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The purpose of this study is to explore the optimum design of bending plate compliant mechanisms subjected to pure mechanical excitations using topological-derivative-based topology optimization. The main objective is to design the reinforcement in a plate of base material.

The optimum design is performed by means of a level-set representation method guided by topological derivatives. Kirchhoff and Reissner–Mindlin models are used to solve the linear bending plate problem. A qualitative comparison has been carried out between the optimal obtained topologies for each model.

The proposed methodology was able to design reinforcement in a plate of the base material. The obtained reinforcements notably improve the device’s behavior. The shape and topology of the reinforcements vary depending on the mechanical plate model considered. In fact, in the Reissner–Mindlin solutions, very thin flexo-torsional hinges connecting big zones of the reinforcement material are designed.

Up to date, the synthesis of ortho-planar mechanisms by means of continuum topology optimization was only boarded within a multi-physics context. In this work, the optimal design of pure ortho-planar compliance actuators is addressed. The best performance is found by analyzing the results for two classical mechanical plate models.

This study aims to estimate the overall SARS-CoV-2 seroprevalence and evaluate the accuracy of an antibody rapid test compared to a reference serological assay during a COVID-19 outbreak in a prison complex housing over 13,000 prisoners in Brasília.

The authors obtained a randomized, stratified representative sample of each prison unit and conducted a repeated serosurvey among prisoners between June and July 2020, using a lateral-flow immunochromatographic assay (LFIA). Samples were also retested using a chemiluminescence enzyme immunoassay (CLIA) to compare SARS-CoV-2 seroprevalence and 21-days incidence, as well as to estimate the overall infection fatality rate (IFR) and determine the diagnostic accuracy of the LFIA test.

This study identified 485 eligible individuals and enrolled 460 participants. Baseline and 21-days follow-up seroprevalence were estimated at 52.0% (95% CI 44.9–59.0) and 56.7% (95% CI 48.2–65.3) with LFIA; and 80.7% (95% CI 74.1–87.3) and 81.1% (95% CI 74.4–87.8) with CLIA, with an overall IFR of 0.02%. There were 78.2% (95% CI 66.7–89.7) symptomatic individuals among the positive cases. Sensitivity and specificity of LFIA were estimated at 43.4% and 83.3% for IgM; 46.5% and 91.5% for IgG; and 59.1% and 77.3% for combined tests.

The authors found high seroprevalence of anti-SARS-CoV-2 antibodies within the prison complex. The occurrence of asymptomatic infection highlights the importance of periodic mass testing in addition to case-finding of symptomatic individuals; however, the field performance of LFIA tests should be validated. This study recommends that vaccination strategies consider the inclusion of prisoners and prison staff in priority groups.

Customer identification leads to behaviors that are beneficial for firms. This paper aims to analyze the effect of firm identification and community identification on content creation, which indirectly may affect offline word of mouth and online word of mouth.

This paper proposes a research model that is tested using data from 491 users of online travel agencies. To do so, partial least squares method is used.

The results show a positive relationship between firm identification and community identification. Moreover, both variables exert a positive effect on content creation. Furthermore, content creation positively influences offline and online word of mouth. This influence is moderated by self-enhancement in the case of online word of mouth.

Firm managers must enhance customer identification, as it can turn in behaviors that are beneficial for the company. Moreover, firms that own online communities must apply segmentation strategies based on identification and self-enhancement to encourage positive behaviors from customers.

This research tests the relationship between firm identification and community identification. Additionally, this study jointly analyzes the impact of these variables on several beneficial behaviors.

La identificación del consumidor genera comportamientos que son beneficiosos para las empresas. Esta investigación analiza el efecto directo de la identificación con la compañía y la identificación con la comunidad sobre la creación de contenido, así como el efecto indirecto de estas variables de identificación sobre el boca- oído offline y online.

Esta investigación propone un modelo teórico, el cual es estimado mediante Partial Least Squares a partir de información procedente de 491 usuarios de agencias de viajes online.

Los resultados muestran una relación positiva entre la identificación con la firma y la identificación con la comunidad. Además, ambas variables ejercen un efecto positivo en la creación de contenido. Asimismo, la creación de contenido influye positivamente sobre el boca-oído offline y online. Esta influencia es moderada por la necesidad de reconocimiento de los consumidores.

