New method for passive radar seeker to antagonize non-coherent radar decoy

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（PRS） to antagonize non-coherent radar decoy.Considering the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is proposed.Because this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated sources.Using this new method,PRS can distinguish radar and non-coherent decoy with good performance.Both the simulation result and the experimental data confirm the performance of the method.

Small molecular decoys in Alzheimer's disease

Recent progress in the treatment of Alzheimer’s disease(AD)using antibodies against amyloid sustains amyloid generation as a key process in AD.Amyloid formation starts with two amyloidbeta(Aβ)molecules interacting(dimer formation)followed by an accelerating build-up of socalled protofibrils,which turn into fibrils,which accumulate in the characteristic plaques.

Optimization of jamming formation of USV offboard active decoy clusters based on an improved PSO algorithm

Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and deployment.To improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is proposed.The formation of the cluster determines the effectiveness of jamming.First,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is proposed.Then,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is designed.Finally,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific scenarios.The results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO algorithm.Compared with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources.

Targeted anti-tumor synergistic effects of Myc decoy oligodeoxynucleotides-loaded selenium nanostructure combined with chemoradiotherapy on LNCaP prostate cancer cells

In the present study,we investigated the synergistic effects of targeted methotrexate-selenium nanostructure containing Myc decoy oligodeoxynucleotides along with X-irradiation exposure as a combination therapy on LNCaP prostate cancer cells.Myc decoy ODNs were designed based on the promoter of Bcl-2 gene and analyzed by molecular docking and molecular dynamics assays.ODNs were loaded on the synthesized Se@BSA@Chi-MTX nanostructure.The physicochemical characteristics of nanostructures were determined by FTIR,DLS,UV-vis,TEM,EDX,in vitro release,and hemolysis tests.Subsequently,the cytotoxicity properties of them with and without X-irradiation were investigated by uptake,MTT,cell cycle,apoptosis,and scratch assays on the LNCaP cell line.The results of DLS and TEM showed negative charge(−9 mV)and nanometer size(40 nm)for Se@BSA@Chi-DEC-MTX NPs,respectively.The results of FTIR,UV-vis,and EDX showed the proper interaction of different parts and the correct synthesis of nanoparticles.The results of hemolysis showed the hemocompatibility of this nanoparticle in concentrations less than 6 mg/mL.The ODNs release from the nanostructures showed a pH-dependent manner,and the release rate was 15%higher in acidic pH.The targeted Se@BSA@Chi-labeled ODN-MTX NPs were efficiently taken up by LNCaP cells by targeting the prostate-specific membrane antigen(PSMA).The significant synergistic effects of nanostructure(containing MTX drug)treatment along with X-irradiation showed cell growth inhibition,apoptosis induction(~57%),cell cycle arrest(G2/M phase),and migration inhibition(up to 90%)compared to the control.The results suggested that the Se@BSA@Chi-DEC-MTX NPs can potentially suppress the cell growth of LNCaP cells.This nanostructure system can be a promising approach for targeted drug delivery and chemoradiotherapy in prostate cancer treatment.

A Simple Method to Derive Minimal Cut Sets for a Non-coherent Fault Tree

Minimal cut sets （or prime implicants： minimal combinations of basic event conditions leading to system failure） are important information for reliability/safety analysis and design. To obtain minimal cut sets for general non-coherent fault trees, including negative basic events or multi-valued basic events, a special procedure such as the consensus rule must be applied to the results obtained by logical operations for coherent fault trees, which will require more steps and time. This paper proposes a simple method for a non-coherent fault tree, whose top event is represented as an AND combination of monotonic sub-trees. A ＂monotonic＂ sub-tree means that it does not have both positive and negative representations for each basic event. It is proven that minimal cut sets can be obtained by a conventional method for coherent fault trees. An illustrative example of a simple event tree analysis shows the detail and characteristics of the proposed method.

Novel non-coherent integration method using binary phase-coded radar signal

The m series with 511 bits is taken as an example being applied in non-coherent integra- tion algorithm. A method to choose the bi-phase code is presented, which is 15 kinds of codes are picked out of 511 kinds of m series to do non-coherent integration. It is indicated that the power in- creasing times of larger target sidelobe is less than the power increasing times of smaller target main- lobe because of the larger target＇ s pseudo-randomness. Smaller target is integrated from larger tar- get sidelobe, which strengthens the detection capability of radar for smaller targets. According to the sidelobes distributing characteristic, a method is presented in this paper to remove the estimated sidelobes mean value for signal detection after non-coherent integration. Simulation results present that the SNR of small target can be improved approximately 6. 5 dB by the proposed method.

