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41.
The demand for cloud computing is increasing dramatically due to the high computational requirements of business, social, web and scientific applications. Nowadays, applications and services are hosted on the cloud in order to reduce the costs of hardware, software and maintenance. To satisfy this high demand, the number of large-scale data centers has increased, which consumes a high volume of electrical power, has a negative impact on the environment, and comes with high operational costs. In this paper, we discuss many ongoing or implemented energy aware resource allocation techniques for cloud environments. We also present a comprehensive review on the different energy aware resource allocation and selection algorithms for virtual machines in the cloud. Finally, we come up with further research issues and challenges for future cloud environments. 相似文献
42.
Fahd Al-Mulla Mahera Abdulrahman Govindarajulu Varadharaj Nadeem Akhter Jehoram T Anim 《The journal of histochemistry and cytochemistry》2005,53(5):621-629
Breast cancer is a major cause of cancer-related mortality in women. There are major discrepancies concerning the usefulness of various antibodies in detecting breast cancer susceptibility gene 1 (BRCA1) protein and its subcellular localization. The aim of the present study was to determine the specificity and sensitivity of immunohistochemistry (IHC) as a screening method for demonstrating BRCA1 expression. BRCA1 gene expression in archival paraffin-embedded breast cancer tissues was studied simultaneously at the protein and mRNA levels, and the two findings were compared. Forty-eight archival paraffin-embedded breast cancer tissues were studied for BRCA1 gene expression at protein level by IHC using four different antibodies against different BRCA1 epitopes and at mRNA level using real-time RT-PCR. BRCA1 mRNA expression was reduced or absent in 79% of the samples, and this finding correlated significantly with loss of BRCA1 protein expression in 83% of breast cancer tissues using one BRCA1 antibody studied (AB-1, against N-terminus epitope). The specificity of this antibody was 91.3%, and its sensitivity was 66.6%. There was no significant correlation between BRCA1 mRNA and protein expression as demonstrated by the remaining three antibodies. Antibody 8F7 had the highest sensitivity of 100%, but its specificity was 30.4% if mRNA levels were considered as the reference standard. 相似文献
43.
Kuruvilla SJ Fox SD Cullen DM Akhter MP 《Journal of musculoskeletal & neuronal interactions》2008,8(1):71-78
Over 25 million Americans suffer from osteoporosis. Bone size and strength depends both upon the level of adaptation due to physical activity (applied load), and genetics. We hypothesized that bone adaptation to loads differs among mice breeds and bone sites. Forty-five adult female mice from three inbred strains (C57BL/6 [B6], C3H/HeJ [C3], and DBA/2J [D2]) were loaded at the right tibia and ulna in vivo with non-invasive loading devices. Each loading session consisted of 99 cycles at a force range that induced approximately 2000 microstrain (microepsilon) at the mid-shaft of the tibia (2.5 to 3.5 N force) and ulna (1.5 to 2 N force). The right and left ulnae and tibiae were collected and processed using protocols for histological undecalcified cortical bone slides. Standard histomorphometry techniques were used to quantify new bone formation. The histomorphometric variables include percentage mineralizing surface (%MS), mineral apposition rate (MAR), and bone formation rate (BFR). Net loading response [right-left limb] was compared between different breeds at tibial and ulnar sites using two-way ANOVA with repeated measures (p<0.05). Significant site differences in bone adaptation response were present within each breed (p<0.005). In all the three breeds, the tibiae showed greater percentage MS, MAR and BFR than the ulna at similar in vivo load or mechanical stimulus (strain). These data suggest that the bone formation due to loading is greater in the tibiae than the ulnae. Although, no significant breed-related differences were found in response to loading, the data show greater trends in tibial bone response in B6 mice as compared to D2 and C3 mice. Our data indicate that there are site-specific skeletal differences in bone adaptation response to similar mechanical stimulus. 相似文献
44.
Bosse TD Larson DP Wagner R Hutchinson DK Rockway TW Kati WM Liu Y Masse S Middleton T Mo H Montgomery D Jiang W Koev G Kempf DJ Molla A 《Bioorganic & medicinal chemistry letters》2008,18(2):568-570
A series of gem-dialkyl naphthalenone derivatives with varied alkyl substitutions were synthesized and evaluated according to their structure-activity relationship. This investigation led to the discovery of potent inhibitors of the hepatitis C virus at low nanomolar concentrations in both enzymatic and cell-based HCV genotype 1a assays. 相似文献
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47.
