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This paper aims to develop a novel strategy to manufacture poly-lactic acid (PLA) filaments reinforced with Mg particles for fused filament fabrication of porous scaffolds for biomedical applications.

The mixture of PLA pellets and Mg particles was extruded twice, the second time using a precision extruder that produces a filament with zero porosity, constant diameter and homogeneous dispersion of Mg particles. The physico-chemical properties of the extruded filaments were carefully analysed to determine the influence of Mg particles on the depolymerisation of PLA during high temperature extrusion and the optimum melt flow index to ensure printability.

It was found that the addition of a polyethylene glycol (PEG) plasticizer was necessary to allow printing when the weight fraction of Mg was above 4%. It was possible to print porous face-centre cubic scaffolds with good geometrical accuracy and minimum porosity with composite filaments containing PEG.

The new strategy is easily scalable and seems to be very promising to manufacture biodegradable thermoplastic/metal composite filaments for 3D printing that can take advantage of the different properties of both components from the viewpoint of tissue engineering.

This paper aims to analyze how Colombian Universities have incorporated the 2030 Agenda for sustainable development goals (SDGs) into their missions and visions.

The study used a documentary design to analyze the content of the missions and visions of the 86 Colombian Universities registered with the Ministry of National Education (MEN).

The study shows that universities are primarily aligned with Goal 13 as follows: climate action and this alignment is carried out to a great extent by the university’s governance, culture and activities. In contrast, there was a predominance of intentions to address the social dimension of sustainable development (SD).

The study focused on examining universities’ missions and visions, which leaves out other sources of information that could account for university practices linked to the SDGs and sustainability.

The study’s results reveal the degree to which the universities are aligned with the SDGs in Colombia, which serves as a basis for the formulation of guidelines by the MEN and other organizations to strengthen the processes that contribute to the 2030 Agenda.

Research on how universities align with the SDGs is not a new topic, but it is scarce in the Colombian context. This research contributes to this gap by addressing the topic from a holistic and comparative perspective of SD education.

Pulque is a fundamental piece in the Mexican gastronomy and identifying consumers’ perception could help promote it and generate new opportunities of commercialization. The purpose of this paper is twofold: first, to explore the underlying factors that influence consumers’ perception toward pulque, and second, to identify groups of consumers according to their perception.

A questionnaire was designed and applied to 220 consumers within points of sales. Exploratory factor analysis (EFA) was undertaken and hierarchical cluster analysis (HCA) was used to identify different groups of consumers.

By means of EFA three factors were obtained: traditionality, bad reputation of pulquerías and functional beverage. In order to identify different consumption patterns among consumers, HCA was performed and three groups were identified: traditional, neo-consumers and neo-consumers in transition. The groups identified showed significant differences in their perception.

Pulque has recently gained interest in various consumer sectors, mainly among young consumers, who are consuming and promoting the beverage these days. In this sense, the results of this work could be used for its promotion and consumption in order to attract more consumers and make a contribution to the development of local economies.

This is the first work in Mexico to explore the perception of consumers toward pulque: the most important traditional fermented beverage in Central México. Results of this research suggest the appearance of a revaluation process among young consumers, more informed and with greater sensitivity toward traditional Mexican food, particularly in the case of pulque. Likewise, these results could be useful for producers and sellers to carry out commercial strategies and promote the drink.

While previous studies have focused on the role of directors in the formation of transnational interlocks, this paper argues that firm strategy can also influence the development of these relationships. The purpose of this paper is to shed light on the practice of transnational interlocks by extending board interlocks theory from the national to the transnational context, and exploring aspects that are unique to the transnational level.

Based on the experiences of four British firms, this paper develops a conceptual framework that integrates under-examined dimensions of this networking practice at the organizational level of analysis, specifically degree of internationalization (DOI) and psychic distance (PD).

The paper argues that firms will increasingly engage in transnational interlocks as internationalization intensifies, and that expansion into psychically distant countries may result in further engagement in these connections. Further, firms will tend to form transnational received interlocks at their early stages of internationalization, and transnational sent and neutral interlocks at later stages of this process. It identifies four categories of firms: locals, extenders, explorers and cosmopolitans.

Directors can contribute to their firms’ success by interlocking with firms located in key foreign markets. Firms should also welcome directors with transnational board appointments to secure knowledge and resources overseas.

The manuscript contributes to our understanding of transnational interlocks by examining the independent and joint influence of the firm’s DOI and PD on the formation of such relationships.

This paper aims first to describe the most prevalent teachers’ and students’ behaviors in synchronous online classes in emergency remote teaching; second, to discern behavior profiles and third, to investigate what features explain the observed behaviors.

An adapted COPUS observation protocol was employed to observe 292 online classes from 146 higher education teachers.

The most prevalent behaviors were: Presenting for teachers and Receiving for students, followed by Teachers Guiding and Students Talking to Class. Furthermore, cluster analysis showed two groups: Traditional and Interactive. The variables that better explained belonging to the Interactive lecture group were disciplinary area – social sciences and humanities –and teaching in technical institutions.

In a context where higher education institutions intend to project the lessons learned into post-pandemic learning experiences, this study provides observational evidence to realize the full potential expected from online and blended teaching and learning.

Despite the prevalence of synchronous online lectures during COVID-19, there is a paucity of observational studies on the actual behaviors that occurred in this context. Most research has been based on surveys and interviews. This study addresses this gap.

The authors’ goal in this paper is to study if there are long-run effects on the wages of those workers who entered the labour market overeducated but who have, over time, been able to overcome this situation by obtaining a job for which they are correctly matched.

