Fused Filament Fabrication (FFF) has become a widely adopted additive manufacturing technology due to its cost-effectiveness, material versatility, and accessibility. However, optimizing process parameters, predicting material behavior, and ensuring structural reliability remain major challenges. This review analyzes state-of-the-art computational methods used in FFF, which are categorized into four main areas: melt flow dynamics, cooling and solidification, thermal–mechanical behavior, and material property characterization. Notably, the integration of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) has led to improved predictions of key phenomena, such as filament deformation, residual stresses, and temperature gradients. The growing use of fiber-reinforced filaments has further enhanced mechanical performance; however, this also introduces added complexity due to filler orientation effects and interlayer adhesion issues. A critical limitation across existing studies is the lack of standardized experimental validation methods, which hinders model comparability and reproducibility. This review highlights the need for unified testing protocols, more accurate multi-physics simulations, and the integration of AI-based process monitoring to bridge the gap between numerical predictions and real-world performance. Addressing these gaps will be essential to advancing FFF as a precise and scalable manufacturing platform.

Background: Health-related quality of life (HRQoL) allows knowing the subject’s feelings in distress and well-being, as well as perception of current and future health. Objective: To assess associations between health-related quality of life, fitness status, and adherence to the Mediterranean diet in Spanish children and adolescents. Methods: A cross-sectional study was carried out in a sample of 305 (47.2% women) children and adolescents aged between 8 and 16 years, in the primary and secondary schools of the province of Ávila (central Spain) (NCT05380674). Subjects were classified according to their quality of life: group 1 (highest quality of life) > group 2 (medium quality of life) > group 3 (lowest quality of life). Results: More participants in group 1 showed higher adherence to Mediterranean diet (70.8%) than other groups (group 2: 55.0%; group 3: 43.4%). It was less likely to find optimal levels of muscle strength as quality of life decreased (OR; 95% CI: group 2: 0.535; 0.303–0.955; and group 3: 0.424; 0.234–0.768). Similar trends were found for speed and agility, but only group 3 showed significant results (OR; 95% CI: group 3: 0.297; 0.162–0.545). Flexibility was also the worst in groups 2 and 3 (OR; 95% CI: G2: 0.403; 0.213–0.762; and group 3: 0.520; 0.282–0.958). Conclusion: High fitness status and adherence to the Mediterranean diet were associated with improved health-related quality of life in schoolchildren of central Spain.

This paper studies the drawing-induced intercolonial microdamage (ICMD) in pearlitic microstructures. The analysis was performed from the direct observation of the microstructure of the progressively cold-drawn pearlitic steel wires associated with the distinct steps (cold-drawing passes) of a real cold-drawing manufacturing scheme, constituted by seven cold-drawing passes. Three types of ICMD were found in the pearlitic steel microstructures, all affecting two or more pearlite colonies, namely: (i) intercolonial tearing; (ii) multi-colonial tearing; and (iii) micro-decolonization. The ICMD evolution is quite relevant to the subsequent fracture process of cold-drawn pearlitic steel wires, since the drawing-induced intercolonial micro-defects act as weakest links or fracture promoters/initiators, thereby affecting the microstructural integrity of the wires.

The final aim of this paper is to study the microstructural changes in the necking region of progressively cold-drawn pearlitic steel wires by means of a thorough and detailed analysis of pearlite interlamellar spacing and Vickers micro-hardness in this special region. To this end, a set of progressively cold-drawn pearlitic steel wires belonging to a real manufacturing chain were subjected to standard tension tests, in such a manner that the tests were interrupted before the final fracture, i.e., the test development was aborted just at the necking instant. The microstructural changes during necking were evaluated by measuring the pearlite interlamellar spacing in the necking region, as well as the Vickers micro-hardness in the different points of it. The study of the afore-said microstructural changes preceding the final fracture was the final aim of the research, intending to determine the local areas in the necking region of the specimens in which microstructural changes are most evident, thereby affecting the local mechanical response of a specific cold-drawn steel at the moment of instability under load control during the standard tension test.

This article focuses on the analysis of the evolution of inclusions present in eutectoid pearlitic steel subjected to a real cold drawing process. To this end, wires belonging to different stages of the manufacture chain were studied, starting from an initial hot rolled bar (not cold drawn at all). In addition to the information obtained through visual inspection, a quantitative analysis of the microdefects generated by these inclusions was carried out. The analysis was performed using materialographic techniques, scanning electron microscopy (SEM) and the image analysis program (AnaliSYS 3.1^®).

Taking into account that accessibility is one of the most strategic and determining factors in economic models and that accessibility and tourism affect each other, we can say that the study and improvement of one of them involved the development of the other. Using network analysis, this study presents an algorithm for labeling the difficulty of the streets of a city using different accessibility parameters. We combine network structure and accessibility factors to explore the association between innovative behavior within the street network, and the relationships with the commercial activity in a city. Finally, we present a case study of the city of Avila, locating the most inaccessible areas of the city using centrality measures and analyzing the effects, in terms of accessibility, on the commerce and services of the city.