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Slot resources are limited and not properly allocated, and the wave-system structures of airlines can organize slot time effectively. The article identifies and evaluates the wave-system structure of Beijing Daxing International Airport and Beijing Capital International Airport. It is found that: the wave-system of Beijing Capital International Airport is more obvious than that of Beijing Daxing International Airport, and the density and amplitude of waves are higher in summer and autumn than in winter and spring; the system waveforms of both Daxing Airport and Capital Airport are in the shape of morning and evening peaks; the indirect connection quality of flights from different departure airports via Capital Airport is higher than that of Daxing Airport; the indirect connections to destination airports via the two airports in Beijing are uneven in spatial distribution. The spatial distribution of indirect connections to destination airports via the two airports is uneven, but the wave-system plays a significant role in connecting small and medium-sized regional airports.

Fuel-use intensity (fuel consumption per value of production) is a fundamental indicator in measuring fuel productivity. During 1997-2008, fuel-use intensity of Changchun's industry has dropped by 64.8%. In order to explain this change, this paper used decomposition analysis to decompose fuel-use intensity into four factors, i. e. recycling, technical efficiency, industrial structure and importing tendency. Then, the contribution rate of each factor to the drop of fuel-use intensity was computed with complete decomposition formula. It is found that industrial structure variation contributed most to the fall of fuel-use intensity, followed by technological progress; while importing tendency made a negative function and recycling is of little help to the decline of fuel-use intensity. Industrial structure variation has reduced fuel-use intensity before 2003 while increased it after 2003. Technological factor functioned steadily and has reduced fuel-use intensity by a large amount after 2005. [ABSTRACT FROM AUTHOR]

Cross-presentation is the key process in stimulation of cytotoxic T lymphocyte (CTL) immune response in eliminating many infectious diseases and tumors. Previous studies have shown that surface modification of poly( D,L-lactic- co-glycolic acid) (PLGA) particles with polycations enhanced their adjuvant ability resulting in a strong antibody response to the encapsulated antigen. However, the in vitro cross-presentation by protamine-coated PLGA nanoparticles (NPs) has not been addressed yet. In this study, a model antigen ovalbumin (OVA) was encapsulated into PLGA nanoparticles, with (OVA-NPs/protamine) or without protamine coating (OVA-NPs). These nanoparticles were then used to stimulate murine bone marrow-derived dendritic cells (BMDCs). Flow cytometry analysis revealed an increase in endocytosis of protamine-coated PLGA nanoparticles by BMDCs at 37°C. Compared with OVA-NPs-treated BMDCs, stimulation with OVA-NPs/protamine led to significantly upregulation of CD80, CD86, and CD83, increased secretion of IL-12p70, and decreased production of IL-4 by BMDCs. Furthermore, OVA-NPs/protamine-treated BMDCs also showed an enhanced cross-presentation to B3Z T cell hybridoma in vitro. Transmission electron microscopy (TEM) study showed that protamine-coated PLGA nanoparticles escaped from lysosomes through the interaction with lysosomal membrane. These results demonstrated that protamine-coated PLGA nanoparticles could enhance the cross-presentation of encapsulated exogenous antigen by facilitating antigen uptake and lysosomal escape, suggesting the feasibility to be a potent adjuvant for cellular vaccines. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010. [ABSTRACT FROM AUTHOR]

Cross-presentation is the key process in stimulation of cytotoxic T lymphocyte (CTL) immune response in eliminating many infectious diseases and tumors. Previous studies have shown that surface modification of poly(D,L-lactic-co-glycolic acid) (PLGA) particles with polycations enhanced their adjuvant ability resulting in a strong antibody response to the encapsulated antigen. However, the in vitro cross-presentation by protamine-coated PLGA nanoparticles (NPs) has not been addressed yet. In this study, a model antigen ovalbumin (OVA) was encapsulated into PLGA nanoparticles, with (OVA-NPs/protamine) or without protamine coating (OVA-NPs). These nanoparticles were then used to stimulate murine bone marrow-derived dendritic cells (BMDCs). Flow cytometry analysis revealed an increase in endocytosis of protamine-coated PLGA nanoparticles by BMDCs at 37°C. Compared with OVA-NPs-treated BMDCs, stimulation with OVA-NPs/protamine led to significantly upregulation of CD80, CD86, and CD83, increased secretion of IL-12p70, and decreased production of IL-4 by BMDCs. Furthermore, OVA-NPs/protamine-treated BMDCs also showed an enhanced cross-presentation to B3Z T cell hybridoma in vitro. Transmission electron microscopy (TEM) study showed that protamine-coated PLGA nanoparticles escaped from lysosomes through the interaction with lysosomal membrane. These results demonstrated that protamine-coated PLGA nanoparticles could enhance the cross-presentation of encapsulated exogenous antigen by facilitating antigen uptake and lysosomal escape, suggesting the feasibility to be a potent adjuvant for cellular vaccines., (Copyright © 2010 Wiley Periodicals, Inc.)