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This study aims to propose and numerically assess different ways of discretising a very weak formulation of the Poisson problem.

We use integration by parts twice to shift smoothness requirements to the test functions, thereby allowing low-regularity data and solutions.

Various conforming discretisations are presented and tested, with numerical results indicating good accuracy and stability in different types of problems.

This is one of the first articles to propose and test concrete discretisations for very weak variational formulations in primal form. The numerical results, which include a problem based on real MRI data, indicate the potential of very weak finite element methods for tackling problems with low regularity.

During a fall, a significant part of the major forces is absorbed by the dorsolumbar column area. When the applied stresses exceed the yield strength of the bone tissue, fractures can occur in the vertebrae. Vertebral fractures constitute one of the leading causes of trauma-related hospitalizations, accounting for 15% of all admissions. Posterior pedicle screw fixation has become a common method for treating burst fractures. However, physicians remain divided on the number of fixed segments that are needed to improve clinical outcomes. The present work aims to understand the biomechanical impact of different fixation methods, improving surgical treatments.

A finite element model of the dorsolumbar spine (T11–L3) section, including cartilages, discs and ligaments, was created. The dorsolumbar stability was tested by comparing two different surgical orthopedic treatments for a fractured first lumbar vertebra on the L1 vertebra: the posterior short segment fixation with intermediate screws (PSS) and the posterior long segment fixation (PL). Distinct loads were applied to represent daily activities.

Results show that both procedures provide acceptable segment fixation, with the PL offering less freedom of movement, making it more stable than the PSS. The PL approach can be the best choice for an unstable fracture as it leads to a stiffer spine segment.

This study introduces a novel computational model designed for the biomechanical analysis of dorsolumbar injuries, aiming to identify the optimal treatment approaches within both clinical and surgical contexts.

Develop biodegradable meshes as a novel solution to address issues associated with using synthetic meshes for POP repair.

Computational models were created with variations in the pore geometry, pore size, filament thickness, and inclusion of filaments around specific mesh regions. Subsequently, one of the meshes was 3D printed to validate the results obtained from the simulations. Following this, a uniaxial tensile test was carried out on the vaginal tissue of a sow to compare with the simulations, to identify meshes that displayed behaviour akin to vaginal tissue. Finally, the most promising outcomes were compared with those of the uterosacral ligament and a commercially available mesh.

Following a comprehensive analysis of the results, the mesh that most accurately replicates the behaviour of the vaginal tissue showcases a smaller pore diameter (1.50 mm), filaments in specific areas of the mesh, and variable filament thickness across the mesh. Nevertheless, upon comparing the outcomes with those of the uterosacral, the meshes do not exhibit similar behaviour to the ligament. Finally, the commercially available mesh does not represent the behaviour of both the vaginal tissue and the uterosacral ligament and in this sense may not be the best treatment option for POP repair.

Their biocompatibility and biomechanical properties make them a potential solution to the disadvantages of synthetic meshes. Personalized/customized meshes could be part of the future of surgical POP repair.

Adaptive load-bearing structures pursue the approach of saving mass within a load-bearing structure by adding external energy, thus saving materials and resources. This paper provides an overview of current research developments and shows some examples of existing prototypes.

First, basic terms and definitions from the research field of adaptive structures are introduced. After a brief historical insight, the numerical methods and prototypes used are presented as examples. The paper concludes with a summary of the state-of-the-art and open questions.

The current state of the art shows that the idea of adaptive structures offers great potential for more sustainability and resource efficiency in the construction industry. However, it also shows that research is still at the basic stage and that there are still some gaps in research.

The implementation of adaptive load-bearing structures is just one of many different approaches to greater sustainability in the construction sector. The issue of adaptive structures is a highly interdisciplinary field of research. The following paper is a literature review intended to summarize and critically evaluate the state-of-the-art research in this field. In the final section, some open questions are addressed, indicating that this research topic is still evolving.