Non-coherent sequence detection scheme for satellite-based automatic identification system

The satellite-based automatic identification system (AIS) receiver has to encounter the frequency offset caused by the Doppler effect and the oscillator instability. This paper proposes a non-coherent sequence detection scheme for the satellite-based AIS signal transmitted over the white Gaussian noise channel. Based on the maximum likelihood estimation and a Viterbi decoder, the proposed scheme is capable of tolerating a frequency offset up to 5% of the symbol rate. The complexity of the proposed scheme is reduced by the state-complexity reduction, which is based on per-survivor processing. Simulation results prove that the proposed non-coherent sequence detection scheme has high robustness to frequency offset compared to the relative scheme when messages collision exists.

Effect of weak randomness flaws on security evaluation of practical quantum key distribution with distinguishable decoy states

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.

Improved statistical fluctuation analysis for two decoy-states phase-matching quantum key distribution

Phase-matching quantum key distribution is a promising scheme for remote quantum key distribution,breaking through the traditional linear key-rate bound.In practical applications,finite data size can cause significant system performance to deteriorate when data size is below 1010.In this work,an improved statistical fluctuation analysis method is applied for the first time to two decoy-states phase-matching quantum key distribution,offering a new insight and potential solutions for improving the key generation rate and the maximum transmission distance while maintaining security.Moreover,we also compare the influence of the proposed improved statistical fluctuation analysis method on system performance with those of the Gaussian approximation and Chernoff-Hoeffding boundary methods on system performance.The simulation results show that the proposed scheme significantly improves the key generation rate and maximum transmission distance in comparison with the Chernoff-Hoeffding approach,and approach the results obtained when the Gaussian approximation is employed.At the same time,the proposed scheme retains the same security level as the Chernoff-Hoeffding method,and is even more secure than the Gaussian approximation.

核因子-κB decoy ODN改善肺挫伤兔血清抗炎性因子IL-10、IL-13的表达

目的研究NF-κB双链寡脱氧核苷酸圈套(NF-κBdecoy ODN)对严重胸外伤肺挫伤血清NF-κB、IL-10、IL-13及肺组织NF-κB蛋白表达的影响。方法 40只新西兰白兔随机分为⑴严重胸外伤肺挫伤组(n=12);(2)严重胸外伤肺挫伤NF-κB杂链decoy ODN干预组(n=12);(3)严重胸外伤肺挫伤NF-κB正链decoy ODN治疗组(n=12);(4)对照组:正常无损伤组(n=4)。建立严重胸外伤肺损伤模型,按实验分组分别将合成的正链、杂链NF-κBdecoy ODN经颈内静脉注入,每只实验兔分别注射20μg。于肺挫伤前、挫伤后1、2、3、4h检测血清NF-κB、IL-10、IL-13及肺组织NF-κB蛋白的表达。结果肺挫伤后1h,血清中NF-κB含量升高,4h达高峰。经NF-κB正链decoy ODN治疗2h后,升高的NF-κB开始下降,3h达最低值。IL-10、IL-13的表达在肺挫伤后1h下降,并分别于挫伤后2h、4h降至最低值,经杂链decoyODN治疗后,IL-10、IL-13表达无明显改变,而经NF-κB正链decoy ODN治疗后2h,IL-10的表达明显增高,而IL-13的表达维持于较高水平,与挫伤组、杂链decoy ODN治疗组相比,差异具显著性,P<0.01,经正链decoy ODN治疗后挫伤肺组织NF-κB蛋白表达明显降低,差异具有显著性,P<0.01。结论在严重胸外伤肺挫伤早期给予NF-κB正链decoy ODN治疗,可使血清NF-κB表达减少、抗炎性细胞因子IL-10、IL-13表达升高,NF-κB蛋白表达减少。

NF-κB“decoy”寡核苷酸对LPS诱导巨噬细胞IL-10表达的影响

目的 :探讨NF -κB“decoy”寡核苷酸 (ODNs)对脂多糖 (LPS)诱导小鼠巨噬细胞株J774 .1表达IL - 10的影响。方法 :通过体外细胞培养技术 ,观察转染NF -κB“decoy”ODNs对LPS刺激巨噬细胞产生IL - 10及其表达的影响。结果 :在LPS刺激的巨噬细胞中转染NF -κB“decoy”ODNs对抗炎介质IL - 10的合成表达无影响。结论 :NF-κB“decoy”ODNs不抑制抗炎介质IL - 10的表达 ,可能由于NF -κB在IL - 10转录机制中不占主导地位。

