基于嵌入式Linux可扩展路由器的设计

基于嵌入式Linux可扩展路由器硬件结构由X86平台、控制台、双启动U盘、以太网口、串行口组成.对硬件平台、接口和外设驱动程序以及路由新特性的支持,采用Linux kernel 2.4或更高版本.路由功能利用源代码开放软件Zebra实现.控制台主控界面用CISH实现,前台为用户提供模拟路由器操作系统界面,后台通过参数传递与Linux系统内相关命令相连.     

Comparative Genomics Reveals 13 Different Isoforms of Mytimycins (A-M) in Mytilus galloprovincialis

Mytimycins are cysteine-rich antimicrobial peptides that show antifungal properties. These peptides are part of the immune network that constitutes the defense system of the Mediterranean mussel (Mytilus galloprovincialis). The immune system of mussels has been increasingly studied in the last decade due to its great efficiency, since these molluscs, particularly resistant to adverse conditions and pathogens, are present all over the world, being considered as an invasive species. The recent sequencing of the mussel genome has greatly simplified the genetic study of some of its immune genes. In the present work, we describe a total of 106 different mytimycin variants in 16 individual mussel genomes. The 13 highly supported mytimycin clusters (A–M) identified with phylogenetic inference were found to be subject to the presence/absence variation, a widespread phenomenon in mussels. We also identified a block of conserved residues evolving under purifying selection, which may indicate the “functional core” of the mature peptide, and a conserved set of 10 invariable plus 6 accessory cysteines which constitute a plastic disulfide array. Finally, we extended the taxonomic range of distribution of mytimycins among Mytilida, identifying novel sequences in M. coruscus, M. californianus, P. viridis, L. fortunei, M. philippinarum, M. modiolus, and P. purpuratus.     

Dreissenid colonization during the initial invasion of the quagga mussel in the largest Central European shallow lake,Lake Balaton,Hungary

The colonization progress of the invasive bivalve dreissenids, the formerly dominant Dreissena polymorpha and the recently (2008) introduced Dreissena rostriformis bugensis was studied between 2009 and 2013 in the largest Central European shallow lake, Lake Balaton, Hungary. The density of dreissenid planktonic veligers, new settlers (post-veligers and early juveniles), and the population structure (density, length frequency, relative abundance) of the two species were monitored on experimentally introduced natural stone substrata, on different time scales. Dreissenids started dynamic settling following a sudden veliger bloom. As substratum saturation progressed, competition between species for places was suggested, which, after two years, led to an increased number of large individuals (> 20 mm) and also recruits of D. r. bugensis. By contrast, the population of D. polymorpha was confined to middle size (11–18 mm) individuals of the first settler generation. On local substrata, where the benthic community was already established, the replacement of D. polymorpha by D. r. bugensis took longer, but it happened in a similar way. The invasion speed of D. r. bugensis in Lake Balaton resembled the speed obtained in other European water bodies where D. r. bugensis, similar to Lake Balaton, was introduced much later than D. polymorpha. However, a longer replacement process was found in North America, where both species invaded new habitats at the same time. This suggests that the speed, and probably the success, of D. r. bugensis invasion depends on new surface availability, and whether the two dreissenid species are introduced together or at different times.     

Association of aerobic anoxygenic phototrophs and zebra mussels,Dreissena polymorpha,within the littoral zone of Lake Winnipeg

While nutrient loading has affected all levels of Lake Winnipeg’s ecology, its greatest influence has likely been on the microbial community. In addition to eutrophication, zebra mussels (Dreissena polymorpha) have recently invaded the ecosystem and threaten food web dynamics. Their filter-feeding predation and association with bacteria, specifically phototrophs, was investigated. A sampling trip to Lake Winnipeg in October 2017, focused on the isolation, enumeration, and identification of aerobic anoxygenic phototrophs in littoral water, sediment, and tissues of mussels. Gimli, Patricia, and Grand beaches, separated by >15 km across the South Basin, had similar bacterial counts when cultivated on rich organic, BG-11, purple non-sulphur, and K₂TeO₃-supplemented media. Culture-based enumeration on rich organic medium revealed 1.74% of heterotrophs from littoral waters were aerobic anoxygenic phototrophs, and represented 13.98% within sediments. In contrast, 0.48, 1.15, and 0.16% of cultured heterotrophs were aerobic anoxygenic phototrophs within zebra mussel gill, gut, and gonadal tissues, respectively. High-throughput sequencing of bacterial 16S V4 rDNA maintained similar trends in respective bivalve organs, where 0.22, 1.13, and 0.20% of total 16S genes belonged to these phototrophs. Several Sphingomonadaceae isolates were recovered from gut tissues, all with filamentous morphology large enough for predation. Bioaccumulation of metals was also studied in D. polymorpha. All tested associated aerobic anoxygenic phototrophs were capable of resisting the metalloid oxide tellurite. The consistent distribution of aerobic anoxygenic phototrophs within microbial communities across Lake Winnipeg, and their predominance in the gut tissues of zebra mussels suggested bacterial consumption by this invasive species.     

