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Urged by the necessity to establish sustainable supply chains (SCs), this study focuses on exploring the closed-loop inventory routing problem (CIRP) for perishable food packed by multi-type returnable transport items (RTIs). The selling revenue of perishable food is dependent on food's remaining shelf life and the specific type of RTIs used for packaging. RTI selection decisions need to be jointly considered in the CIRP to weigh the potential benefits against associated costs. For this problem, we first develop an integer linear programme (ILP) to maximise the total profit of the holistic SC. Subsequently, we design a tailored kernel search (KS) matheuristic as an efficient solution. A real CIRP with multi-type RTIs for fresh strawberries is used to demonstrate the practicality of the ILP. For this case study, we perform extensive sensitivity analysis of the relevant parameters, extracting valuable managerial insights. Finally, experiments are conducted on 170 randomly generated instances. Computational results show that the proposed KS manages to achieve competitive solutions for instances with up to 10 retailers much more efficiently than CLPEX. For instances with up to 40 retailers, the KS algorithm significantly outperforms CPLEX in terms of solution quality, improving the obtained profit by 80.03% on average under the same computational time. [ABSTRACT FROM AUTHOR]

We investigate a stochastic distributed appointment assignment and scheduling problem, which consists of assigning appointments to distributed service units and determining service sequences at each service unit. In particular, the service time duration and release time uncertainties are well-considered. The solution to this generic problem finds interesting applications in distributed production systems, healthcare systems, and post-disaster operations. We formulate the problem as a two-stage stochastic program to minimise the total transportation cost and expected makespan, idle time or overtime, and apply the sample average approximation method to make the problem tractable. We then develop a stochastic logic-based Benders decomposition method, decomposing the problem into a master problem and a subproblem. The master problem determines the appointment assignment variables, and the subproblem handles the sequence and service start time variables. Benders optimality cuts are generated from the subproblem's solution and added to the master problem. The developed stochastic logic-based method is advantageous since it can manage many scenarios in parallel. We further consider each appointment's due date, minimise the weighted earliness and tardiness, and adjust the developed method to solve this variant. Experiments on random instances demonstrate the excellent performance of the proposed model and methods. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) infection is prevalent and associated with the development of various gastric diseases. On the other hand, inflammatory bowel disease (IBD) is an immune‐related intestinal disorder influenced by factors like gut microbiota imbalance, genetic predisposition, and environmental influences. Despite extensive research on the H. pylori–IBD relationship, a comprehensive bibliometric analysis in this area is lacking. Therefore, this study aims to use bibliometric methods to explore research trends, hotspots, and frontiers in H. pylori and IBD‐related research, offering valuable insights for future research and clinical practice. Methods: We retrieved relevant literature on H. pylori and IBD from the Web of Science Core Collection (WoSCC) and Scopus databases covering 2007 to 2024. We perform a comprehensive analysis within the WoSCC literature. We compare these findings with relevant results from Scopus. Results: Research on H. pylori and IBD has remained prominent in recent years. The United States leads in output, with strong contributions from authors, institutions, and journals. China, despite being a developing country, shows rapid article growth, signaling growing research potential. Key topics include Crohn's disease, gut microbiota, H. pylori infection, and ulcerative colitis. Newer interests include health, cancer prevention, and chronic gastritis. Conclusion: Over the past, research on H. pylori and IBD has primarily centered around epidemiology and clinical studies. The question of whether H. pylori definitively offers protective effects against IBD remains unresolved. Therefore, further investigation could explore the underlying mechanisms of their relationship or initiate long‐term prospective cohort studies to gather more compelling evidence. [ABSTRACT FROM AUTHOR]

This study investigates the unrelated parallel machine scheduling problem with release dates to minimise the makespan. The solution to this problem finds wide applications in manufacturing and logistics systems. Due to the strong NP-hardness of the problem, most researchers develop heuristics, and the largest instances they consider are limited to 400 jobs. To tackle this problem, we develop a novel mixed-integer linear program (MILP) with significantly fewer integer variables than the state-of-the-art ones. The proposed MILP does not rely on a binary sequence variable usually used in the existing models. To deal with large-sized instances, a new three-stage matheuristic algorithm (TSMA) is proposed to obtain scheduling decisions. It uses a dispatching rule to sequentially schedule jobs on machines. Then a reassignment procedure is performed to reduce the makespan. Finally, it employs a re-optimisation procedure based on the proposed MILP to perform job moves and exchanges between two selected machines. We conduct numerical experiments on 1440 instances with up to 3000 jobs and 20 machines. Our results first clearly indicate that the proposed model significantly outperforms existing ones. Moreover, the results on large-sized instances show that the proposed TSMA can obtain high-quality near-optimal solutions in a short computation time. [ABSTRACT FROM AUTHOR]