2,418 research outputs found

    FRTRUST: a fuzzy reputation based model for trust management in semantic P2P grids

    Full text link
    Grid and peer-to-peer (P2P) networks are two ideal technologies for file sharing. A P2P grid is a special case of grid networks in which P2P communications are used for communication between nodes and trust management. Use of this technology allows creation of a network with greater distribution and scalability. Semantic grids have appeared as an expansion of grid networks in which rich resource metadata are revealed and clearly handled. In a semantic P2P grid, nodes are clustered into different groups based on the semantic similarities between their services. This paper proposes a reputation model for trust management in a semantic P2P Grid. We use fuzzy theory, in a trust overlay network named FR TRUST that models the network structure and the storage of reputation information. In fact we present a reputation collection and computation system for semantic P2P Grids. The system uses fuzzy theory to compute a peer trust level, which can be either: Low, Medium, or High. Our experimental results demonstrate that FR TRUST combines low (and therefore desirable) a good computational complexity with high ranking accuracy.Comment: 12 Pages, 10 Figures, 3 Tables, InderScience, International Journal of Grid and Utility Computin

    Tau Kinetics in Alzheimer\u27s Disease

    Get PDF
    The Cytoskeletal Protein Tau is Implicated in the Pathogenesis of Alzheimer\u27s Disease Which is Characterized by Intra-Neuronal Neurofibrillary Tangles Containing Abnormally Phosphorylated Insoluble Tau. Levels of Soluble Tau Are Elevated in the Brain, the CSF, and the Plasma of Patients with Alzheimer\u27s Disease. to Better Understand the Causes of These Elevated Levels of Tau, We Propose a Three-Compartment Kinetic Model (Brain, CSF, and Plasma). the Model Assumes that the Synthesis of Tau Follows Zero-Order Kinetics (Uncorrelated with Compartmental Tau Levels) and that the Release, Absorption, and Clearance of Tau is Governed by First-Order Kinetics (Linearly Related to Compartmental Tau Levels). Tau that is Synthesized in the Brain Compartment Can Be Released into the Interstitial Fluid, Catabolized, or Retained in Neurofibrillary Tangles. Tau Released into the Interstitial Fluid Can Mix with the CSF and Eventually Drain to the Plasma Compartment. However, Losses of Tau in the Drainage Pathways May Be Significant. the Kinetic Model Estimates Half-Life of Tau in Each Compartment (552 H in the Brain, 9.9 H in the CSF, and 10 H in the Plasma). the Kinetic Model Predicts that an Increase in the Neuronal Tau Synthesis Rate or a Decrease in Tau Catabolism Rate Best Accounts for Observed Increases in Tau Levels in the Brain, CSF, and Plasma Found in Alzheimer\u27s Disease. Furthermore, the Model Predicts that Increases in Brain Half-Life of Tau in Alzheimer\u27s Disease Should Be Attributed to Decreased Tau Catabolism and Not to Increased Tau Synthesis. Most Clearance of Tau in the Neuron Occurs through Catabolism Rather Than Release to the CSF Compartment. Additional Experimental Data Would Make Ascertainment of the Model Parameters More Precise

    Chromatin Structure in Cell Differentiation, Aging and Cancer

    Get PDF
    Chromatin is the structure that the eukaryotic genome is packaged into, allowing over a metre of DNA to fit into the small volume of the nucleus. It is composed of DNA and proteins, most of which are histones. This DNA-protein complex is the template for a number of essential cell processes including transcription and replication. The basic structural unit of chromatin is the nucleosome. Nucleosomes comprise around 146 base pairs of DNA wrapped in a left-handed superhelix 1.7 times around a core histone octamer. This 11nm fibre is often referred to as ‘beads on a string’. Chromatin assembly involves wrapping of DNA around histone octameres producing repetitive nucleosomal array followed by folding of chromatin fibre into solenoid-like structure and deposition of non-histone proteins

    Gold Market Analyzer using Selection based Algorithm

    Full text link
    Gold is the most important and valuable element right from its discovery. It is the most significant element at present and also the most valuable asset to. In the present market scenario the investors use gold as the security for their shares investment. During International trade all the countries use gold as their main mode of transaction. It is seen that all the currencies accepted by the International market are having the gold as the backup for their economy. The prices of gold are rising day by day continuously. As we see in the history of gold market the present prices of gold are much high as compare to the past values and that's why the gold market has attracted the most attention. The paper focus on the continuous changing in the gold rates, investment policies depend on the forecasting of trends in gold which will help the data mining companies to minimize the risk The description of the future situation on the basis of present trends is just not limited to the forecasting the prices. The knowledge discovers by the data mining techniques is gathered from the different gold related websites and also from the jewellers database. It is much more important for the ornaments making companies to know the demand and the requirements for the ornaments during the unstable (uncertain) market conditions. For the classification purpose the maid and sale database was gathered from the nearest jewellery shops of the past 5 years. The prediction is done after complete analysis of the gathered data set. With this the paper concentrate on making the information available about the government and private schemes related to gold market on one place. The paper proposes the system that gives the total access to the registered user and limited access to the unregistered user to get the required information of gold. The latest updates are provided to the registered user by sending mail or text message when the user was offline

    Efficacy of HIV/STI behavioral interventions for heterosexual African American men in the United States: a meta-analysis

    Get PDF
    This meta-analysis estimates the overall efficacy of HIV prevention interventions to reduce HIV sexual risk behaviors and sexually transmitted infections (STIs) among heterosexual African American men. A comprehensive search of the literature published during 1988–2008 yielded 44 relevant studies. Interventions significantly reduced HIV sexual risk behaviors and STIs. The stratified analysis for HIV sexual risk behaviors indicated that interventions were efficacious for studies specifically targeting African American men and men with incarceration history. In addition, interventions that had provision/referral of medical services, male facilitators, shorter follow-up periods, or emphasized the importance of protecting family and significant others were associated with reductions in HIV sexual risk behaviors. Meta-regression analyses indicated that the most robust intervention component is the provision/referral of medical services. Findings indicate that HIV interventions for heterosexual African American men might be more efficacious if they incorporated a range of health care services rather than HIV/STI-related services alone
    • …
    corecore