Life Chaos is Associated with Reduced HIV Testing, Engagement in Care, and ART Adherence Among Cisgender Men and Transgender Women upon Entry into Jail.

Life chaos, the perceived inability to plan for and anticipate the future, may be a barrier to the HIV care continuum for people living with HIV who experience incarceration. Between December 2012 and June 2015, we interviewed 356 adult cisgender men and transgender women living with HIV in Los Angeles County Jail. We assessed life chaos using the Confusion, Hubbub, and Order Scale (CHAOS) and conducted regression analyses to estimate the association between life chaos and care continuum. Forty-eight percent were diagnosed with HIV while incarcerated, 14% were engaged in care 12 months prior to incarceration, mean antiretroviral adherence was 65%, and 68% were virologically suppressed. Adjusting for sociodemographics, HIV-related stigma, and social support, higher life chaos was associated with greater likelihood of diagnosis while incarcerated, lower likelihood of engagement in care, and lower adherence. There was no statistically significant association between life chaos and virologic suppression. Identifying life chaos in criminal-justice involved populations and intervening on it may improve continuum outcomes

Wigner chaos and the fourth moment

We prove that a normalized sequence of multiple Wigner integrals (in a fixed order of free Wigner chaos) converges in law to the standard semicircular distribution if and only if the corresponding sequence of fourth moments converges to 2, the fourth moment of the semicircular law. This extends to the free probabilistic, setting some recent results by Nualart and Peccati on characterizations of central limit theorems in a fixed order of Gaussian Wiener chaos. Our proof is combinatorial, analyzing the relevant noncrossing partitions that control the moments of the integrals. We can also use these techniques to distinguish the first order of chaos from all others in terms of distributions; we then use tools from the free Malliavin calculus to give quantitative bounds on a distance between different orders of chaos. When applied to highly symmetric kernels, our results yield a new transfer principle, connecting central limit theorems in free Wigner chaos to those in Gaussian Wiener chaos. We use this to prove a new free version of an important classical theorem, the Breuer-Major theorem.Comment: Published in at http://dx.doi.org/10.1214/11-AOP657 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org

Defect turbulence in inclined layer convection

We report experimental results on the defect turbulent state of undulation chaos in inclined layer convection of a fluid withPrandtl number $\approx 1$. By measuring defect density and undulation wavenumber, we find that the onset of undulation chaos coincides with the theoretically predicted onset for stable, stationary undulations. At stronger driving, we observe a competition between ordered undulations and undulation chaos, suggesting bistability between a fixed-point attractor and spatiotemporal chaos. In the defect turbulent regime, we measured the defect creation, annihilation, entering, leaving, and rates. We show that entering and leaving rates through boundaries must be considered in order to describe the observed statistics. We derive a universal probability distribution function which agrees with the experimental findings.Comment: 4 pages, 5 figure

Semiquantum Chaos in the Double-Well

The new phenomenon of semiquantum chaos is analyzed in a classically regular double-well oscillator model. Here it arises from a doubling of the number of effectively classical degrees of freedom, which are nonlinearly coupled in a Gaussian variational approximation (TDHF) to full quantum mechanics. The resulting first-order nondissipative autonomous flow system shows energy dependent transitions between regular behavior and semiquantum chaos, which we monitor by Poincar\'e sections and a suitable frequency correlation function related to the density matrix. We discuss the general importance of this new form of deterministic chaos and point out the necessity to study open (dissipative) quantum systems, in order to observe it experimentally.Comment: LaTeX, 25 pages plus 7 postscript figures. Replaced figure 3 with a non-bitmapped versio

Chaos and Statistical Mechanics in the Hamiltonian Mean Field Model

We study the dynamical and statistical behavior of the Hamiltonian Mean Field (HMF) model in order to investigate the relation between microscopic chaos and phase transitions. HMF is a simple toy model of $N$ fully-coupled rotators which shows a second order phase transition. The canonical thermodynamical solution is briefly recalled and its predictions are tested numerically at finite $N$. The Vlasov stationary solution is shown to give the same consistency equation of the canonical solution and its predictions for rotator angle and momenta distribution functions agree very well with numerical simulations. A link is established between the behavior of the maximal Lyapunov exponent and that of thermodynamical fluctuations, expressed by kinetic energy fluctuations or specific heat. The extensivity of chaos in the $N \to \infty$ limit is tested through the scaling properties of Lyapunov spectra and of the Kolmogorov-Sinai entropy. Chaotic dynamics provides the mixing property in phase space necessary for obtaining equilibration; however, the relaxation time to equilibrium grows with $N$, at least near the critical point. Our results constitute an interesting bridge between Hamiltonian chaos in many degrees of freedom systems and equilibrium thermodynamics.Comment: 19 pages, 10 postscript figures included, Latex, Elsevier macros included. Invited talk at the conference ``Classical Chaos and its quantum manifestations'' in honour of Boris Chirikov, Sputnik conference of STATPHYS 20 - Toulouse, France - July 16-18, 1998. Revised version (added refs, changed part of the text and some figures) accepted for publication in Physica