In the multi-radar networking system,aiming at the problem of locating long-distance targets synergistically with difficulty and low accuracy,a dual-station joint positioning method based on the target measurement err...In the multi-radar networking system,aiming at the problem of locating long-distance targets synergistically with difficulty and low accuracy,a dual-station joint positioning method based on the target measurement error feature complementarity is proposed.For dual-station joint positioning,by constructing the target positioning error distribution model and using the complementarity of spatial measurement errors of the same long-distance target,the area with high probability of target existence can be obtained.Then,based on the target distance information,the midpoint of the intersection between the target positioning sphere and the positioning tangent plane can be solved to acquire the target's optimal positioning result.The simulation demonstrates that this method greatly improves the positioning accuracy of target in azimuth direction.Compared with the traditional the dynamic weighted fusion(DWF)algorithm and the filter-based dynamic weighted fusion(FBDWF)algorithm,it not only effectively eliminates the influence of systematic error in the azimuth direction,but also has low computational complexity.Furthermore,for the application scenarios of multi-radar collaborative positioning and multi-sensor data compression filtering in centralized information fusion,it is recommended that using radar with higher ranging accuracy and the lengths of baseline between radars are 20–100 km.展开更多
Hepatocellular carcinoma （HCC） is one of the most common and deadly malignancies worldwide. To date, the survival of patients with HCC has not improved because of the insensitivity of HCC to conventional treatments....Hepatocellular carcinoma （HCC） is one of the most common and deadly malignancies worldwide. To date, the survival of patients with HCC has not improved because of the insensitivity of HCC to conventional treatments. Sonodynamic therapy （SDT） is a promising new approach that shows remarkable potential in the treatment of HCC. Here, we designed a simple, biocompatible, and multifunctional nanosystem that combines SDT and chemotherapy to treat HCC. This nanosystem, called HPDF nanoparticles, had a core-shell structure in which hematoporphyrin （HP） was complexed with doxorubicin （DOX） to form the hydrophobic core and the surface was coated with Pluronic F68 to form the hydrophilic shell. In HCC cells, HPDF nanoparticles in combination with ultrasonic irradiation （1.0 MHz, 1.5 W/cm2, 30 s） exhibited potent cytotoxicity, resulting from the synergistic effects of a large amount of reactive oxygen species generated from HP and DOX-induced DNA damage. Notabl~ HPDF nanoparticles in combination with ultrasonic irradiation significantly reversed drug resistance in Nanog-positive cancer stem cells （CSCs） in HCC. In nude mice bearing HCC tumors, HPDF nanoparticles efficiently accumulated in the tumors and reached the maximum levels within 6-8 h, post intravenous injection. HPDF nanoparticles, in combination with ultrasonic irradiation （1.0 MHz, 3 W/cm2, 5 min）, suppressed tumor growth, angiogenesis, and collagen deposition, considerably. In summary, our results show that HPDF nanoparticles can effectively combine SDT and chemotherapy to inhibit HCC growth and progression through multiple mechanisms in both cellular and animal models.展开更多
文摘In the multi-radar networking system,aiming at the problem of locating long-distance targets synergistically with difficulty and low accuracy,a dual-station joint positioning method based on the target measurement error feature complementarity is proposed.For dual-station joint positioning,by constructing the target positioning error distribution model and using the complementarity of spatial measurement errors of the same long-distance target,the area with high probability of target existence can be obtained.Then,based on the target distance information,the midpoint of the intersection between the target positioning sphere and the positioning tangent plane can be solved to acquire the target's optimal positioning result.The simulation demonstrates that this method greatly improves the positioning accuracy of target in azimuth direction.Compared with the traditional the dynamic weighted fusion(DWF)algorithm and the filter-based dynamic weighted fusion(FBDWF)algorithm,it not only effectively eliminates the influence of systematic error in the azimuth direction,but also has low computational complexity.Furthermore,for the application scenarios of multi-radar collaborative positioning and multi-sensor data compression filtering in centralized information fusion,it is recommended that using radar with higher ranging accuracy and the lengths of baseline between radars are 20–100 km.
基金This research was supported by the National Natural Science Foundation of China （Nos. 81573005, 81371671, and 81472683） and the National High-tech R＆D Program of China （863 Program, No. 2015AA020403）. The authors thank Prof. C. Qian （Third Military Medical University, Chongqing, China） for providing NanogPos CSCs and NanogNeg cells.
文摘Hepatocellular carcinoma （HCC） is one of the most common and deadly malignancies worldwide. To date, the survival of patients with HCC has not improved because of the insensitivity of HCC to conventional treatments. Sonodynamic therapy （SDT） is a promising new approach that shows remarkable potential in the treatment of HCC. Here, we designed a simple, biocompatible, and multifunctional nanosystem that combines SDT and chemotherapy to treat HCC. This nanosystem, called HPDF nanoparticles, had a core-shell structure in which hematoporphyrin （HP） was complexed with doxorubicin （DOX） to form the hydrophobic core and the surface was coated with Pluronic F68 to form the hydrophilic shell. In HCC cells, HPDF nanoparticles in combination with ultrasonic irradiation （1.0 MHz, 1.5 W/cm2, 30 s） exhibited potent cytotoxicity, resulting from the synergistic effects of a large amount of reactive oxygen species generated from HP and DOX-induced DNA damage. Notabl~ HPDF nanoparticles in combination with ultrasonic irradiation significantly reversed drug resistance in Nanog-positive cancer stem cells （CSCs） in HCC. In nude mice bearing HCC tumors, HPDF nanoparticles efficiently accumulated in the tumors and reached the maximum levels within 6-8 h, post intravenous injection. HPDF nanoparticles, in combination with ultrasonic irradiation （1.0 MHz, 3 W/cm2, 5 min）, suppressed tumor growth, angiogenesis, and collagen deposition, considerably. In summary, our results show that HPDF nanoparticles can effectively combine SDT and chemotherapy to inhibit HCC growth and progression through multiple mechanisms in both cellular and animal models.