靶向STAT3的decoy核酸抑制膀胱癌细胞生长的实验研究

目的观察特异性靶向STAT3的decoy寡核苷酸（0DNs）对膀胱癌细胞增殖和凋亡的影响，并探讨其作用机理。方法通过体外细胞培养技术，将STAT3 decoy ODNs转染入膀胱癌T24细胞内，台盼蓝排斥试验检测细胞活力，MTT法检测细胞增殖状态，Hoechst33258／PI荧光双染检测细胞凋亡特征，流式细胞仪检测细胞周期和早期凋亡，凝胶阻滞电泳检测STAT3的DNA结合活性，RT-P（、R检测STAT3下游靶基因Cyclin D1和Bcl—xL的mRNA表达水平。结果STAT3 decoy ODNs使膀胱癌细胞生长速度减慢，细胞增殖抑制率达75．0％；使细胞周期阻滞，S期细胞比率明显减少，由29．83％下降至1626％，而G0～G1期细胞比率明显增多，由50．82％上升至71．20％；促进膀胱癌细胞凋亡，细胞早期凋亡率高达50．75％；使STAT3的DNA结合活性下降，并使Cyclin D1、Bcl—xL的mRNA表达水平明显下降。结论STAT3 decoy ODNs可特异性靶向作用于STAT3蛋白，阻断STAT3的过度激活效应，通过下调Cyclin D1和Bel—xL的表达抑制膀胱癌细胞增殖，促进其凋亡。

脂质体介导NF-κB decoy ODN低温缺氧对ECV-304的转染及复氧后对下游粘附分子及趋化因子基因表达的影响

目的探讨在Euro-Collin's(ECs)中,低温(4℃)缺氧条件下脂质体(invivoLiposome)介导NF-κB诱捕物寡核苷酸(NF-κBdecoyODN)对人脐静脉内皮细胞株(ECV-304)的转染效率以及复氧后对其细胞分子表达的影响。方法ECV-304在10%FBS的RPMI1640培养液,37℃、5%CO2条件下培养,生长至单层融合后进行试验。使用前配制Liposome/decoyODN和scrambledODN复合物,Liposome与ODN的+/-电荷比率为2。应用荧光显微镜和流式细胞仪,观察在4℃条件下,ODN浓度1.0μM的ECs缺氧保存6h后ECV-304的平均荧光强度(MFI)和摄取率以及ODN的胞内分布;同时设立裸ODN转染为对照,观察Liposome介导ODN对ECV-304的转染效率。利用RT-PCR方法检测各组ECV-304的ICAM-1、VCAM-1、IL-8、MCP-1以及P-selectin的mRNA表达。结果在ECs中、4℃缺氧保存ECV-3046h后,Liposome介导ODN对ECV-304转染的MFI为1072.71±33.14,是裸ODN转染的91.1倍,细胞对ODN的摄取率为93.06±2.60%,是裸ODN转染的71.5倍。Liposome介导ODN转染的ECV-304,荧光显微镜下可见部分荧光颗粒分布于胞浆,胞核内可见强荧光颗粒;而裸ODN转染的ECV-304,胞浆内偶见少量荧光,胞核内未见荧光颗粒。RT-PCR检测显示Liposome/decoyODN转染ECV-304后,其ICAM-1,VCAM-1,IL-8,MCP-1以及P-selectin的mRNA的?

阳离子脂质体介导NF-κB“decoy”ODNs转染巨噬细胞条件的优化

目的 :观察 NF- κB“decoy”ODNs在阳离子脂质体 lipofectin介导下转染小鼠巨噬细胞 J774 .1的优化参数以及在细胞内的分布。 方法 :改变 ODN与 lipofectin比率、转染时间 ;用流式细胞仪检测细胞内的相对荧光强度和摄取率评价转染效率 ;荧光显微镜观察细胞内荧光分布 ;测定细胞上清乳酸脱氢酶 (L DH)观察细胞损伤情况。 结果 :lipofectin介导转染显著提高 J774 .1细胞对 NF- κB“decoy”ODNs的摄取 ;在 2 4孔培养板中 ,NF- κB“decoy”ODNs与 lipofectin比率 (W/ W)为 1∶ 5、转染 6 h时 ,转染效率最佳而细胞毒性相对较低 ;lipofectin介导转染 6 h后 ,细胞内荧光物质主要聚集于细胞核和部分细胞质中 ,而直接转染时荧光物质多分布于细胞质。结论 :lipofectin可增加 NF-κB“decoy”ODNs的细胞摄入并改变其细胞内分布 ;NF-κB“decoy”ODNs与 lipofectin比率 (W/ W)为 1∶ 5、转染 6 h时可获得最佳转染效率。

