简介:Thousandsofyearsago,Britainwascoveredbythickforests,hometomanyanimalswhichnolongerliveintheUnitedKingdom.Therewerewolvesandbears,manydifferenttypesofdeerandmassivewildcattlecalledaurochs.Therewerelessthanfourmillionpeople.Theylivedinsmallvillagesprotectedbywoodenwallsfromtheanimalsoutside.
简介:女巫攻击是反对联机社会网络(OSN)的一个种著名、强大的攻击。在女巫攻击,一个恶意的攻击者产生由多重女巫用户组成的一个女巫组,并且控制他们攻击系统。然而,主要社会网络供应商的数据机密政策严重地限制了研究人员存取到女巫组的大规模数据集。女巫组的深理解能在安全机制的设计上提供重要卓见进恶意的行为,以及众多的实际含意的特征。在这份报纸,我们在场测量女巫的起始的研究在大规模OSN组织,Renren。我们在不同层次分析女巫组,包括单个信息,社会关系,和恶意的活动。我们的主要观察是:1)在女巫组的用户信息通常是不完全的并且在差的质量;2)女巫组在连接结构,增加节点的包括的bursty行动,和缺乏非单条mergings的一个单调的合并模式有特殊进化模式;3)几个女巫组与对方一起有强壮的关系并且填写女巫社区,和这些社区盖子很多用户和姿势伟人潜力威胁;4)一些女巫用户没在一些女巫组在登记以后被禁止直到很长时间。女巫组的特征能被利用在OSN改进安全机制对女巫攻击保卫。明确地,我们建议那OSN应该1)检查信息完全性和质量,2)从社区连接结构的动力学学习检测女巫组,3)监视女巫社区并且小心地检查他们阻止串通,并且4)检查甚至很长时间通常表现阻止潜在的恶意的行为的女巫组。
简介:AbstractGenomoviridae is a virus family belonging to circular replication associated protein encoding ssDNA (CRESS-DNA) viruses, which have diverse genomic architecture and are widely distributed among different ecosystems. In this study, we characterized 39 novel genomovirus genomes including 3 from wild egrets, 9 from wild cranes, as well as 27 from wild finches in three different types of cloacal swabs of wild bird sampled in the station of Xinqing bird ringing, Maoershan Nature Reserve in Heilongjiang Province, Changbai Mountain in Jilin Province, and Hangzhou Wetland Park in Zhejiang Province, China. Here, using a Rep sequence phylogeny-based analysis, we divided the 39 genomoviruses into 8 genera within the family Genomoviridae, including Gemycircularvirus (n =20), Gemykibivirus (n =3), Gemygorvirus (n =2), Gemyvongvirus (n =2), Gemykolovirus (n =3), Gemykrogvirus (n =6), Gemytondvirus (n=1), Gemyduguivirus (n=1) and one unclassified genomovirus. The 39 genomovirus genomes belong to 36 species (27 of which are new) based on the currently accepted genomovirus pairwise nucleotide sequence identity species demarcation threshold of 78%. Overall, the research enriches our knowledge of CRESS-DNA viral diversity in China and emphasizes the prevalence of genomoviruses in nature.
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简介:AbstractThe emergence of mobile Tigecycline-resistant tet(X3) and tet(X4) is believed to be a global threat to public health. Here, we investigated the prevalence of tet(X3) and tet(X4) in our metagenomic data of migratory birds. While tet (X4) was not identified in our samples, tet(X3) was found in two gut microbiomes of bird fecal samples, with 100% amino acid identity of sites 150–387. These results suggest that tet(X3) has been spreading into the environment for a long period of time and that there is an urgent need to control its further transmission.
简介:MicroRNAs(miRNAs)是非编码的小RNA,它响应关於生命、不能生活的压力起重要规章的作用。Dongxiang野米饭(Oryzarufipogon,DXWR)能在极端干旱环境幸存,但是它干旱抵抗的分子的机制大部分仍然是未知的。为了进一步探索miRNA,规章的机制在干旱抵抗包含了,我们用小RNA定序和生物信息学途径在DXWR识别了138新奇miRNAs,并且发现67新奇miRNAs的表示层次被干旱应力signicantly影响。总共,200候选人目标基因为干旱被预言并且注解压力应答的新奇miRNAs。基因本体论(去)小径建议了的基因和染色体(KEGG)的分析和京都百科全书大多数目标基因与新陈代谢有关。高展出的茎环量的即时PCR(qRT-PCR)结果与定序数据索引,哪个miRNA表示模式基于在现在的学习定序的小RNA是可靠的conrmed。同时,qRT-PCR验证了在几miRNAs和他们的目标基因之间的反的表示模式。这些结果将提高我们在DXWR响应干旱应力理解规章的机制miRNA,并且能为这个珍贵基因资源的保护和利用用作一本重要参考书。