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Considering the important realistic benefits of drones combined with trucks for last‐mile parcel deliveries, we define the truck–drone routing problem with time windows (TDRP‐TW). The TDRP‐TW has the characteristics of time windows, synchronization en route, direct delivery, multiple trucks, and multiple drones carried by each truck. Customers covered by truck routes can be used as drone launch/retrieval locations, which are called satellites in this study. The synchronization en route enables drones to launch from trucks to return to paired trucks at nodes other than departure sites if necessary. We present an effective branch‐price‐and‐cut algorithm, in which a concept named candidate forward‐satellite (CFS) is introduced to manage the labeling challenge caused by the synchronization en route. In addition, the branch‐price‐and‐cut algorithm is combined with an adaptive large neighborhood search to obtain approximation solutions for large‐scale instances. In the computational experiments, instances with up to 50 customers are solved to optimality, and approximation solutions of large‐scale instances with 100 customers are presented. [ABSTRACT FROM AUTHOR]

Background: Metabolic syndrome (MetS) is characterized by a cluster of signs of metabolic disturbance and has caused a huge burden on the health system. The study aims to explore the prevalence and characteristics of MetS defined by different criteria in the Chinese population.Methods: Using the data of the China Hypertension Survey (CHS), a nationally representative cross-sectional study from October 2012 to December 2015, a total of 28,717 participants aged 35 years and above were included in the analysis. The MetS definitions of the International Diabetes Federation (IDF), the updated US National Cholesterol Education Program Adult Treatment Panel III (the revised ATP III), and the Joint Committee for Developing Chinese Guidelines (JCDCG) on Prevention and Treatment of Dyslipidemia in Adults were used. Multivariable logistic regression was used to identify factors associated with MetS.Results: The prevalence of MetS diagnosed according to the definitions of IDF, the revised ATP III, and JCCDS was 26.4%, 32.3%, and 21.5%, respectively. The MetS prevalence in men was lower than in women by IDF definition (22.2% vs. 30.3%) and by the revised ATP III definition (29.2% vs. 35.4%), but the opposite was true by JCDCG (24.4%vs 18.5%) definition. The consistency between the three definitions for men and the revised ATP III definition and IDF definition for women was relatively good, with kappa values ranging from 0.77 to 0.89, but the consistency between the JCDCG definition and IDF definition (kappa = 0.58) and revised ATP III definition (kappa = 0.58) was poor. Multivariable logistic regression showed that although the impact and correlation intensity varied with gender and definition, area, age, education, smoking, alcohol use, and family history of cardiovascular disease were factors related to MetS.Conclusions: The prevalence and characteristics of the MetS vary with the definition used in the Chinese population. The three MetS definitions are more consistent in men but relatively poor in women. On the other hand, even if estimated according to the definition of the lowest prevalence, MetS is common in China. [ABSTRACT FROM AUTHOR]