Los resultados del trabajo recomiendan potenciar la identificación del cliente con la empresa, dado esta identificación conlleva comportamientos beneficiosos para la compañía. Además, las compañías que poseen comunidades online deberían aplicar estrategias de segmentación basadas en la identificación y la necesidad de reconocimiento de cara a potenciar que sus clientes llevan a cabo comportamientos positivos para la empresa.

Esta investigación examina la relación entre la identificación con la compañía y la identificación con la comunidad. Adicionalmente, este estudio analiza conjuntamente el impacto de estas variables en comportamientos que son beneficiosos para la empresa

Trabajo de investigación

On 1 January 1929, Augusto César Sandino wrote his now famous declaration that aptly summarizes both the Sandino and the Frente Sandinista de Liberatión Nacional (FSLN, the Sandinista National Liberation Front) positions on the issue of foreign domination. He issued the statement in response to a letter from the officer commanding American forces in Nicaragua, Admiral D. F. Sellers. When Sellers suggested that Sandino's resistance would serve “no useful purpose,” Sandino replied:

COVID-19 played a crucial role in the development and enlargement of learning via electronic media. Still, the recent fourth industrial revolution [Industry 4.0 (I4.0)] paved the road toward Education 4.0. In this regard, several research challenges arise, involving the preparation of gamification strategies in online learning environments. In this sense, this paper aims to investigate the relationship between technologies of I4.0 and gamification practices in online learning around the world. Specifically, to categorize the studies of the scientific literature in the area into knowledge domains and the mention of I4.0 technologies and to verify the relationship of these technologies with the different educational levels.

The preferred reporting items for systematic reviews and meta-analysis protocol was used as a research method with 130 papers included for full content analysis and obtained from the Web of Science.

The leading I4.0 technologies mentioned in the analyzed papers were simulation, Internet of Things and augmented/virtual reality, in this order. Although there are more mentioned technologies, the domain of knowledge to be applied and the educational level interfere in choosing these pillars. With this, the main findings of this relationship were exposed in a singular, modern, active, realist, technological framework to demonstrate how I4.0 relates to the practice of gamification in online educational environments.

To the best of the authors’ knowledge, this is the first study that brings together the relationship of gamification applied in e-learning with I4.0 technologies.

In this chapter, I examine how religion can serve as an ideology that has the capacity to bridge people of the same faith who hold divergent political stances. Building on Williams’ work (1996), I propose that religion operates as an ideology when it diagnoses the source of social conflicts, proposes solutions, and justifies action. Yet religious ideological appeals are not always effective at bridging political divides. Thus the key question of this study is: under what social conditions are religiously-based ideological appeals effective at winning people’s support for social and political movements? To address this, I examine the relationship of religious leaders to Latin American movements that aimed to nonviolently overthrow authoritarian states. In particular, I analyze the conditions that led some religious elites to become pro-revolution while others sided with the incumbent regime. Using comparative historical methods, I analyze the different political stances of the Catholic Church hierarchy in the 1970s–1980s in Chile (where the church opposed the dictatorship), Argentina (where the church was largely supportive of the regime), and El Salvador (where the church hierarchy was divided). I argue that ideological appeals for religious leaders’ support are most effective when the religious institution receives no financial or political benefits from the regime and when leaders have relational ties to the aggrieved. Two factors had mixed effects on the decision to remain loyal to the state or not; these include the presence of an armed radical flank, and the state’s use of indiscriminate repression.

The purpose of this paper is to demonstrate the utility of combining event-centred and variable-centred approaches when analysing big data for higher education institutions. It uses a large, university-wide data set to demonstrate the methodology for this analysis by using the case study method. It presents empirical findings about relationships between student behaviours in a learning management system (LMS) and the learning outcomes of students, and further explores these findings using process modelling techniques.

The paper describes a two-year study in a Chilean university, using big data from a LMS and from the central university database of student results and demographics. Descriptive statistics of LMS use in different years presents an overall picture of student use of the system. Process mining is described as an event-centred approach to give a deeper level of understanding of these findings.

The study found evidence to support the idea that instructors do not strongly influence student use of an LMS. It replicates existing studies to show that higher-performing students use an LMS differently from the lower-performing students. It shows the value of combining variable- and event-centred approaches to learning analytics.

The study is limited by its institutional context, its two-year time frame and by its exploratory mode of investigation to create a case study.

