Suppose that V (x) is an exponentially localized potential and L is a constant coefficient differential operator. A method for computing the spectrum of L+V (x−x1)+ ...+V (x−xN ) given that one knows the spectrum of L+V (x) is described. The method is functional theoretic in nature and does not rely heavily on any special structure of L or V apart from the exponential localization. The result i...

Stability of stationary Navier-Stokes flows in , n ≥ 3, is discussed in the function space L or H (Hardy space). It is shown that a stationary flow w is stable in H (resp. L) if sup |x| · |w(x)| + sup |x|2|∇w(x)| (resp. ‖w‖(n,1) + ‖∇w‖(n/2,1)) is small. Explicit decay rates of the form O(t−β/2), 0 < β ≤ 1, are deduced for perturbations under additional assumptions on w and on initial data. The ...

MRI, CT and PET are developed methods for use before surgical intervention. They can unfortunately not be used during surgery, which means that most procedures have to rely on X-ray imaging, where repeated “snapshots” provide an internal patient view. Every change of state from surgery requires a new X-ray image, and procedures that can’t be visually monitored require surgeons to “works in dark...

Snowmelt in alpine ecosystems brings ample water, and together with above-freezing temperatures, initiates plant growth. In this scenario, rapid activation of photosynthesis is essential for a successful life-history strategy. But, strong solar radiation late spring enhances the risk photodamage, particularly before fully functional. We compared photoprotective strategy five forbs: one geophyte...

The continuous technological advance and increasing availability of new dental self adhesive resin cement in the market, coupled to the demands of daily clinical practice, have made the determine mechanical properties. This study evaluated the shear bond strength of ceramics cemented by three different dental self-adhesive resin cements. Shear bond strength was measured with an Instron servo hy...

We consider the boundary value problem $$\displaylines{ - \Delta u + c(x) = \alpha m(x) u^+ \beta u^- +f(x,u), \quad x \in \Omega, \cr \frac{\partial u}{\partial \eta} \sigma (x) =\alpha \rho u^+- +g(x,u), \partial }$$ where \((\alpha, \beta) \mathbb{R}^2\), \(c, m L^\infty (\Omega)\), \(\sigma, (\partial\Omega)\), and nonlinearities f g are bounded continuous functions. study asymmetric (Fucik...

For a subgroup of PGL(2,q) we show how some irreducible polynomials over Fq arise from the field invariant rational functions. The proofs rely on combining two actions PGL(2,F), one projective line F and other function F(x). functions in F(x) are used to that regular patterns exist factorization certain into polynomials. We use results about group orbit polynomial, whose included.