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221.
222.
DENS: data center energy-efficient network-aware scheduling 总被引:1,自引:0,他引:1
In modern data centers, energy consumption accounts for a considerably large slice of operational expenses. The existing work in data center energy optimization is focusing only on job distribution between computing servers based on workload or thermal profiles. This paper underlines the role of communication fabric in data center energy consumption and presents a scheduling approach that combines energy efficiency and network awareness, named DENS. The DENS methodology balances the energy consumption of a data center, individual job performance, and traffic demands. The proposed approach optimizes the tradeoff between job consolidation (to minimize the amount of computing servers) and distribution of traffic patterns (to avoid hotspots in the data center network). 相似文献
223.
Kashif Bilal Samee U. Khan Sajjad A. Madani Khizar Hayat Majid I. Khan Nasro Min-Allah Joanna Kolodziej Lizhe Wang Sherali Zeadally Dan Chen 《Cluster computing》2013,16(3):575-589
The Information and Communication Technology sector is considered to be a major consumer of energy and has become an active participant in Green House Gas emissions. Lots of efforts have been devoted to make network infrastructure and network protocols power-aware and green. Among these efforts, Adaptive Link Rate (ALR) is one of the most widely discussed approaches. This survey highlights the most recent ALR approaches with a brief taxonomy and the state of the art. 相似文献
224.
Frédéric Pinel Bernabé Dorronsoro Johnatan E. Pecero Pascal Bouvry Samee U. Khan 《Cluster computing》2013,16(3):421-433
The sensitivity analysis of a Cellular Genetic Algorithm (CGA) with local search is used to design a new and faster heuristic for the problem of mapping independent tasks to a distributed system (such as a computer cluster or grid) in order to minimize makespan (the time when the last task finishes). The proposed heuristic improves the previously known Min-Min heuristic. Moreover, the heuristic finds mappings of similar quality to the original CGA but in a significantly reduced runtime (1,000 faster). The proposed heuristic is evaluated across twelve different classes of scheduling instances. In addition, a proof of the energy-efficiency of the algorithm is provided. This convergence study suggests how additional energy reduction can be achieved by inserting low power computing nodes to the distributed computer system. Simulation results show that this approach reduces both energy consumption and makespan. 相似文献
225.
226.
V. Ramana Gopavajhula K. Viswanatha Chaitanya P. Akbar Ali Khan Jilani P. Shaik P. Narasimha Reddy Mohammad Alanazi 《Genetics and molecular biology》2013,36(2):225-236
Superoxide dismutase (SOD, EC 1.15.1.1) is an important metal-containing antioxidant enzyme that provides the first line of defense against toxic superoxide radicals by catalyzing their dismutation to oxygen and hydrogen peroxide. SOD is classified into four metalloprotein isoforms, namely, Cu/Zn SOD, Mn SOD, Ni SOD and Fe SOD. The structural models of soybean SOD isoforms have not yet been solved. In this study, we describe structural models for soybean Cu/Zn SOD, Mn SOD and Fe SOD and provide insights into the molecular function of this metal-binding enzyme in improving tolerance to oxidative stress in plants. 相似文献
227.
Armen A. Ghazarian Megan A. Murphy Maria R. Khan Brit I. Saksvig Sean F. Altekruse 《PloS one》2013,8(11)
Purpose
To examine the associations between area-level socioeconomic attributes and stage of esophageal adenocarcinoma diagnoses in 16 SEER cancer registries during 2000-2007.Methods
Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable logistic regression models to assess the relationship between distant-stage esophageal adenocarcinoma and individual, census tract, and county-level attributes.Results
Among cases with data on birthplace, no significant association was seen between reported birth within versus outside the United States and distant-stage cancer (adjusted OR=1.02, 95% CI: 0.85-1.22). Living in an area with a higher percentage of residents born outside the United States than the national average was associated with distant-stage esophageal adenocarcinoma; census tract level: >11.8%, (OR=1.10, 95% CI:1.01–1.19), county level: >11.8%, (OR=1.14, 95% CI:1.05-1.24). No association was observed between median household income and distant-stage cancer at either census tract or county levels.Conclusion
The finding of greater odds of distant-stage esophageal adenocarcinoma among cases residing in SEER areas with higher proportion of non-U.S. Natives suggests local areas where esophageal cancer control efforts might be focused. Missing data at the individual level was a limitation of the present study. Furthermore, inconsistent associations with foreign birth at individual- versus area-levels cautions against using area-level attributes as proxies for case attributes. 相似文献228.