In recent years, the emergence of Industry 4.0 technologies as a way of increasing productivity has attracted the attention of the manufacturing industry. This study aims to investigate the relationship between Industry 4.0 technologies and lean tools (LTs) by measuring how the internalisation of LTs influences the adoption of Industry 4.0 technologies and how the synergy between them helps improve productivity in European manufacturing firms.

Results from 1,298 responses were used to analyse linear regression and study the correlation between the use of LTs and Industry 4.0 technologies.

Results show that the companies analysed tend to implement more Industry 4.0 technologies when their level of lean internalisation is high.

This study provides useful information for managers of manufacturing firms by showing the correlation between LT internalisation and Industry 4.0 technologies, corroborating that optimal implementation of these technologies is preceded by a high level of LT internalisation. Furthermore, although there are studies showing the relationship between LTs and Industry 4.0 technologies, none consider the intensity of their implementation.

This study aims to identify the impact of restaurant pandemic mitigation measures on perceived service quality.

A total of 15,251 reviews were collected from 300 TripAdvisor Lisbon restaurant Web pages between March 2020 and December 2021, when Covid-19 contingency measures were in place. Grounded on the online reviews, a word frequency matrix was created and used as input on partial least squares–structural equation modeling to test the proposed hypotheses.

The results suggest that precaution measures, such as the Vaccination Certificate, negative tests and restaurant layout configuration, positively influenced perceived service quality and consumer satisfaction, moderated by consumers’ beliefs.

This study provides relevant information for restaurant managers, which will help them implement strategies to guarantee service quality, consumer satisfaction and revisit intentions in future pandemic scenarios.

This article presents two Brazilian Portuguese corpora collected from different media concerning public security issues in a specific location. The primary motivation is supporting analyses, so security authorities can make appropriate decisions about their actions.

The corpora were obtained through web scraping from a newspaper's website and tweets from a Brazilian metropolitan region. Natural language processing was applied considering: text cleaning, lemmatization, summarization, part-of-speech and dependencies parsing, named entities recognition, and topic modeling.

Several results were obtained based on the methodology used, highlighting some: an example of a summarization using an automated process; dependency parsing; the most common topics in each corpus; the forty named entities and the most common slogans were extracted, highlighting those linked to public security.

Some critical tasks were identified for the research perspective, related to the applied methodology: the treatment of noise from obtaining news on their source websites, passing through textual elements quite present in social network posts such as abbreviations, emojis/emoticons, and even writing errors; the treatment of subjectivity, to eliminate noise from irony and sarcasm; the search for authentic news of issues within the target domain. All these tasks aim to improve the process to enable interested authorities to perform accurate analyses.

The corpora dedicated to the public security domain enable several analyses, such as mining public opinion on security actions in a given location; understanding criminals' behaviors reported in the news or even on social networks and drawing their attitudes timeline; detecting movements that may cause damage to public property and people welfare through texts from social networks; extracting the history and repercussions of police actions, crossing news with records on social networks; among many other possibilities.

The work on behalf of the corpora reported in this text represents one of the first initiatives to create textual bases in Portuguese, dedicated to Brazil's specific public security domain.

The Third Sector has been receiving increasing attention from society, including academics, due to its importance in the face of the lack of government responses to many of the social problems that affect contemporary societies. Theoretically, the State is supposed to highlight the importance of the services provided by Social Solidarity Institutions, given their proximity to the beneficiaries, the efficiency in the distribution of resources and their innovative attitude towards social problems and needs. As a logical consequence, society is witnessing an increase in the participation of the private sector in social issues and a greater professionalisation of the Third Sector in the search for sustainability. Within the Third Sector, Social Solidarity Institutions play a very important role, acting as social actors. Within the environment of Social Solidarity Institutions, the Misericórdias also play a very important role. ‘Misericórdia’ is a non-profit institution that takes a form of charity, very popular in some countries, such as Italy and especially in Portugal. However, there are few studies on the governance conditions of this type of institution. In addition, it is possible to discuss whether there is any study that focuses specifically on this type of analysis. This study fills the empirical gap in the existing literature, providing an insight into the ways of adopting governance practices and principles within these institutions, which over five centuries of existence have continuously worked towards a more just, inclusive and supportive society.