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861.
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Data centers, clusters, and grids have historically supported High-Performance Computing (HPC) applications. Due to the high capital and operational expenditures associated with such infrastructures, we have witnessed consistent efforts to run HPC applications in the cloud in the recent past. The potential advantages of this shift include higher scalability and lower costs. If, on the one hand, app instantiation—through customized Virtual Machines (VMs)—is a well-solved issue, on the other, the network still represents a significant bottleneck. When switching HPC applications to be executed on the cloud, we lose control of where VMs will be positioned and of the paths that will be traversed for processes to communicate with one another. To bridge this gap, we present Janus, a framework for dynamic, just-in-time path provisioning in cloud infrastructures. By leveraging emerging software-defined networking principles, the framework allows for an HPC application, once deployed, to have interprocess communication paths configured upon usage based on least-used network links (instead of resorting to shortest, pre-computed paths). Janus is fully configurable to cope with different operating parameters and communication strategies, providing a rich ecosystem for application execution speed up. Through an extensive experimental evaluation, we provide evidence that the proposed framework can lead to significant gains regarding runtime. Moreover, we show what one can expect in terms of system overheads, providing essential insights on how better benefiting from Janus.

  相似文献   
864.
A plant’s associated biota plays an integral role in its metabolism, nutrient uptake, stress tolerance, pathogen resistance and other physiological processes. Although a virome is an integral part of the phytobiome, a major contradiction exists between the holobiont approach and the practical need to eradicate pathogens from agricultural crops. In this review, we discuss grapevine virus control, but the issue is also relevant for numerous other crops, including potato, cassava, citrus, cacao and other species. Grapevine diseases, especially viral infections, cause main crop losses. Methods have been developed to eliminate viruses and other microorganisms from plant material, but elimination of viruses from plant material does not guarantee protection from future reinfection. Elimination of viral particles in plant material could create genetic drift, leading in turn to an increase in the occurrence of pathogenic strains of viruses. A possible solution may be a combination of virus elimination and plant propagation in tissue culture with in vitro vaccination. In this context, possible strategies to control viral infections include application of plant resistance inducers, cross protection and vaccination using siRNA, dsRNA and viral replicons during plant ‘cleaning’ and in vitro propagation. The experience and knowledge accumulated in human immunization can help plant scientists to develop and employ new methods of protection, leading to more sustainable and healthier crop production.  相似文献   
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BioControl - Blackberry (Rubus glaucus Benth.) is affected by several diseases, such as grey mould (Botrytis cinerea Pers.), downy mildew (Peronospora sp.) and anthracnose (Colletotrichum sp.),...  相似文献   
867.
BioControl - Supplemental food application to crops as a resource for generalist predators has shown utility for promoting their establishment and persistence leading to enhanced biological control...  相似文献   
868.
Yatsuk  A. A.  Shestakov  L. S. 《Biology Bulletin》2022,49(5):564-568
Biology Bulletin - This paper discusses vibration communication in representatives of the genus Meromyza. The frequency range of vibration signals of Meromyza saltatrix (L., 1761) females is 229 to...  相似文献   
869.
Plasma Physics Reports - Decay of plasma excited by injection of a quasi-stationary beam of high-energy electrons into argon filling a cylindrical reaction chamber is studied experimentally. Based...  相似文献   
870.
Kassem  A. I.  Kopnin  S. I.  Popel  S. I.  Zelenyi  L. M. 《Plasma Physics Reports》2022,48(4):361-366
Plasma Physics Reports - Abstract—Modified Kadomtsev–Petviashvili equation describing nonlinear dynamics of nearly one-dimensional wave structures in dusty plasma above illuminated part...  相似文献   
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