NF-κB decoy寡核苷酸联合阿霉素诱导裸鼠肝癌细胞HepG_2凋亡

目的:探讨NF-κB decoy寡核苷酸协同阿霉素对裸鼠肝癌细胞HepG2的作用及机制。方法:接种传代培养的人肝癌细胞HepG2于裸鼠皮下,局部注射NF-κB decoy寡核苷酸和/或阿霉素进行治疗。观测裸鼠瘤体大小变化,计算抑瘤率;HE染色观察肝癌组织结构和细胞形态改变;TUNEL法检测细胞凋亡。结果:NF-κB decoy寡核苷酸联合阿霉素治疗组裸鼠肝癌细胞的生长受到明显抑制,抑瘤率为80.52%;肿瘤重量、体积明显小于单用NF-κBdecoy寡核苷酸、阿霉素治疗组及对照组;联合组癌组织凋亡增加,凋亡指数为(39.8±1.6)%,与其余3组比较差异均有统计学意义(P<0.05)。结论:NF-κB decoy寡核苷酸协同阿霉素能抑制NF-κB活性,促进肝癌细胞凋亡,增加其对化疗药物的敏感性。

CRE-decoy ODN对慢性吗啡诱导SK-N-SH细胞CCK及fosB mRNA表达上调的抑制作用

目的:研究以转录因子cAMP反应元件结合蛋白(CREB)为靶点的CRE -decoyODN对慢性吗啡诱导SK -N -SH细胞胆囊收缩素(CCK)及fosBmRNA表达上调的抑制作用。方法:体外合成含cAMP反应元件CRE序列TGACGTCA的单链寡核苷酸,将自身杂交形成发卡结构。将终浓度为15 0nmol/L的CRE -decoyODN与SK -N-SH细胞孵育1h后,加入终浓度为10 0 μmol/L的吗啡作用4 8h ,随后加入终浓度为10 μmol/L的纳络酮,戒断15min。采用电泳迁移率改变分析(EMSA)检测CRE -decoyODN与CREB结合的序列特异性及其对慢性吗啡诱导的CREB的DNA结合活性升高的影响;细胞掺入的CRE -decoyODN用酚:氯仿法提取,经2 0 %非变性聚丙烯酰胺凝胶电泳及放射自显影检测;采用RT -PCR检测CCK及fosBmRNA表达。结果:慢性吗啡作用及纳络酮急性戒断使SK-N -SH细胞CREB的DNA结合活性、CCK和fosBmRNA表达明显升高,CRE -decoyODN可特异抑制其升高。结论:CRE -decoyODN通过特异抑制慢性吗啡诱导SK -N -SH细胞CREB的DNA结合活性而下调CCK及fosBmRNA表达。

表达microRNA-203tough decoy的慢病毒载体构建及应用

目的建立表达microRNA(miRNA)tough decoy(TuD)的慢病毒载体构建方法,并检测其对细胞内miRNA表达水平及细胞表型的影响。方法在慢病毒表达质粒pSIH1-H1-copGFP中通过两步克隆,首先构建miRNA TuD通用骨架质粒,进一步构建特异性针对大鼠miR-203的TuD表达载体。在293T细胞中包装成慢病毒后,感染大鼠骨髓间充质干细胞(BM-MSCs),同时用pSIH1-H1-copGFP空质粒包装慢病毒,感染BM-MSCs作为对照。定量RT-PCR检测细胞中miR-203的水平变化,并用CCK-8法和Annexin V-PI双标记法分别检测BM-MSCs的活性和凋亡。结果成功构建了基于pSIH1-H1-copGFP质粒的miR-203 TuD表达载体,并对其序列进行了验证。用表达miR-203 TuD的重组慢病毒感染BM-MSCs后第3、6、9天检测细胞内源性miR-203表达水平降低,同时细胞活性增高,凋亡比例降低,与对照组相比差异有统计学意义。结论两步克隆法构建miRNA TuD表达载体是一种简便高效的方法,其表达产物能够有效抑制细胞内源性miRNA水平,同时影响细胞表型。

核转录因子decoy及其抗肿瘤的研究进展

核转录因子decoy技术是指应用人工合成与转录因子作用的顺式作用元件相一致的高亲和力的寡核苷酸转染细胞,竞争性抑制转录因子,使转录因子丧失与内源性基因作用的能力,或从作用部位脱离,导致基因表达抑制,最终达到基因治疗和基因调控的目的。现就其抗肿瘤的研究进展予以综述。

靶向转录因子AP-2的Decoy核酸对肿瘤细胞增殖的抑制作用

ecoy核酸是与靶转录因子具有高亲和性的双链寡聚核酸 ,通过竞争性抑制转录因子与调控区域的结合 ,调控转录来改变下游基因的异常表达 ,从而抑制肿瘤恶性增殖 .用MTT比色法 ,体外筛选结合转录因子AP 2的decoy核酸药物 ,结果K2 0 6对多种肿瘤细胞生长有显著的抑制作用 ,在异植人肿瘤细胞NCI H4 6 0的裸鼠模型中 ,静脉注射高中低三剂量组的decoy核酸K2 0 6 ,抑瘤率分别达 71 8%、6 4 4 %及 5 7 3% (V V) .通过凝胶阻抑试验 ,验证了K2 0 6与转录因子产生特异性结合 .