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In this paper we study the dynamical behaviour of a simple cosmological model defined by a spatially flat Robertson-Walker geometry, conformally coupled with a massive scalar field. We determine a Lyapunov-like function for the non-linear evolution equations. From this function we prove that all the stationary solutions are unstable. We also show that all initial conditions, different from the stationary points, originate an expanding universe in the asymptotic regime, with a scale parameter $a(t)$ that goes to infinity and the scalar field $\phi (t)$ that goes to zero in an oscillatory way . We also find two asymptotic solutions, valid for sufficiently large values of time. These solutions correspond to a radiation dominated phase and to a matter dominated phase, respectively

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The upside-down simple harmonic oscillator system is studied in the contexts of quantum mechanics and classical statistical mechanics. It is shown that in order to study in a simple manner the creation and decay of a physical system by ways of Gamow vectors we must formulate the theory in a time-asymmetric fashion, namely using two different rigged Hilbert spaces to describe states evolving towards the past and the future. The spaces defined in the contexts of quantum and classical statistical mechanics are shown to be directly related by the Wigner function.

The list of diseases associated with autoantibodies against tissues, cells, or specific autoantigens is growing, and many organs in the body are known to be affected by autoimmune injury. Until recently, the most well-known pancreatic autoimmune disorder was type 1 diabetes mellitus, where there is selective destruction of beta cells in the islets of Langerhans. Although an autoimmune process affecting the exocrine pancreas was suspected over four decades ago, it is only in the past 10 years or so that autoimmune chronic pancreatitis has been recognized as a distinct entity. Here we review the clinical, serologic, radiologic, and histologic features of autoimmune pancreatitis.