(Weak)m-extremals andm-geodesics

Nonregular Abnormal Extremals

We study existence and rigidity (W1-isolatedness) of nonregular abnormal extremals of completely nonholonomic 2-distribution (nonregularity means that such extremals do not satisfy the strong generalized Legendre-Clebsch condition). Introducing the notion of diagonal form of the second variation, we generalize some results of A. Agrachev and A. Sarychev about rigidity of regular abnormal extrem...

Injectivity and adjoint extremals

The following investigation deals with injectivity results for general diffeomorphisms as well as for Haar’s transformation. We apply these results to adjoint variational problems introduced by Haar [6]. In particular, we prove a generalization of Krust’s theorem for two-dimensional adjoint extremals. AMS Classification Code: 26B10, 49B, 49L, 53A05, 53A10, 70G, 70H

Optimality of Broken Extremals

In this paper we analyse the optimality of broken Pontryagin extremal for an n -dimensional affine control system with a control parameter, taking values in a k dimensional closed ball. We prove the optimality of broken normal extremals when n = 3 and the controllable vector fields form a contact distribution, and when the Lie algebra of the controllable fields is locally orthogonal to the sing...

Familial antithrombin III deficiency andM pneumoniae pneumonia

deficiency' and reflects the importance of this serine protease inhibitor for the anticoagulant activity of heparin. Our experience shows the importance of screening for an underlying disorder in the young with thrombosis and strongly suggests that prophylactic measures aimed at preventing thrombosis should be considered in acutely ill subjects with infection and familial thrombophilia. 1 Rosen...

Singular extremals on Lie groups