目的探讨超声高精细血流成像(fine-flow imaging,FFI)技术联合超声弹性成像技术对于脑卒中患者颈动脉斑块稳定性的诊断价值。方法以缺血性脑卒中患者200例作为观察组,有颈动脉斑块患者200例作为对照组。常规灰阶超声观察所有患者颈动脉...目的探讨超声高精细血流成像(fine-flow imaging,FFI)技术联合超声弹性成像技术对于脑卒中患者颈动脉斑块稳定性的诊断价值。方法以缺血性脑卒中患者200例作为观察组,有颈动脉斑块患者200例作为对照组。常规灰阶超声观察所有患者颈动脉斑块特征。采用超声FFI技术检测颈动脉斑块内新生血管情况,进行血流分级,弹性成像技术测量斑块弹性参数。分析比较2组颈动脉斑块特点与缺血性脑卒中相关性。Logistic回归分析研究相关指标与缺血性脑卒中相关性,为患者早期预防提供诊断依据。绘制受试者工作特征(receiver operating characteristic,ROC)曲线分析超声FFI联合弹性成像技术预测缺血性脑卒中发生的临床价值。结果观察组和对照组在年龄、糖尿病史、心血管病史、吸烟史、体重指数(body mass index,BMI)、三酰甘油、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、肌酐、不稳定斑块方面的比较差异有统计学意义(P<0.05)。利用超声弹性成像技术测得观察组B/A比值、组织弹性评分低于对照组(P<0.05)。不稳定斑块组B/A值和组织弹性评分低于稳定斑块组(P<0.05)。观察组和对照组的斑块内新生血管分级比较差异有统计学意义(P<0.05),不稳定斑块组和稳定斑块组的斑块内新生血管分级比较差异有统计学意义(P<0.05)。B/A值(r=0.791,P<0.001)、弹性评分(r=0.773,P<0.001)与斑块稳定性呈正相关。斑块内新生血管分级(r=-0.270,P<0.001)与斑块的稳定性呈负相关。新生血管分级曲线下面积(area under curve,AUC)为0.674,敏感度为51.6%,特异度为75.9%;B/A值AUC为0.822,敏感度为77.4%,特异度为86.2%。两者联合后AUC为0.864,敏感度为80.6%,特异度为86.2%。结论超声高精细血流技术联合弹性成像技术通过评估斑块的稳定性可用于早期预测缺血性脑卒中发生风险,为临床医生早期采取干预措施提供诊断依据,减少缺血性脑卒中发生率。展开更多
Weak measurement amplification,which is considered as a very promising scheme in precision measurement,has been applied to various small physical quantities estimations.Since many physical quantities can be converted ...Weak measurement amplification,which is considered as a very promising scheme in precision measurement,has been applied to various small physical quantities estimations.Since many physical quantities can be converted into phase signals,it is interesting and important to consider measuring small longitudinal phase shifts by using weak measurement.Here,we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation,which is suitable for polarization interferometry.We realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of interference.Besides,we analyze the effect of magnification error which is never considered in the previous works,and find the constraint on the magnification.Our results may find important applications in high-precision measurements,e.g.,gravitational wave detection.展开更多
Research of Maxwell demon and quantum entanglement is important because of its foundational significance in physics and its potential applications in quantum information. Previous studies on the Maxwell demon have pri...Research of Maxwell demon and quantum entanglement is important because of its foundational significance in physics and its potential applications in quantum information. Previous studies on the Maxwell demon have primarily focused on thermodynamics, taking into account quantum correlations. Here we consider from another perspective and ask whether quantum non-locality correlations can be simulated by performing work. The Maxwell demon-assisted Einstein–Podolsky–Rosen(EPR) steering is thus proposed, which implies a new type of loophole. The application of Landauer's erasure principle suggests that the only way to close this loophole during a steering task is by continuously monitoring the heat fluctuation of the local environment by the participant.We construct a quantum circuit model of Maxwell demon-assisted EPR steering, which can be demonstrated by current programmable quantum processors, such as superconducting quantum computers. Based on this quantum circuit model, we obtain a quantitative formula describing the relationship between energy dissipation due to the work of the demon and quantum non-locality correlation. The result is of great physical interest because it provides a new way to explore and understand the relationship between quantum non-locality, information, and thermodynamics.展开更多
