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The mechanical characterization of selective laser melting (SLM) parts is an industrial challenge. This paper aims to propose a methodology to control the fatigue life of 17-4Ph stainless steel by selecting the most relevant manufacturing parameters: i.e. laser power, laser travel speed, hatch spacing and laser defocusing.

A rough and refined design of experiment (DOE) is carried out to target the best combination of process parameters. A response surface model is then constructed to predict the parameter combination that optimizes the fatigue performance.

This study results show that the fatigue limit of the specimens manufactured by SLM (471.7 MPa at 107 cycles) has reached near 90% of the value found in samples machined from a bar. This demonstrates the applicability of the method proposed to optimize the SLM process and control the fatigue life of 17-4Ph stainless steel. The study results are compared with other research works and provide an increase of 18% to the fatigue limit.

This study showcases a DOE methodology to optimize the SLM parameters to achieve fatigue performance as great as that of solid 17-4Ph stainless steel.

This paper aims to determine the long-term effect (at 15 months) of lockdown on occupational competence and values.

In total, 391 participants who participated in the first phase of the study (i.e. a previous study conducted during lockdown) were included. They completed an online version of the Occupational Self-Assessment. The results were compared with Phase 1 scores.

Occupational competence scores reduced during lockdown and increased 15 months later, but they did not return to pre-lockdown levels. The value score was lower 15 months after lockdown than pre-lockdown. The personal value system, which began to change during lockdown, was further changed at 15 months.

This study confirms that the spring 2020 lockdown had a long-term impact on occupational competence and values.

This study aims to examine the effects of front-of-package (FoP) labels on the healthy evaluation of Peruvian consumers. This relationship was examined in cases where snacks were healthy and unhealthy. In addition, the study included the role of three consumer purchase objectives (i.e. hedonic, healthy and weight loss) and two types of consumers (high and low use of labelling) in the healthy evaluation.

The sample consisted of 628 Peruvian youngsters aged between 16 and 24 years who frequently consume processed food. The research panel “QueOpinas” oversaw the recruitment of the participants through social media and television. Four types of FoP labels were studied in depth: Nutritional Warnings, Monochrome Guideline Daily Amount (GDA), Polychrome Guideline Daily Amount (GDA-Semaphore) and Traffic Light Labelling. A paired sample t-test and MANOVA were performed to evaluate the research objectives.

The GDA FoP label was found to be insufficient to promote a healthy evaluation. In contrast, the Nutritional Warnings and GDA-Semaphore and Traffic Light FoP labels had a significant and positive effect on the healthy evaluation of the snacks at a 95% confidence level. However, a comparative analysis of the labels revealed that some can be more efficient than others in promoting healthy purchase decisions. For the nutritional warnings (NWs) and traffic light FoP labels, the results revealed that consumers better distinguish unhealthy and healthy cereal bars when these products display traffic light labels.

This research topic has not been investigated in Peru and relevant research in this region is still incipient. In addition, the findings are important for policymakers as the findings will be able to implement specific labelling systems that will help consumers make healthier choices and support the debate about the effectiveness of the main FoP systems.

Purpose — Study the causal effect of psychological factors on mode choice, using an instrument which gathered attitudinal, affective and habitual behaviour factors, with an application to a Canadian and Chilean sample.

Approach — Ad hoc questionnaire used to collect information related to psychological factors, studying the role of these factors upon mode choice using structural equation modelling, combining a measurement model and the latent variables.

Findings — Emotional (affective) factors have a strong influence on mode choice, as well as attitudinal and habitual factors. Car users have a strong positive emotion to the transport mode they use when compared with public transport users and transit utilization.

Research limitations — The inclusion of social factors, such as norm, role and self-concept, is desirable for a better understanding of people's behaviour regarding transport mode usage. The structural equation modelling was used to analyse the causal effects among factors, but it is not intended to model mode choice. An advanced approach would be to estimate a hybrid discrete choice model.

Practical implications — Realizing the real importance of personal psychological factors on mode choice is a key issue when intending to implement mobility and travel demand management strategies. The success of these strategies strongly relies on people's change of behaviour, which does not depend only on instrumental and socio-demographic factors, such as cost, time and income, but also on these very inner personal aspects.

Originality/value — Capture psychological factors through a comprehensive survey, which rests on a psychological framework and considers simultaneously attitudinal, affective and habitual personal factors, as well as instrumental and socio-demographic information. Make a comparison among cities belonging to different countries regarding the role of these factors, cities with a different cultural and social background.