The paper is useful for institutions in developing a methodology for using big data from a LMS to make use of event-centred approaches.

The paper is valuable in replicating and extending recent studies using event-centred approaches to analysis of learning data. The study here is on a larger scale than the existing studies (using a university-wide data set), in a novel context (Latin America), that provides a clear description for how and why the methodology should inform institutional approaches.

The purpose of the paper is to describe the development and implementation of a specialized Virtual Learning Environment (VLE) designed to enhance the knowledge and skills related to sustainability in students with Down syndrome. This VLE serves as a means to make sustainable concepts more accessible and comprehensible to this specific student group, with the aim of promoting their engagement and understanding of sustainability, environmental awareness, recycling, and sustainable construction. The ultimate goal is to empower students with Down syndrome by providing them with a tailored educational tool that facilitates their learning in a manner that is engaging and effective.

The approach outlines the overarching plan for creating the e-learning platform, including the technological choices and design considerations necessary to make it effective and accessible for students with Down syndrome. It's a fundamental component of the methodology, as it sets the direction for the platform's development and aligns with the objectives of the study. And also encompass the strategy for teaching and learning sustainability aspects to students with Down syndrome.

Positive Feedback from Tutors and Professionals: The feedback from tutors and professionals is generally positive, with 91.4% finding the platform to be well-organized and 88.6% considering the content adequate and understandable. This suggests that the VLE met the needs and expectations of educators and professionals involved in the learning process. Utility for Professional Practice: Approximately 80% of tutors and professionals found the platform useful for their professional practice, indicating that it has practical applications beyond student learning. This information highlights the success and potential impact of the VLE for this specific target group.

The study may not have explored the depth of sustainability concepts covered within the VLE. Future research could delve into the specifics of the content and its effectiveness in teaching complex sustainability topics.

The incorporation of universal design principles in the VLE development could serve as a model for creating inclusive e-learning platforms. This has broader implications for improving digital accessibility in education. The positive feedback from tutors and professionals suggests the importance of interdisciplinary collaboration in education. Professionals from various fields, including special education and sustainability, can work together to create effective and inclusive learning tools.

This study can contribute to the broader discussion on inclusive education and the effective use of technology to enhance learning experiences for individuals with disabilities.

The study addresses a crucial gap in the field of sustainability education by focusing on students with Down syndrome. It highlights the importance of making sustainability education inclusive and accessible to a diverse range of learners, including those with disabilities. This originality contributes to the broader discourse on inclusive education and environmental awareness. The development of a specialized Virtual Learning Environment (VLE) for this specific target group is an original contribution. It demonstrates the potential for adapting educational technology to meet the unique needs of students with Down syndrome, potentially serving as a model for future educational tool development.

This study explores the impact of the residents' voice and social media brand engagement on coopetition in tourism destinations with the mediating role of knowledge sharing. The study's statistical population includes tourists who visited Iran. The sample was 243 tourists who visited Iranian tourist different villages in the spring of 2023. This empirical study adopted a descriptive correlational method and used PLS3 for data analysis. The effects of residents' voices, knowledge sharing, and engagement with social media improve cooperation between tourism destinations, help create platforms for creativity and innovation in this industry, and ensure the promotion of sustainability and attractiveness of tourism. Therefore, the mutual analysis of the effects of different factors in rural tourism in Iran is valuable in providing a new method to improve the tourism experience in this field.

This research explores the paradigm of coopetition and the different theories that contribute to its evolution. The variation of cooperation and competition in a relationship depends on the resource flows identified in the literature. However, this research focusses on coopetition behaviours in the business world. Coopetition, simultaneous collaboration, and competition between firms, has emerged as a pivotal factor influencing organisational success in today's dynamic business environment. Based on game theory, the different types of competitive relationships between adversaries will also be presented in this chapter, where the interdependencies between the players and their choices to co-operate or compete are explored. Another perspective presented is how companies use game theory to achieve gains in both zero-sum and non-zero-sum games by changing the players, the perceptions of risk, the associated returns, and the rules and scope of the game. This chapter also will show the prisoner's dilemma applied to business practices. Finally, we present the ‘tit-for-tat’ theory of strategy. The conclusion underscores the need for organisations to navigate a delicate balance between collaboration and competition to thrive in a complex and interconnected tourism global marketplace.