The presence of the gift in the life of the residents of the popular neighborhood George Américo de Feira de Santana - BA: from the formation of the neighborhood to the present day: A presença da dádiva na vida dos(as) moradores(as) do bairro popular George Américo de Feira de Santana – BA: da formação do bairro aos dias atuais

After a brief memory of the gift rank, we seek of reflecting on its presence in the formation and daily life of the residents at the popular neighborhood George Américo in Feira de Santana - BA. Based on reports collected by interviews carried out with residents and religious leaders of five religious denominations, located since the beginning in that geographic space and in which they settled in later on, we seek to identify ways in which the gift was made and is still present in the daily life of the relationships experienced there

A review on the use of finite element simulations for structural analyses of coronary stenting: What can we do nowadays and what do we need to move forward?

In silico studies to perform structural analyses of coronary stenting have attracted the attention of many researchers in the last 25 years. As a consequence, the finite element models used to describe the fundamental elements of stenting simulations, namely the delivery system (consisting of stent and balloon), the diseased artery, and the deployment procedure have had considerable development, paving the way for the application of numerical analyses in both manufacturing and clinical contexts. Indeed, in accordance with the logic of the 3Rs (refine, reduce, and replace), simulations can play a fundamental role in developing new devices and as a support tool for training/education and operational planning activities for clinical personnel. However, the application of such numerical methodologies in the aforementioned contexts of use requires an adequate level of credibility of the models with respect to the risk associated to their use in the decision-making process. Within this framework, this paper proposes a review of the modeling approaches available today for in silico stenting of coronary arteries and a discussion of their actual or potential application areas. In particular, the attention is focused on the different levels of credibility required by the presented contexts of use with respect to the validation activities of numerical models developed up to now

Investigating Balloon-Vessel Contact Pressure Patterns in Angioplasty: In Silico Insights for Drug-Coated Balloons

: Drug-Coated Balloons have shown promising results as a minimally invasive approach to treat stenotic arteries, but recent animal studies have revealed limited, non-uniform coating transfer onto the arterial lumen. In vitro data suggested that local coating transfer tracks the local Contact Pressure (CP) between the balloon and the endothelium. Therefore, this work aimed to investigate in silico how different interventional and device parameters may affect the spatial distribution of CP during the inflation of an angioplasty balloon within idealized vessels that resemble healthy femoral arteries in size and compliance. An angioplasty balloon computational model was developed, considering longitudinal non-uniform wall thickness, due to its forming process, and the folding procedure of the balloon. To identify the conditions leading to non-uniform CP, sensitivity finite element analyses were performed comparing different values for balloon working length, longitudinally varying wall thickness, friction coefficient on the balloon-vessel interface, vessel wall stiffness and thickness, and balloon-to-vessel diameter ratio. Findings indicate a significant irregularity of contact between the balloon and the vessel, mainly affected by the balloon's unfolding and longitudinal thickness variation. Mirroring published data on coating transfer distribution in animal studies, the interfacial CP distribution was maximal at the middle of the balloon treatment site, while exhibiting a circumferential pattern of linear peaks as a consequence of the particular balloon-vessel interaction during unfolding. A high ratio of balloon-to-vessel diameter, higher vessel stiffness, and thickness was found to increase significantly the amplitude and spatial distribution of the CP, while a higher friction coefficient at the balloon-to-vessel interface further exacerbated the non-uniformity of CP. Evaluation of balloon design effects revealed that the thicker tapered part caused CP reduction in the areas that interacted with the extremities of the balloon, whereas total length only weakly impacted the CP. Taken together, this study offers a deeper understanding of the factors influencing the irregularity of balloon-tissue contact, a key step toward uniformity in drug-coating transfer and potential clinical effectiveness

Finite element evaluation of the effects of faulting on a shallow tunnel in alluvial soil

A numerical estimation is presented on the effects induced in an existing tunnel by the development of a fault from the deep bedrock during a seismic event. The spreading of the fault within the alluvial deposit hosting the tunnel, and the consequent effects on its permanent liner, are studied in static conditions through a series of elastic-plastic, plane strain finite element analyses. They account for the reduction of the shear strength and stiffness characteristics of the faulting zone with increasing irreversible strains. Even though the calculations require only ‘‘standard’’, e.g. peak and residual, material parameters it is shown that these properties can hardly be obtained for the alluvial deposit at hand. To overcome this drawback a relatively large scale insitu tests could be performed and its results could be interpreted through a suitable back analysis. This would permit characterizing the numerical model to be subsequently adopted for the analysis of the faulting process