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Polyamide 12 (PA12) properties meet specific requirements for various applications in the automotive and aerospace industries. Bulk specimens made of PA12 and processed via the additive manufacturing technique such as selective laser sintering (SLS) present a layered structure. In case of structural applications, the fatigue performance of SLS PA12 parts is of vital importance and fatigue response studies in these type of materials are still scarce. Therefore, the purpose of this paper is to analyse the effect of the applied load orientation on the fatigue crack propagation behaviour of the layered structure of SLS PA12.

With the aim of understanding the effect of the applied load with respect to the layer orientation on the fatigue crack growth of SLS PA12, fatigue crack growth tests were carried out at two orientations. The specimens called PARA were orientated in such a way that the applied force direction belongs to the layer plane while in the group called PERP, the tensile force direction is coincident with the build direction, that is, perpendicular to the slice. Besides, special attention has been paid to the analysis of the fracture surfaces of the specimens, linking the micromechanisms of failure with the microstructure of the material.

The SLS PA12 specimens tested with the load applied parallel to the layered structure show a little better fatigue response than those tested at perpendicular orientation. The fracture surfaces of the specimens tested at perpendicular orientation are slightly smoother than those tested at parallel orientation. Crazes are the main micromechanism of failure with a crater size of 50 microns, which coincide with the spherulite size. This indicates that the void nucleation of the crazes takes places between lamellae inside the spherulites, and consequently, the craze growth and rupture occurs mainly in a transspherulitic mode.

PA12 parts manufactured via SLS are becoming more valuable in structural elements in the automative and aeronatical fields. In such applications, fatigue performance is vital for design. Fatigue studies are scarce in literature and even more when dealing with fatigue crack growth behaviour. The value of this work is the analysis of the fatigue crack growth response of these materials taking into account the anisotropic microstructure and to get a better understanding, this behaviour is explained taking into account the micromechanisms of failure and the microstructure of the material.

Polyamide 12 (PA12) processed by the additive manufacturing technique of selective laser sintering (SLS) is acquiring a leading role in cutting-edge technological sectors pertaining to transport and biomedical among others. In many of these applications, design requirements must ensure fatigue structural integrity. One of the characteristic features of these SLS PA12 is the layer-wise structure that may influence the mechanical response. Therefore, this paper aims to assess the fatigue life behavior of PA12, focusing on the effect of the load direction with respect to the load orientation.

With the aim of analyzing the effect of the load direction with respect to the layer wise structure, fatigue tests on plain samples of SLS PA12 were carried out with the load applied parallel and perpendicular to the layer planes. The S-N stress life curves and the fatigue limit at 106 cycles were determined at room temperature and at a stress ratio of 0.1. The fracture surfaces were inspected to evaluate the damage evolution, modeled via the fracture mechanics methodology to obtain the fracture parameters.

The fatigue resistance was better when the load was applied parallel than when was applied perpendicularly to the layered structure. The analysis of the postmortem specimens evidenced three regions. The inspection of the fatigue macro crack growth region revealed that crazing was the mechanism responsible of nucleation and growth of damage till a macroscopic crack was generated, as well as of the consequent crack advancement. The calculated fracture parameters computed from the application of the fracture mechanics approach were similar to those obtained from standardized fracture tests, except when the stress levels were close to the yield strength.

The fatigue knowledge of polymers, and especially of polymers processed via additive manufacturing techniques, is still scarce. Therefore, the value of this investigation is not only to obtain fatigue data that could be used for structural design with SLS PA12 materials but also to advance in the knowledge of damage evolution during the fatigue process.

This exploratory study aims to examine how online mentoring was provided through social media to support potential first‐generation Latino college students during their final year of high school and their transition into a two‐year or four‐year institution.

Using a one‐year qualitative study design, data were collected through interviews, surveys, and archived interactions on Facebook. Discourse analysis was used to code for types of social, informational, and emotional support provided.

Findings suggest that online mentoring through social media is a support system that the focal students turned to primarily for informational support, rather than for social or emotional support, and its impact seems to be contingent on the existence of conventional mentoring structures of high school counsellors, peers, and family.

High school counsellors and mentors in college outreach programs can leverage students’ presence in social media forums such as Facebook to help structure informational support (application deadlines, financial aid forms, contact information for college outreach) to help students prepare for and transition into college.

The visibility and amplification of information delivered through social media provides an untapped resource for assisting first‐generation college students in navigating the complex financial and logistical steps in transitioning to college. Its use as an additional tool for counsellors and mentors could increase matriculation and retention rates.

High school counsellors and directors of college outreach and mentoring programs could draw on findings in this paper when considering ways to integrate innovative approaches to providing mentoring support.

The functional strategy map (FSM) is a tool used to capture the organizations' supply chain strategy. Its product, the strategy map, allows the organizations to apply the Conceptual System Assessment and Reformulation methodology (CSAR) with a multi-objective perspective to rethink the business strategy. The aim of this study is to optimize a company business strategy of corrugate cardboard boxes, with its strategic and tactical relations and problems obtained with the CSAR methodology and the FSM tool, as well as its operational priorities identified by the analytical hierarchy process, which is a tool to support multicriteria decision-making. This proposal, with a mixed methodology approach, generates multiple improvements, such as the reduction of the overall cost, the optimal fill rate operations, and the articulation of the strategic and functional decisions in this organization, which are based on a cost competitive strategy. The results were validated by the financial assessments that ensure an attractive return of the investment and the articulation between the business strategies with its functional plans.

