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This study aims to develop and validate an integrated extrusion bioprinting system that produces planar and non-planar scaffolds with embedded living material (bacteria or mammalian cells), overcoming the limitation of traditional extrusion bioprinting, where the material is deposited and cultured in planar layers.

The bioprinting device was constructed by modifying a fused deposition modelling 3D printer, adapting the extrusion holder for hydrogel-bioinks, going from an 8-bit architecture to a 32-bit one andad hoc updating the firmware, increasing the processing capacity and enabling accurate deposition of material. The device performance was assessed in hydrogel 3D planar and non-planar extrusion, considering different radius of curvature to form porous scaffolds, evaluating their ability to retain the designed curved geometry and the cell viability maintaining in bacterial and mammalian cells bioinks.

The viability (up to 99%) and growth of bacteria and mammalian cells embedded in the scaffolds was confirmed by confocal microscopy. The suggested bioprinting platform and procedure integrates an efficient strategy for producing hydrogel-based scaffolds, obtaining 98% resolution in planar deposition. For non-planar scaffolds, it was found that they are capable of maintaining the designed curvature even after being removed from the support, with an 88% of resolution.

It is reported a novel and advanced 3D extrusion bioprinting strategy for producing curved and complex scaffolds, preserving resolution and sterile conditions, introducing in addition a methodology for direct design and generation of a g-code with continuous and smooth paths, pioneering on the 3D bioprinting of bacterial bioinks.

The braking system on motorcycles is of vital importance, taking into account that its operation is based on the friction between the surfaces in the contact that are found heat and, therefore, the brake liquid, the thermoelastic deformation on the contact surface, the degradation and failure of the material, as can be attributed to the safety of the occupants. The purpose of this paper is to perform mathematical calculations regarding the phenomena of the transfer of heat generated in the brake system.

Using SolidWorks simulation software, the geometric model of the three disc brakes of the different cylinders was carried out to identify the elements with the variations of the maximum temperature, and the verification with the calculations was made under ideal condition (80 Km/h and 12°C).

The results obtained show that with the mathematical calculations it was possible to validate the correct functioning of the braking system under different operating conditions, the systems that have higher capacity of displacement generate higher heat loss at higher speed so that their time of cooling according to Newton is major.

Through the analysis of finite elements, it was possible to identify that the braking system in severe working conditions is not overheated, assuring a natural convection cooling in approximately 12 min according to the mathematical calculations made.

The purpose of this paper is to present a methodology for forecasting the availability off-highway trucks used in a fleet for large transport operations of ore and sterile rock from an open pit mine.

This methodology enables the estimation of the number of hours of preventive and corrective maintenance required, which are used to predict truck availability. The authors used historical data for the maintenance strategy based on the hours of operation.

These data are statistically analyzed to obtain the key quantities and statistical models required to project availability and to develop equipment replacement plans.

A methodology for forecasting availability to assets in open pit mining industry was implemented.

The purpose of this paper is to describe and analyse a teaching strategy designed to increase the awareness of trainee teachers and educate them with regard to sustainable consumption.

Ninety-four subjects (trainee teachers) were assessed on their knowledge of the environmental impacts of consumerism, their attitudes to sustainable consumption and their behavioural intentions before (pre-test) and after (post-test) the teaching intervention took place.

Statistical analysis of the results obtained revealed that subjects increased their knowledge of the social and environmental impacts of consumerism, became more aware of the need to take action in this regard, and developed behaviours oriented towards a sustainable model of consumption.

The proper application of an educational strategy of this nature requires more time than that actually assigned to the teaching intervention itself. This obstacle was overcome by using the time envisaged by the European Space for Higher Education, but the outcome could not be monitored.

A reduction of individual and collective consumption in universities.

The study demonstrates the possibilities of an educational strategy that when applied to trainee teachers in higher education promotes sustainable consumption.

The purpose of this paper is to report the study of vibration energy harvesting from a data center (DC) mainframe computer to power nodes of a wireless sensors network (WSN are used to improve the energy efficiency of a DC).

