All in one theranostic nanoplatform enables efficient anti-tumor peptide delivery for triple-modal imaging guided cancer therapy

Developing a reliable system to efficiently and safely deliver peptide drugs into tumor tissues still remains a great challenge since the instability of peptide drugs and low ability to traverse the cell membrane. Herein, we constructed a multifunctional nanoplatform based on porous europium/gadolinium (Eu/Gd)-doped NaLa(MoO₄)₂ nanoparticles (NLM NPs) to deliver antitumor peptide of B-cell lymphoma/leukemia-2-like protein 11 (BIM) for cancer therapy. The porous NLM NPs exhibited inherent photoluminescent, magnetic and X-ray absorbable properties, which enable them for triple-modal bioimaging, including fluorescence, magnetic resonance imaging (MRI) and computed tomography (CT). This triple-modal bioimaging can contribute to monitoring NLM NPs biodistribution and guiding therapy in vitro and in vivo. Furthermore, the NLM NPs showed negligible cytotoxicity in vitro and tissue toxicity in vivo. Importantly, NLM NPs could load the antitumor peptide of BIM and efficiently improve the resistance of peptide drugs to proteolysis. The BIM peptide was efficiently delivered into the tumor cells by NLM NPs, which can inhibit the growth and promote the apoptosis of cancer cells in vitro, significantly inhibit the tumor growth in vivo. Notably, NLM-BIM theranostic nanoplatform exhibits low systemic toxicity and fewer side effects in vivo. The NLM NPs can serve as a promising multifunctional peptide delivery nanoplatform for multi-modal bioimaging and cancer therapy.

     

放电电极对毛细管放电软X光激光的影响

自软X光激光发现以来,实现低激发阈、台式软X光激光一直是一个十分重要的研究方向.利用毛细管放电激励产生软X光激光,是实现台式软X光激光的主要方案之一.实验采用20 cm长的毛细管,利用X射线二极管(XRD)探测了毛细管放电抽运软X光46.9 nm激光输出.研究表明,放电电极的材料并不是影响激光输出质量的决定性因素.但考虑到电极元素的飞溅,在长时间的实验研究中,选择钼电极更为有利.电极形状在放电过程中只影响预脉冲的导通情况,而对激光影响并不大.在更长毛细管的实验中,选择锥状端面的电极将有利于预脉冲的导通,以便获得激光输出.     

Influence of Nb addition on microstructural evolution and compression mechanical properties of Ti-Zr alloys

In order to expand the application horizon of Ti-Zr based alloys,the influence of Nb content on phase composition,microstructural evolution and biomechanical properties is systematically studied.The phase and microstructural characterization of the as-cast alloys is carried out by X-ray diffraction,optical microscopy and transmission electron microscopy.The results reveal that Nb-containing Ti-Zr alloys transformed from single a phase→α+α+β phase single β phase double β phases with increasing Nb content.In the case of β-type alloys,the addition of Nb improves the bonding energy between atoms,reduces the grain size,increases the elastic modulus,improves the yield strength and renders superior work-hardening behavior.Moreover,the current study provides mechanistic insights into microstructural evolution and strengthening of Nb-containing Ti-Zr alloys with increasing Nb content.Herein,the addition of 5 at.% Nb resulted in an abnormal work hardening during compression deformation under the synergistic influence of stress-induced martensite transformation of β phase and stress-induced twinning of α phase.Moreover,the biomechanical properties are evaluated to demonstrate the potential of Nb-containing Ti-Zr alloys in biological applications.     

4,4′-Methylenebis(2,6-di-t-butylphenol) as filler in high-damping chlorinated polyethylene composites

Damping materials are widely used in the modern industry as a kind of material for reducing vibration. The high-damping composites consisting of chlorinated polyethylene (CPE) and 4,4′-Methylenebis(2,6-di-t-butylphenol) (AO-4426) were successfully prepared in this work. The microstructural and mechanical properties of the CPE/AO-4426 composites were systematically investigated by using SEM, DSC, FTIR, and DMA. From the SEM, most of hindered phenol was dissolved in the CPE matrix and formed a fine dispersion. The results of DSC and FTIR suggested that strong intermolecular interaction like the hydrogen bonding was formed between the AO-4426 and CPE. It was found that with the increase of AO-4426 content, a new transition appeared above the glass transition temperature of the CPE matrix, with higher glass transition temperature and higher tan δ value than the neat CPE. As expected, the hybrid displayed excellent performance and had exciting potential applications as a damping material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48321.     