This chapter examines the framing of the Black Lives Matter (BLM) Movement in mainstream media. An analytic sample of 4,303 articles collected from the Dow Jones Factiva database reveals variation in depth, breadth, and intensity of BLM coverage in the following newspapers between 2012 and 2016: The St. Louis Post-Dispatch, The New York Times, The Washington Post, The Wall Street Journal, and Al Jazeera English. We review contemporary literature on racial inequality and employ Media Framing and Critical Race Theory to discuss the implications of our findings on public perceptions, future policy formation, and contemporary social protest worldwide.

Both Bolivia and Uruguay broke ranks with the global drug prohibition regime by introducing novel drug policies. State control of the production and supply of coca and cannabis represents a clear departure from both the spirit and the letter of the international drug conventions. Although, the rationale, processes and outcomes of policy change were distinctive in many regards, this chapter posits that there are conceptual resemblances. In both countries, the leadership of a charismatic and idiosyncratic president has to be considered. Furthermore, in both countries, mobilisation and activism were also decisive. Lastly, in both countries novel drug policy responded to specific problems that decision-makers faced. Approaching drug policy reforms in Bolivia and Uruguay in terms of personal leadership, mobilisation and policy problems provides a useful analytical first-cut to assess the continuity and change in drug policy observable elsewhere. Additionally, scrutinising the reasons and motivations for undertaking drug policy reform also allows to better understand each country’s behaviour on the international stage.

Purpose: This paper uses performance theory to explore how wine-tourism experiences are orchestrated by wine tour guides to encourage engagement of consumers. It describes how such orchestration is built on material elements such as landscapes, architecture, vineyards, production facilities, and wine tastings.

Design/methodology/approach: A multi-layer ethnographic research on wine-tourism was employed. The interviews, observations, and field notes were analyzed through the lens of performance theory. A constant comparative method was used to identify emergent patterns, and a hermeneutic method was used to interpret the data.

Findings: The paper builds on performance theory and delineates the ways in which guides co-create intense experiences with participants. It portrays how tour guides often adjust their theatrical scripts to consumers’ unique needs through creative variations: surprise treats, activities, and personal stories. When guides take pleasure in tours, participants do as well, resulting in memorable co-created experiences. The tours feature processes such as pitching and relation-building techniques that call upon identity, morality, and materiality scripts, which ultimately build a sense of social obligation among participants toward tour guides and winery staff.

Originality/value: From a theoretical perspective, the paper adds value to the discussion of performance in tourism by suggesting that the service blueprint, architecture, and employee training are only part of the story. This paper shows how consumer engagement and interactions between participants, guides, architecture, and landscapes are essential elements of memorable experiences.

Research limitations: Like other studies, there are limitations to our study as well. Our study only included one-day wine tours. A broader investigation of strategic alliances between tour companies and wineries, and how wine tourists experience and sustain a sense of social obligations to the wineries they visit, will provide further insights into how wine-tourism functions as a co-creative emergent form of consumption involving individuals, products, and processes.

Adolescent mental health is a global concern. There is an urgent need for creative, multimedia interventions reflecting adolescent culture to promote mental health literacy and well-being. This study aims to assess the impact of a film-based intervention on adolescent mental health literacy, well-being and resilience.

A pretest-posttest intervention with a multi-methods evaluation was used. A convenience sample of ten schools facilitated students aged 15–17 years to engage in an online intervention (film, post-film discussion, well-being Webinar). Participants completed surveys on well-being, resilience, stigma, mental health knowledge and help-seeking. Five teachers who facilitated the intervention participated in post-implementation interviews or provided a written submission. Analysis included paired-t-test and effect size calculation and thematic analysis.

Matched pretest-posttest data were available on 101 participants. There were significant increases in well-being, personal resilience and help-seeking attitudes for personal/emotional problems, and suicidal ideation. Participants’ free-text comments suggested the intervention was well-received, encouraging them to speak more openly about mental health. Teachers similarly endorsed the intervention, especially the focus on resilience.

Intinn shows promise in improving adolescents’ mental health literacy and well-being. Film-based interventions may encourage adolescents to seek professional help for their mental health, thus facilitating early intervention.

Since the development of the COVID-19 vaccinations, questions surrounding race have been prominent in the literature on vaccine uptake. Early in the vaccine rollout, public health officials were concerned with the relatively lower rates of uptake among certain racial/ethnic minority groups. We suggest that this may also be patterned by racial/ethnic residential segregation, which previous work has demonstrated to be an important factor for both health and access to health care.

In this study, we examine county-level vaccination rates, racial/ethnic composition, and residential segregation across the U.S. We compile data from several sources, including the American Community Survey (ACS) and Centers for Disease Control (CDC) measured at the county level.

We find that just looking at the associations between racial/ethnic composition and vaccination rates, both percent Black and percent White are significant and negative, meaning that higher percentages of these groups in a county are associated with lower vaccination rates, whereas the opposite is the case for percent Latino. When we factor in segregation, as measured by the index of dissimilarity, the patterns change somewhat. Dissimilarity itself was not significant in the models across all groups, but when interacted with race/ethnic composition, it moderates the association. For both percent Black and percent White, the interaction with the Black-White dissimilarity index is significant and negative, meaning that it deepens the negative association between composition and the vaccination rate.

The analysis is only limited to county-level measures of racial/ethnic composition and vaccination rates, so we are unable to see at the individual-level who is getting vaccinated.

We find that segregation moderates the association between racial/ethnic composition and vaccination rates, suggesting that local race relations in a county helps contextualize the compositional effects of race/ethnicity.