文摘目的探讨超声高精细血流成像(fine-flow imaging,FFI)技术联合超声弹性成像技术对于脑卒中患者颈动脉斑块稳定性的诊断价值。方法以缺血性脑卒中患者200例作为观察组,有颈动脉斑块患者200例作为对照组。常规灰阶超声观察所有患者颈动脉斑块特征。采用超声FFI技术检测颈动脉斑块内新生血管情况,进行血流分级,弹性成像技术测量斑块弹性参数。分析比较2组颈动脉斑块特点与缺血性脑卒中相关性。Logistic回归分析研究相关指标与缺血性脑卒中相关性,为患者早期预防提供诊断依据。绘制受试者工作特征(receiver operating characteristic,ROC)曲线分析超声FFI联合弹性成像技术预测缺血性脑卒中发生的临床价值。结果观察组和对照组在年龄、糖尿病史、心血管病史、吸烟史、体重指数(body mass index,BMI)、三酰甘油、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、肌酐、不稳定斑块方面的比较差异有统计学意义(P<0.05)。利用超声弹性成像技术测得观察组B/A比值、组织弹性评分低于对照组(P<0.05)。不稳定斑块组B/A值和组织弹性评分低于稳定斑块组(P<0.05)。观察组和对照组的斑块内新生血管分级比较差异有统计学意义(P<0.05),不稳定斑块组和稳定斑块组的斑块内新生血管分级比较差异有统计学意义(P<0.05)。B/A值(r=0.791,P<0.001)、弹性评分(r=0.773,P<0.001)与斑块稳定性呈正相关。斑块内新生血管分级(r=-0.270,P<0.001)与斑块的稳定性呈负相关。新生血管分级曲线下面积(area under curve,AUC)为0.674,敏感度为51.6%,特异度为75.9%;B/A值AUC为0.822,敏感度为77.4%,特异度为86.2%。两者联合后AUC为0.864,敏感度为80.6%,特异度为86.2%。结论超声高精细血流技术联合弹性成像技术通过评估斑块的稳定性可用于早期预测缺血性脑卒中发生风险,为临床医生早期采取干预措施提供诊断依据,减少缺血性脑卒中发生率。
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 92065113, 11904357, 62075208, and 12174367)the Innovation Programme for Quantum Science and Technology (Grant No. 2021ZD0301604)+1 种基金the National Key Research and Development Program of China (Grant No. 2021YFE0113100)supported by Beijing Academy of Quantum Information Sciences
文摘Weak measurement amplification,which is considered as a very promising scheme in precision measurement,has been applied to various small physical quantities estimations.Since many physical quantities can be converted into phase signals,it is interesting and important to consider measuring small longitudinal phase shifts by using weak measurement.Here,we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation,which is suitable for polarization interferometry.We realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of interference.Besides,we analyze the effect of magnification error which is never considered in the previous works,and find the constraint on the magnification.Our results may find important applications in high-precision measurements,e.g.,gravitational wave detection.
基金the support from the Natural Science Foundation of China (Grant No. 92365206)the support from the Fundamental Research Funds for the Central Universitiessupported by the National Natural Science Foundation of China (Grant No. 92065113)。
文摘Research of Maxwell demon and quantum entanglement is important because of its foundational significance in physics and its potential applications in quantum information. Previous studies on the Maxwell demon have primarily focused on thermodynamics, taking into account quantum correlations. Here we consider from another perspective and ask whether quantum non-locality correlations can be simulated by performing work. The Maxwell demon-assisted Einstein–Podolsky–Rosen(EPR) steering is thus proposed, which implies a new type of loophole. The application of Landauer's erasure principle suggests that the only way to close this loophole during a steering task is by continuously monitoring the heat fluctuation of the local environment by the participant.We construct a quantum circuit model of Maxwell demon-assisted EPR steering, which can be demonstrated by current programmable quantum processors, such as superconducting quantum computers. Based on this quantum circuit model, we obtain a quantitative formula describing the relationship between energy dissipation due to the work of the demon and quantum non-locality correlation. The result is of great physical interest because it provides a new way to explore and understand the relationship between quantum non-locality, information, and thermodynamics.
