4,996 research outputs found

    Multi-Objective Flexible Job Shop Scheduling Using Genetic Algorithms

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    Flexible Job Shop Scheduling is an important problem in the fields of combinatorial optimization and production management. This research addresses multi-objective flexible job shop scheduling problem with the objective of simultaneous minimization of: (1) makespan, (2) workload of the most loaded machine, and (3) total workload. A general-purpose, domain independent genetic algorithm implemented in a spreadsheet environment is proposed for the flexible job shop. Spreadsheet functions are used to develop the shop model. Performance of the proposed algorithm is compared with heuristic algorithms already reported in the literature. Simulation experiments demonstrated that the proposed methodology can achieve solutions that are comparable to previous approaches in terms of solution quality and computational time. Flexible job shop models presented herein are easily customizable to cater for different objective functions without changing the basic genetic algorithm routine or the spreadsheet model. Experimental analysis demonstrates the robustness, simplicity, and general-purpose nature of the proposed approach

    Evaluation of low-intensity laser radiation on stimulating the cholesterol degrading activity: Part I. Microorganisms isolated from cholesterol-rich materials

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    AbstractA survey was performed to isolate bacteria and fungi from cholesterol-rich sources including chicken liver, turkey giblets, salmon, lamb, egg yolk, beef brain and shrimps. A total of 34 bacterial and 22 fungal isolates were recovered from the tested sources. The highest count of isolates was recovered from the soil (12 isolates/g), followed by turkey giblets and egg yolk (8 isolates/g, for each). Out of 34 bacterial isolates, five induced the highest level in cholesterol degradation. The most potent bacterial isolate was recovered from turkey giblets and was identified as Streptomyces fradiae. In a trial to increase the cholesterol decomposing potentiality of S. fradiae, low intensity Nd-YAG laser irradiation was evaluated. The exposure of the chlorophyllin – photosensitized bacterium to 210mW Nd-YAG laser for 8min induced significant increase in cholesterol degrading activity reaching 73.8% as compared with 54.2% in the case of non-irradiated, non-photosensitized culture. Under the same conditions but using the reaction mixture containing cholesterol as a substrate and extracellular crude enzyme, the percent decomposition reached 53.7% for the irradiated culture as compared to 28.3% in the case of the control. Our data indicate the importance of the photosensitizer in enhancement of laser radiation to stimulate cholesterol decomposition of S. fradiae

    Performance of a local signalized intersection for handling traffic operation in Baghdad City

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    The inspection of the flexibility and performance of a local signalized intersection in managing traffic operation in Baghdad city is the main target of this study. Andalus intersection is one of the important local intersections in Bagdad city which recorded remarkable traffic congestion problem now a days and have been chosen in this study as a part of continuous studies due to its vital location. Smart Traffic Analysis (STA) software is used to give an aspect to the inefficient performance of the Andalus signalized intersection having three approached links and four exit legs while SYNCHRO software is used to simulate the data analysis and offer different alternative solutions to solve the congestion problem. From the obtained data analysis it has been found that the best suggested alteration for handling the current traffic volume of each studied intersection approach is the signalized intersection with optimum cycle time combined with the addition of two lanes, where the mean delay for the entire intersection can be reduced by approximately 26% by applying alteration No.1 while the mean delay for the entire intersection can be reduce approximately by 31% by applying alteration No.2. Furthermore, the queue length for the entire intersection can be reducing by approximately 6% and 17% for alteration No.1 and No.2 respectively

    Nfia Deletion in Myeloid Cells Blocks Expansion of Myeloid-Derived Suppressor Cells During Sepsis

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    Sepsis-induced immunosuppression increases the risk of chronic infection and reduces survival. Myeloid-derived suppressor cells (MDSCs) expand in the bone marrow and spleen during murine polymicrobial sepsis, contributing to immunosuppression. A better understanding of molecular controls of MDSC production is needed to identify treatment targets. We previously reported that miR-21 and miR-181b couple with transcription factor NFI-A to induce MDSCs during murine sepsis. Here, we expand upon these observations by showing that conditional deletion of the Nfia gene in the myeloid lineage precludes MDSC development. NFI-A-deficient Gr1+CD11b+ myeloid cells are not immunosuppressive and differentiate normally into macrophages and dendritic cells. In contrast, ectopically expressed NFI-A prevents differentiation of these immature Gr1+CD11b+ cells, while converting them into MDSCs. In addition, NFI-A-deficient Gr1+CD11b+ cells decreased, and cells transfected with NFI-A increase expression of miR-21 and miR181b. Our results support a myeloid cell loop in which NFI-A and miR-21 and miR-181b sustain Gr1+CD11b+ MDSC-dependent immunosuppression during sepsis

    HCV-induced miR146a Controls SOCS1/STAT3 and Cytokine Expression in Monocytes to Promote Regulatory T-cell Development

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    Host innate and adaptive immune responses must be tightly regulated by an intricate balance between positive and negative signals to ensure their appropriate onset and termination while fighting pathogens and avoiding autoimmunity; persistent pathogens may usurp these regulatory machineries to dampen host immune responses for their persistence in vivo. Here, we demonstrate that miR146a is up‐regulated in monocytes from hepatitis C virus (HCV )‐infected individuals compared to control subjects. Interestingly, miR146a expression in monocytes without HCV infection increased, whereas its level in monocytes with HCV infection decreased, following Toll‐like receptor (TLR ) stimulation. This miR146a induction by HCV infection and differential response to TLR stimulation were recapitulated in vitro in monocytes co‐cultured with hepatocytes with or without HCV infection. Importantly, inhibition of miR146a in monocytes from HCV ‐infected patients led to a decrease in IL ‐23, IL ‐10 and TGF ‐ÎČ expressions through the induction of suppressor of cytokine signalling 1 (SOCS 1) and the inhibition of signal transducer and activator transcription 3 (STAT 3), and this subsequently resulted in a decrease in regulatory T cells (Tregs) accumulated during HCV infection. These results suggest that miR146a may regulate SOCS 1/STAT 3 and cytokine signalling in monocytes, directing T‐cell differentiation and balancing immune clearance and immune injury during chronic viral infection

    Exploring the molecular mechanisms of MSC-derived exosomes in Alzheimer's disease : Autophagy, insulin and the PI3K/Akt/mTOR signaling pathway

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    The authors thank you for acknowledging technical and financial support from the Ministry of Education and the University of Hafr Al Batin, Saudi Arabia. The authors gratefully acknowledge all mothers’ volunteers in the community around the Faculty of Agriculture, Benha University, for their cooperationPeer reviewe
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