215 research outputs found

    Model aware execution of composite web services

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    In the Service Oriented Architecture (SOA) services are computational elements that are published, discovered, consumed and aggregated across platform and organizational borders. The most commonly used technology to achieve SOA are Web Services (WSs). This is due to standardization process (WSDL, SOAP, UDDI standards) and a wide range of available infrastructure and tools. A very interesting aspect of WSs is their composeability. WSs can be easily aggregated into complex workflows, called Composite Web Services (CWSs). These compositions of services enable further reuse and in this way new, even more complex, systems are built.Although there are many languages to specify or implement workflows, in the service-oriented systems BPEL (Business Process Execution Language) is widely accepted. With this language WSs are orchestrated and then executed with specialized engines (like ActiveBPEL). While being very popular, BPEL has certain limitations in monitoring and optimizing executions of CWSs. It is very hard with this language to adapt CWSs to changes in the performance of used WSs, and also to select the optimal way to execute a CWS. To overcome the limitations of BPEL, I present a model-aware approach to execute CWSs. To achieve the model awareness the Coloured Petri Nets (CPN) formalism is considered as the basis of the execution of CWSs. This is different than other works in using formal methods in CWSs, which are restricted to purposes like verification or checking of correctness. Here the formal and unambiguous notation of the CPN is used to model, analyze, execute and monitor CWSs. Furthermore this approach to execute CWSs, which is based on the CPN formalism, is implemented in the model-aware middleware. It is also demonstrated how the middleware improves the performance and reliability of CWSs

    Etf Primary Market Structure And Its Efficiency

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    The primary market of many US registered ETFs exhibits an oligopolistic structure, which is shown to have relevant implications for the pricing efficiency of those financial products. I show that the entry of an additional Authorized Participant (AP) corresponds to a decrease in the magnitude of ETF price deviations from Net Asset Value (NAV) of at least one basis point in ETFs with high primary market concentration. I build a dynamic equilibrium model of ETF primary market arbitrage that describes the trade-off faced by monopolistically competitive APs between waiting for mispricing to widen and pre-empting competitors from eliminating it. In the model, the creation unit size is shown to be an important friction driving the entry decision and, therefore, the magnitude of mispricing. Indeed, in the data, around one-third of all primary market transactions amount to one creation unit, suggesting that it is often a binding constraint. ETF split events and the creation unit size changes help to identify shocks to the dollar value of creation unit size empirically. I show that by cutting the creation unit size in half, mispricing decreases by almost two basis points, a magnitude consistent with that implied by my quantitative model

    (Benzoato-κ2 O,O′)(quinoline-2-carboxyl­ato-κ2 N,O)(quinoline-2-carboxylic acid-κ2 N,O)manganese(II)

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    The crystal structure of the title compound, [Mn(C7H5O2)(C10H6NO2)(C10H7NO2)], contains manganese(II) ions six-coordinated in a distorted octa­hedral environment. The equatorial plane is occupied by four O atoms, two from the carboxyl­ate group of the benzoate ion, the other two from carboxyl­ate/carboxyl groups of the quinaldate/quinaldic acid mol­ecules. The axial positions are occupied by the N atoms of the quinoline ring systems. The metal ion lies on a twofold rotation axis that bisects the benzoate ligand; the quinaldate and quinaldic acid ligands are therefore equivalent by symmetry, and the carboxylate/carboxyl groups are disordered. The complexes are joined together by hydrogen bonds between the carboxyl­ate/carboxyl groups of adjacent quinaldate/quinaldic acid mol­ecules, forming zigzag chains that run along the c axis

    Bis[(2-quinol­yl)methane­diol-κ2 N,O](sulfato-κO)copper(II) dihydrate

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    In the title compound, [Cu(SO4)(C10H9NO2)2]·2H2O, the CuII ion is chelated by two (2-quinol­yl)methane­diol ligands and coordinated by a monodentate sulfate ligand in a distorted trigonal–bipyramidal environment, with O atoms occupying the equatorial sites and N atoms in the axial sites. The dihedral angle between the two essentially planar quinoline ring systems is 45.02 (9)°. In the crystal structure, an extensive O—H⋯O hydrogen-bonding network forms layers parallel to the ab plane

    (Benzoato-κ2 O,O′)(quinoline-2-carboxyl­ato-κ2 N,O)(quinoline-2-carboxylic acid-κ2 N,O)copper(II)

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    The crystal structure of the title compound, [Cu(C10H6NO2)(C7H5O2)(C10H7NO2)], contains copper(II) ions five-coordinated in a distorted trigonal-bipyramidal environment. The equatorial plane is occupied by three O atoms, one from the carboxyl­ate group of the benzoate ion considered as occupying a single coordination site, the other two from two carboxyl­ate groups of the quinaldic acid and quinaldate ligands. The axial positions are occupied by the N atoms of the quinoline ring system. The metal ion lies on a twofold axis that bisects the benzoate ion. The quinaldate and quinaldic acid ligands are equivalent by symmetry, and the carboxyl­ate/carboxyl groups are disordered. The disordered H atom is shared between the carboxyl­ate groups of adjacent quinaldic acid mol­ecules. Such hydrogen bonds delineate zigzag chains that run along the c axis. The structure is very similar to that of the MnII analog

    Opicapone in UK clinical practice: effectiveness, safety and cost analysis in patients with Parkinson's disease.

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    Aim: This subanalysis of the OPTIPARK study aimed to confirm the effectiveness and safety of opicapone in patients with Parkinson's disease and motor fluctuations in clinical practice specifically in the UK and to assess the impact of opicapone on treatment costs. Methods: Patients received opicapone added to levodopa for 6 months. Clinical outcomes were assessed at 3 and 6 months and treatment costs at 6 months. Results: Most patients' general condition improved at 3 months, with sustained improvements reported at 6 months. Opicapone improved motor and non-motor symptoms at both timepoints, was generally well tolerated and reduced total treatment costs by GBP 3719. Conclusion: Opicapone added to levodopa resulted in clinical improvements and reduced treatment costs across UK clinical practice
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