Biodegradable Nanoscale Coordination Polymers for Targeted Tumor Combination Therapy with Oxidative Stress Amplification

Nowadays various inorganic nanoparticles that generate highly reactive hydroxyl radical ( · OH) on the basis of Fenton‐like catalytic activity of metal ions have been designed for chemodynamic therapy. However, the high level of adaptive antioxidants [glutathione (GSH)] in cancer cells could effectively consume · OH to compromise the treatment efficiency and biosafety of these inorganic nanoparticles, and this is a general concern in chemodynamic therapy. Herein, a new biodegradable nanoscale coordination polymer (NCP) is developed by integration of cisplatin prodrug (DSCP) and iron (III) ions through a reverse microemulsion method. The DSCP in the NCPs could react with GSH to release free cisplatin, while the iron (III) ions could be reduced by GSH into iron (II) to enable Fenton reaction, subsequently leading to amplified intracellular oxidative stress. After surface modification of polyethylene glycol (PEG) and cyclo[Arg‐Gly‐Asp‐D‐Phe‐Lys(mpa)] peptide (cRGD), Fe‐DSCP‐PEG‐cRGD shows an excellent targeting effect against α_vβ₃‐integrin overexpressed tumor cells. Furthermore, Fe‐DSCP‐PEG‐cRGD enables significant chemo and chemodynamic therapy with dramatically enhanced therapeutic efficiency in comparison to relative monotherapies. Importantly, Fe‐DSCP‐PEG‐cRGD could be efficiently cleared out from mice through feces and urine postinjection 7 days. The NCP presented in this work is simple and economical, which shows great biodegradability and biosafety for potential clinical translation.     

一种适应高多普勒频偏的突发传输高效导频图案

导频符号辅助调制技术广泛应用于数字通信系统的突发传输。在频偏范围较大和信噪比较低时,现有的前后式导频方案的频偏估计误差会远高于理论下界。该文研究了频偏估计最大似然检测量的主瓣和旁瓣分布,分析了对称分布导频图案在频偏估计时的模糊问题。在此基础上提出了一种新的混合对称式导频图案,并给出了相应的参数选取原则。新导频图案能够在较低的信噪比下具有大的频偏估计范围和较高的估计精度。仿真结果验证了新导频图案的良好性能。     

基于SM2密码体系的电力信息安全监控系统设计

以往使用传统RSA算法、神经网络算法的密钥长,签名和验签速度慢,导致监控效果不佳,针对该现象,提出了基于SM2密码体系的电力信息安全监控系统设计.根据系统硬件结构,采用DS18B20传感器计量数据采集时钟脉冲,完成电力信息采集.设计间歇振荡服务加密接口电路,控制系统电压和电流.通过视频联动,达到监控互动与协调,实现远程...     

Luminescence Properties of Aminobenzanthrones and Their Application as Host Emitters in Organic Light‐Emitting Devices

A series of aminobenzanthrone derivatives, possessing a keto and an amino group on the aromatic ring, are synthesized and their photoluminescence (PL) and electroluminescence (EL) properties are studied in detail. These compounds emit strongly in solution and in the solid state, with the emission maxima in the range of 528–668 nm resulting from charge‐transfer transitions from the amino group to the keto moiety. The emission wavelength depends greatly on the polarity of the solvent. A red shift of nearly 100 nm is observed from n‐hexane to dichloromethane for each of these compounds. The PL quantum yields of these molecules also depend tremendously on the solvent. The values are between 88 and 70 % in n‐hexane and decrease as the polarity of the solvent increases. The single‐crystal X‐ray diffraction data reveal that the aminobenzanthrone planes of these molecules stack in the crystals in an antiparallel head‐to‐tail fashion. This strong dipole–dipole interaction accounts for the observed red‐shifted emissions of the aminobenzanthrone molecules in powders and in films relative to those in nonpolar solvents. Electroluminescent devices using aminobenzanthrone derivatives as the host emitters or dopants emit orange to red light in the range 590–645 nm. High brightness, current efficiency, and power efficiency are observed for some of these devices. For example, the device using N‐(4‐t‐butylphenyl)‐N‐biphenyl‐3‐benzanthronylamine as the emitter gives saturated red light with a current efficiency of 1.82 cd A^–1, brightness of 11 253 cd m^–2, and Commission Internationale de l'Éclairage (CIE) coordinates of (0.64,0.36); the device using N‐(2‐naphthyl)‐N‐phenyl‐3‐benzanthronylamine as the emitter gives orange–red light with a current efficiency of 3.52 cd A^–1, brightness of 25 000 cd m^–2, and CIE coordinates of (0.61,0.38).     

丹参提取物与几种抗氧化剂在浓缩EPA和DHA中的抗氧化作用比较

本文比较了丹参提取物（ＳＭＥＣ）、茶多酚、ＴＢＨＱ、ＢＨＴ等几种抗氧化剂在浓缩ＥＰＡ和ＤＨＡ中的抗氧化作用的强弱，表明，在相同浓度下，丹参提取物的抗氧化作用不如茶多酚、ＢＨＴ及ＴＢＨＱ，丹参提取物及茶多酚的抗氧化作用均随浓度的升高而加强，丹参提取物与ＢＨＴ或ＴＢＨＱ有阶同作用，共同使用可大大增强抗氧化作用。     

超代数结构的几个问题

讨论了群的超群上的超群，超环以有自由群上的超群等问题。     

Digesting Commercial Clips from TV Streams

A commercial system that performs syntactic and semantic analysis during a TV advertising break could facilitate innovative new applications, such as an intelligent set-top box that enhances the ability of viewers to monitor and manage commercials from TV streams.     

Phase correlation between longitudinal modes in semiconductor self-pulsating DBR lasers

Phase correlation leading to self-pulsation (SP) in semiconductor distributed Bragg reflector (DBR) lasers is investigated experimentally and theoretically. Under proper biasing conditions, the laser oscillates with three main modes and we observe that each two-modes beating provides SP with identical spectral linewidth. Under the same operating conditions, the measured spectral linewidths of the beating modes are much larger than the linewidth of the self-pulsating signal. These results demonstrate the natural occurrence of passive mode-locking (PML) and phase correlation in semiconductor DBR lasers. A model based on multimode coupled-wave rate equations, including four-wave mixing (FWM), is developed to describe PML and SP in the gain region of the laser cavity. This model demonstrates that the existence of phase correlation between longitudinal modes is due to FWM.     

钨柱对40Cr侵彻效应影响的研究

在实验的基础上,运用数值仿真方法研究了长径比约为1∶1钨柱的着靶姿态对40Cr钢板侵彻效应的影响。获得了入射角与极限穿透速度的关系,以及侵彻速度相同时,入射角与穿透靶板后剩余速度的关系。在此基础上研究了同种规格的钨柱侵彻不同厚度的均质装甲钢和40Cr钢板时极限穿透速度的关系,得到了两者速度比为1.13∶1的结论,为寻求低成本等效靶板提供了有效试验依据。这些研究成果对破片毁伤战斗部的设计具有实际指导意义。