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A significant portion of air pollutions in a city comes from road transport. Shorter travelling distance and less fuel consumption would logically lead to lower emissions of greenhouse gases or particulate matters, thus relieve environmental burdens. In this regard, an appropriate selection of the logistic sequence may contribute significantly to the environment. The logistic sequence for pickup and delivery services are often determined based on decision makers' experience and intuitive judgements. While life cycle assessment (LCA), a well-versed approach, can be used for quantifying the environmental loads, it is often regarded as not suitable for making routine decisions because it takes significant time and resources for data collection as well as expert knowledge for result interpretation. Additionally, the results of LCA studies focus mainly on the environmental perspective and that other decision criteria cannot be taken into account in a single evaluation process. This paper attempts to develop a practical and objective tool, by combining a simplified LCA with the ant colony optimization algorithm, that supports evaluating several decision criteria simultaneously and determining the optimal or near optimal sequence for vehicle routing on pickup and delivery activities. This fit-for-purpose approach enables decision makers to pay attention to environmental impacts during the determination of the travelling sequences. The proposed approach has been successfully performed to identify the optimal solution through benchmarking against other possible sequences, with the aim to reducing environmental impact while balancing other decision criteria. [ABSTRACT FROM AUTHOR]

Due to the stringent environmental regulatory requirements being imposed by cross-national bodies in recent years, manufacturers have to minimize the environmental impact of their products. Among those environmental impact evaluation tools available, Life Cycle Assessment (LCA) is often employed to quantify the product's environmental impact throughout its entire life cycle. However, owing to the requirements of expert knowledge in environmental science and vast effort for data collection in carrying out LCA, as well as the common absence of complete product information during product development processes, there is a need to develop a more suitable tool for product designers. An evidential reasoning-based approach, which aims at providing a fast-track method to perform design alternative evaluations for non-LCA experts, is therefore introduced as a new initiative to deal with the incomplete or uncertain information. The proposed approach also enables decision makers to quantitatively assess the life cycle phases and design alternatives by comparing their potential environmental impacts, thus effectively and efficiently facilitates the identification of greener designs. A case application is carried out to demonstrate the applicability of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: Background: We have previously reported the successful induction of renal allograft tolerance in non-human primates using a nonmyeloablative conditioning regimen to produce a mixed-chimeric state in the recipient. In the present study, we applied this same technique to lung allotransplantation in cynomolgus monkeys. Methods: Nine pairs of fully major histocompatibility complex (MHC)-mismatched cynomolgus monkeys were used. The conditioning regimen consisted of total body irradiation, thymic irradiation, and antithymocyte globulin. The recipients underwent lung and bone marrow transplantation, followed by anti-CD154 monoclonal antibody (mAb), and a 1-month course of cyclosporine. The regimen included anti-CD8 mAb in the last 5 recipients and α 1-antitripsin in the last 3 recipients. The results were compared with 8 recipients that received kidney allografts using the same regimen. Results: Transient chimerism developed in all lung recipients, as was previously seen in the kidney recipients. Nonetheless, the lung recipients rejected their allografts significant earlier than the kidney recipients (P < .01). Conclusions: Despite the successful induction of mixed chimerism in recipients of fully MHC-mismatched lung allografts, we have not observed long-term graft survival, as has been seen in an analogous kidney model. Strategies to overcome this problem include organ-specific modifications of the transplant regimen. [Copyright &y& Elsevier]

This paper extends the use of the skew boundary condition in two- and three-dimensional (3D) finite element analysis for both structural and geotechnical applications when the need of the freedom directions at the interface nodes is different from the global Cartesian directions. For instance, jack-up structures have three conical-shaped footings, whose freedom directions at the interface nodes are not suitable for Cartesian directions. In addition, there is no axisymmetric movement of the soil as the load is applied to the jack-up's hull. Thus, a more reliable solution of jack-up-soil interaction should be analyzed in a full 3D version. This paper develops a simple 3D interface model for soil-structure interaction that uses skew boundary conditions and incorporates the visco-plastic strain method into the finite element program. The work was validated by computing bearing capacity factors of conical footings with different scenarios, such as plane strain, axisymmetric and 3D analysis. The results of the present analysis are in good agreement with the existing solutions. The fields of the displacement vector and failure patterns at the collapse state are demonstrated and discussed for each apex angle, and the influence of the conical angle on the bearing capacity factor (N c) is also examined. [ABSTRACT FROM AUTHOR]

