2019年水环境安全热点回眸

 水是生命之源，水环境安全是人类生存与发展的必要条件。2019年，水污染控制、地表水生态环境、地下水环境保护等领域科技进展显著。本文围绕水资源、水生态、水环境，介绍了2019年生活污水与工业废水污染控制、地表水生态流量与氮排放限值、地下水资源保护与污染防控等方面的全球科技研究热点及亮点工作，回顾了中国水环境安全的2019年。     

A high-resolution map of human evolutionary constraint using 29 mammals

The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ～4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ～60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease.     

浅议房地产开发与居民居住的关系

文章主要谈到了房地产与居民居住的关系,首先阐述了房地产公司的行业特性,正是它的行业特性决定了它与改善居民居住环境的关系,同时居民居住需求也反作用于房地产公司的定位。     

有线局域网的安全分析与解决方案

从以太网的特点、共享和服务、面对攻击等方面，对局域网的安全问题进行了分析，提出在网络不断发展的情况下．网络的安全环境也会随之改变，需要不断更新技术，以便采取相应的措施来确保网络畅通。     

pSOS操作系统任务管理的分析

本文对pSOS实时微内核操作系统的任务状态、任务调度方式、优先级别进行了分析，并对有关任务的数据结构及系统调用进行了详细的阐述。     

注塑模 CAD/CAE/CAM 的研究现状与发展方向

在综述国内外注塑模ＣＡＤ／ＣＡＥ／ＣＡＭ研究成果的基础上，对典型的研究方法和关键技术进行了评述．结合我国国情，提出了注塑模ＣＡＤ／ＣＡＥ／ＣＡＭ的发展方向．