Molecular Origin of pH‐Dependent Fibril Formation of a Functional Amyloid

Fibrils derived from Pmel17 are functional amyloids upon which melanin is deposited. Fibrils of the repeat domain (RPT) of Pmel17 form under strict melanosomal pH (4.5–5.5) and completely dissolve at pH≥6. To determine which Glu residue is responsible for this reversibility, aggregation of single, double, and quadruple Ala and Gln mutants were examined by intrinsic Trp fluorescence, circular dichroism spectroscopy, and transmission electron microscopy. Charge neutralization of E404, E422, E425, or E430, which are located in the putative amyloid‐forming region, modulated aggregation kinetics. Remarkably, the removal of a single negative charge at E422, one of 16 carboxylic acids, shifted the pH dependence by a full pH unit. Mutation at E404, E425, or E430 had little to no effect. We suggest that protonation at E422 is essential for initiating amyloid formation and that the other Glu residues play an allosteric role in fibril stability.     

一种可靠的红外通信协议设计与实现

介绍了一种可靠的红外通信协议设计方法.该方法采用自动重传的停止等待协议,即源点传输一数据帧后,必须等待一个确认;在终点的确认返回源点之前,源点不能发送其他的数据帧;如出错,则尝试重发,最多3次.通过实验,找到了比较适宜的等待时间,在实际应用中有较好的效果,可靠性得到提高.     

电力线通信自适应中继路由算法

电力线通信为配电自动化业务的开展提供了廉价的数据通信平台,但由于配电网具有网络拓扑未知和信道时变的特点,会导致可靠性降低和通信距离存在不足,这些问题很难在物理层进行解决,需要通过上层的通信协议来解决。为此提出一种自适应的路由算法,通过此算法可以形成节点之间的正常路由功能和链路修复功能,以增大电力线载波通信的通信距离,并提高其可靠性。仿真结果表明,该算法能够快速有效地找到网络协调节点到目的节点的路由。     

农村配电网线路和设备的防雷接地保护研究

针对1起10 kV配电变压器高压侧避雷器爆炸引起的低压侧用户电击死亡事件,分析农村配电网的防雷保护和低压配电线路上用户的电气安装等问题,并提出相应的修改措施。     

光学定量取样系统的研究与设计

该文针对设计化学需氧量分析仪的定量取样装置,以TI的TMS320F2808控制核心,采用光学定量的方法,实现液体的精确定量。光学定量完全采用数字化方式,将光射过凹形液面后的强度通过量化,再由DSP采集分析。该结果于在线检测领域的应用前景十分广阔。     

激光涂层低应力多冲形变分析

通过对带涂层试样的多冲试验，对不同冲击次数下涂层和基体的厚度变化进行对比，发现即使在低于材料屈服极限的冲击应力下，材料也会产生宏观塑性变形。针对实验条件及结果，对此现象产生的原因进行了分析。     

利用微机模拟梭子调配的探讨

本文在全面分析了影响织机梭子调配的有关因素的基础上,利用微机对给定的纬纱配色循环,首先判断调配的可行性,然后自动完成梭子调配,操作过程具有简单可靠的特点。     

联合网络编码与HARQ的中继传输协议及跨层优化设计

为了进一步提高中继系统的可靠性和频谱效率,提出了联合固定网络编码与混合自动重传请求(DNC-HARQ)和联合随机网络编码与混合自动重传请求(ONC-HARQ)2种传输协议,分析了这两种传输协议的系统中断概率和频谱效率.以最大化系统频谱效率为优化目标进行跨层优化设计,并利用迭代算法求解.仿真结果表明,DNC-HARQ和ONC-HARQ传输协议比只采用网络编码的传输协议具有更高的系统可靠性,比仅采用HARQ的传输协议具有更高的频谱效率;所提出的基于最大化频谱效率的跨层优化算法能有效地最大化系统频谱效率.     

D2D communication in a cellular network based on link adaptation with truncated ARQ

A device-to-device （D2D） communication mode underlaying cellular network in a single- cell environment is introduced. A practical method based on link adaptation with automatic repeat request （ARQ） is presented. Link adaptation technique, which combines adaptive modulation and coding （ AMC ） with truncated ARQ, can maximize the cellular UEs＇ data rate under prescribed delay and performance constraints. The proposed method can maximize the total transmission rate when an outage probability is determined. Numerical results show that with proper power control, the in- terference between the two links can be coordinated to increase the sum rate without overwhelming the cellular service.