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Honglei Hu,1,2,* Shuting Zheng,1,2,* Meirong Hou,1,2 Kai Zhu,1,2 Chuyao Chen,1 Zede Wu,1,2 Li Qi,3 Yunyan Ren,1 Bin Wu,4 Yikai Xu,1 Chenggong Yan,1,5 Bingxia Zhao2,6 1Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, People’s Republic of China; 2Guangzhou Key Laboratory of Tumor Immunology Research, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, People’s Republic of China; 3Guangdong Provincial Key Laboratory of Medical Image Processing, Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, School of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, People’s Republic of China; 4Institute of Respiratory Diseases, Respiratory Department, The Affiliated Hospital of Guangdong Medical University, Zhanjiang, 524001, People’s Republic of China; 5Guangdong Provincial Key Laboratory of Shock and Microcirculation, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, People’s Republic of China; 6Experimental Education/Administration Center, School of Basic Medical Science, Southern Medical University, Guangzhou, 510515, People’s Republic of China*These authors contributed equally to this workCorrespondence: Bingxia Zhao; Yikai Xu, Tel +86 20 61647272; +86 20 62787333, Email bingxiaz@gmail.com; yikaixu917@gmail.comBackground: Radiotherapy (RT) is clinically well-established cancer treatment. However, radioresistance remains a significant issue associated with failure of RT. Phototherapy-induced radiosensitization has recently attracted attention in translational cancer research.Methods: Cu-Sb-S nanoparticles (NPs) coated with ultra-small Au nanocrystals (Au@Cu-Sb-S) were synthesized and characterized. The biosafety profiles, absorption of near-infrared (NIR) laser and radiation-enhancing effect of the NPs were evaluated. In vitro and in vivo spectral computed tomography (CT) imaging and photoacoustic (PA) imaging were performed in 4T1 breast cancer-bearing mice. The synergetic radio-phototherapy was assessed by in vivo tumor inhibition studies.Results: Au@Cu-Sb-S NPs were prepared by in situ growth of Au NCs on the surface of Cu-Sb-S NPs. The cell viability experiments showed that the combination of Au@Cu-Sb-S+NIR+RT was significantly more cytotoxic to tumor cells than the other treatments at concentrations above 25 ppm Sb. In vitro and in vivo spectral CT imaging demonstrated that the X-ray attenuation ability of Au@Cu-Sb-S NPs was superior to that of the clinically used Iodine, particularly at lower KeV levels. Au@Cu-Sb-S NPs showed a concentration-dependent and remarkable PA signal brightening effect. In vivo tumor inhibition studies showed that the prepared Au@Cu-Sb-S NPs significantly suppressed tumor growth in 4T1 breast cancer-bearing mice treated with NIR laser irradiation and an intermediate X-ray dose (4 Gy).Conclusion: These results indicate that Au@Cu-Sb-S integrated with spectral CT, PA imaging, and phototherapy-enhanced radiosensitization is a promising multifunctional theranostic nanoplatform for clinical applications.Keywords: Au@Cu-Sb-S nanoparticle, phototherapy, radiotherapy, spectral CT, photoacoustic imaging

The mixing of soil and fertilizer is critically important for the deep application of organic fertilizer. The mixing of soil and fertilizer generally needs to be conducted during the transportation process. Here, a screw auger with paddles was used to improve the mixing performance of particles during the transport of materials. The discrete element method (DEM) and experimental measurements were used to characterize the effect of paddle configurations on particle mixing. Four parameters with five levels were used in the simulations. The paddle configurations had a major effect on the mixing performance and granular behavior. The relative standard deviation (RSD) results obtained from the validated DEM models revealed that devices with larger paddle rotational speeds n, sideward angles α, pitch angles β and 3 paddles conferred higher mixing performance. The effect of paddle configurations on the paddle-particle and particle-particle average contact forces was also analyzed. Higher paddle rotational speeds n, sideward angles α and pitch angles β led to larger average normal contact forces, and the effect of the number of paddles N was small. Analysis of the particle velocity distribution of different configurations revealed that an appropriate paddle configuration with better mixing performance improved the particle velocity. The contributions of both convective and diffusive mechanisms on particle motion were studied, and convection was found to be the dominant mechanism. Generally, the results of this study provide a reference for the selection of an appropriate paddle configuration that confers higher mixing performance and lower power consumption.

A scraper is the most commonly used tool for removing soil from ridges used to cold-proof vines grown in northern China. It can have different complex shapes and its structure and working parameters are vital for effectively removal soil and saving energy. In this study, the interaction between the scraper and the soil was simulated using discrete element method (DEM) simulation, and a calibrated DEM model was developed to simulate soil removal of the scraper. The scraper with different profiles (straight-line, arc, and parabola), different entry angle (δ) and different wing opening angle (θ) were simulated and analysed at various forward speeds (v) in DEM model. The draught force and bilateral soil throw width of the scraper were used to evaluate the effect of soil removal. The DEM model was verified by field experiment, and the draught force and bilateral soil throw width in DEM simulation were compared with the field experiment and the relative errors were 5.97% and 2.88%, respectively. This shows that the DEM model can accurately simulate and optimise the scraper. In order to achieve the best soil removal effect, that is to minimise the draught force and to maximise the bilateral soil throw width, the scraper with arc profile was selected and the optimised values of δ, θ and v were 60°, 86° and 0.6 m s−1, respectively. The corresponding optimal values of draught force and bilateral soil throw width were 58.55 N and 1223 mm, respectively, and based on the optimized parameters, the optimisation results were verified.