高压断路器动作时间的体外检测

介绍了一套便携式的高压断路器动作参数的体外检测装置,以ZN4—10型真空断路器为对象进行了试验,提出了一种提取动作时间的方法——幅值法,并说明了关键在于检测点的选取及对试品动作特性的先验知识。     

Co源辐照对聚乙烯电缆护套材料真空出气性能影响

材料真空出气性能是卫星设计选材时的一个重要依据,辐照是对材料出气性能影响较为严重的一种空间环境因素。本文对Co源辐照(1.2×10~9rad,Si)前后的材料样品,进行100及125℃条件下真空出气参数试验;结合红外光谱、扫描电镜、热重分析测试手段,研究辐照环境对聚乙烯电缆护套材料(SF-30-35)出气性能的影响。研究表明:经过辐照后的聚乙烯电缆护套材料样品的总质量损失及可凝挥发物量真空出气参数显著增加;Co源辐照使材料性质发生很大变化,辐照前材料表面为韧性网状结构,辐照后材料表面明显硬化,力学性能由柔韧变为干脆易断;辐照使材料发生氧化断链及交联反应,真空出气试验时断链产生的分子逸出。上述结果说明辐照环境改变了电缆护套材料特性,加速了材料真空环境下的出气性能。     

A review of methods for spike sorting: the detection and classification of neural action potentials

The detection of neural spike activity is a technical challenge that is a prerequisite for studying many types of brain function. Measuring the activity of individual neurons accurately can be difficult due to large amounts of background noise and the difficulty in distinguishing the action potentials of one neuron from those of others in the local area. This article reviews algorithms and methods for detecting and classifying action potentials, a problem commonly referred to as spike sorting. The article first discusses the challenges of measuring neural activity and the basic issues of signal detection and classification. It reviews and illustrates algorithms and techniques that have been applied to many of the problems in spike sorting and discusses the advantages and limitations of each and the applicability of these methods for different types of experimental demands. The article is written both for the physiologist wanting to use simple methods that will improve experimental yield and minimize the selection biases of traditional techniques and for those who want to apply or extend more sophisticated algorithms to meet new experimental challenges.     

An Intelligent Robotic System Capable of Sensing and Describing Objects Based on Bimodal,Self-Powered Flexible Sensors

This study presents an intelligent soft robotic system capable of perceiving, describing, and sorting objects based on their physical properties. This work introduces a bimodal self-powered flexible sensor (BSFS) based on the triboelectric nanogenerator and giant magnetoelastic effect. The BSFS features a simplified structure comprising a magnetoelastic conductive film and a packaged liquid metal coil. The BSFS can precisely detect and distinguish touchless and tactile models, with a response time of 10 ms. By seamlessly integrating the BSFSs into the soft fingers, this study realizes an anthropomorphic soft robotic hand with remarkable multimodal perception capabilities. The touchless signals provide valuable insights into object shape and material composition, while the tactile signals offer precise information regarding surface roughness. Utilizing a convolutional neural network (CNN), this study integrates all sensing information, resulting in an intelligent soft robotic system that accurately describes objects based on their physical properties, including materials, surface roughness, and shapes, with an accuracy rate of up to 97%. This study may lay a robotic foundation for the hardware of the general artificial intelligence with capacities to interpret and interact with the physical world, which also serves as an interface between artificial intelligence and soft robots.     

链路感知的传感器网络空间范围查询处理算法

在无线传感器网络环境中,用户经常提交空间范围查询以获取网络某局部区域的统计信息,如最大温度、平均湿度等。现有的基于路线的空间范围查询处理算法假设节点通信模型为理想的圆盘模型,而实际的网络并不满足该假设,导致其能量消耗大且查询结果质量差。提出了一种链路感知的空间范围查询处理算法LSA,它根据网络拓扑和链路质量动态地将查询区域划分为若干个网格,依次收集各网格中节点的感知数据,以生成最终的查询结果。LSA算法通过遍历查询区域内的所有网格,保证了算法查询结果的质量。提出了启发式的网格划分方法以降低节点间数据通信的丢包率,给出链路感知的数据收集算法,以减少算法的能量消耗,提高查询结果的质量。通过仿真实验系统地分析和比较了LSA算法和现有的IWQE算法的能量消耗及查询结果质量,结果表明,在绝大多数情况下,LSA算法优于IWQE算法。     

Chemical Composition and Oxidative Stability of Selected Plant Oils

Scientific data on the oxidative stability of borage oil, Camelina sativa oil, linseed oil, evening primrose oil and pumpkin seed oil are scarce. Chemiluminescence (CL) methods most commonly used to determine the oxidative stability of oils include measurement of hydroperoxide, intensity of light emitted during the accelerated oxidation process performed at high (>100 °C) temperatures or assisted by forced flow of air/oxygen through the sample. The aim of this study was to investigate the chemical composition and oxidative stability of selected vegetable oils available on the Polish market. Oxidative stability was determined using a fast, novel chemiluminescence-based method, in which light emitted during oxidation process conducted at 70 °C in the presence of some catalyzing Fe²⁺ ions is measured. A reaction of the applied type has not been reported so far. High contents of tocopherols and phytosterols were found in the analyzed oil samples. Oxidative stability of the samples was in most cases higher than the stability of refined rapeseed oil, a relatively stable substance from the oxidation point of view.