14,735 research outputs found
Theory of continuum percolation II. Mean field theory
I use a previously introduced mapping between the continuum percolation model
and the Potts fluid to derive a mean field theory of continuum percolation
systems. This is done by introducing a new variational principle, the basis of
which has to be taken, for now, as heuristic. The critical exponents obtained
are , and , which are identical with the mean
field exponents of lattice percolation. The critical density in this
approximation is \rho_c = 1/\ve where \ve = \int d \x \, p(\x) \{ \exp [-
v(\x)/kT] - 1 \}. p(\x) is the binding probability of two particles
separated by \x and v(\x) is their interaction potential.Comment: 25 pages, Late
Kaon physics with the KLOE detector
In this paper we discuss the recent finalized analyses by the KLOE experiment
at DANE: the CPT and Lorentz invariance test with entangled pairs, and the precision measurement of the branching fraction of
the decay . We also present the
status of an ongoing analysis aiming to precisely measure the mass
Traces for star products on the dual of a Lie algebra
In this paper, we describe all traces for the BCH star-product on the dual of
a Lie algebra. First we show by an elementary argument that the BCH as well as
the Kontsevich star-product are strongly closed if and only if the Lie algebra
is unimodular. In a next step we show that the traces of the BCH star-product
are given by the \ad-invariant functionals. Particular examples are the
integration over coadjoint orbits. We show that for a compact Lie group and a
regular orbit one can even achieve that this integration becomes a positive
trace functional. In this case we explicitly describe the corresponding GNS
representation. Finally we discuss how invariant deformations on a group can be
used to induce deformations of spaces where the group acts on.Comment: 18 pages, LaTeX2e. Updated reference
Modeling and steering magneto-elastic micro-swimmers inspired by the motility of sperm cells
Controlling artificial devices that mimic the motion of real microorganisms, is attracting increasing interest, both from the mathematical point of view and applications. A model for a magnetically driven slender micro-swimmer, mimicking a sperm cell is presented, supported by two examples showing how to steer it. Using the Resistive Force Theory (RTF) approach [J. Gray and J. Hancock, J. Exp. Biol. 32, 802 (1955)] to describe the hydrodynamic forces, the micro-swimmer can be described by a driftless affine control system where the control is an external magnetic field. Moreover we discuss through at first an asymptotic analysis and then by numerical simulations how to realize different kinds of paths
An X-ray and Optical Study of Matter Distribution in the Galaxy Cluster A 2319
A new analysis of velocity distribution, optical photometry and X-ray surface
brightness from ROSAT PSPC data of the galaxy cluster A 2319 is presented. The
temperature profile derived from ASCA data (Markevitch et al.,1996) is taken
into account. A method to check the hydrostatic model in the presence of a
temperature gradient is proposed. Consistency of the hydrostatic isothermal
model and the explanation of the "beta-discrepancy" are discussed. Galaxy and
gas density profiles of the main component A 2319A are derived, allowing for
the effect of the secondary component A 2319B. The inadequacy of a polytropic
model, which would produce a binding mass decrease with respect to the
isothermal beta-model, is discussed. A simple interpolation of the temperature
profile provides instead an increase of the binding mass and a lower baryon
fraction thus mitigating the "baryon catastrophe". Assuming as typical the
value f_b ~ 0.2, a comparison with the most recent estimate of Omega_b(nucl)
implies for the cosmological parameter Omega_o less than 0.4.Comment: 7 pages, 2 tables, 8 figure
Right to Serve, Right to Lead: Lives and Legacies of the USCT
This is a catalog for an exhibit that follows the evolution of African-American participation in the Civil War, from slaves, to contrabands, to soldiers of the United States Colored Troops (USCT), as well as the lives of black veterans beyond the war, and their ultimate military and social legacy. Using a variety of period items, it creates a narrative that stretches from the Antebellum Period to the current day. In doing so, the exhibit shows how black sacrifice on the battlefield redefined the war\u27s purpose throughout the divided nation, how Jim Crowe suppressed the memory of black participation after Reconstruction, and how the illustrious African-American military tradition left by the USCT endures to this day in their modern heirs