Abstract: Considerable evidence suggests that indirect recognition of MHC allopeptides plays an important role in solid-organ rejection. Here, we examine whether immunization with class I or class II allopeptides accelerates rejection in a fully MHC-mismatched lung transplant model in miniature swine. Methods: Recipients were immunized with either donor-derived class I or class II peptides. Sensitization to the peptides was confirmed by DTH testing and in vitro proliferation assays. Nonimmunized control (n = 6), class I peptide-immunized (n = 3), and class II peptide-immunized (n = 3) swine were transplanted with fully mismatched lungs using only a 12-day course of tacrolimus. Results: One control animal rejected its graft on postoperative day 103, while the others maintained their grafts for over 1 year. In the class I peptide-immunized group, two recipients rejected their grafts (days 14 and 52). The third animal has not rejected the graft (day 120, experiment is ongoing). In contrast, in the class II-peptide immunized group, only one animal rejected its graft on day 52, while the others maintained their grafts over 1 year. Both anti-donor IgM and IgG antibodies were detectable in all acute rejectors, although no alloantibody was detectable in long-term acceptors. Regardless of the fate of the graft, all animals have maintained their proliferative responses to the peptides. However, only acceptors maintained donor-specific hyporesponsiveness in cell-mediated lymphocytotoxity and mixed lymphocyte reaction assays. Conclusions: Pretransplant sensitization of lung allograft recipients to donor allopeptides accelerates graft rejection. This appears particularly true for class I-derived allopeptides, suggesting that class II molecules may be less antigenic when presented indirectly. [Copyright &y& Elsevier]

Abstract: We have previously reported that tolerance to class I disparate lung allografts in miniature swine could be induced using an intensive 12-day course of tacrolimus and that pretransplant sensitization with immunogenic MHC class I allopeptides failed to block the induction of tolerance. We also have previously reported the importance of the presence of the thymus in the induction of tolerance to isolated heart, kidney, and combined heart-kidney transplants. In this study, we examined the impact of thymectomy on tolerance induction in lung transplantation. Methods: Orthotopic left lung transplantation was performed using MHC class I-disparate donors. The recipients received a 12-day course of high-dose tacrolimus (n = 6). Total thymectomies were performed in three of the swine 21 days prior to transplantation. Lung grafts were monitored by chest radiography and serial open lung biopsy. Results: All euthymic recipients maintained their grafts for over 1 year. None of the thymectomized recipients has experienced graft loss in the 6 to 10 months following transplantation. Although isolated lesions of obliterative bronchiolitis were occasionally seen in one thymectomized animal on biopsy, donor-specific unresponsiveness has been observed on assays of cell-mediated lymphocytotoxicity in all recipients. Moreover, co-culture assays have shown that recipient lymphocytes can strongly inhibit the normally robust response of naïve recipient-matched lymphocytes to donor antigen. This inhibition was not seen when using stimulators primed with third-party antigens against appropriate targets. Conclusions: These data suggest that thymus-independent peripheral regulatory mechanisms may be sufficient to induce and maintain long-term acceptance of the lung allografts. [Copyright &y& Elsevier]

Abstract: In this work, we report a non-destructive approach, which is based on the spectroscopic ellipsometry (SE) and a multi-layer model, to calculate the depth profiling of the dielectric functions of SiO2 films containing Si nanocrystals (nc-Si) synthesized by ion beam technique. Each sub-layer of SiO2 film containing nc-Si is represented by Maxwell-Garnett effective medium approximation (EMA). Then the nc-Si dielectric functions are extracted from the best fittings of SE results. Finally, the dielectric functions of each sub-layer of SiO2 containing nc-Si are calculated with Maxwell-Garnett EMA using the previously extracted information of nc-Si, and thus the depth profile of dielectric functions for the SiO2 thin film containing the nc-Si is obtained. [Copyright &y& Elsevier]

We have examined the titled reaction near its threshold using the pulsed field ionization photoelectron–photoion coincidence method. The measured 0 K threshold (18.220±0.002 eV) has made possible the determination of more precise values for the 0 K bond dissociation energies for D–OD+ (5.584±0.002 eV) and D–OD (5.191±0.002 eV) and the 0 K heats of formation (ΔH0f0''s) for OD+ (308.83±0.05 kcal/mol) and OD (8.38±0.05 kcal/mol). We found that the available energetic data for the OD/OD+ and D2O/D2O+ system are in excellent agreement with those for the OH/OH+ and H2O/H2O+ system after taking into account the zero-point vibration energies of these species. [Copyright &y& Elsevier]