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We show the local null-controllability of a fluid-structure interaction system coupling a viscous incompressible fluid with a damped beam located on a part of its boundary. The controls act on arbitrary small parts of the fluid domain and of the beam domain. In order to show the result, we first use a change of variables and a linearization to reduce the problem to the null-controllability of a Stokes-beam system in a cylindrical domain. We obtain this property by combining Carleman inequalities for the heat equation, for the damped beam equation and for the Laplace equation with high-frequency estimates. Then, the result on the nonlinear system is obtained by a fixed-point argument.

We consider the controllability of a viscous incompressible fluid modeled by the Navier–Stokes system with a nonlinear viscosity. To prove the controllability to trajectories, we linearize around a trajectory and the corresponding linear system includes a nonlocal spatial term. Our main result is a Carleman estimate for the adjoint of this linear system. This estimate yields in a standard way the null controllability of the linear system and the local controllability to trajectories. Our method to obtain the Carleman estimate is completely general and can be adapted to other parabolic systems when a Carleman estimate is available.

This paper examines the role that corporate social responsibility can play in advancing hospital management. Corporate social responsibility is the integration of social and environmental concerns within business operations. The authors discuss how corporate social responsibility can help hospitals and provide suggestions to hospitals in deciding which corporate social responsibility initiatives to pursue.

Adsorption of chicken lymphocytes to HEp-2 cells infected with vaccinia virus was found to occur by two processes. In one, the lymphocytes were attached to the microvilli of the HEp-2 cells, and the lymphocyte and host cell were separated at a distance of up to 0.6 micron. In the other, there was direct and close binding of the lymphocytes to the infected HEp-2 cell. The lymphocyte and HEp-2 cell were separated by an apparent gap approximately 10 to 20 nm in width.