Expert-Augmented Machine Learning
Machine Learning is proving invaluable across disciplines. However, its
success is often limited by the quality and quantity of available data, while
its adoption by the level of trust that models afford users. Human vs. machine
performance is commonly compared empirically to decide whether a certain task
should be performed by a computer or an expert. In reality, the optimal
learning strategy may involve combining the complementary strengths of man and
machine. Here we present Expert-Augmented Machine Learning (EAML), an automated
method that guides the extraction of expert knowledge and its integration into
machine-learned models. We use a large dataset of intensive care patient data
to predict mortality and show that we can extract expert knowledge using an
online platform, help reveal hidden confounders, improve generalizability on a
different population and learn using less data. EAML presents a novel framework
for high performance and dependable machine learning in critical applications
Use of biological drugs in patients with psoriasis and psoriatic arthritis in italy: Results from the PSONG survey
This Italian multicenter retrospective study compared the drug survival and efficacy of differentanti-TNF agents in psoriasis (PsO) and psoriatic arthritis (PsA) patients. A database of PsO/PsApatients treated with adalimumab, etanercept, and infliximab from May 2013 to May 2014 wasanalyzed. PASI 75, 90, and 100 was calculated at each time point to evaluate efficacy. Drug sur-vival rate and probability of maintaining PASI response were evaluated. The impact of dependentvariables on probability of PASI 75 loss was evaluated by logistic regression. 1,235 patients wereincluded, 577 with PsO and 658 with PsA. Highest survival rates were observed with adalimumabfollowed by etanercept and infliximab in PsO and PsA patients. The probability of maintainingPASI response was significantly higher for adalimumab followed by infliximab. For PsO patients,the odds of losing PASI 75 was higher in etanercept-treated patients (OR: 8.1; 95% CI: 4.2–15.6,p<.001) or infliximab (OR: 6.6; 95% CI: 2.6–16.3,p<.001) vs. adalimumab. Likewise, for PsApatients the odds of losing PASI 75 was higher in etanercept-treated patients (OR: 2.3; 95% CI:1.4–3.8,p5.01) or infliximab (OR: 2.2; 95% CI: 1.1–4.1,p5.018) vs. adalimumab. Adalimumabcould be the best therapeutic option over other anti-TNF agents for the treatment of PsO and PsApatients
Leptogenesis from Soft Supersymmetry Breaking (Soft Leptogenesis)
Soft leptogenesis is a scenario in which the cosmic baryon asymmetry is
produced from a lepton asymmetry generated in the decays of heavy sneutrinos
(the partners of the singlet neutrinos of the seesaw) and where the relevant
sources of CP violation are the complex phases of soft supersymmetry-breaking
terms. We explain the motivations for soft leptogenesis, and review its basic
ingredients: the different CP-violating contributions, the crucial role played
by thermal corrections, and the enhancement of the efficiency from lepton
flavour effects. We also discuss the high temperature regime GeV in
which the cosmic baryon asymmetry originates from an initial asymmetry of an
anomalous -charge, and soft leptogenesis reembodies in -genesis.Comment: References updated. Some minor corrections to match the published
versio
On fast CP violating interactions in leptogenesis
We show that when the relevant CP violating interactions in leptogenesis are
fast, the different matter density asymmetries are determined at each instant
by a balance condition between the amount of asymmetry being created and
destroyed. This fact allows to understand in a simple way many features of
leptogenesis in the strong washout regime. In particular, we find some
non-trivial effects of flavour changing interactions that conserve lepton
number, which are specially relevant in models for leptogenesis that rely
heavily on flavour effects.Comment: V2: To match published version in JCAP. Minor changes, including one
figure, with respect to V1. 17 pages, 4 figure
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