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Editorial: Innovative Technologies and Clinical Applications for Invasive and Non-invasive Neuromodulation: From the Workbench to the Bedside.
Process membership in asynchronous environments
The development of reliable distributed software is simplified by the ability to assume a fail-stop failure model. The emulation of such a model in an asynchronous distributed environment is discussed. The solution proposed, called Strong-GMP, can be supported through a highly efficient protocol, and was implemented as part of a distributed systems software project at Cornell University. The precise definition of the problem, the protocol, correctness proofs, and an analysis of costs are addressed
Foreground removal requirements for measuring large-scale CMB B-modes in light of BICEP2
The most convincing confirmation that the B-mode polarization signal detected
at degree scales by BICEP2 is due to the Cosmic Microwave Background (CMB)
would be the measurement of its large-scale counterpart. We assess the
requirements for diffuse component separation accuracy over large portions of
the sky in order to measure the large-scale B-mode signal corresponding to a
tensor to scalar ratio of r=0.1-0.2.
We use the method proposed by Bonaldi & Ricciardi (2011) to forecast the
performances of different simulated experiments taking into account noise and
foreground removal issues. We do not consider instrumental systematics, and we
implicitly assume that they are not the dominant source of error. If this is
the case, the confirmation of an r=0.1-0.2 signal is achievable by Planck even
for conservative assumptions regarding the accuracy of foreground cleaning. Our
forecasts suggest that the combination of this experiment with BICEP2 will lead
to an improvement of 25-45% in the constraint on r.
A next-generation CMB polarization satellite, represented in this work by the
COrE experiment, can reduce dramatically (by almost another order of magnitude)
the uncertainty on r. In this case, however, the accuracy of foreground removal
becomes critical to fully benefit from the increase in sensitivity.Comment: 8 pages, 3 figures, 1 table. Accepted by MNRA
Legal medical consideration of alzheimer’s disease patients’ dysgraphia and cognitive dysfunction: a 6 month follow up
Background: The purpose of this study was to investigate the ability of Alzheimer’s disease
(AD) patients to express intentions and desires, and their decision-making capacity. This study
examines the findings from a 6-month follow-up of our previous results in which 30 patients
participated.
Materials and methods: The patient’s cognition was examined by conducting the tests of 14
questions and letter-writing ability over a period of 19 days, and it was repeated after 6 months.
The difference between these two cognitive measures (PQ1 before–PQ2 before), tested previously
and later the writing test, was designated DΔ before. The test was repeated after 6 months,
and PQ1 after–PQ2 after was designated DΔ after.
Results: Several markedly strong relationships between dysgraphia and other measures of
cognitive performance in AD patients were observed. The most aged patients (over 86 years),
despite less frequency, maintain the cognitive capacity manifested in the graphic expressions.
A document, written by an AD patient presents an honest expression of the patient’s intention
if that document is legible, clear, and comprehensive.
Conclusion: The identification of impairment/deficits in writing and cognition during different
phases of AD may facilitate the understanding of disease progression and identify the occasions
during which the patient may be considered sufficiently lucid to make decisions.
Keywords: cognition, intentions, unfit to plead, consen
Oscillatory phase transition and pulse propagation in noisy integrate-and-fire neurons
We study non-locally coupled noisy integrate-and-fire neurons with the
Fokker-Planck equation. A propagating pulse state and a wavy state appear as a
phase transition from an asynchronous state. We also find a solution in which
traveling pulses are emitted periodically from a pacemaker region.Comment: 9 pages, 4 figure
A chemically driven fluctuating ratchet model for actomyosin interaction
With reference to the experimental observations by T. Yanagida and his
co-workers on actomyosin interaction, a Brownian motor of fluctuating ratchet
kind is designed with the aim to describe the interaction between a Myosin II
head and a neighboring actin filament. Our motor combines the dynamics of the
myosin head with a chemical external system related to the ATP cycle, whose
role is to provide the energy supply necessary to bias the motion. Analytical
expressions for the duration of the ATP cycle, for the Gibbs free energy and
for the net displacement of the myosin head are obtained. Finally, by
exploiting a method due to Sekimoto (1997, J. Phys. Soc. Jpn., 66, 1234), a
formula is worked out for the amount of energy consumed during the ATP cycle.Comment: 15 pages. 1 figur
Reaction mechanisms involved in the production of neutron-rich isotopes
The reaction mechanisms best suited for the production of neutron-rich
nuclei, fragmentation and fission, are discussed. Measurements of the
production cross sections of reaction residues together with model calculations
allow to conclude about the expected production rates of neutron-rich isotopes
in future facilities.Comment: 9 pages, 8 figures Proceedings of the Third International Conference
on Fission and Properties of Neutron-Rich Nuclei November 3-9, 2002, Sanibel
Island, Florida, US
A stochastic model for the stepwise motion in actomyosin dynamics
A jump-diffusion process is proposed to describe the displacements performed
by single myosin heads along actin filaments during the rising phases. The
process consists of the superposition of a Wiener and a jump process, with
jumps originated by sequences of Poisson-distributed energy-supplying pulses.
In a previous paper, the amplitude of the jumps was described by a mixture of
two Gaussian distributions. To embody the effects of ATP hydrolysis, we now
refine such a model by assuming that the jumps' amplitude is described by a
mixture of three Gaussian distributions. This model has been inspired by the
experimental data of T. Yanagida and his co-workers concerning observations at
single molecule processes level.Comment: 9 pages, 4 figure
Neutrino masses and mixings in SO(10)
Assuming a Zee-like matrix for the right-handed neutrino Majorana masses in
the see-saw mechanism, one gets maximal mixing for vacuum solar oscillations, a
very small value for and an approximate degeneracy for the two lower
neutrino masses. The scale of right-handed neutrino Majorana masses is in good
agreement with the value expected in a SO(10) model with Pati-Salam SU(4)\ts
SU(2)\ts SU(2) intermediate symmetry.Comment: 11 pages, no figures. References adde
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