Clostridiumnovyi’s Alpha-Toxin Changes Proteome and Phosphoproteome of HEp-2 Cells

C. novyi type A produces the alpha-toxin (TcnA) that belongs to the large clostridial glucosylating toxins (LCGTs) and is able to modify small GTPases by N-acetylglucosamination on conserved threonine residues. In contrast, other LCGTs including Clostridioides difficile toxin A and toxin B (TcdA; TcdB) modify small GTPases by mono-o-glucosylation. Both modifications inactivate the GTPases and cause strong effects on GTPase-dependent signal transduction pathways and the consequent reorganization of the actin cytoskeleton leading to cell rounding and finally cell death. However, the effect of TcnA on target cells is largely unexplored. Therefore, we performed a comprehensive screening approach of TcnA treated HEp-2 cells and analyzed their proteome and their phosphoproteome using LC-MS-based methods. With this data-dependent acquisition (DDA) approach, 5086 proteins and 9427 phosphosites could be identified and quantified. Of these, 35 proteins were found to be significantly altered after toxin treatment, and 1832 phosphosites were responsive to TcnA treatment. By analyzing the TcnA-induced proteomic effects of HEp-2 cells, 23 common signaling pathways were identified to be altered, including Actin Cytoskeleton Signaling, Epithelial Adherens Junction Signaling, and Signaling by Rho Family GTPases. All these pathways are also regulated after application of TcdA or TcdB of C. difficile. After TcnA treatment the regulation on phosphorylation level was much stronger compared to the proteome level, in terms of both strength of regulation and the number of regulated phosphosites. Interestingly, various signaling pathways such as Signaling by Rho Family GTPases or Integrin Signaling were activated on proteome level while being inhibited on phosphorylation level or vice versa as observed for the Role of BRCA1 in DNA Damage Response. ZIP kinase, as well as Calmodulin-dependent protein kinases IV & II, were observed as activated while Aurora-A kinase and CDK kinases tended to be inhibited in cells treated with TcnA based on their substrate regulation pattern.     

Coagulation Factor XIIIa and Activated Protein C Activate Platelets via GPVI and PAR1

Platelet and coagulation activation are highly reciprocal processes driven by multi-molecular interactions. Activated platelets secrete several coagulation factors and expose phosphatidylserine, which supports the activation of coagulation factor proteins. On the other hand, the coagulation cascade generates known ligands for platelet receptors, such as thrombin and fibrin. Coagulation factor (F)Xa, (F)XIIIa and activated protein C (APC) can also bind to platelets, but the functional consequences are unclear. Here, we investigated the effects of the activated (anti)coagulation factors on platelets, other than thrombin. Multicolor flow cytometry and aggregation experiments revealed that the ‘supernatant of (hirudin-treated) coagulated plasma’ (SCP) enhanced CRP-XL-induced platelet responses, i.e., integrin α_IIbβ₃ activation, P-selectin exposure and aggregate formation. We demonstrated that FXIIIa in combination with APC enhanced platelet activation in solution, and separately immobilized FXIIIa and APC resulted in platelet spreading. Platelet activation by FXIIIa was inhibited by molecular blockade of glycoprotein VI (GPVI) or Syk kinase. In contrast, platelet spreading on immobilized APC was inhibited by PAR1 blockade. Immobilized, but not soluble, FXIIIa and APC also enhanced in vitro adhesion and aggregation under flow. In conclusion, in coagulation, factors other than thrombin or fibrin can induce platelet activation via GPVI and PAR receptors.     

基于智能型电动机保护器的监控系统设计与实现

针对目前电动机保护器的在使用过程中的特点,介绍了一种基于智能型的可通信电动机保护器的监控系统的设计方案。上位机与可通信电动机保护器依靠现场总线技术组成监控网络。简单介绍了现场总线技术、MODBUS通信协议,用Visualc＋＋设计了一种上位机监控软件,并对监控软件的关键技术做了介绍。     

Ceramic thermal wind sensor based on advanced direct chip attach package

An advanced direct chip attach packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct chip attach (DCA) packaging is adopted and this new packaged method simplifies the processes of packaging further. Simulations of the advanced DCA packaged sensor based on computational fluid dynamics (CFD) model show the sensor can detect wind speed and direction effectively. The wind tunnel testing results show the advanced DCA packaged sensor can detect the wind direction from 0° to 360° and wind speed from 0 to 20 m/s with the error less than 0.5 m/s. The nonlinear fitting based least square method in Matlab is used to analyze the performance of the sensor.     

一种新的适用于面向对象程序设计语言的保守式垃圾收集机制

主要研究了在缺乏运行时环境支持的情况下,如何为面向对象程序设计语言构建保守式垃圾收集机制的问题.传统的解决方案存在两大主要缺陷:1)指针定位不准确,容易出现内存泄漏;2)应用传统的标记-清扫算法,在清扫阶段执行效率低下.结合面向对象程序设计语言的特点提出了一种新的保守式垃圾收集机制,能够有效地解决这些问题,从而提高了程序运行的鲁棒性和效率,并以C 语言为例进行了具体实现.     

三层链式客户/服务模型及其分析

为了改进传统的2层客户/服务结构的缺陷,提出了3层链式客户/服务计算模型,研究了其中间层任务的分布.     

基于MQTT协议的一次设备触点温度测量的方案

本文针对一次设备触点温度难监控等问题,设计了一个基于消息队列遥测传输(MQTT)协议的温度测量方案.该方案采用嵌入式集成模块ESP32作为主控,结合温度传感器、烟雾传感器等设备实现对触点温度的实时监测,并利用时间序列数据库InfluxDB和前端可视化框架Grafana设计了温度监控系统.     

基于Visual C++与MATLAB的数字基带传输系统仿真的实现

论述了通过Visual C 6．0与MATLAB应用程序接口,利用VC强大的用户界面开发功能和Matlab具备的复杂数据处理及绘图能力,实现了对数字基带传输系统的仿真,并探讨了此方法在通信系统仿真中的应用前景。     

基于C8051F340双串口电梯远程控制的系统设计

采用双串口高速单片机C8051F340作为电梯远程控制系统的主控芯片,通过RS－485连接电梯外呼板进行顾客所需要的升降等控制。同时通过RS－232与西门子PLC进行串行通讯以便进行总调度,此外还通过公共电话网与服务器连接,实现电梯远程报警、运行状态信息记录和服务器主动呼叫查询等功能[1]。最后,设计了IC卡的输入输出电路,保障了系统可靠性和顾客的安全性。     

Microstructural evolution of a silicon carbide-carbon coated nanostructured ferritic alloy composite during in-situ Kr ion irradiation at 300℃ 450℃

This work focuses on irradiation behaviors of a novel silicon carbide and carbon coated nanostructured ferritic alloy (SiC-C@NFA) composite for potential applications as a cladding and structural material for next generation nuclear reactors.The SiC-C@NFA samples were irradiated with 1 MeV Kr ions up to 10 dpa at 300 and 450 ℃.Microstructures and defect evolution were studied in-situ at the IVEM-Tandem facility at Argonne National Laboratory.The effects of ion irradiation on various phases such as α-ferrite matrix,(Fe,Cr)7C3,and (Ti,W)C precipitates were evaluated.The α-ferrite matrix showed a continuous increase in dislocation density along with spatial ordering of dislocation loops (or loop strings) at ＞5 dpa.The size of the dislocation loops at 450 ℃ was larger than that at 300 ℃.The nucleation and growth of new (Ti,W)C precipitates in α-ferrite grains were enhanced with the ion dose at 450 ℃.This study provides new insight into the irradiation resistance of the SiC-C@NFA system.