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111.
Esmail Asyabi Azadeh Azhdari Mostafa Dehsangi Michel Gokan Khan Mohsen Sharifi Sayed Vahid Azhari 《Cluster computing》2016,19(2):567-583
Cloud computing environments (CCEs) are expected to deliver their services with qualities in service level agreements. On the other hand, they typically employ virtualization technology to consolidate multiple workloads on the same physical machine, thereby enhancing the overall utilization of physical resources. Most existing virtualization technologies are, however, unaware of their delivered quality of services (QoS). For example, the Xen hypervisor merely focuses on fair sharing of processor resources. We believe that CCEs have got married with traditional virtualization technologies without many traits in common. To bridge the gap between these two technologies, we have designed and implemented Kani, a QoS-aware hypervisor-level scheduler. Kani dynamically monitors the quality of delivered services to quantify the deviation between desired and delivered levels of QoS. Using this information, Kani determines how to allocate processor resources among running VMs so as to meet the expected QoS. Our evaluations of Kani scheduler prototype in Xen show that Kani outperforms the default Xen scheduler namely the Credit scheduler. For example, Kani reduces the average response time to requests to an Apache web server by up to \(93.6\,\%\); improves its throughput by up to \(97.9\,\%\); and mitigates the call setup time of an Asterisk media server by up to \(96.6\,\%\). 相似文献
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Photovoltaics: Toward a Low‐Cost Artificial Leaf: Driving Carbon‐Based and Bifunctional Catalyst Electrodes with Solution‐Processed Perovskite Photovoltaics (Adv. Energy Mater. 20/2016)
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114.
In order to study bio fertilizers and zinc effects on some physiological parameters of triticale under a water-limitation condition, a factorial experiment was conducted based on randomized complete block design with three replications in 2014 and 2015. Experimental factors consisted of three irrigation treatments [normal irrigation (W0); moderate water limitation (W1) and severe water limitation (W2)]; four bio fertilizers’ levels [(no bio fertilizer (F0), application of mycorrhiza (F1), plant-growth-promoting rhizobacteria (PGPR) (F2) and both application PGPR and mycorrhiza (F3)] and four nano zinc oxide levels [(without nano zinc oxide (Zn0) as control, application of 0.3 (Zn1), 0.6 (Zn2) and 0.9 (Zn3) g?L?1)]. Results showed that water limitation decreased chlorophyll content, relative water content, stomatal conductance, quantum yield and grain yield of triticale, whereas electrical conductivity and the activity of catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7) and polyphenol oxidase (PPO, EC 1.14.18.1) enzymes were increased. Inoculation of plants with bio fertilizers and zinc application improved these traits (except electrical conductivity) under water-limitation condition as well as normal irrigation. Based on the results, it was concluded that bio fertilizers and nano zinc oxide application can be recommended for profitable triticale production under water-limitation condition. 相似文献
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The control of cell proliferation involves the complex interaction between growth factors and growth inhibitors. We have examined this interaction with the mitogen epidermal growth factor (EGF) and a recently purified 18 kD, pI 3, sialoglycopeptide that reversibly inhibits cellular metabolism of a variety of cells. The sialoglycopeptide was a very potent inhibitor of EGF action; 0.22 nM of the inhibitor completely blocked the mitogenic effect of 1.60 nM of EGF. The sialoglycopeptide, however, did not affect the binding of EGF to 3T3 cells. Neither the mixed affinities (0.11-1.9 nM) of binding nor the total number of receptors (50,000 receptors/cell) for EGF were altered by the addition of the sialoglycopeptide. In addition, competitive binding experiments demonstrated the specificity of inhibitor binding to 3T3 cells and also showed that EGF and the sialoglycopeptide did not share the same receptor, suggesting that the inhibitor blocked EGF action at a postreceptor, intracellular event in the signal cascade. We further demonstrated that the sialoglycopeptide had to be added within 2.5 hr after EGF to block effectively the stimulation of DNA synthesis by the growth factor, suggesting that the inhibitor blocked EGF stimulation at a relatively early step in the signal transduction mechanism. 相似文献
117.
Berenjian Atefeh Sharifi Seyed Davood Mohammadi-Sangcheshmeh Abdollah Ghazanfari Shokoufe 《Biological trace element research》2018,184(2):474-481
Biological Trace Element Research - Chromium (Cr), as an essential trace element, plays a critical role in carbohydrate, protein, and lipid metabolism in animals. It has been suggested that the... 相似文献
118.
Joseph L. Sevigny Lauren E. Kirouac William Kelley Thomas Jordan S. Ramsdell Kayla E. Lawlor Osman Sharifi Simarvir Grewal Christopher Baysdorfer Kenneth Curr Amanda A. Naimie Kazufusa Okamoto James A. Murray James M. Newcomb 《PloS one》2015,10(5)
The phylogenetic relationships among certain groups of gastropods have remained unresolved in recent studies, especially in the diverse subclass Opisthobranchia, where nudibranchs have been poorly represented. Here we present the complete mitochondrial genomes of Melibe leonina and Tritonia diomedea (more recently named T. tetraquetra), two nudibranchs from the unrepresented Cladobranchia group, and report on the resulting phylogenetic analyses. Both genomes coded for the typical thirteen protein-coding genes, twenty-two transfer RNAs, and two ribosomal RNAs seen in other species. The twelve-nucleotide deletion previously reported for the cytochrome oxidase 1 gene in several other Melibe species was further clarified as three separate deletion events. These deletions were not present in any opisthobranchs examined in our study, including the newly sequenced M. leonina or T. diomedea, suggesting that these previously reported deletions may represent more recently divergent taxa. Analysis of the secondary structures for all twenty-two tRNAs of both M. leonina and T. diomedea indicated truncated d arms for the two serine tRNAs, as seen in some other heterobranchs. In addition, the serine 1 tRNA in T. diomedea contained an anticodon not yet reported in any other gastropod. For phylogenetic analysis, we used the thirteen protein-coding genes from the mitochondrial genomes of M. leonina, T. diomedea, and seventy-one other gastropods. Phylogenetic analyses were performed for both the class Gastropoda and the subclass Opisthobranchia. Both Bayesian and maximum likelihood analyses resulted in similar tree topologies. In the Opisthobranchia, the five orders represented in our study were monophyletic (Anaspidea, Cephalaspidea, Notaspidea, Nudibranchia, Sacoglossa). In Gastropoda, two of the three traditional subclasses, Opisthobranchia and Pulmonata, were not monophyletic. In contrast, four of the more recently named gastropod clades (Vetigastropoda, Neritimorpha, Caenogastropoda, and Heterobranchia) were all monophyletic, and thus appear to be better classifications for this diverse group. 相似文献
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Azhir Elham Navimipour Nima Jafari Hosseinzadeh Mehdi Sharifi Arash Unal Mehmet Darwesh Aso 《Cluster computing》2022,25(3):2021-2036
Cluster Computing - In the distributed database systems, the relations needed by a query can be kept in several locations. This process significantly increases potential corresponding Query... 相似文献