利用DTMF技术实现电力线载波通信

介绍一种基于DTMF编码的电力线载波系统，该系统由双音频（DTMF）编译码芯片HT9200和MT8870、模拟乘法器MC1496和电力线耦合器组成。通过对系统组成原理的介绍，详细论述了系统的设计过程以及为了保证其通信的可靠性而采取的干扰和软件纠错措施。试验证明，该系统充分发挥了DTMF的优良性，是一套低成本的电力线载波数据通信系统。     

MPLS在虚拟专用网中的应用

首先阐述了虚拟专用网（VPN）和多协议标记交换（MPLS）技术的概念，又描述了MPLS协议在虚拟专用网建设中的应用。主要就MPLS技术应用于虚拟专用网的优势、MPLSVPN的网络结构、内部机制、工作过程及其完全性做了论述。     

鳜传染性脾肾坏死病毒ICR489基因序列分析

报道了鳜鱼传染性脾肾坏死病毒 (ISKNV)的ICR489基因结构及其序列分析。对ISKNVDNAKpnⅠB酶切片段的序列分析结果发现该序列中含有完整的ICR489基因。ISKNVICR489基因完整读码框为 10 11bp ,GC含量为 5 6 97% ,等电点为 6 82 ,编码一个长为 337aa、相对分子质量为 382 70的推定蛋白。结构分析发现该基因起始密码子上游具有启动子元件TATAbox,有反向重复序列可形成茎环 ,并有一段回文序列。ISKNV与其它 3种虹彩病毒 (FV3、RRV和LCDV_1)的ICR489基因氨基酸序列具有一定的同源性 ,但ISKNV与它们的同源性不高 ,序列比较和系统树分析发现ISKNV与蛙病毒属和淋巴囊肿病毒属的病毒都不尽相同     

煤基炭材料用作锂离子电池负极

以煤为前驱体，经700－1000℃炭化制得煤基炭材料，用X射线衍射和恒电流法研究了炭材料微晶结构的变化以及放电性能。研究发现，随着热处理温度的增加，煤基炭材料的微晶结构逐渐变得规整，首次放电容量下降。     

基于符合变量运算的状态空间方程离散化

针对MATLAB控制系统工具箱中模型转换命令，不能对带符合变量连续状态空间方程进行离散化，提出借助符合数学工具箱中有关符合对象函数构成M文件，自动完成此过程，该方法与常规方法所得结果比较，两者完全一致，证明此方法的正确性和实用性。     

基于符号对象函数的状态反馈调节系统的CAD

针对MATLAB控制系统工具箱中极点配置函数 ,不能完成状态反馈调节系统计算问题 ,提出借助符号数学工具箱中有关符号对象函数 ,构成M文件 ,自动完成设计过程。该方法计算结果与仿真结果比较 ,两者完全一致 ,证明此方法的正确性和实用性     

An index to assess the health and benefits of the global ocean

The ocean plays a critical role in supporting human well-being, from providing food, livelihoods and recreational opportunities to regulating the global climate. Sustainable management aimed at maintaining the flow of a broad range of benefits from the ocean requires a comprehensive and quantitative method to measure and monitor the health of coupled human–ocean systems. We created an index comprising ten diverse public goals for a healthy coupled human–ocean system and calculated the index for every coastal country. Globally, the overall index score was 60 out of 100 (range 36–86), with developed countries generally performing better than developing countries, but with notable exceptions. Only 5% of countries scored higher than 70, whereas 32% scored lower than 50. The index provides a powerful tool to raise public awareness, direct resource management, improve policy and prioritize scientific research.     

Roles of tumour localization, second signals and cross priming in cytotoxic T-cell induction.

The vertebrate immune system has evolved to protect against infections that threaten survival before reproduction. Clinically manifest tumours mostly arise after the reproductive years and somatic mutations allow even otherwise antigenic tumours to evade the attention of the immune system. Moreover, the lack of immunological co-stimulatory molecules on solid tumours could result in T-cell tolerance; that is, the failure of T cells to respond. However, this may not generally apply. Here we report several important findings regarding the immune response to tumours, on the basis of studies of several tumour types. First, tumour-specific induction of protective cytotoxic T cells (CTLs) depends on sufficient tumour cells reaching secondary lymphatic organs early and for a long enough duration. Second, diffusely invading systemic tumours delete CTLs. Third, tumours that stay strictly outside secondary lymphatic organs, or that are within these organs but separated from T cells by barriers, are ignored by T cells but do not delete them. Fourth, co-stimulatory molecules on tumour cells do not influence CTL priming but enhance primed CTL responses in peripheral solid tumours. Last, cross priming of CTLs by tumour antigens, mediated by major histocompatibility complex (MHC) class I molecules of antigen-presenting host cells, is inefficient and not protective. These rules of T-cell induction and maintenance not only change previous views but also rationales for anti-tumour immunotherapy.