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Discovering secure service compositions
Security is an important concern for service based systems, i.e., systems that are composed of autonomous and distributed software services. This is because the overall security of such systems depends on the security of the individual services they deploy and, hence, it is difficult to assess especially in cases where the latter services must be discovered and composed dynamically. This paper presents a novel approach for discovering secure compositions of software services. This approach is based on secure service orchestration patterns, which have been proven to provide certain security properties and can, therefore, be used to generate service compositions that are guaranteed to satisfy these properties by construction. The paper lays the foundations of the secure service orchestration patterns, and presents an algorithm that uses the patterns to generate secure service compositions and a tool realising our entire approach
The Ljapunov-Schmidt reduction for some critical problems
This is a survey about the application of the Ljapunov-Schmidt reduction for
some critical problems
Features of collisionless turbulence in the intracluster medium from simulated Faraday Rotation maps
Observations of the intracluster medium (ICM) in galaxy clusters suggest for
the presence of turbulence and the magnetic fields existence has been proved
through observations of Faraday Rotation and synchrotron emission. The ICM is
also known to be filled by a rarefied weakly collisional plasma. In this work
we study the possible signatures left on Faraday Rotation maps by collisionless
instabilities. For this purpose we use a numerical approach to investigate the
dynamics of the turbulence in collisionless plasmas based on an
magnetohydrodynamical (MHD) formalism taking into account different levels of
pressure anisotropy. We consider models covering the sub/super-Alfv\'enic and
trans/supersonic regimes, one of them representing the fiducial conditions
corresponding to the ICM. From the simulated models we compute Faraday Rotation
maps and analyze several statistical indicators in order to characterize the
magnetic field structure and compare the results obtained with the
collisionless model to those obtained using standard collisional MHD framework.
We find that important imprints of the pressure anisotropy prevails in the
magnetic field and also manifest in the associated Faraday Rotation maps which
evidence smaller correlation lengths in the collisionless MHD case. These
points are remarkably noticeable for the case mimicking the conditions
prevailing in ICM. Nevertheless, in this study we have neglected the decrease
of pressure anisotropy due to the feedback of the instabilities that naturally
arise in collisionless plasmas at small scales. This decrease may not affect
the statistical imprint differences described above, but should be examined
elsewhere.Comment: 24 pages, 15 figures, MNRAS accepte
Calculation of the energy spectrum of a two-electron spherical quantum dot
We study the energy spectrum of the two-electron spherical parabolic quantum
dot using the exact Schroedinger, the Hartree-Fock, and the Kohn-Sham
equations. The results obtained by applying the shifted-1/N method are compared
with those obtained by using an accurate numerical technique, showing that the
relative error is reasonably small, although the first method consistently
underestimates the correct values. The approximate ground-state Hartree-Fock
and local-density Kohn-Sham energies, estimated using the shifted-1/N method,
are compared with accurate numerical self-consistent solutions. We make some
perturbative analyses of the exact energy in terms of the confinement strength,
and we propose some interpolation formulae. Similar analysis is made for both
mean-field approximations and interpolation formulae are also proposed for
these exchange-only ground-state cases.Comment: 18 pages, LaTeX, 2 figures-ep
COX-2 targeting in cancer: a new beginning?
Cyclo-oxygenase-2 (COX-2), the inducible enzyme catalyzing the rate-limiting step in the conversion of arachidonic acid into eicosanoids, is overexpressed in a wide variety of malignancies and associates with poor prognostic features [1]. Consequently, selective COX-2 inhibitors have been explored as therapeutic or chemopreventive agents in different settings; however, initial enthusiasm was tempered by reports of substantial gastrointestinal toxicity as well as of increased cardiovascular risk, mostly coming from postmarketing use as anti-inflammatory drugs and Cancer Research Campaign (UK) chemoprevention trials and eventually resulting in the withdrawal of rofecoxib from the market [2]
MHD Models of Axisymmetric Protostellar Jets
We present the results of a series of axisymmetric time-dependent
magnetohydrodynamic (MHD) simulations of the propagation of cooling, overdense
jets, motivated by the properties of outflows associated with young stellar
objects. A variety of initial field strengths and configurations are explored
for both steady and time-variable (pulsed) jets. Even apparently weak magnetic
fields with strengths B < 60 micro-G in the pre-shocked jet beam can have a
significant effect on the dynamics, for example by altering the density, width,
and fragmentation of thin shells formed by cooling gas. A linear analysis
predicts that axisymmetric pinch modes of the MHD Kelvin-Helmholtz instability
should grow only slowly for the highly supermagnetosonic jets studied here; we
find no evidence for them in our simulations. Some of our models appear
unstable to current-driven pinch modes, however the resulting pressure and
density variations induced in the jet beam are not large, making this mechanism
an unlikely source of emission knots in the jet beam. In the case of pulsed
jets, radial hoop stresses confine shocked jet material in the pulses to the
axis, resulting in a higher density in the pulses in comparison to purely
hydrodynamic models.Comment: 28 pages, 16 figures, accepted by Ap.
The role of pressure anisotropy in the turbulent intracluster medium
In low-density plasma environments, such as the intracluster medium (ICM),
the Larmour frequency is much larger than the ion-ion collision frequency. In
such a case, the thermal pressure becomes anisotropic with respect to the
magnetic field orientation and the evolution of the turbulent gas is more
correctly described by a kinetic approach. A possible description of these
collisionless scenarios is given by the so-called kinetic magnetohydrodynamic
(KMHD) formalism, in which particles freely stream along the field lines, while
moving with the field lines in the perpendicular direction. In this way a
fluid-like behavior in the perpendicular plane is restored. In this work, we
study fast growing magnetic fluctuations in the smallest scales which operate
in the collisionless plasma that fills the ICM. In particular, we focus on the
impact of a particular evolution of the pressure anisotropy and its
implications for the turbulent dynamics of observables under the conditions
prevailing in the ICM. We present results from numerical simulations and
compare the results which those obtained using an MHD formalism.Comment: 7 pages, 14 figures, Journal of Physics: Conference Serie
A clinical pilot study on the effect of the probiotic Lacticaseibacillus rhamnosus TOM 22.8 strain in women with vaginal dysbiosis
Lactobacilli with probiotic features play an essential role in maintaining a balanced vaginal microbiota and their administration has been suggested for the treatment and prevention of vaginal dysbiosis. The present study was aimed to in vitro and in vivo investigate the probiotic potential of the Lacticaseibacillus rhamnosus TOM 22.8 strain, isolated from the vaginal ecosystem of a healthy woman. For this purpose, safety and functional properties were in depth evaluated. The strain exhibited a broad spectrum of antagonistic activity against vaginal pathogens; adhesion capacity to both the vaginal VK2/E6E7 and the intestinal Caco-2 cells; anti-inflammatory and antioxidant activities, suggesting its promising probiotic features. In addition, an in vivo pilot-study was planned. Based on both clinical and microbiological parameters, the oral or vaginal strain administration, determined a significant pathogens reduction after 10 days of administration and a maintenance of eubiosis up to 30 days after the end of the treatment. Therefore, the L. rhamnosus TOM 22.8 strain can be proposed as valuable oral and/or vaginal treatment for vaginal dysbiosis
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