Mussel‐Inspired Hydrogels for Self‐Adhesive Bioelectronics

Wearable and implantable bioelectronics are receiving a great deal of attention because they offer huge promise in personalized healthcare. Currently available bioelectronics generally rely on external aids to form an attachment to the human body, which leads to unstable performance in practical applications. Self‐adhesive bioelectronics are highly desirable for ameliorating these concerns by offering reliable and conformal contact with tissue, and stability and fidelity in the signal detection. However, achieving adequate and long‐term self‐adhesion to soft and wet biological tissues has been a daunting challenge. Recently, mussel‐inspired hydrogels have emerged as promising candidates for the design of self‐adhesive bioelectronics. In addition to self‐adhesiveness, the mussel‐inspired chemistry offers a unique pathway for integrating multiple functional properties to all‐in‐one bioelectronic devices, which have great implications for healthcare applications. In this report, the recent progress in the area of mussel‐inspired self‐adhesive bioelectronics is highlighted by specifically discussing: 1) adhesion mechanism of mussels, 2) mussel‐inspired hydrogels with long‐term and repeatable adhesion, 3) the recent advance in development of hydrogel bioelectronics by reconciling self‐adhesiveness and additional properties including conductivity, toughness, transparency, self‐healing, antibacterial properties, and tolerance to extreme environment, and 4) the challenges and prospects for the future design of the mussel‐inspired self‐adhesive bioelectronics.     

Bioinspired Ultratough Hydrogel with Fast Recovery,Self‐Healing,Injectability and Cytocompatibility

Inspired by the mussel byssus adhesiveness, a highly hydrated polymeric structure is designed to combine, for the first time, a set of interesting features for load‐bearing purposes. These characteristics include: i) a compressive strength and stiffness in the MPa range, ii) toughness and the ability to recover it upon successive cyclic loading, iii) the ability to quickly self‐heal upon rupture, iv) the possibility of administration through minimally invasive techniques, such as by injection, v) the swelling ratio being adjusted to space‐filling applications, and vi) cytocompatibility. Owing to these characteristics and the mild conditions employed, the encapsulation of very unstable and sensitive cargoes is possible, highlighting their potential to researchers in the biomedical field for the repair of load‐bearing soft tissues, or to be used as an encapsulation platform for a variety of biological applications such as disease models for drug screening and therapies in a more realistic mechanical environment. Moreover, given the simplicity of this methodology and the enhanced mechanical performance, this strategy can be expanded to applications in other fields, such as agriculture and electronics. As such, it is anticipated that the proposed strategy will constitute a new, versatile, and cost‐effective tool to produce engineered polymeric structures for both science and technology.     

基于聚多巴胺的超疏水棉织物的一锅法制备及其油水分离性能

将棉织物浸入多巴胺、硝酸银、十六烷基三甲氧基硅烷的乙醇溶液中,取出烘干制备出超疏水棉织物。用扫描电子显微镜和X射线光电子能谱表征其表面形貌和元素,用接触角测量仪测量其接触角并进行摩擦或液体浸泡(如酸、碱、沸水)实验检测其耐用性。结果表明,聚多巴胺的强附着性使原位生成的银纳米粒子能经受摩擦或不同液体的浸泡,从而使超疏水织物具有良好的耐用性。超疏水棉织物还具有良好的油水分离性能,其油水分离效率高达97%,油流量最高可达15.93 m³·m^-2·h^-1。     

一种针对路口监控图像的区域分割方法

针对智能交通系统中对交通路口场景理解的需求,提出一种基于线特征先验和凸包损失函数的空间分割网络,目标是对斑马线以及斑马线所围路口区域进行精确检测和分割。利用公安交通管理系统平台采集并标注路口数据集;引入线特征先验,将RGBL图像作为网络输入,为深度学习实例分割提供显著的物体边缘特征以加强深度网络对图像特征学习的针对性;在分割网络中引入SCNN网络结构,构成空间分割网络以增强网络对空间结构的学习;引入凸包二值交叉熵动态损失函数来优化网络的输出精度。实验结果表明,该空间分割网络对斑马线及路口区域的检测正确率和分割完整度和精确度都有了显著的提升。     

Use of Potassium for Treatment and Control of Zebra Mussel Infestation in Industrial Fire Protection Water Systems

Zebra mussels, first discovered in the Great Lakes in 1988, have frequently been detected in fire protection systems. However, the potential for large-scale infestations has not been established. It is clear that even small numbers of mussels can cause problems in areas that have small-diameter piping or in sprinkler system nozzles, if shells are flushed down-stream during emergency use.This paper will discuss the development of a method of zebra mussel control that limited interference with normal system operations when used at Niagara Mohawk's Dunkirk Steam Station. Because oxygen is often depressed in these systems and limits mussels survival and growth, it was established that by monitoring oxygen alone, or in combination with veliger or mussel larval monitoring, high-risk areas for mussel infestation could be determined. In previous laboratory research, it had already been determined that concentrations of potassium in excess of 100 mg/L would lead to quick mortality in adult zebra mussels. These results, along with a biofouling risk assessment completed at Dunkirk Steam Station, were used to develop and implement a successful treatment of the high-risk areas in the plant's fire protection water systems using potassium in the form of potash as the controlling agent.