is important to analyze how the teachers’ knowledge is characterized and to identify aspects of this
knowledge that mark the professional practice. The conclusions reached emphasize the impact of content
knowledge and its influence on knowledge of content and teaching. Knowledge of curriculum is also relevant, as
well as the way how it seems to prevent the development of other types of knowledge.

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