3D DOPs for Positioning Applications Using Range Measurements

For terrestrial positioning, some applications require three dimensional coordinates. The Dilution of precisions (DOPs) for position systems using range measurement are reviewed and the average values of DOPs for different deployments of base station geometries are examined. It is shown that to obtain the lowest DOPs, the base stations for different types of positioning systems need to be deployed differently. Changing the N-sided regular polygon to an (N - 1)-sided polygon with one base station in the centre of the polygon can decrease the value of DOP in general for a pseudorange time of arrival (TOA) system but not for an absolute range TOA system. The height of the base station in the centre can also change the DOP significantly. The finding can be used to optimize the deployment of the base stations for range measurement positioning systems.

Enhancement of T cell infiltration via tumor-targeted Th9 cell delivery improves the efficacy of antitumor immunotherapy of solid tumors

Insufficient infiltration of T cells severely compromises the antitumor efficacy of adoptive cell therapy(ACT)against solid tumors.Here,we present a facile immune cell surface engineering strategy aiming to substantially enhance the anti-tumor efficacy of Th9-mediated ACT by rapidly identifying tumor-specific binding ligands and improving the infiltration of infused cells into solid tumors.Non-genetic decoration of Th9 cells with tumor-targeting peptide screened from phage display not only allowed precise targeted ACT against highly heterogeneous solid tumors but also substantially enhanced infiltration of CD8+T cells,which led to improved antitumor outcomes.Mechanistically,infusion of Th9 cells modified with tumor-specific binding ligands facilitated the enhanced distribution of tumor-killing cells and remodeled the immunosuppressive microenvironment of solid tumors via IL-9 mediated immunomodulation.Overall,we presented a simple,cost-effective,and cell-friendly strategy to enhance the efficacy of ACT against solid tumors with the potential to complement the current ACT.

A new modeling approach for stress-strain relationship taking into account strain hardening and stored energy by compacted graphite iron evolution

Compacted graphite iron(CGI)is considered to be an ideal diesel engine material with excellent physical and mechanical properties,which meet the requirements of energy conservation and emission reduction.However,knowledge of the microstructure evolution of CGI and its impact on flow stress remains limited.In this study,a new modeling approach for the stress–strain relationship is proposed by considering the strain hardening effect and stored energy caused by the microstructure evolution of CGI.The effects of strain,strain rate,and deformation temperature on the microstructure of CGI during compression deformation are examined,including the evolution of graphite morphology and the microstructure of the pearlite matrix.The roundness and fractal dimension of graphite particles under different deformation conditions are measured.Combined with finite element simulation models,the influence of graphite particles on the flow stress of CGI is determined.The distributions of grain boundary and geometrically necessary dislocations(GNDs)density in the pearlite matrix of CGI under different strains,strain rates,and deformation temperatures are analyzed by electron backscatter diffraction technology,and the stored energy under each deformation condition is calculated.Results show that the proportion and amount of low-angle grain boundaries and the average GNDs density increase with the increase of strain and strain rate and decreased first and then increased with an increase in deformation temperature.The increase in strain and strain rate and the decrease in deformation temperature contribute to the accumulation of stored energy,which show similar variation trends to those of GNDs density.The parameters in the stress–strain relationship model are solved according to the stored energy under different deformation conditions.The consistency between the predicted results from the proposed stress–strain relationship and the experimental results shows that the evolution of stored energy can accurately predict the stress–strain relationship of CGI.

A trilogy antimicrobial strategy for multiple infections of orthopedic implants throughout their life cycle

Bacteria-associated infection represents one of the major threats for orthopedic implants failure during their life cycles.However,ordinary antimicrobial treatments usually failed to combat multiple waves of infections during arthroplasty and prosthesis revisions etc.As these incidents could easily introduce new microbial pathogens in/onto the implants.Herein,we demonstrate that an antimicrobial trilogy strategy incorporating a sophisticated multilayered coating system leveraging multiple ion exchange mechanisms and fine nanotopography tuning,could effectively eradicate bacterial infection at various stages of implantation.Early stage bacteriostatic effect was realized via nano-topological structure of top mineral coating.Antibacterial effect at intermediate stage was mediated by sustained release of zinc ions from doped CaP coating.Strong antibacterial potency was validated at 4 weeks post implantation via an implanted model in vivo.Finally,the underlying zinc titanate fiber network enabled a long-term contact and release effect of residual zinc,which maintained a strong antibacterial ability against both Staphylococcus aureus and Escherichia coli even after the removal of top layer coating.Moreover,sustained release of Sr2+and Zn2+during CaP coating degradation substantially promoted implant osseointegration even under an infectious environment by showing more peri-implant new bone formation and substantially improved bone-implant bonding strength.