Focusing on the conditional cash transfers (CCTs) first created and implemented in Brazil and Mexico, this article takes a new look at the factors facilitating the creation of these innovative policies. In order to shed light on the continuous struggles that are faced when pioneering, formulating and adopting these anti-poverty policies, the authors analyze three types of ambiguities: axiological, partisan and electoral.

Based on a gradual institutional change approach within the advocacy coalition framework, the authors conduct a qualitative analysis of semi-structured interviews, official public administration archives and newspapers.

This article demonstrates that advocacy coalitions (for human capital, basic income and food security) and the quest for electoral gains are viable contexts for exploring the complex processes involved in setting up CCTs, of which Brazil's Bolsa-Família and Mexico's Progresa-Oportunidades-Prospera (POP) provide emblematic examples.

The findings contribute to comparative social policy research and institutional change analysis. The coalitions and ambiguous consensuses studied here expand the perspectives with a more detailed understanding of the chaotic processes involved in developing social policies.

This chapter provides an overview on the traditions and values of teaching students with traumatic brain injury (TBI). First, we discuss the prevalence, identification, and characteristics associated with TBI and how those characteristics affect learning, behavior, and daily life functioning. Next, we focus on instructional and behavioral interventions used in maintaining the traditions in classrooms for working with students with TBI. Findings from a review of the literature conclude that there are no specific academic curriculums designed specifically for teaching students with TBI; however, direct instruction and strategy instruction have been shown to be effective educational interventions. Current research on students with TBI is predominately being conducted in medical centers and clinics focusing on area of impairments (e.g., memory, attention, processing speed) rather than academic achievement and classroom interventions. Finally, we conclude with a list of accommodations and a discussion of recommendations for future work in teaching students with TBI.

This chapter illuminates the central role of kin networks and the routines they construct to maintain family ties and support young fathers in jail. Recent research demonstrates variation in incarcerated fathers’ contact with children. There is less focus on variation in contact with extended kin networks and how kin networks contribute to father–child contact during an incarceration period. Forty-three incarcerated young fathers (ages 19–26) in three Southern California jails, 79% of whom self-identified as Latino, were interviewed to explore fathers’ descriptions of family contact during jail. Incarcerated young fathers rely on kin networks to coordinate routines for contact during jail, including father–child contact. Father inclusion in family life during jail depends not only on the mother of the child but – perhaps integrally – extended paternal kin. Available paternal kin can facilitate connectedness between children and incarcerated fathers in family contexts of complicated parental circumstances (e.g., parental relationship dissolution). Family members mitigate family challenges to maintain ties despite carceral policies meant to isolate fathers from families and children. A continued focus on kin networks and their role in maintaining family connectedness is crucial to understanding and reducing the collateral consequences to family members and incarcerated persons following release from jail.

Digital documentation techniques of tunneling excavations at archaeological sites are becoming more common. These methods, such as photogrammetry and LiDAR (Light Detection and Ranging), are able to create precise three-dimensional models of excavations to complement traditional forms of documentation with millimeter to centimeter accuracy. However, these techniques require either expensive pieces of equipment or a long processing time that can be prohibitive during short field seasons in remote areas. This article aims to determine the effectiveness of various low-cost sensors and real-time algorithms to create digital scans of archaeological excavations.

The authors used a class of algorithms called SLAM (Simultaneous Localization and Mapping) along with depth-sensing cameras. While these algorithms have largely improved over recent years, the accuracy of the results still depends on the scanning conditions. The authors developed a prototype of a scanning device and collected 3D data at a Maya archaeological site and refined the instrument in a system of natural caves. This article presents an analysis of the resulting 3D models to determine the effectiveness of the various sensors and algorithms employed.

While not as accurate as commercial LiDAR systems, the prototype presented, employing a time-of-flight depth sensor and using a feature-based SLAM algorithm, is a rapid and effective way to document archaeological contexts at a fraction of the cost.

The proposed system is easy to deploy, provides real-time results and would be particularly useful in salvage operations as well as in high-risk areas where cultural heritage is threatened.

This article compares many different low-cost scanning solutions for underground excavations, along with presenting a prototype that can be easily replicated for documentation purposes.

Looks at the problems faced by Mexicans and Mexican Americans in the USA. Considers their place and lack of success within the politics of the country. Compares their pay and union rights, their homes and social lives, their treatment by law enforcement agencies and their schools and culture. Briefly covers some improvements which should be considered.