Mass and orbit constraints of the gamma-ray binary LS 5039

We present the results of space-based photometric and ground-based spectroscopic observing campaigns on the gamma-ray binary LS 5039. The new orbital and physical parameters of the system are similar to former results, except we found a lower eccentricity. Our MOST-data show that any broad-band optical photometric variability at the orbital period is below the 2 mmag level. Light curve simulations support the lower value of eccentricity and imply that the mass of the compact object is higher than 1.8 solar masses.Comment: 2 pages, 1 figure (with 2 panels); to be published in the Proceedings: From Interacting Binaries to Exoplanets: Essential Modeling Tools, IAU Symposium 282 (18-22 July, 2011, Tatranska Lomnica, Slovakia

Enabling modular design of an application-level auto-scaling and orchestration framework using tosca-based application description templates

This paper presents a novel approach to writing TOSCA templates for application reusability and portability in a modular auto-scaling and orchestration framework (MiCADO). The approach defines cloud resources as well as application containers in a flexible and generic way, and allows for those definitions to be extended with specific properties related to a desired container orchestrator chosen at deployment time. The approach is demonstrated in a proof-of-concept where only a minor change was required to a previously used application template in order to achieve the successful deployment and lifecycle management of the popular web authoring tool Wordpress on a new realization of the MiCADO framework featuring a different container orchestrator

Nova Cygni 2001/2 = V2275 Cyg

We present an analysis of low- and medium resolution spectra of the very fast nova, Nova Cygni 2001/2 (V2275 Cyg) obtained at nine epochs in August, September and October, 2001. The expansion velocity from hydrogen Balmer lines is found to be 2100 km/s, although early H-alpha profile showed a weak feature at -3500 km/s, too. The overall appearance of the optical spectrum is dominated by broad lines of H, He and N, therefore, the star belongs to the ``He/N'' subclass of novae defined by Williams (1992). Interstellar lines and bands, as well as BV photometry taken from the literature yielded to a fairly high reddening of E(B-V)=1.0+/-0.1 mag. The visual light curve was used to deduce M_V by the maximum magnitude versus rate of decline relationship. The resulting parameters are: t_0=2452141.4(+0.1)(-0.5), t_2=2.9+/-0.5 days, t_3=7+/-1 days, M_V=-9.7+/-0.7 mag. Adopting these parameters, the star lies between 3 kpc and 8 kpc from the Sun.Comment: 5 pages, 5 figures, accepted for publication in A&

Describing and Processing Topology and Quality of Service Parameters of Applications in the Cloud

Typical cloud applications require high-level policy driven orchestration to achieve efficient resource utilisation and robust security to support different types of users and user scenarios. However, the efficient and secure utilisation of cloud resources to run applications is not trivial. Although there have been several efforts to support the coordinated deployment, and to a smaller extent the run-time orchestration of applications in the Cloud, no comprehensive solution has emerged until now that successfully leverages applications in an efficient, secure and seamless way. One of the major challenges is how to specify and manage Quality of Service (QoS) properties governing cloud applications. The solution to address these challenges could be a generic and pluggable framework that supports the optimal and secure deployment and run-time orchestration of applications in the Cloud. A specific aspect of such a cloud orchestration framework is the need to describe complex applications incorporating several services. These application descriptions must specify both the structure of the application and its QoS parameters, such as desired performance, economic viability and security. This paper proposes a cloud technology agnostic approach to application descriptions based on existing standards and describes how these application descriptions can be processed to manage applications in the Cloud

chronic administration of quercetin induces biomechanical and pharmacological remodeling in the rat coronary arteries

Acute dilation brought about by the dietary flavonoid quercetin in coronary arterioles has been described earlier, but no information is available on its chronic effects. Male Wistar rats (body weight about 190 g) were divided to two groups: the quercetin-treated group (n=22) had quercetin supplementation of approximately 30 mg/kg/day, whereas the control group (n=20) had none. After eight weeks of treatment, intramural coronary arterioles with identical passive diameters (178±14 µm and 171±9 µm) were prepared and their biomechanics and pharmacological reactivities were tested using pressure arteriography ex vivo. The spontaneous tone of quercetin-treated arteries was higher (16.5±1.9 % vs. 12.9±0.9 %), which resulted in a reduced lumen size (144±9 μm vs. 167±12 μm), thicker vascular wall (22.6±1.8 μm vs. 17.4±1.6 μm) and decreased tangential wall stress (16.8±1.1 kPa vs. 20.5±1.6 kPa) in supplemented animals (in spontaneous tone at 50 mm Hg, p<0.01 in all these comparisons). Elevated basal NO release resulted in increased endothelial dilation in quercetin-treated animals, especially at higher intraluminal pressures (10.8±2.5 % vs. 5.7±1.3 % at 70 mm Hg, p<0.01). We found remodeling of the geometry of coronary arterioles to ensure higher dilatory reserve and nitrogen monoxide production, as well as lowered elastic stress of the vessel wall

TWO-PROTON RADIOACTIVITY: THE INTERESTING CASE OF 67Kr AND FURTHER STUDIES

We report on the observation of 67Kr that has been produced in an experiment performed at the RIKEN/BigRIPS facility. The two-proton decay of 67Kr has been evidenced and this nucleus is thus the fourth observed long lived ground-state two-proton emitter, after 45Fe, 48Ni and 54Zn. In addition, the decay of several isotopes in the mass region has been investigated. While for previous cases of two-proton radioactivity, the theoretical models could reproduce the measured data, this is not the case anymore for 67Kr. Two interpretations have been proposed to explain this discrepancy: a transition between real two-proton and sequential decay or the influence of deformation. These hypotheses will be tested in future experiments by measuring the angular and energy correlations of the emitted proton

Teleportation: from probability distributions to quantum states

The role of the off-diagonal density matrix elements of the entangled pair is investigated in quantum teleportation of a qbit. The dependence between them and the off-diagonal elements of the teleported density matrix is shown to be linear. In this way the ideal quantum teleportation is related to an entirely classical communication protocol: the one-time pad cypher. The latter can be regarded as the classical counterpart of Bennett's quantum teleportation scheme. The quantum-to-classical transition is demonstrated on the statistics of a gedankenexperiment.Comment: 11 pages, 1 figure, accepted for publication in J. Phys. A (Math. Gen.