Mohd Sajid Khan Mohd Hassan Baig Saheem Ahmad Shapi Ahmad Siddiqui Ashwini Kumar Srivastava Kumar Venkatraman Srinivasan Irfan A. Ansari 《PloS one》2013,8(8)
Targeting papain family cysteine proteases is one of the novel strategies in the development of chemotherapy for a number of diseases. Novel cysteine protease inhibitors derived from 1-pyridylimidazo[1,5-a]pyridine representing pharmacologically important class of compounds are being reported here for the first time. The derivatives were initially designed and screened in silico by molecular docking studies against papain to explore the possible mode of action. The molecular interaction between the compounds and cysteine protease (papain) was found to be very similar to the interactions observed with the respective epoxide inhibitor (E-64c) of papain. Subsequently, compounds were synthesized to validate their efficacy in wet lab experiments. When characterized kinetically, these compounds show their Ki and IC50 values in the range of 13.75 to 99.30 µM and 13.40 to 96.50 µM, respectively. The thermodynamics studies suggest their binding with papain hydrophobically and entropically driven. These inhibitors also inhibit the growth of clinically important different types of Gram positive and Gram negative bacteria having MIC50 values in the range of 0.6–1.4 µg/ml. Based on Lipinski’s rule of Five, we also propose these compounds as potent antibacterial prodrugs. The most active antibacterial compound was found to be 1-(2-pyridyl)-3-(2-hydroxyphenyl)imidazo[1,5-a]pyridine (3a). 相似文献
229.
Sarah K. Oettl Jana Gerstmeier Shafaat Y. Khan Katja Wiechmann Julia Bauer Atanas G. Atanasov Clemens Malainer Ezzat M. Awad Pavel Uhrin Elke H. Heiss Birgit Waltenberger Daniel Remias Johannes M. Breuss Joel Boustie Verena M. Dirsch Hermann Stuppner Oliver Werz Judith M. Rollinger 《PloS one》2013,8(10)
In vitro screening of 17 Alpine lichen species for their inhibitory activity against 5-lipoxygenase, microsomal prostaglandin E2 synthase-1 and nuclear factor kappa B revealed Cetrelia monachorum (Zahlbr.) W.L. Culb. & C.F. Culb. As conceivable source for novel anti-inflammatory compounds. Phytochemical investigation of the ethanolic crude extract resulted in the isolation and identification of 11 constituents, belonging to depsides and derivatives of orsellinic acid, olivetolic acid and olivetol. The two depsides imbricaric acid (4) and perlatolic acid (5) approved dual inhibitory activities on microsomal prostaglandin E2 synthase-1 (IC50 = 1.9 and 0.4 µM, resp.) and on 5-lipoxygenase tested in a cell-based assay (IC50 = 5.3 and 1.8 µM, resp.) and on purified enzyme (IC50 = 3.5 and 0.4 µM, resp.). Additionally, these two main constituents quantified in the extract with 15.22% (4) and 9.10% (5) showed significant inhibition of tumor necrosis factor alpha-induced nuclear factor kappa B activation in luciferase reporter cells with IC50 values of 2.0 and 7.0 µM, respectively. In a murine in vivo model of inflammation, 5 impaired the inflammatory, thioglycollate-induced recruitment of leukocytes to the peritoneum. The potent inhibitory effects on the three identified targets attest 4 and 5 a pronounced multi-target anti-inflammatory profile which warrants further investigation on their pharmacokinetics and in vivo efficacy. 相似文献
230.
Zena A. Al-Mudaris Aman S. A. Majid Dan Ji Ban A. Al-Mudarris Shih-Hsun Chen Po-Huang Liang Hasnah Osman Shah Kamal Khan Jamal Din Amin M. S. Abdul Majid 《PloS one》2013,8(11)
Benzyl-o-vanillin and benzimidazole nucleus serve as important pharmacophore in drug discovery. The benzyl vanillin (2-(benzyloxy)-3-methoxybenzaldehyde) compound shows anti-proliferative activity in HL60 leukemia cancer cells and can effect cell cycle progression at G2/M phase. Its apoptosis activity was due to disruption of mitochondrial functioning. In this study, we have studied a series of compounds consisting of benzyl vanillin and benzimidazole structures. We hypothesize that by fusing these two structures we can produce compounds that have better anticancer activity with improved specificity particularly towards the leukemia cell line. Here we explored the anticancer activity of three compounds namely 2-(2-benzyloxy-3-methoxyphenyl)-1H-benzimidazole, 2MP, N-1-(2-benzyloxy-3-methoxybenzyl)-2-(2-benzyloxy-3-methoxyphenyl)-1H-benzimidazole, 2XP, and (R) and (S)-1-(2-benzyloxy-3-methoxyphenyl)-2, 2, 2-trichloroethyl benzenesulfonate, 3BS and compared their activity to 2-benzyloxy-3-methoxybenzaldehyde, (Bn1), the parent compound. 2XP and 3BS induces cell death of U937 leukemic cell line through DNA fragmentation that lead to the intrinsic caspase 9 activation. DNA binding study primarily by the equilibrium binding titration assay followed by the Viscosity study reveal the DNA binding through groove region with intrinsic binding constant 7.39 µM/bp and 6.86 µM/bp for 3BS and 2XP respectively. 2XP and 3BS showed strong DNA binding activity by the UV titration method with the computational drug modeling showed that both 2XP and 3BS failed to form any electrostatic linkages except via hydrophobic interaction through the minor groove region of the nucleic acid. The benzylvanillin alone (Bn1) has weak anticancer activity even after it was combined with the benzimidazole (2MP), but after addition of another benzylvanillin structure (2XP), stronger activity was observed. Also, the combination of benzylvanillin with benzenesulfonate (3BS) significantly improved the anticancer activity of Bn1. The present study provides a new insight of benzyl vanillin derivatives as potential anti-leukemic agent. 相似文献