Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any pos...Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any post-processing and conditioning,this QRNG can output raw sequences at a rate of 100 Mbps.Remarkably,the statistical min-entropy of the 8,000,000 bits sequence reaches 0.9944 bits/bit,and the min-entropy validated by NIST SP 800-90B reaches 0.9872 bits/bit.This metric is currently the highest value we have investigated for QRNG raw sequences.Moreover,this QRNG can continuously and stably output raw sequences with high randomness over extended periods.The system produced a continuous output of 1,174 Gbits raw sequence for a duration of 11,744 s,with every 8 Mbits forming a unit to obtain a statistical min-entropy distribution with an average value of 0.9892 bits/bit.The statistical min-entropy of all data(1,174 Gbits)achieves the value of0.9951 bits/bit.This QRNG can produce high-quality raw sequences with good randomness and stability.It has the potential to meet the high demand in cryptography for random numbers with high quality.展开更多
Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections...Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.展开更多
目的探讨中心性肥胖与肝癌的关系。方法腰围、经BMI矫正的腰围、臀围、经BMI校正的臀围、腰臀比和经BMI校正的腰臀比相关的全基因组关联分析(genome wide association study,GWAS)数据来自欧洲一个包含224459个样本的大型数据库。内脏...目的探讨中心性肥胖与肝癌的关系。方法腰围、经BMI矫正的腰围、臀围、经BMI校正的臀围、腰臀比和经BMI校正的腰臀比相关的全基因组关联分析(genome wide association study,GWAS)数据来自欧洲一个包含224459个样本的大型数据库。内脏脂肪体积数据集来自欧洲数据库,包括32860名欧洲受试者的9275407个单核苷酸多态性(single nucleotide polymorphism,SNP)位点信息。肝癌的数据集来自英国生物银行数据库,包括372184名欧洲受试者的汇总数据。对获得的数据集进行两样本孟德尔随机化研究。结果逆方差加权法(IVW)分析结果显示,经BMI矫正的腰围会增加肝癌发生风险(OR=1.001,95%CI:1.000~1.001,P=0.024),且被加权中位数(WM)分析(OR=1.001,95%CI:1.000~1.002,P=0.020)证实,但在MR-Egger回归(OR=1.002,95%CI:0.999~1.004,P=0.135)中未被证实。其他中心性肥胖指标与肝癌无关。结论不同中心性肥胖指标与肝癌的相关性存在差异。经BMI矫正的腰围可能会导致肝癌发生,表明在相对较瘦的人群中,中心性肥胖与肝癌发生相关,且可能存在因果关系。展开更多
目的系统评价坤宝丸治疗更年期综合征的有效性和安全性。方法采用计算机检索PubMed,EMbase,The Cochrane Library,Web of Science及中国知网(CNKI)、万方(WanFang)、维普(VIP)数据库自建库起至2022年12月的相关文献。由2位评价员独立筛...目的系统评价坤宝丸治疗更年期综合征的有效性和安全性。方法采用计算机检索PubMed,EMbase,The Cochrane Library,Web of Science及中国知网(CNKI)、万方(WanFang)、维普(VIP)数据库自建库起至2022年12月的相关文献。由2位评价员独立筛选文献、提取资料并评价纳入研究的偏倚风险,采用RevMan 5.3软件对纳入研究进行Meta分析。结果共纳入13项研究,涉及1590例更年期综合征患者,其中观察组803例,对照组787例。按对照组的用药种类进行亚组分析,坤宝丸单用组的临床疗效显著高于氟桂利嗪+谷维素+维生素B1组[RR=1.75,95%CI(1.38,2.22),P<0.00001],坤宝丸联用组临床疗效显著高于戊酸雌二醇+甲羟孕酮组[RR=1.18,95%CI(1.03,1.34),P=0.01]和刺五加组[RR=1.20,95%CI(1.08,1.33),P=0.0007];坤宝丸单用组对更年期临床症状调查表(Kupperman)评分显著低于替勃龙组[MD=-6.00,95%CI(-7.72,-4.28),P<0.00001];坤宝丸联用组卵泡刺激素(FSH)显著低于刺五加组[MD=-25.70,95%CI(-33.22,-18.18),P<0.00001];坤宝丸联用组促黄体素(LH)显著低于刺五加组[MD=-11.20,95%CI(-12.05,-10.35),P<0.00001];坤宝丸单用组雌二醇(E2)显著高于替勃龙组[MD=-7.00,95%CI(-11.44,-2.56),P=0.002]。药品不良反应主要为腹胀、便秘、头晕、阴道出血、体质量增加等,患者均能耐受。结论坤宝丸对更年期综合征患者的临床疗效、Kupperman评分、激素指标等的改善效果与激素类药物相当,甚至更优。但由于纳入研究的质量不高,尚需更严格、高质量的临床研究进一步证实。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51727805)。
文摘Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any post-processing and conditioning,this QRNG can output raw sequences at a rate of 100 Mbps.Remarkably,the statistical min-entropy of the 8,000,000 bits sequence reaches 0.9944 bits/bit,and the min-entropy validated by NIST SP 800-90B reaches 0.9872 bits/bit.This metric is currently the highest value we have investigated for QRNG raw sequences.Moreover,this QRNG can continuously and stably output raw sequences with high randomness over extended periods.The system produced a continuous output of 1,174 Gbits raw sequence for a duration of 11,744 s,with every 8 Mbits forming a unit to obtain a statistical min-entropy distribution with an average value of 0.9892 bits/bit.The statistical min-entropy of all data(1,174 Gbits)achieves the value of0.9951 bits/bit.This QRNG can produce high-quality raw sequences with good randomness and stability.It has the potential to meet the high demand in cryptography for random numbers with high quality.
基金the National Key Research and Development Program of China(Grant No.2020YFA0309702)NSAF(Grant No.U2130205)+3 种基金the National Natural Science Foundation of China(Grant Nos.62101597,61605248,and 61505261)the China Postdoctoral Science Foundation(Grant No.2021M691536)the Natural Science Foundation of Henan(Grant Nos.202300410534 and 202300410532)the Anhui Initiative in Quantum Information Technologies。
文摘Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.