This study universe is constituted by workers entering the labour market with a university degree between 2004 and 2012. The age range of these individuals is between 22 and 35 years old. With the data of the 8,359 selected individuals, the authors have constructed a balanced panel covering the period 2013–2017. This methodology is developed in two steps. First, the authors estimate a wage equation with the traditional variables and, second, the authors use the estimated coefficients of these variables to predict the wage paths of a representative individual in each group.

The main result the authors obtain indicates that the wages of those who manage to overcome an initial situation of overeducation do converge but very slowly to the respective wages of those others that entered the labour market correctly matched from the beginning. The authors consider this result to point towards the existence of scarring effects in wages induced by an initial situation of overeducation. The authors also present evidence, beyond education, about the influence that the occupational characteristics that a worker has on wages.

The factors that can influence the catching-up of wages are multiple, and it is not feasible to test all of them empirically. Therefore, the wage convergence process the authors present may also be influenced by other variables for which the authors do not have information.

This paper contributes to different branches of the labour market. First, the authors present new evidence within the literature dealing with the so-called scarring effects on wages related to the conditions entering the labour market. Secondly, this study’s results provide a new argument that complements those developed so far that explain a reduction in the wage skill premium detected among young graduates in Spain. Finally, this paper contributes to advancing research about the effects that overeducation has on wages.

The question the authors are attempting to answer in this paper can be formulated in the following terms: when a worker manages to overcome an initial situation of overeducation, what happens to his/her wage? Will it adjust quickly to the new working situation, or will we observe a slow convergence to the wages of workers with an employment history without overeducation situations? To the best of the authors’ knowledge, this topic has not yet been studied. Researchers have mostly focused their attention on comparing the wages of overeducated workers with the wages of those who are correctly matched. In this case, the authors compare the wages of correctly matched workers, but with the difference that some were initially overeducated and others were not.

A mission statement is the central axis of any organization and the cornerstone of its strategic planning. Universities have implemented this tool to define, among other things, its identity; however, the legal nature and functions of the mission statement have not been determined. In this article, the authors analyze the differences in the university mission statements of public and private higher education institutions in relation to the mission functions proposed by the 1992 legislation on higher education in Colombia – Law 30 – involving teaching, research, extension and social projection and internationalization.

Through content analysis, the authors analyze the mission statements of two groups of institutions that make up the totality of universities in Colombia – 32 public and 53 private universities. The analysis is conducted along the four dimensions defined by the law as comprising the higher education mission, i.e. teaching, research, extension and social projection, and internationalization, due to its importance in the high-quality institutional accreditation process.

Based on the differences identified in the mission statements, the authors establish the university functions and determine how they give back to society in their legal capacity as public or private institutions.

This research scenario is appropriate for answering research questions related to whether there are differences in the strategies of Colombian public and private universities based on their mission statements. Although the Colombian higher education system includes various types of tertiary institutions, only universities are included in the study.

Research has shown that regardless of their legal nature, based on their mission statements, Colombian universities are mainly geared towards teaching. However, when comparing additional dimensions, private universities are less involved in research processes and more focused on activities related to social impact than are public universities. Additionally, private universities are more engaged in internationalization than are public institutions, with mission statements focused on both national and international accreditation processes.

The results of this research are intended to help society comprehend the differences between public and private universities in Colombia based on mission statements, which can contribute to understanding, among other factors, the academic programs offered by universities and how they should guide their activities.

This is the first such study in Colombia, a country that provides higher education through public and private institutions in very similar proportions, that analyses the differences in university mission statements and whose findings contribute to understanding whether universities are strategically oriented towards their own established policies or to contributing to the development of new public policies aimed at supporting the country's development process.

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 this study is to design and develop an environmentally controlled enclosure for commercial three-dimensional (3D) printers.

Computational fluid dynamics (CFD) simulations and experimental testing investigated various designs for environmentally controlled enclosures. CFD simulations provided the necessary information to select the optimal and feasible design, whereas experimental testing validated the CFD simulation results. An environmentally controlled environment allowed test samples to be printed at several relative humidity (RH) settings (20% RH, 50% RH and 80% RH). The test samples were characterized at both the macro and micro scales. The macroscale characterization was conducted using the static tensile testing procedure, while the microscale polymer material properties were determined using atomic force microscopy.

An environmentally controlled enclosure was designed and built to produce airflow in the print region with an average RH uniformity of over 0.70. Three batches of ASTM D638 standard test samples were printed at 20% RH (low RH), 50% RH (mid RH) and 80% RH (high RH). Macroscale characterization showed that the samples printed at lower humidity had statistically significantly higher tangent modulus, ultimate tensile strength and rupture strength. atomic force microscopy studies have also verified these results at the microscale and nanoscale. These studies also showed that a high humidity environment interacts with melted polylactic acid, causing additional surface roughness that reduces the strength of 3D-printed parts.

There is a need for stronger and higher-quality 3D-printed parts in the additive manufacturing (AM) market. This study fulfills that need by designing and developing an environmentally controlled add-on enclosure for the AM market.

Critique originated by earlier theorization of environmental accounting, as a way of building environmentalist visibility of business, led Gray et al., to study environmental accounting in the dynamics of organizational change. They concluded that environmental accounting is being used to “negotiate the conception of the environment” by companies that have not significantly changed. In order to investigate whether Gray et al.’s model and conclusions apply to a different cultural context, we have conducted nine case studies in Spain. We found that Spanish organizations are not truly changing their conventional perception of the environment, even in those cases where generalized structural and organizational changes are taking place. Moreover, the use of environmental accounting is coupled with an attempt to negotiate and control the environmental agenda.