The piezoelectric vibration energy harvester (VEH) has been designed using an electromechanical analytical model. The VEH is composed of a three-layer cantilever beam with a tip mass. A vibration map (amplitude and acceleration) is presented and the authors show that the optimum frequency is around 90 Hz with maximum amplitude of 1 μm and maximum acceleration of 0.6 m/s2. Modeling results and experimental measurements using an electromagnetic shaker to apply vibrations concord.

The VEH delivers a maximum power of 31 μW on a DC mainframe computer and 2.3 mW at 1g on a test rack. It allows us to use a storage capacitance to successfully power a wireless sensor node for measuring temperature. This paper has been carried out in cooperation with IBM Montpellier and within the framework of the RIDER project financed by the French government and the European Union.

A vibration map (amplitude and acceleration) is presented and the authors show that the optimal frequency is around 90 Hz with maximum amplitude of 1 μm and maximum acceleration of 0.6 m/s2. The VEH delivers a maximum power of 31 μW on DC mainframe computer and 2.3 mW at 1 g on test mounted the shaker. It allows us with a storage capacitance to successfully power a wireless sensor node for measuring temperature.

The purpose of this study is to analyze the relationship between academic writing and generative artificial intelligence (AI).

This paper is characterized as exploratory and descriptive, with a qualitative approach. Two approaches were used: the first, a narrative review of the literature with a systematic search from which a data collection stage was carried out using asynchronous interviews by means of an online questionnaire.

The results indicate that generative AI should be seen as a complementary tool for creative and critical academic writing. The data collected also highlighted issues related to academic dishonesty and the new type of plagiarism – plagiarism made possible by technologies – as well as issues of authorship and legitimacy of work carried out with AI and the loss of reflective and critical thinking and creativity.

The considerable increase in resources using AI in all dimensions of human life.

The impact that the use of generative AIs can have on the creation of knowledge and the dissemination of scientific research.

The impact that the use of generative AIs can have on the creation of knowledge and on the dissemination of scientific research.

The need for academia to anticipate the use of AI in academic writing and to incorporate its benefits into this process, especially considering researchers in training.

El objetivo de este artículo es analizar la relación entre la escritura académica y la inteligencia artificial generativa.

Este artículo se caracteriza por ser exploratorio y descriptivo, con un enfoque cualitativo. Se utilizaron dos enfoques: el primero, una revisión narrativa de la literatura con una búsqueda sistemática, a partir de la cual se llevó a cabo una etapa de recogida de datos mediante entrevistas asincrónicas a través de un cuestionario online.

Los resultados indican que la IA generativa debe considerarse una herramienta complementaria para la escritura académica creativa y crítica. Los datos recogidos también pusieron de manifiesto cuestiones relacionadas con la deshonestidad académica y el nuevo tipo de plagio, el plagio posibilitado por las tecnologías, así como cuestiones de autoría y legitimidad del trabajo realizado con Inteligencia Artificial, la pérdida de pensamiento reflexivo y crítico y la creatividad.

La necesidad de que el mundo académico se anticipe al uso de la IA en la escritura académica e incorpore sus ventajas a este proceso, considerando principalmente a los investigadores en formación.

El considerable aumento de los recursos que utilizan la IA en todas las dimensiones de la vida humana.

El impacto que puede tener el uso de las IA generativas en la creación de conocimiento y la difusión de la investigación científica.

El impacto que puede tener el uso de las IA generativas en la creación de conocimiento y la difusión de la investigación científica.

O objetivo deste artigo é analisar a relação entre a redação acadêmica e a inteligência artificial generativa.

Este artigo é caracterizado como exploratório e descritivo, com uma abordagem qualitativa. Foram usadas duas abordagens: a primeira, uma revisão narrativa da literatura com uma busca sistemática, a partir da qual foi realizada uma etapa de coleta de dados usando entrevistas assíncronas por meio de um questionário on-line.

Os resultados indicam que a IA generativa deve ser vista como uma ferramenta complementar para a redação acadêmica criativa e crítica. Os dados coletados também destacaram questões relacionadas à desonestidade acadêmica e ao novo tipo de plágio - o plágio possibilitado pelas tecnologias, bem como questões de autoria e legitimidade do trabalho realizado com a Inteligência Artificial, a perda do pensamento reflexivo e crítico e da criatividade.