Human gene 3 (H3) relaxin is the most recently discovered member of the relaxin peptide family and can potentially bind all of the defined relaxin family peptide receptors (RXFP1-4). While its effects as a neuromodulator are being increasingly studied through its primary receptor, RXFP3, its actions via other RXFPs are poorly understood. Hence, we specifically determined the antifibrotic effects and mechanisms of action of H3 relaxin via the RXFP1 receptor using primary rat ventricular fibroblasts in vitro, which naturally express RXFP1, but not RXFP3, and a mouse model of fibrotic cardiomyopathy in vivo. Transforming growth factor β1 (TGF-β1) administration to ventricular fibroblasts significantly increased Smad2 phosphorylation, myofibroblast differentiation, and collagen deposition (all p < 0.05 vs untreated controls), while having no marked effect on matrix metalloproteinase (MMP) 9, MMP-13, tissue inhibitor of metalloproteinase (TIMP) 1, or TIMP-2 expression over 72 h. H3 relaxin (at 100 and 250 ng/mL) almost completely abrogated the TGF-β1-stimulated collagen deposition over 72 h, and its effects at 100 ng/mL were equivalent to that of the same dose of H2 relaxin. Furthermore, H3 relaxin (100 ng/mL) significantly inhibited TGF-β1-stimulated cardiac myofibroblast differentiation and TIMP-1 and TIMP-2 expression to an equivalent extent as H2 relaxin (100 ng/mL), while also inhibiting Smad2 phosphorylation to approximately half the extent of H2 relaxin (all p < 0.05 vs TGF-β1). Lower doses of H3 (50 ng/mL) and H2 (50 ng/mL) relaxin additively inhibited TGF-β1-stimulated collagen deposition in vitro, while H3 relaxin was also found to reverse left ventricular collagen overexpression in the model of fibrotic cardiomyopathy in vivo. These combined findings demonstrate that H3 relaxin exerts antifibrotic actions via RXFP1 and may enhance the collagen-inhibitory effects of H2 relaxin. 相似文献
48.
Rapson AC Hossain MA Wade JD Nice EC Smith TA Clayton AH Gee ML 《Biophysical journal》2011,(5):1353-1361
The interaction of a melittin mutant with a 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC)-supported lipid bilayer was studied with the use of time-resolved evanescent wave-induced fluorescence spectroscopy (TREWIFS) and evanescent wave-induced time-resolved fluorescence anisotropy measurements (EW-TRAMs). The mutant peptide was labeled at position K14 with AlexaFluor 430 and retained the lytic activity characteristic of native melittin. The fluorescence decay kinetics of the conjugate was found to be biexponential with a short-lived component, τ1, due to photoinduced electron transfer between AlexaFluor 430 and proximal side chains within or between the peptides. The longer-lived component, τ2, was sensitive to the polarity of the microenvironment at or near the K14 position of the peptide. Upon interaction with a DPPC-supported bilayer, the proportional contribution of τ1 increased, indicating a conformational change of the peptide. The values of τ1 and τ2 indicate that the AlexaFluor 430 probe experienced an environment with an equivalent polarity no less than that of methanol. EW-TRAMs data from the melittin mutant revealed hindered rotational motions of the AlexaFluor 430 probe both in the plane and perpendicular to the plane of the supported lipid bilayer. The data indicate a highly ordered and polar environment near the center of the melittin helix consistent with the formation of a toroidal pore. 相似文献
49.
Naseem Akhter Md. Salman Akhtar Md. Margoob Ahmad Shafiul Haque Sarah Siddiqui Syed Ikramul Hasan Nootan K. Shukla Syed Akhtar Husain 《Molecular biology reports》2014,41(5):2999-3007
p21 gene located at chromosome 6p21.2 is a possible tumour suppressor gene involved in the pathogenesis of breast cancer. Both genetic and epigenetic alterations in p21 have been implicated in breast carcinoma. In the present study, our main aim was to study the impact of these two kinds of alterations of p21 gene in Indian female breast cancer patients. A total of 150 female breast cancer patients of north India were screened by PCR-SSCP followed by direct sequencing and methylation specific PCR. Mutational screening of p21 gene revealed significant amount of mutations [32.66 % (49/150)] in exon 2, whereas p21 promoter was found hypermethylated in 42 of 150 (28 %) breast cancer patients in our population. The intriguing feature of the study was the G>T transition (GAG>TAG) at codon 107 and the A>C transition (AGC>CGC) at codon 146 possibly rendering p21 completely ineffective in its anti- proliferative activity. Our results suggest a significant association between the mutational and hypermethylation profile of p21 gene. Therefore, we show for the first time that the significant association of p21 mutation and hypermethylation leads to the complete inactivation of p21 gene in Indian female breast cancer patients. Complete silencing of the p21 gene seems to be the result not only of genetic alterations but also of epigenetic modification. 相似文献
50.
Raju K. Mandal Naseem Akhter Shafiul Haque Aditya K. Panda Rama D. Mittal Mohammed A. A. Alqumber 《PloS one》2014,9(8)