大规模MIMO系统中存在大量相干信号,简单的去相干处理导致二维波达方向(DOA, Direction of Arrival)估计的精度较低。为此,本文提出一种能够大幅度提高相干信号二维DOA估计性能的模等式约束降维MUSIC算法。该算法将二维DOA估计问题转化...大规模MIMO系统中存在大量相干信号,简单的去相干处理导致二维波达方向(DOA, Direction of Arrival)估计的精度较低。为此,本文提出一种能够大幅度提高相干信号二维DOA估计性能的模等式约束降维MUSIC算法。该算法将二维DOA估计问题转化为优化问题,并采用模等式约束法定义附加条件,对方向矢量施加较强的约束,使优化方程求解更接近最优解。理论分析和仿真实验结果表明,本文提出的去相干DOA算法的可靠性与精度高,满足大规模MIMO系统的DOA估计性能需求,具有较强的可行性和实用性。展开更多
Atherosclerosis(AS)is the leading cause of heart attacks,stroke,and peripheral vascular disease.Berberine(BBR),a botanical medicine,has diversified anti-atherosclerotic effects but with poor absorption.The aim of this...Atherosclerosis(AS)is the leading cause of heart attacks,stroke,and peripheral vascular disease.Berberine(BBR),a botanical medicine,has diversified anti-atherosclerotic effects but with poor absorption.The aim of this study was to develop an effective BBR-entrapped nano-system for treating AS in high-fat diet(HFD)-fed Apoe(-/-)mice,and also explore the possible underlying mechanisms involved.Three D-a-tocopherol polyethylene glycol(PEG)succinate(TPGS)analogues with different PEG chain lengths were synthesized to formulate BBR-entrapped micelles.HFD-fed Apoe(-/-)mice were administered with optimized formula(BBR,100 mg/kg/day)orally for 5 months.The artery plaque onset and related metabolic disorders were evaluated,and the underlying mechanisms were studied.Our data showed that,BT1500M increased BBR deposition in liver and adipose by 107.6%and 172.3%,respectively.In the Apoe(-/-)mice,BT1500M ameliorated HFD-induced hyperlipidemia and lipid accumulation in liver and adipose.BT1500M also suppressed HFD-induced chronic inflammation as evidenced by the reduced liver and adipose levels of interleukin-6(IL-6),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β);and decreased plasma level of TNF-α,IL-6,IL-1β,interferon-γ(IFN-γ),monocyte chemotactic protein(MCP),and macrophage inflammatory factor(MIP).The mechanism study showed that BT1500M changed Ampk and Nf-Kb gene expression,and interrupted a crosstalk process between adipocytes and macrophages.Further investigation proved that BT1500M decreased endothelial lesion and subsequent macrophage activation,cytokines release,as well as cholesteryl ester gathering in the aortic arch,resulting in ameliorated artery plaque build-up.Our results provide a practical strategy for treating AS using a BBR-entrapped nano-system.展开更多
文摘大规模MIMO系统中存在大量相干信号,简单的去相干处理导致二维波达方向(DOA, Direction of Arrival)估计的精度较低。为此,本文提出一种能够大幅度提高相干信号二维DOA估计性能的模等式约束降维MUSIC算法。该算法将二维DOA估计问题转化为优化问题,并采用模等式约束法定义附加条件,对方向矢量施加较强的约束,使优化方程求解更接近最优解。理论分析和仿真实验结果表明,本文提出的去相干DOA算法的可靠性与精度高,满足大规模MIMO系统的DOA估计性能需求,具有较强的可行性和实用性。
基金supported by the CAMS Innovation Fund for Medical Sciences(No.2016-I2M-1-011,China)the National Sciences and Technology Major Project(Nos.2018ZX09711001003-002,2017ZX09101003-003-002 and 2016ZX09101017,China)+1 种基金National Natural Science Foundation of China(No.81621064)National Key R&D Project(No.2019YFC170890,China)
文摘Atherosclerosis(AS)is the leading cause of heart attacks,stroke,and peripheral vascular disease.Berberine(BBR),a botanical medicine,has diversified anti-atherosclerotic effects but with poor absorption.The aim of this study was to develop an effective BBR-entrapped nano-system for treating AS in high-fat diet(HFD)-fed Apoe(-/-)mice,and also explore the possible underlying mechanisms involved.Three D-a-tocopherol polyethylene glycol(PEG)succinate(TPGS)analogues with different PEG chain lengths were synthesized to formulate BBR-entrapped micelles.HFD-fed Apoe(-/-)mice were administered with optimized formula(BBR,100 mg/kg/day)orally for 5 months.The artery plaque onset and related metabolic disorders were evaluated,and the underlying mechanisms were studied.Our data showed that,BT1500M increased BBR deposition in liver and adipose by 107.6%and 172.3%,respectively.In the Apoe(-/-)mice,BT1500M ameliorated HFD-induced hyperlipidemia and lipid accumulation in liver and adipose.BT1500M also suppressed HFD-induced chronic inflammation as evidenced by the reduced liver and adipose levels of interleukin-6(IL-6),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β);and decreased plasma level of TNF-α,IL-6,IL-1β,interferon-γ(IFN-γ),monocyte chemotactic protein(MCP),and macrophage inflammatory factor(MIP).The mechanism study showed that BT1500M changed Ampk and Nf-Kb gene expression,and interrupted a crosstalk process between adipocytes and macrophages.Further investigation proved that BT1500M decreased endothelial lesion and subsequent macrophage activation,cytokines release,as well as cholesteryl ester gathering in the aortic arch,resulting in ameliorated artery plaque build-up.Our results provide a practical strategy for treating AS using a BBR-entrapped nano-system.
