M-grid: Using Ubiquitous Web Technologies to create a Computational Grid

There are many potential users and uses for grid computing. However, the concept of sharing computing resources excites security concerns and, whilst being powerful and flexible, at least for novices, existing systems are complex to install and use. Together these represent a significant barrier to potential users who are interested to see what grid computing can do. This paper describes m-grid, a system for building a computational grid which can accept tasks from any user with access to a web browser and distribute them to almost any machine with access to the internet and manages to do this without the installation of additional software or interfering with existing security arrangements

Cloudbus Toolkit for Market-Oriented Cloud Computing

This keynote paper: (1) presents the 21st century vision of computing and identifies various IT paradigms promising to deliver computing as a utility; (2) defines the architecture for creating market-oriented Clouds and computing atmosphere by leveraging technologies such as virtual machines; (3) provides thoughts on market-based resource management strategies that encompass both customer-driven service management and computational risk management to sustain SLA-oriented resource allocation; (4) presents the work carried out as part of our new Cloud Computing initiative, called Cloudbus: (i) Aneka, a Platform as a Service software system containing SDK (Software Development Kit) for construction of Cloud applications and deployment on private or public Clouds, in addition to supporting market-oriented resource management; (ii) internetworking of Clouds for dynamic creation of federated computing environments for scaling of elastic applications; (iii) creation of 3rd party Cloud brokering services for building content delivery networks and e-Science applications and their deployment on capabilities of IaaS providers such as Amazon along with Grid mashups; (iv) CloudSim supporting modelling and simulation of Clouds for performance studies; (v) Energy Efficient Resource Allocation Mechanisms and Techniques for creation and management of Green Clouds; and (vi) pathways for future research.Comment: 21 pages, 6 figures, 2 tables, Conference pape

Mott Transition in Degenerate Hubbard Models: Application to Doped Fullerenes

The Mott-Hubbard transition is studied for a Hubbard model with orbital degeneracy N, using a diffusion Monte-Carlo method. Based on general arguments, we conjecture that the Mott-Hubbard transition takes place for U/W \propto \sqrt{N}, where U is the Coulomb interaction and W is the band width. This is supported by exact diagonalization and Monte-Carlo calculations. Realistic parameters for the doped fullerenes lead to the conclusion that stoichiometric A_3 C_60 (A=K, Rb) are near the Mott-Hubbard transition, in a correlated metallic state.Comment: 4 pages, revtex, 1 eps figure included, to be published in Phys.Rev.B Rapid Com

Fluid hydration to prevent post-ERCP pancreatitis in average- to high-risk patients receiving prophylactic rectal NSAIDs (FLUYT trial): Study protocol for a randomized controlled trial

Background: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is the most common complication of ERCP and may run a severe course. Evidence suggests that vigorous periprocedural hydration can prevent PEP, but studies to date have significant methodological drawbacks. Importantly, evidence for its added value in patients already receiving prophylactic rectal non-steroidal anti-inflammatory drugs (NSAIDs) is lacking and the cost-effectiveness of the approach has not been investigated. We hypothesize that combination therapy of rectal NSAIDs and periprocedural hydration would significantly lower the incidence of post-ERCP pancreatitis compared to rectal NSAIDs alone in moderate- to high-risk patients undergoing ERCP. Methods: The FLUYT trial is a multicenter, parallel group, open label, superiority randomized controlled trial. A total of 826 moderate- to high-risk patients undergoing ERCP that receive prophylactic rectal NSAIDs will be randomized to a control group (no fluids or normal saline with a maximum of 1.5 mL/kg/h and 3 L/24 h) or intervention group (lactated Ringer's solution with 20 mL/kg over 60 min at start of ERCP, followed by 3 mL/kg/h for 8 h thereafter). The primary endpoint is the incidence of post-ERCP pancreatitis. Secondary endpoints include PEP severity, hydration-related complications, and cost-effectiveness. Discussion: The FLUYT trial design, including hydration schedule, fluid type, and sample size, maximize its power of identifying a potential difference in post-ERCP pancreatitis incidence in patients receiving prophylactic rectal NSAIDs

Contrast agent dispersion visualized by CE-EUS may be a prediction tool for FOLFIRINOX chemotherapy effectiveness in patients with pancreatic adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) still has a dismal 5-year overall survival of 13 %. Chemotherapy is increasingly used as treatment in both (neo-) adjuvant and palliative conditions. However, the overall survival benefits of chemotherapy must be weighed against significant side effects leading to a reduction in quality of life. CE-EUS and elastography could provide additional information about the vascularization and elasticity of the pancreatic tumor. The aim of this study was to investigate if contrast-enhanced endoscopic ultrasound and/or elastography could be suitable to predict the effectiveness of FOLFIRINOX. Methods: Single center, prospective proof-of-concept study in which intravenous contrast agent was administered and strain ratio was calculated in patients undergoing EUS in their regular diagnostic work-up. Directly after contrast administration, a video of 120 s was recorded and afterwards tracked and fitted by a Modified Local Density Random Walk (mLDRW) model. Results: We included 17 patients. Based on cross-sectional imaging based RECIST criteria, chemotherapy treatment was effective in 11 patients and not effective in 6 patients. The contrast dispersion parameter (κ1) differed significantly between both groups in favor of the responders: 2.994 (IQR 1.670–5.170) vs 1.203 (IQR 0.953–1.756), p = 0.005. The elastography strain ratio was higher in the effectively treated group (20.9 vs 13.6, p = 0.138). Conclusion: This proof-of-concept study showed that the dispersion parameter of the first wave of contrast was 2.5 times higher in patients in whom FOLFIRINOX was effective, suggesting that this parameter could possibly be a reliable prediction tool.</p

Facilitating the Portability of User Applications in Grid Environments

Grid computing promises the ability to connect geographically and organizationally distributed resources to increase effective computational power, resource utilization, and resource accessibility. For grid computing to be successful, users must be able to easily execute the same application on different resources. Different resources, however, may be administered by different organizations with different software installed, di erent le system structures, and different default environment settings. Even within the same organization, the set of software installed on a given resource is in constant flux with additions, upgrades, and removals. Users cannot be expected to understand all of the idiosyncrasies of each resource they may wish to execute jobs on, thus must be provided with automated assistance. This paper describes a new OGSI-compliant grid service (the Naturalization Service) that has been implemented as part of NASA&apos;s Information Power Grid (IPG) project to automatically establish the execution environment for user applications