排序方式: 共有271条查询结果,搜索用时 15 毫秒
51.
M. M. Tajiki B. Akbari M. Shojafar S. H. Ghasemi M. L. Barazandeh N. Mokari L. Chiaraviglio M. Zink 《Cluster computing》2018,21(4):1881-1897
The proliferation of cloud data center applications and network function virtualization (NFV) boosts dynamic and QoS dependent traffic into the data centers network. Currently, lots of network routing protocols are requirement agnostic, while other QoS-aware protocols are computationally complex and inefficient for small flows. In this paper, a computationally efficient congestion avoidance scheme, called CECT, for software-defined cloud data centers is proposed. The proposed algorithm, CECT, not only minimizes network congestion but also reallocates the resources based on the flow requirements. To this end, we use a routing architecture to reconfigure the network resources triggered by two events: (1) the elapsing of a predefined time interval, or, (2) the occurrence of congestion. Moreover, a forwarding table entries compression technique is used to reduce the computational complexity of CECT. In this way, we mathematically formulate an optimization problem and define a genetic algorithm to solve the proposed optimization problem. We test the proposed algorithm on real-world network traffic. Our results show that CECT is computationally fast and the solution is feasible in all cases. In order to evaluate our algorithm in term of throughput, CECT is compared with ECMP (where the shortest path algorithm is used as the cost function). Simulation results confirm that the throughput obtained by running CECT is improved up to 3× compared to ECMP while packet loss is decreased up to 2×. 相似文献
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Nahid Shahabadi Alireza Akbari Mina Jamshidbeigi Reza Khodarahmi 《Nucleosides, nucleotides & nucleic acids》2016,35(6):315-333
A copper complex of carmoisine dye; [Cu(carmoisine)2(H2O)2]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 104 M?1) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer. 相似文献
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Fatemeh Akbari Abbas Ali Zamani Mohammad Hossein Hosseinpour 《Archives Of Phytopathology And Plant Protection》2013,46(19):2364-2368
In this study, parasitism rate, development, emergence rate, sex ratio and adult longevity of Trichogramma brassicae, Trichogramma pintoi and Trichogramma embryophagum were investigated on eggs of diamondback moth, Plutella xylostella (Lep. Plutellidae) under controlled conditions. At the beginning of the experiments, 50 eggs of P. xylostella were exposed to parasitism of female wasps of different Trichogramma species. The eggs were replaced daily for three days and exposed eggs were kept in discrete glass vials. According to the obtained results, parasitism rates of T. brassicae, T. pintoi and T. embryophagum were 79.10, 93.90 and 86.10%, respectively. The adult emergence rates showed significant differences among various parasitoid species and were 93.72, 88.16 and 89.93% for T. brassicae, T. pintoi and T. embryophagum, respectively. No significant variations were observed among sex ratio values of the three parasitoid species. Consequently, results of present study suggested that T. pintoi could be more efficient for biocontrol of P. xylostella. 相似文献
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Angela M. Keuling Kathleen E. A. Felton Arabesque A. M. Parker Majid Akbari Susan E. Andrew Victor A. Tron 《PloS one》2009,4(8)
Background
Malignant melanoma is resistant to almost all conventional forms of chemotherapy. Recent evidence suggests that anti-apoptotic proteins of the Bcl-2 family are overexpressed in melanoma and may contribute to melanoma''s striking resistance to apoptosis. ABT-737, a small-molecule inhibitor of Bcl-2, Bcl-xl and Bcl-w, has demonstrated efficacy in several forms of leukemia, lymphoma as well as solid tumors. However, overexpression of Mcl-1, a frequent observance in melanoma, is known to confer ABT-737 resistance.Methodology/Principal Findings
Here we report that knockdown of Mcl-1 greatly reduces cell viability in combination with ABT-737 in six different melanoma cell lines. We demonstrate that the cytotoxic effect of this combination treatment is due to apoptotic cell death involving not only caspase-9 activation but also activation of caspase-8, caspase-10 and Bid, which are normally associated with the extrinsic pathway of apoptosis. Caspase-8 (and caspase-10) activation is abrogated by inhibition of caspase-9 but not by inhibitors of the death receptor pathways. Furthermore, while caspase-8/-10 activity is required for the full induction of cell death with treatment, the death receptor pathways are not. Finally, we demonstrate that basal levels of caspase-8 and Bid correlate with treatment sensitivity.Conclusions/Significance
Our findings suggest that the combination of ABT-737 and Mcl-1 knockdown represents a promising, new treatment strategy for malignant melanoma. We also report a death receptor-independent role for extrinsic pathway proteins in treatment response and suggest that caspase-8 and Bid may represent potential markers of treatment sensitivity. 相似文献60.
Reza Amani Somaye Saeidi Zahra Nazari Sorour Nematpour 《Biological trace element research》2010,137(2):150-158
It has been suggested that mood disorders and depressive status may be accompanied by lowered zinc status in the body, and
adequate consumption of zinc increases a general perceived well-being. The main objective of this study was to assess the
correlation between serum zinc concentrations and dietary zinc intakes with depression scores in university female students.
In the first phase, Beck's depression questionnaire was applied in a random sampling of 308 selected 20–25-year-old female
students (one third of total students in Ahvaz Jondi-Shapour University of Medical Sciences Golestan dormitories) to assess
the major depressive disorder (MDD) scales. Then, in the second phase, 23 students who identified as having moderate and severe
depression were selected as the case group, and 23 healthy age matched were chosen as the controls. Each of them completed
a 12-item semiquantitative food frequency questionnaire containing the main food sources of zinc in the usual dietary patterns
and also a 24-h food recall questionnaire to assure the daily zinc intakes. Daily zinc intakes were obtained by multiplying
each portion size by its zinc content using food tables. A 5-ml blood sample was taken for further serum zinc status using
flame atomic absorption spectrophotometry technique. Pearson's r was used to show the correlation between quantitative variables. Both daily zinc intake and serum zinc concentrations of
MDD group were about two thirds of healthy index (p < 0.01). Depressed individuals used to eat lower servings of red meats and chicken as the main food sources of zinc in students'
usual diets (p < 0.001). Consumption of other foods as the sources of zinc was not significantly different in two groups. A linear significant
correlation between dietary zinc intakes and its serum levels was seen in samples (r = 0.62; p < 0.001) and MDD students (r = 0.55; p < 0.001). There was a linear inverse correlation between Beck questionnaire scores and serum zinc concentrations in all of
the investigated students(r = -0.65; p < 0.001) and MDD girls (r = −0.71; p < 0.001). Beck questionnaire scores and diatary zinc intakes were also inversly correlated (r = −0.58; p < 0.001). However, no statistical correlation was seen between these two variables in MDD cases. In depressed female students,
dietary zinc intake is correlated to its serum concentrations; however, the serum zinc levels are inversely correlated to
depression scales. Consumption of the main dietary sources of zinc such as red meats and chicken should be encouraged in young
depressed girls. 相似文献