Screening and Treatment of Tobacco Use Disorder in Mental Health Clinics in New York State: Current Status and Potential Next Steps.

The prevalence of smoking is higher among individuals with serious mental illnesses than the general population. Evidence-based practices exist for tobacco cessation, but little is known about mental health clinics' tobacco cessation treatment practices/protocols. Mental health clinics in New York State were surveyed about their tobacco use treatment protocols and outdoor-smoking policies. One-third of clinics were not providing individual counseling for tobacco use disorder, 39% were not prescribing nicotine replacement therapy, and nearly half reported not prescribing bupropion or varenicline. Even smaller proportions reported implementing other clinical practice guidelines, with only 25.2% providing staff training and 20.3% having a dedicated staff member for coordinating tobacco use disorder treatment. Regarding outdoor smoke-free policies, 38% of clinics reported not allowing any tobacco use anywhere on grounds. Despite some successes, many clinics do not provide evidence-based tobacco use treatments, meaning important opportunities exist for mental health clinics and oversight agencies to standardize practices.

On stability and instability criteria for magnetohydrodynamics.

It is shown that for most, but not all, three-dimensional magnetohydrodynamic (MHD) equilibria the second variation of the energy is indefinite. Thus the class of such equilibria whose stability might be determined by the so-called Arnold criterion is very restricted. The converse question, namely conditions under which MHD equilibria will be unstable is considered in this paper. The following sufficient condition for linear instability in the Eulerian representation is presented: The maximal real part of the spectrum of the MHD equations linearized about an equilibrium state is bounded from below by the growth rate of an operator defined by a system of local partial differential equations (PDE). This instability criterion is applied to the case of axisymmetric toroidal equilibria. Sufficient conditions for instability, stronger than those previously known, are obtained for rotating MHD. (c) 1995 American Institute of Physics.

Dynamo theory, vorticity generation, and exponential stretching.

A discussion is given of the analogy between the dynamo equation for the generation of a magnetic field by the motion of an electrically conducting fluid and the equation for the evolution of vorticity of a viscous fluid. In both cases exponential stretching is an important feature of the underlying instability problem. For the "fast" dynamo problem, the existence of exponential stretching (i.e., the positivity of the Lyapunov exponent) somewhere in the flow is a necessary condition when the flow is smooth. An example is presented of a flow with exponential stretching (an Anosov flow) that supports fast dynamo action. A parallel treatment is described for the linearized Navier-Stokes equations for the motion of a viscous fluid. In this problem the analogous necessary condition for "fast vorticity generation" is the existence of some instability in the corresponding Euler (i.e., inviscid) equation. Dynamo theory methods give a second related result, namely a universal geometric estimate from below on the growth rate of a small perturbation in an inviscid fluid. This bound gives an effective sufficient condition for local instability for Eulers equations. In particular, it is proved that a steady flow with a hyperbolic stagnation point is unstable. The growth rate of an infinitesimal perturbation in a metric with derivatives depends on this metric. This dependence is completely described.

Instability criteria for steady flows of a perfect fluid.

An instability criterion based on the positivity of a Lyapunov-type exponent is used to study the stability of the Euler equations governing the motion of an inviscid incompressible fluid. It is proved that any flow with exponential stretching of the fluid particles is unstable. In the case of an arbitrary axisymmetric steady integrable flow, a sufficient condition for instability is exhibited in terms of the curvature and the geodesic torsion of a stream line and the helicity of the flow.