Zika Virus Growth in Human Kidney Cells Is Restricted by an Elevated Glucose Level

Mosquito-borne Zika virus (ZIKV) became a real threat to human health due to the lack of vaccine and effective antiviral treatment. The virus has recently been responsible for a global outbreak leading to millions of infected cases. ZIKV complications were highlighted in adults with Guillain–Barré syndrome and in newborns with increasing numbers of congenital disorders ranging from mild developmental delays to fatal conditions. The ability of ZIKV to establish a long-term infection in diverse organs including the kidneys has been recently documented but the consequences of such a viral infection are still debated. Our study aimed to determine whether the efficiency of ZIKV growth in kidney cells relates to glucose concentration. Human kidney HK-2 cells were infected with different ZIKV strains in presence of normal and high glucose concentrations. Virological assays showed a decrease in viral replication without modifying entry steps (viral binding, internalization, fusion) under high glucose conditions. This decrease replication was associated with a lower virus progeny and increased cell viability when compared to ZIKV-infected HK-2 cells in normal glucose concentration. In conclusion, we showed for the first time that an elevated glucose level influences ZIKV replication level with an effect on kidney cell survival.     

Silver(I)-Ion-Mediated Cytosine-Containing Base Pairs: Metal Ion Specificity for Duplex Stabilization and Susceptibility toward DNA Polymerases

Spectroscopic characterization of Ag^I-ion-mediated C-Ag^I-A and C-Ag^I-T base pairs found in primer extension reactions catalyzed by DNA polymerases was conducted. UV melting experiments revealed that C-A and C-T mismatched base pairs in oligodeoxynucleotide duplexes are specifically stabilized by Ag^I ions in 1:1 stoichiometry in the same manner as a C-C mismatched base pair. Although the stability of the mismatched base pairs in the absence of Ag^I ions is in the order C-A≈C-T>C-C, the stabilizing effect of Ag^I ions follows the order C-C>C-A≈C-T. However, the comparative susceptibility of dNTPs to Ag^I-mediated enzymatic incorporation into the site opposite templating C is dATP>dTTP≫dCTP, as reported. The net charge, as well as the size and/or shape complementarity of the metal-mediated base pairs, or the stabilities of mismatched base pairs in the absence of metal ions, would be more important than the stability of the metallo-base pairs in the replicating reaction catalyzed by DNA polymerases.     

无线传感器网络节点复制攻击和女巫攻击防御机制研究

在无线传感器网络(WSNs)中,节点复制攻击和女巫攻击可扰乱数据融合和阈值选举等网络操作.发起这两种攻击需先通过邻居发现认证过程.考虑到在WSNs中发起邻居认证是不频繁的,提出了一种基于单向密钥链的ID认证防御机制(OKCIDA),降低攻击者在任何时间段发起这两种攻击的可能性.然后基于椭圆曲线离散对数问题,构造对称参数,并组合OKCIDA和利用节点邻居关系,提出了一种无需位置的邻居认证协议(LFNA),以阻止复制节点和女巫节点成功加入网络.最后给出了安全性证明和分析,并在安全和开销方面将LFNA与已有典型防御方案进行了比较,结果表明该方案具有一定的优势.     

针对拷贝因子的云存储负载均衡技术

为了解决当前云存储架构中分布式文件系统的负载均衡问题,在研究分析了各种不同的负载均衡算法以后,从文件的拷贝因子这一角度,提出了一种以自动化调整拷贝因子作为系统负载均衡策略的算法。该方法能明显提高云存储系统的吞吐率,减少客户端平均访问时间,从而能有效增加客户满意度。为了验证该方法的可行性与实际效果,对运行在Linux的开源版本opensuse之上的云存储系统Quantcast File System的文件拷贝因子模块进行了修改,实验结果显示用拷贝因子作为云存储环境负载均衡算法是有效的。     

NEBS GR-63-CORE抗震试验及其控制策略研究

对通信设备抗震试验方法进行了讨论,重点研究了NEBS GR-63-CORE抗震试验方法。针对抗震试验中地震模拟振动台频宽不够及存在非线性因素影响的问题,设计了地震模拟振动台三参量伺服控制算法,有效拓展了试验系统的频宽,提高试验系统的动态响应范围;并提出一种基于频域的驱动信号修正迭代算法,通过在线迭代修正驱动信号,补偿试验系统中非线性因素对系统的影响。NEBS GR-63-CORE抗震试验表明,基于三参量控制算法及驱动信号修正迭代算法的地震模拟振动台控制策略,能够实现高精度的地震波形复现试验。     

Invited review: Reproducible research from noisy data: Revisiting key statistical principles for the animal sciences

Reproducible results define the very core of scientific integrity in modern research. Yet, legitimate concerns have been raised about the reproducibility of research findings, with important implications for the advancement of science and for public support. With statistical practice increasingly becoming an essential component of research efforts across the sciences, this review article highlights the compelling role of statistics in ensuring that research findings in the animal sciences are reproducible—in other words, able to withstand close interrogation and independent validation. Statistics set a formal framework and a practical toolbox that, when properly implemented, can recover signal from noisy data. Yet, misconceptions and misuse of statistics are recognized as top contributing factors to the reproducibility crisis. In this article, we revisit foundational statistical concepts relevant to reproducible research in the context of the animal sciences, raise awareness on common statistical misuse undermining it, and outline recommendations for statistical practice. Specifically, we emphasize a keen understanding of the data generation process throughout the research endeavor, from thoughtful experimental design and randomization, through rigorous data analysis and inference, to careful wording in communicating research results to peer scientists and society in general. We provide a detailed discussion of core concepts in experimental design, including data architecture, experimental replication, and subsampling, and elaborate on practical implications for proper elicitation of the scope of reach of research findings. For data analysis, we emphasize proper implementation of mixed models, in terms of both distributional assumptions and specification of fixed and random effects to explicitly recognize multilevel data architecture. This is critical to ensure that experimental error for treatments of interest is properly recognized and inference is correctly calibrated. Inferential misinterpretations associated with use of P-values, both significant and not, are clarified, and problems associated with error inflation due to multiple comparisons and selective reporting are illustrated. Overall, we advocate for a responsible practice of statistics in the animal sciences, with an emphasis on continuing quantitative education and interdisciplinary collaboration between animal scientists and statisticians to maximize reproducibility of research findings.     

Incorporating the Raft consensus protocol in containers managed by Kubernetes: an evaluation

Replication is a technique widely used to improve the reliability of applications. State machine replication is a special approach, where a set of computers are kept synchronised in the same state despite of failures that could occur in the system. The Raft algorithm can be used to implement a total order delivery protocol, delivering requests at the same order at all replicas, which is fundamental since in this approach all replicas must execute the same sequence of requests to present the same evolution in their states. Raft is easy to understand and implement, when compared to the Paxos algorithm. On the other hand, virtualisation can be seen as a technique that helps the development of reliable applications since it maintains each virtual machine (VM) isolated from the others. Virtualisation in data centres is changing from the traditional VMs to containers. In this context, this paper proposes KRaft, an incorporation of Raft in Kubernetes, a system that manages containers. After an evaluation of performance and resource consumption of KRaft, we found that it presents performance close to Raft executing on physical machines. Moreover, KRaft demands more network transmission while Raft executed in physical machines needs more processing power and memory.