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With the significant growth of world economy and container transportation, large seaports are under the pressure of higher requirements for handling efficiency and often involved in recurrent congestion. For those large seaports, shuttle vessels are usually run between terminals in order to fulfill container inter-terminal transshipment demand as well as to alleviate seaports' congestion effectively. This paper focuses on planning the shuttle vessel routing and scheduling, in which shuttle vessels connect a main terminal and neighboring terminals for container pickup. Two mixed-integer programming formulations are developed. The first model aims to minimize the total operational cost and the second further takes into account the time window requirement. A two-phase heuristic algorithm is devised to find a near-optimal solution within the short computational time for large-scale problems. According to the computational results, the first model shows high searching efficiency if cargo owners do not have time requirement. The two-phase heuristic algorithm shows both efficiency and effectiveness in searching near-optimal solution of the second model for large-scale instances considering time windows. The routing analysis indicates that terminal operators focus on time or no-load rate, respectively, when the waiting penalty shift from low to high. [ABSTRACT FROM AUTHOR]

As a sustainable transportation alternative, cycling has been developed by many large cities as one essential measure for addressing the "last mile problem" in urban areas with high mobility demand. Developing a safe and friendly lane network for cycling has become an urgent task for governments, especially for many Chinese cities encountering a rapid increase in the use of "dockless" shared bikes, such as Mobike and Ofo. The emergence of such kind of app-driven dockless bike sharing systems results in a fast growth in the cycling mobility demand, and leads to a gap between the growing demand and the existing cycling infrastructure. Therefore, it is imperative to have a good understanding of the cycling travel demand and its infrastructure, and in turn to bridge the supply-demand gap. In this paper, we employ data mining techniques including graphic clustering algorithm, Louvain Method, on a large data set from one of the largest bike sharing companies in China. Then we applied the methodology in two cases in Shanghai, including a campus and an urban area. Typical cycling patterns in the spatial and temporal dimensions are identified automatically by the cluster analysis. It is also found that the construction of the cycling infrastructure is closely related to three factors: non-negligible impact of points of interest (POIs), geographical barriers, and temporal variance of the network. Managerial insights and policy measures are proposed accordingly for improving the cycle lane network. [ABSTRACT FROM AUTHOR]

Nowadays, the significance of developing sustainable transport systems is being reconsidered due to the impact produced by an extensive use of private cars. In this scenario, bicycles are becoming more popular. To encourage cycling, bike-sharing systems have been developed. However, as safety is people's main concern of cycling, bike-sharing systems should be part of an integral project that includes not only docking stations but a dedicated cycle path network connecting them. A two-stage stochastic programming model that maximizes the travel demand covered by the system is developed. Various demand scenarios in terms of different time periods of a day, travel intensities and levels of commuting demand are considered in the model, in order to obtain robust solutions. A real-world case study based on the city of Montevideo in Uruguay is conducted. The obtained solution shows that the model tends to develop bicycle lane network with good connectivity between transit stations and normal stations, and the obtained network possesses good robustness. [ABSTRACT FROM AUTHOR]

With the development of urbanization and the extension of city boundaries, the expansion of rapid transit systems based on the existing lines becomes an essential issue in urban transportation systems. In this study, the network expansion problem is formulated as a bi‐objective programming model to minimize the construction cost and maximize the total travel demand covered by the newly introduced transit lines. To solve the bi‐objective mixed‐integer linear program, an approach called minimum distance to the utopia point is applied. Thus, the specific trade‐off is suggested to the decision makers instead of a series of optimal solutions. A real‐world case study based on the metro network in Wuxi, China, is conducted, and the results demonstrate the effectiveness and efficiency of the proposed model and solution method. It is found that the utopia method can not only provide a reasonable connecting pattern of the network expansion problem but also identify the corridors with high priority under the limited budget condition. [ABSTRACT FROM AUTHOR]

