3,827 research outputs found
Polarized ensembles of random pure states
A new family of polarized ensembles of random pure states is presented. These
ensembles are obtained by linear superposition of two random pure states with
suitable distributions, and are quite manageable. We will use the obtained
results for two purposes: on the one hand we will be able to derive an
efficient strategy for sampling states from isopurity manifolds. On the other,
we will characterize the deviation of a pure quantum state from separability
under the influence of noise.Comment: 14 pages, 1 figur
Towards a Smarter organization for a Self-servicing Society
Traditional social organizations such as those for the management of
healthcare are the result of designs that matched well with an operational
context considerably different from the one we are experiencing today. The new
context reveals all the fragility of our societies. In this paper, a platform
is introduced by combining social-oriented communities and complex-event
processing concepts: SELFSERV. Its aim is to complement the "old recipes" with
smarter forms of social organization based on the self-service paradigm and by
exploring culture-specific aspects and technological challenges.Comment: Final version of a paper published in the Proceedings of
International Conference on Software Development and Technologies for
Enhancing Accessibility and Fighting Info-exclusion (DSAI'16), special track
on Emergent Technologies for Ambient Assisted Living (ETAAL
Mass gaps of a gauge theory with three fermion flavors in 1 + 1 dimensions
We consider a gauge theory coupled to three degenerate massive
flavors of fermions, which we term "QZD". The spectrum can be computed in
dimensions using tensor networks. In weak coupling the spectrum is that of the
expected mesons and baryons, although the corrections in weak coupling are
nontrivial, analogous to those of non-relativistic QED in 1+1 dimensions. In
strong coupling, besides the usual baryon, the singlet meson is a baryon
anti-baryon state. For two special values of the coupling constant, the
lightest baryon is degenerate with the lightest octet meson, and the lightest
singlet meson, respectively.Comment: 17 pages and 10 figure
Liposomal delivery of hydrophobic RAMBAs provides good bioavailability and significant enhancement of retinoic acid signalling in neuroblastoma tumour cells
Retinoid treatment is employed during residual disease treatment in neuroblastoma, where the aim is to induce neural differentiation or death in tumour cells. However, although therapeutically effective, retinoids have only modest benefits and suffer from poor pharmacokinetic properties. In vivo, retinoids induce CYP26 enzyme production in the liver, enhancing their own rapid metabolic clearance, while retinoid resistance in tumour cells themselves is considered to be due in part to increased CYP26 production. Retinoic acid metabolism blocking agents (RAMBAs), which inhibit CYP26 enzymes, can improve retinoic acid pharmacokinetics in pre-clinical neuroblastoma models. Here we demonstrate that in cultured neuroblastoma tumour cells, RAMBAs enhance retinoic acid action as seen by morphological differentiation, AKT signalling and suppression of MYCN protein. Although active as retinoid enhancers, these RAMBAs are highly hydrophobic and their effective delivery in humans will be very challenging. Here we demonstrate that such RAMBAs can be loaded efficiently into cationic liposomal particles, where the RAMBAs achieve good bioavailability and activity in cultured tumour cells. This demonstrates the efficacy of RAMBAs in enhancing retinoid signaling in neuroblastoma cells and shows for the first time that liposomal delivery of hydrophobic RAMBAs is a viable approach, providing novel opportunities for their delivery and application in humans
Robust gates for holonomic quantum computation
Non Abelian geometric phases are attracting increasing interest because of
possible experimental application in quantum computation. We study the effects
of the environment (modelled as an ensemble of harmonic oscillators) on a
holonomic transformation and write the corresponding master equation. The
solution is analytically and numerically investigated and the behavior of the
fidelity analyzed: fidelity revivals are observed and an optimal finite
operation time is determined at which the gate is most robust against noise.Comment: 11 pages, 6 figure
Robustness against parametric noise of non ideal holonomic gates
Holonomic gates for quantum computation are commonly considered to be robust
against certain kinds of parametric noise, the very motivation of this
robustness being the geometric character of the transformation achieved in the
adiabatic limit. On the other hand, the effects of decoherence are expected to
become more and more relevant when the adiabatic limit is approached. Starting
from the system described by Florio et al. [Phys. Rev. A 73, 022327 (2006)],
here we discuss the behavior of non ideal holonomic gates at finite operational
time, i.e., far before the adiabatic limit is reached. We have considered
several models of parametric noise and studied the robustness of finite time
gates. The obtained results suggest that the finite time gates present some
effects of cancellation of the perturbations introduced by the noise which
mimic the geometrical cancellation effect of standard holonomic gates.
Nevertheless, a careful analysis of the results leads to the conclusion that
these effects are related to a dynamical instead of geometrical feature.Comment: 8 pages, 8 figures, several changes made, accepted for publication on
Phys. Rev.
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