A necessidade de a academia antecipar o uso da IA na redação acadêmica e incorporar seus benefícios nesse processo, considerando principalmente pesquisadores em formação.

O aumento considerável de recursos usando IA em todas as dimensões da vida humana.

O impacto que o uso de IAs generativas pode ter sobre a criação de conhecimento e a disseminação de pesquisas científicas.

O impacto que o uso de IAs geradoras pode ter na criação de conhecimento e na disseminação de pesquisas científicas.

This paper aims to investigate the factors associated with the voluntary disclosure of integrated reporting (IR) in Brazil of the companies listed on the stock exchange – Brasil, Bolsa, Balcão. The cultural dimensions of a nation reflect different priorities in accounting practices. The Brazilian case, therefore, becomes significant, as Brazil is increasingly important in world markets.

As an explanatory econometric model, multinomial logistic regression was used (Y = 2 to describe the probability of the IR disclosure; Y = 1 to describe the occurrence of reports with practices similar to the IR and Y = 0 to describe the occurrence of non-disclosure of non-financial reports). Applied to panel data with random effects (chosen for best performance) in the period from 2016 to 2019.

Reveals the positive association of the company’s profitability and market-to-book with the probability of the IR disclosure. Regarding the board composition, it is suggested that size does not make a difference, with the greater participation of women and independence of directors associated with better probabilities of adopting the IR in Brazil.

This work is the first to characterize the Brazilian reality of voluntary disclosure, specifying the implementation of IR, compared to publishing reports similar to the IR and not reporting structured non-financial statements. It can also be considered the first study on the relevance of the board structure in the disclosure of IR by Brazilian companies. Finally, it contributes to the literature on IR adoption, bringing practical results in understanding the most favorable conditions in which the IR framework will be fully implemented.

Free guided walking tours are one of the most successful tourism segments in the digital platform economy. It is beginning to be associated with negative impacts in some of the destinations where it is spreading rapidly. Although the platform economy is generating increasing academic interest, the free tour model remains largely unexplored area in the literature. This study aims to examine how such activity affects cultural destinations.

Focussing on the largest Free Tours platform operating in Spain, GuruWalk, the methodology used analyses its impact in six cultural destinations on two of the sustainability dimensions: the territorial dimension and the governance, through an exploratory study.

The findings help to understand the differences that such activity generates in each destination depending on the phase of its life cycle, and to implement, if necessary, corrective measures. The research confirms that the impacts differ according to the tourist destination’s maturity, concluding that such activity contributes to the increase of tourist agglomerations and the overcrowding of cultural destinations in their middle and mature life cycles. The findings highlighted the importance of the role of local governance on free tour activity.

The main contribution is the association of the impacts they produce (especially in terms of massification) with destination life cycle phases. There were no similar precedents with a spatial or territorial analysis to reliably demonstrate not only that this activity has an impact on the territory but also what type of impact is produced.

The purpose of this paper is to explore the extent of the urban tourism literature that uses the systems approach to outline its research trajectory and detect its trends. Urban tourism is a complex phenomenon whose complexity increases at the very moment it interacts with complex environments. To deal with this kind of issues, urban tourism-related authors have used different approaches, with the systems approach being one of the best alternatives for its understanding and study.

A systematic literature review was conducted using two sets of keywords related to urban tourism and systems approach. Scopus, ScienceDirect and Web of Science databases were used for the peer-reviewed literature search. After filtering processes were applied, 29 publications were retained for the analysis.

This paper provides a significant overview of the existing publications regarding this topic. A theme of common interest and trends for future investigations were detected. Based on the findings, future works to be developed with the use of the systems approach, and its tools are proposed.

This review gives promising evidence on that the use of the systems approach for future urban tourism studies is a viable alternative to the application of other dominant approaches, to manage the complexity, diversity and dynamism of the urban tourism and of its environment, which is nowadays addressed as Smart. Then, the paper seeks to foster the use of systems approach and its systemic tools for the understanding and study of urban tourism as a complex system.