The study was aimed to compare the effects of T-cell suppression mediated by mesenchymal stem cells (MSC) from normal individuals and myelodysplastic syndromes (MDS) patients. MSC were cultured from the bone marrow of 12 healthy volunteers and 12 MDS patients, the morphology, surface markers and expression of several cytokines of MSC from normal individuals and MDS patients were compared, and the effects of T-cell suppression were tested in the following assays: phytohemaglutinin (PHA)-primed cultures, mixed lymphocyte reaction (MLR), cell cycle of T-cell after PHA-primed cultures and apoptosis of T-cell as well. The results showed that the MSC from normal individuals and MDS patients were similar in morphology, proliferation and surface markers. The suppressions of T-cell proliferation induced by PHA and alloantigens mediated by MDS-MSC were significantly lower than that of normal MSC. More T-cells were arrested in G0/G1 phase by normal MSC, while the effects were deficient by MDS-MSC. The suppression of T-cell activation mediated by MDS-MSC was also lower than that of normal MSC, but suppression effect on T-cell apoptosis increased. The cytokines TGF-beta1, 3, FasL expressed by MDS-MSC were reduced as compared with normal MSC, but TGF-beta2 expression increased in MDS-MSC. It is concluded that although the morphology, proliferation and cell surface markers of MDS-MSC are normal, the T-cell suppression mediated by MDS-MSC is deficient as compared with normal controls. Whether these abnormalities are relevant to the pathogenesis of aplastic anemia remains to be determined.

Objective: To investigate the effect of mesenchymal stem cell (MSC) on naive T cell and to explore its mechanism of immunoregulation., Methods: After culturing for 3 passages, MSC was incubated with naive T cells differentiated from cord blood CD34(+) cells in vitro. Variance of cytokine produced by naive T cell in culture supernatant was analyzed by enzyme-linked immunoassays., Results: On the 7th day of co-culture, a mild proliferation of T cells in the co-culture group was observed: (9.15 +/- 0.68) x 10(5)/well in MSCs + naive T cells group versus (4.87 +/- 1.33) x 10(5)/well in naive T cells alone group (P < 0.05). IFN-gamma production was lower in MSCs + naive T cells group than that in naive T cells alone group: (1.147 +/- 0.181) pg/ml versus (4.897 +/- 0.189) pg/ml (P < 0.05), but IL-2 production was higher in the co-culture group: (16.141 +/- 2.729) pg/ml versus (2.551 +/- 0.460) pg/ml (P < 0.05). Neither IL-4 nor IL-10 were detected., Conclusions: MSC have allogeneic effect on naive T cell, but may suppress alloreactive T lymphocyte and reduce the incidence of GVHD partly by decreased IFN-gamma production. The result may provide new clues for explaining immunoregulatory mechanism of MSC.

The purpose was to study the effect of mesenchymal stem cell (MSC) on immune function, and to explore the new strategy to prevent graft versus host disease (GVHD) and host versus graft reaction (HVGR) in allogeneic bone marrow transplantation. MSCs from human bone marrow cells were isolated and cultured. The purity of MSCs were identified with the spindle-fibroblastic morphological characterization by microphotography, and the phenotypes were tested by flow cytometry. MSCs were planted in 6-well plates (8 x 10(4)/well for group A, 4 x 10(4)/well for group B and 2 x 10(4)/well for group C), and cocultured for 7 days with T cell isolated from peripheral blood. Peripheral blood T cells non-cocultured with MSC acted as the control group. CD3, CD4, CD8, and CD25 expressed on T cells were analyzed by flow cytometry after coculture with MSCs for 0, 24, 72 hours and 7 days respectively. The results showed that CD4(+)CD25(+) T cells and CD8(+) T cells of allogeneic T lymphocytes cocultured with bone marrow MSCs (group A and group B) increased obviously as compared with control group (T lymphocytes uncocultured with MSCs), and there were no difference between groups A and B. CD3, CD4, CD8 and CD25 expressed on T cells had no significant difference between experimental groups and control group. The result suggested that CD4(+)CD25(+)-regulatory T cells and CD8(+) T cells were increased apparently when cocultured with allogeneic MSCs. It is concluded that MSCs pretreatment may be useful in the prevention of GVHD and HVGR in allogeneic bone marrow transplantation and provides a new strategy to induce transplantation tolerance.