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Production scheduling is a class of widely studied combinatorial optimization problems. Given the complexity of the most addressed production environments several solution procedures have been proposed. In recent years, operational researcher practitioners have been paying attention to solving production scheduling problems using constraint programming, and growing interest in this research domain has been evidenced. The aim of this study is to report a descriptive bibliometric analysis of applications of constraint programming in production scheduling problems. The scope of the study is limited to reviewing 170 scientific papers published between 1992 and 2023 from the Scopus and Web of Science databases. In our proposed research questions, we could address the main topics studied, the most studied performance measures, and the profile of the analyzed documents. Furthermore, we could identify the main gaps and present suggestions for future research.

In this paper, a variant of the open shop scheduling problem is considered in which the intermediate storage is forbidden among two adjacent production stages (zero buffer or machine blocking constraint). The performance measure is to minimise the maximal completion time of the jobs (makespan). Since this is an NP-hard problem, a two-stage constraint programming approach is proposed as a new exact method. Computational experiments were carried out on 222 literature problem instances in order to test the performance of the proposed algorithm. The relative deviation is adopted as the performance criteria. Computational results point to the ability of the proposed method to solve large-sized instances in comparison with the developed mixed-integer linear programming model and a simple constraint programming model, both with user cuts. In all set of instances, the proposed two-stage method performed better than benchmarking methods and integer programming models, with average relative deviation regarding objective values as lower as 12%. In addition, the results point to a competitive efficiency in computational times of the proposed method with less than 200 s in the most instances to obtain the optimal solution, in comparison to competitive metaheuristics from literature of the problem, for the tested test instances. [ABSTRACT FROM AUTHOR]

BACKGROUND: Firefighter health is of utmost importance both to first responders and the individuals they serve daily. The impact of shift schedule on firefighter health remains poorly understood. OBJECTIVE: The purpose of this study was to examine differences in health and performance outcomes in firefighters across two different shift schedules. METHODS: Firefighter (N = 1995) body composition, muscular strength, endurance, flexibility, and cardiorespiratory endurance were assessed and described. A Mann-Whitney U test was conducted to compare differences between shift schedules (48/96 and 4's and 6's). RESULTS: There was a statistically significant difference in BMI (U = 70115, z=–1.988, p =.047), BF% (U = 67341, z=–2.779, p =.005), and trunk flexion score (U = 81362, z = 1.979, p =.048) favoring the 48/96 shift schedule. CONCLUSION: Firefighters following a 48/96 shift schedule exhibited improved body composition and fitness performance in comparison to peers who followed a 4's and 6's shift schedule. Findings may guide regional firefighter scheduling to optimize health and performance. [ABSTRACT FROM AUTHOR]

Perceiving that a partner is highly committed tends to benefit close relationships. However, there may be relational drawbacks to perceiving high commitment. In particular, given that high commitment may signal that a partner is unlikely to leave the relationship, perceiving that a partner is highly committed might lead people low in agreeableness to feel comfortable behaving more selfishly toward that partner. One correlational study consisting of a highly diverse sample of individuals (n = 307), one observational study of newlywed couples (n = 202), and one experiment with undergraduate couples (n = 252) examined whether the implications of perceived partner commitment for selfish behaviors depend on agreeableness. Results demonstrated that perceiving high commitment resulted in more selfish behavior among disagreeable participants (Studies 1–3), but less selfish behavior among agreeable participants (Studies 1 and 3). Together, these results suggest that signaling commitment to disagreeable partners may backfire in romantic relationships. [ABSTRACT FROM AUTHOR]

COVID‐19 poses a considerable threat to adolescent mental health. We investigated depression rates in teens from pre to post‐COVID. We also explored if leveraging a growth mindset intervention ("Healthy Minds") could improve adolescent mental health outcomes during the pandemic, especially for adolescents experiencing the most distress. In Study 1, we recruited youth from schools in a rural southern community (N = 239) and used a pre‐post design. In Study 2, we recruited an online sample (N = 833) and used a longitudinal randomized control trial design to test the effectiveness of Healthy Minds. Across both studies, there is evidence of higher rates of depression in youth during COVID‐19, relative to pre‐pandemic numbers. In Study 1, the intervention effectively changed psychological and behavioral processes related to mental health, especially for adolescents experiencing greater COVID‐19 stress. However, in Study 2, the intervention failed to impact depression rates or symptoms at follow‐up. [ABSTRACT FROM AUTHOR]